Hospital volunteers: An innovative pipeline to increase the geriatrics workforce.

Objectives: There is an urgent need to expand the geriatrics workforce. By providing volunteers meaningful experiences with older adults, we hoped to stimulate interest in geriatrics.Design: Electronic mixed methods survey of volunteers from April 2018-October 2019Setting: Academic medical centerParticipants: 32 volunteersMeasurements: We conducted a mixed methods survey of volunteers to understand their experiences in the program, in part using a Likert scale. Two coders independently compared themes to ensure consensus.Results: Thirty-six percent (n = 32) completed surveys; 69% (n = 22) were women; most (59%) were first in their family to work in healthcare, and 81% (n = 26) had prior healthcare experience. Volunteers found patients to be engaging, and recognized that older adults need attention. Almost half (47%, n = 15) expressed interest in working with older adults before starting the program, which increased to 63% (n = 20) after the program. Most volunteers (n = 30, 94%) answered 'definitely yes' or 'probably yes' for feeling appreciated by patients, and 88% (n = 28) felt appreciated by patients' families.Conclusion: A volunteer program pairing companions with older age inpatients increased interest and appreciation for older adults. While additional research should examine whether such experiences influence career choices, this intervention proposes an innovative pipeline to increase the geriatrics workforce.

Characterizing Intervention Opportunities among Home-Delivered Meals Program Participants: Results from the 2017 National Survey of Older Americans Act Participants and a New York City Survey.

BACKGROUND: The Home Delivered Meals Program (HDMP) serves a vulnerable population of adults aged 60 and older who may benefit from technological services to improve health and social connectedness. OBJECTIVE: The objectives of this study are (a) to better understand the needs of HDMP participants, and (b) to characterize the technology-readiness and the utility of delivering information via the computer. DESIGN: We analyzed data from the 2017 NSOAAP to assess the health and functional status and demographic characteristics of HDMP participants. We also conducted a telephone survey to assess technology use and educational interests among NYC HDMP participants. MEASUREMENTS: Functional measures of the national sample included comorbidities, recent hospitalizations, and ADL/IADL limitations. Participants from our local NYC sample completed a modified version of the validated Computer Proficiency Questionnaire. Technology readiness was assessed by levels of technology use, desired methods for receiving health information, and interest in learning more about virtual senior centers. RESULTS: About one-third (32.4%) of national survey HDMP participants (n=902) reported insufficient resources to buy food and 17.1% chose between food or medications. Within the NYC HDMP participant survey sample (n=33), over half reported having access to the internet (54.5%), 48.5% used a desktop or laptop, and 30.3% used a tablet, iPad, or smartphone. CONCLUSION: The HDMP provides an opportunity to reach vulnerable older adults and offer additional resources that can enhance social support and improve nutrition and health outcomes. Research is warranted to compare technological readiness of HDMP participants across urban and rural areas in the United States.

Finding an Optimal Corneal Xenograft Using Comparative Analysis of Corneal Matrix Proteins Across Species.

Numerous animal species have been proposed as sources of corneal tissue for obtaining decellularized xenografts. The selection of an appropriate animal model must take into consideration the differences in the composition and structure of corneal proteins between humans and other animal species in order to minimize immune response and improve outcome of the xenotransplant. Here, we compared the amino-acid sequences of 16 proteins present in the corneal stromal matrix of 14 different animal species using Basic Local Alignment Search Tool, and calculated a similarity score compared to the respective human sequence. Primary amino acid structures, isoelectric point and grand average of hydropathy (GRAVY) values of the 7 most abundant proteins (i.e. collagen α-1 (I), α-1 (VI), α-2 (I) and α-3 (VI), as well as decorin, lumican, and keratocan) were also extracted and compared to those of human. The pig had the highest similarity score (91.8%). All species showed a lower proline content compared to human. Isoelectric point of pig (7.1) was the closest to the human. Most species have higher GRAVY values compared to human except horse. Our results suggest that porcine cornea has a higher relative suitability for corneal transplantation into humans compared to other studied species.

Congregate Meals: Opportunities to Help Vulnerable Older Adults Achieve Diet and Physical Activity Recommendations.

BACKGROUND: Through diet and exercise interventions, community centers offer an opportunity to address health-related issues for some of the oldest, most vulnerable members of our society. OBJECTIVES: The purpose of this investigation is to draw upon nationwide data to better characterize the population served by the congregate meals program and to gather more detailed information on a local level to identify opportunities for service enhancement to improve the health and well-being of older adults. DESIGN: We examined community center data from two sources: 2015 National Survey of Older Americans Act and surveys from two New York City community centers. To assess nationwide service delivery, we analyzed participant demographics, functional status defined by activities of daily living, and perceptions of services received. MEASUREMENTS: Participants from the two New York City community centers completed a four-day food record. Functional measures included the short physical performance battery, self-reported physical function, grip strength, and the Montreal Cognitive Assessment. RESULTS: Nationwide (n=901), most participants rated the meal quality as good to excellent (91.7%), and would recommend the congregate meals program to a friend (96.0%). Local level data (n=22) were collected for an in-depth understanding of diet, physical activity patterns, body weight, and objective functional status measures. Diets of this small, local convenience sample were higher in fat, cholesterol, and sodium, and lower in calcium, magnesium, and fiber than recommended by current United States Dietary Guidelines. Average time engaged in moderate physical activity was 254 minutes per week (SD=227), exceeding the recommended 150 minutes per week, but just 41% (n=9) and 50% (n=11) of participants engaged in strength or balance exercises, respectively. CONCLUSION: Research is warranted to test whether improvements in the nutritional quality of food served and access/supports for engaging in strength training within community centers could help older adults achieve diet and physical activity recommendations.

Purification and characterization of secretory IgA from baboon colostrum.

In this report, we describe a method for purifying secretory immunoglobulin A (sIgA) from baboon (Papio anubis) colostrum. The colostrum was first clarified by centrifugation and then analyzed with various anti-human Ig-specific immunologic reagents. Cross-reactive IgA in the baboon colostrum was identified by ELISA. Western blot analysis also demonstrated cross-reactive epitopes associated with human IgA1, IgA2, secretory component (SC), and joining (J) chain. To purify the sIgA, colostrum was separated into 4 distinct fractions by gel filtration chromatography. Analysis of the individual fractions by ELISA indicated that the IgA elutes over one peak. The IgA fraction was compared with purified human sIgA on SDS-PAGE, and exhibited heavy (H) chains, light (L) chains, SC, and J chain. The baboon colostrum was also analyzed by ELISA for specific IgG H and L chain epitopes utilizing monoclonal antibodies (MAbs). No significant quantity of IgG was detected in the baboon colostrum or in the individual 4 fractions, while L chain reactivity was observed in the sIgA fraction. The sIgA fraction was pooled, concentrated, and was found to contain approximately 7 mg/ml sIgA. To determine if the baboon sIgA was dimeric like human sIgA, the purified sIgA was sized by molecular sieve chromatography. The molecular size of the sIgA preparation (350 kDa) was determined empirically by comparison to known molecular species used to calibrate the column. In addition, native SDS-PAGE indicated that baboon sIgA, like human sIgA, migrates between IgG and IgM, suggesting it has a dimeric form. The purified baboon sIgA preparation should prove useful in the future study of mucosal immune responses induced in non-human primate species and for the generation of sIgA-specific immunological reagents.

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)

Adenovirus keratitis: a role for interleukin-8.

PURPOSE: Adenovirus type 19 (Ad19) infection of the human cornea results in a chronic, multifocal, subepithelial keratitis. Existing evidence suggests that early subepithelial corneal infiltrates are composed of polymorphonuclear neutrophils. In this study, the capacity of Ad19-infected human corneal stromal fibroblasts (HCFs) to produce neutrophil chemotactants (chemokines) was tested. METHODS: HCFs grown from human donor corneas and passaged thrice were infected with a corneal isolate of Ad19 or mock-infected with virus-free media. Bioactivity of the cell supernatants was tested by a neutrophil chemotaxis assay. Supernatants were assayed by enzyme-linked immunosorbent assay for the neutrophil chemotactants interleukin-8 (IL-8) and GRO-alpha. Corneal facsimiles were generated with HCFs and collagen type I, infected with Ad19, and assayed by immunohistochemistry. RESULTS: Ad19 infection of HCFs increased neutrophil chemotaxis from a baseline of 0.4+/-0.7 cells/high-powered field (hpf; mock-infected) to 21.8+/-2.3 cells/hpf (Ad19-infected). Chemotaxis was reduced by the addition of neutralizing antibodies against IL-8 and GRO-alpha. Infection of HCFs induced quantities of IL-8 protein 300- and 1000-fold over mock-infected controls at 4 and 24 hours, respectively (33 versus 11,813 pg/mL at 4 hours, and 57 versus 76,376 pg/mL at 24 hours, P< or = 0.001 for both). In contrast, GRO-alpha protein levels were only sevenfold higher at 24 hours postinfection (118 pg/mL in mock-infected controls versus 880 pg/mL in Ad19-infected cell supernatants). Neither chemokine was induced by infection of an immortalized human corneal epithelial cell line. Immunohistochemistry of infected corneal facsimiles demonstrated IL-8 in the extracellular matrix within 3 days after infection. CONCLUSIONS: Production of chemokines in infected tissues facilitates an early innate immune response to infection, and in the infected corneal stroma represents an elementary defense mechanism. Interleukin-8 may play a role in the development of subepithelial infiltrates in adenovirus keratitis.

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.

PCR assessment of HSV-1 corneal infection in animals treated with rose bengal and lissamine green B.

PURPOSE: In vivo, the ophthalmic dye rose bengal displays profound antiviral effects against herpes simplex virus (HSV)-1, thus limiting its utility in diagnosis of epithelial keratitis when used before viral culture is performed. In contrast, lissamine green B does not possess significant antiviral activity in vivo. To determine whether polymerase chain reaction (PCR) could successfully detect HSV-1 DNA in ocular samples that have been exposed to ophthalmic dyes, animal models were used to observe the presence of infectious HSV-1 and viral DNA in eyes treated with rose bengal or lissamine green B. METHODS: Animals were bilaterally infected with HSV-1 strain H129, and at daily intervals up to 16 days post infection (dpi) rose bengal or lissamine green B was instilled in the left eyes. The right eyes were not treated with dyes. Swabs of the dye-treated and untreated eyes were assayed by PCR for viral infectivity by culture and the presence of DNA specific for a fragment of the HSV-1 DNA polymerase gene. RESULTS: A statistically equivalent number of samples from lissamine green B-treated and untreated eyes were positive by both viral culture and PCR. In contrast, rose bengal significantly decreased the infectious virus present in ocular secretions. A total of 44% and 78% of the rose bengal-treated and untreated eye samples, respectively, were positive by culture from 1 through 16 dpi. PCR was more sensitive than culture for detection of HSV-1 in rose bengal-treated eyes, in that 74% of rose bengal-treated samples were positive by PCR compared with 44% that were positive by culture during the 16-day period studied. It was also noted that both rose bengal and lissamine green B treatments slightly prolonged the period during which viral DNA was detectable in ocular secretions by PCR, possibly because the singlet oxygen produced by these photoreactive dyes compromised ocular cellular, humoral, and nonspecific immune factors allowing viral DNA to persist for slightly longer periods. CONCLUSIONS: PCR can successfully detect HSV-1 DNA in ocular samples that are culture negative and contain rose bengal or lissamine green B. Visualization of ocular epithelial defects with lissamine green B does not interfere with detection of infectious virus or HSV-1 DNA.

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.

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.

Photorefractive keratectomy for myopia in the setting of adenoviral subepithelial infiltrates.

PURPOSE: To report a patient with persistent subepithelial corneal opacities 18 months after adenoviral keratoconjunctivitis who underwent photorefractive keratectomy for the correction of myopia. METHODS: Case report, review of medical literature, and slit-lamp photography. RESULTS: The patient underwent photorefractive keratectomy in each eye, 1 week apart, with ablation of central corneal opacities and resultant best-corrected visual acuity of BE, 20/20. Symptomatic subepithelial stromal infiltrates recurred in the peripheral but not the central cornea of each eye 3 months after laser treatment. CONCLUSIONS: Photorefractive keratectomy was successful in the correction of myopia and prevented the recurrence of adenoviral subepithelial corneal infiltrates within the laser-treated central cornea.

Acanthamoeba infection after radial keratotomy.

PURPOSE: To describe a case of Acanthamoeba infection of the cornea after radial and astigmatic keratotomy. METHODS: A 29-year-old man developed ulcerative keratitis in the right eye 6 weeks after uncomplicated radial and astigmatic keratotomy. RESULTS: Three sets of corneal cultures for bacteria and fungi were negative. Culture on non-nutrient agar grew Acanthamoeba organisms. Clinical improvement occurred after topical antiamebic therapy was instituted. CONCLUSIONS: Incisional keratotomy may predispose the cornea to delayed-onset infectious keratitis. Acanthamoeba should be considered as a possible cause of infection and should be cultured for in refractory cases.

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.

Postoperative Rhizopus scleritis in a diabetic man.

A 50-year-old diabetic man developed necrotizing scleritis with adjacent keratitis 4 weeks after uncomplicated cataract extraction and intraocular lens implantation through a scleral tunnel incision. Cultures of the necrotic sclera grew Rizopus species. Severe destruction of the globe ensued despite topical, subconjunctival, and intravenous amphotericin B, in combination with hyperbaric oxygen therapy. Histopathological examination of the enucleated globe was consistent with Rhizopus infection. One year later, the patient was well without signs of recurrence.

Cat's tooth keratitis: human corneal infection with Capnocytophaga canimorsus.

PURPOSE: To describe a patient with keratitis caused by Capnocytophaga canimorsus after traumatic injury with a cat's tooth. METHODS: Case report and review of the literature. RESULTS: Sixteen months after onset of infection, the patient regained 20/30 vision in the affected eye. However, he required 7 months of antibiotic therapy to eliminate the infection. CONCLUSION: C. canimorsus keratitis may follow penetrating corneal injury and wound contamination with cat saliva and may be recalcitrant to topical antibiotic therapy.

Photorefractive keratectomy for myopia in the setting of Thygeson's superficial punctate keratitis.

PURPOSE: To describe a patient with Thygeson's superficial punctate keratitis who underwent photorefractive keratectomy for the correction of myopia. METHODS: A 49-year-old woman with unilateral Thygeson's keratitis was examined before and after photorefractive keratectomy. RESULTS: A myopic patient underwent photorefractive keratectomy in the left eye and gained 20/20 uncorrected visual acuity. Seventeen months after surgery, symptomatic Thygeson's keratitis lesions recurred in the peripheral but not the central cornea. CONCLUSION: Photorefractive keratectomy reliably corrected myopia in a patient with previous Thygeson's keratitis. The recurrence of lesions only in the peripheral untreated cornea suggests that the inflammatory signal in Thygeson's keratitis may reside in the superficial corneal stroma.

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.

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.

Anatomy of mammalian conjunctival lymphoepithelium.

Ocular surface immune mechanisms are subservient to the fine function of the eye. A clear cornea with a smooth, well-lubricated facade is prerequisite to lucid vision. Hence, corneal inflammation and post-inflammatory scarring are intolerable, and the cornea contains a minimum of lymphoid elements. Although conjunctival dysfunction and consequent tear film deficiency can malign the corneal surface, conjunctival inflammation is tolerated to a considerable degree. In contrast to the human cornea, human conjunctiva contains an abundance of lymphoid tissue. Certain aspects of human conjunctival immunology elicit little debate. Langerhans cells are abundant in conjunctival epithelium. Isolated CD8+ suppressor/cytotoxic T cells predominate in conjunctival epithelium, while T cells in the substantia propria distribute equally between CD4+ T helper cells and CD8+ cells. Yet the presence of plasma cells in human conjunctiva, the expression of secretory component by human conjunctival epithelium, and the function of human conjunctival lymphoid follicles are in dispute. Confusion may derive in part from the use of inappropriate animal models; rodent conjunctiva does not appear to be a worthy facsimile for human conjunctiva. Discrepancies between different human studies likely result from variance in subject age, biopsy site and extent, histologic or histochemical technique, and perhaps the degree of inflammation present at the time of biopsy. Careful immunohistochemical and in situ molecular assays on well-defined loci within the conjunctiva of comparable human subjects may resolve such questions in the future. Organized mucosa-associated lymphoid tissue is rigorously defined as mucosal lymphoid follicles with an ultrastructurally distinct overlying lymphoepithelium. Based on available evidence, the epithelium overlying mammalian conjunctival lymphoid follicles does not contain distinct M cells. Whether zonal differences in morphology reflect real differences in the capacity to sample tear film antigens for presentation to the mucosal immune system remains to be established.