ABSTRACT
ABSTRACT: Serial prophylactic exchange blood transfusion (SPEBT) is increasingly used in sickle cell disease (SCD) pregnancy, despite a lack of robust evidence. The Transfusion Antenatally in Pregnant Women with Sickle Cell Disease (TAPS2) study assessed the feasibility and acceptability of conducting a definitive randomized controlled trial of SPEBT (intervention) vs standard care (control) in this population. Women aged ≥18 years with SCD, between 6+0 and 18+6 weeks of singleton gestation, were randomized 1:1 every 6 -10 weeks throughout pregnancy in 7 hospitals in England. The main outcomes were recruitment rate (primary outcome), acceptability, and retention. Secondary outcomes were safety and maternal/infant outcomes. In total, 194 women were screened over 42 months (extended because of the pandemic), 88 were eligible, and 35 (39.8%) consented to participate; 18 participants were randomized to intervention, and 17 to control. Follow-up data were collected on all participants. Twelve patients in the intervention group received at least 1 SPEBT, of these, 11 received ≥3. The remaining patient was withdrawn from SPEBT because of transfusion reaction. Sixteen control participants required at least 1 transfusion. There were no statistically significant differences in maternal, infant, and postnatal outcomes. A trend toward a lower incidence of vaso-occlusive crisis, preterm delivery, and improved birthweight was observed in the intervention. The study achieved satisfactory recruitment and retention, confirming its acceptability to participants. TAPS2 demonstrates that it is feasible to perform a definitive international trial of SPEBT in SCD pregnancy. These trials were registered at www.ClinicalTrials.gov as #NCT03975894 and International Standard Randomized Controlled Trial Number (www.isrctn.com; #ISRCTN52684446).
Subject(s)
Anemia, Sickle Cell , Feasibility Studies , Pregnancy Complications, Hematologic , Humans , Female , Pregnancy , Anemia, Sickle Cell/therapy , Adult , Pregnancy Complications, Hematologic/therapy , Pregnancy Complications, Hematologic/prevention & control , Exchange Transfusion, Whole Blood/methods , Pregnancy OutcomeABSTRACT
BACKGROUND: There are significant knowledge gaps regarding the effectiveness of serial prophylactic exchange blood transfusion (SPEBT) for pregnant women with sickle cell disease (SCD). The protocol for the randomised feasibility trial assessing SPEBT versus usual care in women with SCD (TAPS2 trial) has previously been published. This publication outlines the statistical and qualitative analysis plan for the study. METHODS AND DESIGN: TAPS2 is a randomised two-arm phase 2 feasibility trial with a nested qualitative study and health economic evaluation. Up to 50 pregnant women with SCD and a singleton pregnancy will be recruited and individually randomised to either SPEBT approximately every 6-10 weeks until delivery (intervention arm) or to usual care (control arm). Information will be collected on a range of feasibility and clinical outcomes. RESULTS: Due to the impact of COVID-19 on study recruitment, the initial study period of 24 months was extended to 48 months. Other protocol updates designed to mitigate the impact of COVID-19-related disruption included allowing for remote consent and conducting all qualitative interviews by telephone. The primary outcome for the trial is the overall recruitment rate. The number of women screened, eligible, consented, randomised and withdrawn will be summarised as a CONSORT flow diagram. Differences in clinical outcomes will additionally be presented as an initial assessment of efficacy and to inform sample size calculations for a future definitive trial. Qualitative interviews with trial participants and clinicians will be analysed using reflexive thematic analysis; data from interviews with participants who declined to participate in the trial will be extracted and incorporated into summary tables to report key findings. The health economic analysis plan is not covered by this update. CONCLUSION: The publication of this analysis plan is designed to aid transparency and to reduce the potential for reporting bias. TRIAL REGISTRATION: NIH registry ( www. CLINICALTRIALS: gov ), registration number NCT03975894 (registered 05/06/19); ISRCTN ( www.isrctn.com ), registration number ISRCTN52684446 (retrospectively registered 02/08/19).
Subject(s)
Anemia, Sickle Cell , COVID-19 , Humans , Female , Pregnancy , Pregnant Women , Feasibility Studies , Treatment Outcome , Anemia, Sickle Cell/diagnosis , Anemia, Sickle Cell/therapy , Exchange Transfusion, Whole BloodABSTRACT
BACKGROUND: Pregnancies in women with sickle cell disease (SCD) are associated with a higher risk of sickle and pregnancy complications. Limited options exist for treating SCD during pregnancy. Serial prophylactic exchange blood transfusion (SPEBT) has been shown to be effective in treating SCD outside pregnancy, but evidence is lacking regarding its use during pregnancy. The aim of this study is to assess the feasibility and acceptability of conducting a future phase 3 randomised controlled trial (RCT) to establish the clinical and cost effectiveness of SPEBT in pregnant women with SCD. METHODS: The study is an individually randomised, two-arm, feasibility trial with embedded qualitative and health economic studies. Fifty women, 18 years of age and older, with SCD and a singleton pregnancy at ≤ 18 weeks' gestation will be recruited from six hospitals in England. Randomisation will be conducted using a secure online database and minimised by centre, SCD genotype and maternal age. Women allocated to the intervention arm will receive SPEBT commencing at ≤ 18 weeks' gestation, performed using automated erythrocytapheresis every 6-10 weeks until the end of pregnancy, aiming to maintain HbS% or combined HbS/HbC% below 30%. Women in the standard care arm will only receive transfusion when clinically indicated. The primary outcome will be the recruitment rate. Additional endpoints include reasons for refusal to participate, attrition rate, protocol adherence, and maternal and neonatal outcomes. Women will be monitored throughout pregnancy to assess maternal, sickle, and foetal complications. Detailed information about adverse events (including hospital admission) and birth outcomes will be extracted from medical records and via interview at 6 weeks postpartum. An embedded qualitative study will consist of interviews with (a) 15-25 trial participants to assess experiences and acceptability, (b) 5-15 women who decline to participate to identify barriers to recruitment and (c) 15-20 clinical staff to explore fidelity and acceptability. A health economic study will inform a future cost effectiveness and cost-utility analysis. DISCUSSION: This feasibility study aims to rigorously evaluate SPEBT as a treatment for SCD in pregnancy and its impact on maternal and infant outcomes. TRIAL REGISTRATION: NIH registry (www.clinicaltrials.gov), registration number NCT03975894 (registered 05/06/19); ISRCTN (www.isrctn.com), registration number ISRCTN52684446 (retrospectively registered 02/08/19).
Subject(s)
Anemia, Sickle Cell/therapy , Blood Transfusion/methods , Pregnancy Complications/therapy , Prenatal Care/methods , Adolescent , Adult , Blood Transfusion/economics , Cost-Benefit Analysis , England , Feasibility Studies , Female , Follow-Up Studies , Humans , Middle Aged , Multicenter Studies as Topic , Pregnancy , Randomized Controlled Trials as Topic , Young AdultABSTRACT
District nurses require a vast array of skills to enable effective care delivery for patients living with a diagnosis of dementia in the community setting. Complex care needs provide challenges for the provision and delivery of district nursing services, which must be overcome to provide patientcentred care. Demographic and financial constraints hamper service delivery and the availability of services; however, district nurses are required to use their problem solving skills and tacit knowledge to deal with these challenges. The Northern Ireland Single Assessment Tool (NISAT) uses a person-centred framework to provide a holistic approach to care. The case study reflects a holistic and person centred approach to care for a person with dementia by a district nursing student.
Subject(s)
Dementia/nursing , Nurse's Role , Nurses, Community Health , Holistic Nursing , Humans , Nursing AssessmentABSTRACT
A district nurse is an expert generalist practitioner who uses advanced clinical skills and knowledge to fulfil an ever-evolving role. The district nurse is accountable for the care planning, coordination and management of people with multi-faceted and intricate health care needs. In addition, an interprofessional approach to health and social care is required to enable the district nurse to co-ordinate care and enable patients to be cared for and remain within their homes. As the demand on primary and community services increases, care is further enriched by working in partnership with families, carers and voluntary service providers. The nurse patient relationship is the founding component for person-centred, holistic care. Through holistic assessment and shared decision making, co-produced care planning permits people to fundamentally take ownership of their health and enhances formal care provision. This case study reflects the role of the district nurse in Northern Ireland, through comprehensive assessment in clinical practice and highlights how a therapeutic relationship, being centred on the patient and shared decision-making impact positively on the care process.
Subject(s)
Nurse's Role , Nurses, Community Health , Clinical Competence , Decision Making , Delivery of Health Care , Humans , Northern Ireland , Nurse-Patient Relations , Patient Care Planning , State MedicineABSTRACT
Supercritical fluids, exhibiting a combination of liquid-like solvation power and gas-like diffusivity, are a relatively unexplored medium for processing and crystallization of oligomer and polymeric semiconductors whose optoelectronic properties critically depend on the microstructure. Here we report oligomer crystallization from the polymer organic semiconductor, poly[2,5-bis(3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene] (PBTTT) in supercritical hexane, yielding needle-like single crystals up to several microns in length. We characterize the crystals' photophysical properties by time- and polarization-resolved photoluminescence (TPRPL) spectroscopy. These techniques reveal two-dimensional interchromophore coupling facilitated by the high degree of π-stacking order within the crystal. Furthermore, the crystals obtained from supercritical fluid were found to be similar photophysically as the crystallites found in solution-cast thin films and distinct from solution-grown crystals that exhibited spectroscopic signatures indicative of different packing geometries.
ABSTRACT
BACKGROUND AND AIM: Estimation of small bowel length is of interest following the recent development of device-assisted enteroscopy. This new technology allows access to the deep small bowel, but rates of examination of the entire small bowel (total enteroscopy) differ between study populations. Variation in small bowel length could factor into this observed irregularity in total enteroscopy rates. Medical literature contains limited information regarding small bowel length in living patients and conflicting data regarding small bowel length and its relationship to height and weight. We carried out small bowel measurements on surgical patients to further define the total length of the small bowel and its relationship to height, weight and body mass index (BMI). METHODS: Measurement of ileojejunal length on 91 surgical patients undergoing laparotomy for routine indications. Demographic data were collected for each subject, including height, weight and BMI. RESULTS: Small bowel length was found to vary widely between individuals (average 998.52 cm, range 630-1510 cm). Linear regression analysis demonstrated a statistically significant relationship between small bowel length and height (regression coefficient = 0.0561, P-value = 0.0238). A linear relationship between small bowel length and weight or BMI was not observed. CONCLUSIONS: Length of the small bowel in humans is pertinent to advances in deep enteroscopy and existing surgical applications such as intestinal bypass and prevention of short gut syndrome. If average small bowel length varies with height, total enteroscopy may be easier to achieve in patients who are short in stature.
Subject(s)
Endoscopy, Gastrointestinal/methods , Intestine, Small/anatomy & histology , Body Mass Index , Female , Humans , Male , Organ Size , Prospective StudiesABSTRACT
More than ever, district nurses require highly developed communication and interpersonal skills to enable and nurture a therapeutic relationship. The 'shift left'-whereby patients are being assessed and cared for in the community at a much earlier stage of their illness or recovery-has significant implications. The complexity of patient care and the need for collaborative working and shared decision making necessitates a focus on fostering person-centred care and improving the patient experience in practice. District nurses are adept communicators with a specialist body of knowledge and skills. In Northern Ireland, the single assessment tool (NISAT) is used by health professionals and follows a person-centred framework. This case study reflects on the assessment process used by a district nursing student in clinical practice and demonstrates how a therapeutic relationship is developed, thereby supporting person centredness.
Subject(s)
Community Health Nursing , Northern IrelandABSTRACT
Epidermoid cysts are extremely common and can occur in any hair-containing area. We present the case of a 20-year-old man with an epidermoid cyst in the perianal region. Epidermal cysts have been described in this area previously after haemorrhoidectomy, but cysts of the size seen in this case are rare in the absence of previous anal trauma. The diagnosis was confirmed by excision biopsy.
Subject(s)
Anus Diseases/surgery , Epidermal Cyst/surgery , Humans , Male , Young AdultABSTRACT
We tested laboratory rabbits from 2 US vendors for antibodies against hepatitis E virus (HEV); Seroprevalences were 40% and 50%. Retrospective analysis of an ocular herpes simplex 1 experiment demonstrated that HEV seropositivity had no effect on experiment outcome. HEV probably is widespread in research rabbits, but effects on research remain unknown.
Subject(s)
Antibodies, Viral/immunology , Hepatitis E virus/immunology , Hepatitis E/immunology , Animals , Genotype , Hepatitis E/virology , Hepatitis E virus/genetics , Herpes Simplex/immunology , Herpes Simplex/virology , Herpesvirus 1, Human/immunology , RNA, Viral/genetics , Rabbits , Retrospective Studies , Seroepidemiologic StudiesABSTRACT
PURPOSE: To determine the retinal oxygen saturation trend with onset of diabetes and increasing severity of diabetic retinopathy by comparing diabetic groups with and without retinopathy to controls. METHODS: A fundus camera-based dual-wavelength snapshot oximeter imaged retinas of healthy subjects and patients with and without diabetic retinopathy. The images were analyzed to determine oxygen saturation in major retinal arteries and veins, which is inversely proportional to optical density ratio. RESULTS: Control retinal oxygen saturation (n = 14) in arteries was 92.3 ± 4.2% and in veins, 57.2 ± 6.0%. Retinal oxygen saturation for diabetic patients with no signs of diabetic retinopathy (NDR, n = 45) in arteries was 96.3 ± 8.6% (P = 0.662) and in veins, 58.7 ± 7.5% (P = 0.998). Retinal oxygen saturation for diabetics with mild to moderate nonproliferative diabetic retinopathy (NPDR, n = 23) in arteries was 97.7 ± 5.8% (P = 0.590) and in veins, 61.1 ± 7.6% (P = 0.658). Retinal oxygen saturation for diabetics with severe NPDR (n = 12) in arteries was 102 ± 10.2% (P = 0.023) and in veins, 66.8 ± 8.4% (P < 0.001). Retinal oxygen saturation for patients with proliferative diabetic retinopathy (PDR, n = 13) in arteries was 103.6 ± 8.7% (P = 0.003) and in veins, 66.6 ± 10.2% (P = 0.026). Retinal oxygen saturation for all diabetics with retinopathy combined (all DR, n = 48) in arteries was 100.4 ± 7.6% (P = 0.004) and in veins, 64.2 ± 8.4% (P = 0.007). CONCLUSIONS: A trend of increasing retinal oxygen saturation was found from controls to NDR group to increasing levels of diabetic retinopathy, though significance was only reached for the comparison of controls to severe-NPDR, PDR, and all-DR groups.
Subject(s)
Diabetic Retinopathy/metabolism , Oxygen/metabolism , Retinal Artery/metabolism , Retinal Vein/metabolism , Adult , Analysis of Variance , Case-Control Studies , Female , Humans , Male , Middle Aged , Oximetry , Young AdultABSTRACT
PURPOSE: Bacterial keratitis, without effective antimicrobial treatment, leads to poor patient prognosis. Even after bacterial clearance, the host inflammatory response can contribute to corneal damage. Though Streptococcus pneumoniae (pneumococcus) is a common cause of bacterial keratitis, the role of host innate immunity during pneumococcal keratitis is not well characterized. This study investigated the role of Toll-like receptors (TLRs) during pneumococcal keratitis. MATERIALS AND METHODS: C57BL/6, as well as TLR2(-/-) and TLR4(-/-) mice, were infected with S. pneumoniae, and infected corneas were examined for 21 days. Quantitative real-time reverse-transcriptase polymerase chain reaction was performed using primers for genes involved in the inflammatory response and TLR signaling. Bacterial survival and leukocyte invasion were examined over a 72-h period. RESULTS: The corneal expression of TLR2, TLR4, and other inflammatory genes was increased at 72 h post-infection (p.i.) compared to uninfected C57BL/6 scratch controls. TLR2(-/-) mice showed a significant increase in bacterial survival at 24 h p.i. likely due to decreased neutrophil infiltration; however, after Day 5 p.i. observed clinical scores of TLR2(-/-) and C57BL/6 mice were not significantly different. In contrast, permanent corneal damage was observed for TLR4(-/-) mice over 21 days. Initially, both TLR(-/-) mouse strains exhibited lower expression levels in many immune genes, but returned to similar or elevated levels compared to C57BL/6 mice by 72 h p.i. CONCLUSIONS: TLR2 and TLR4 are involved in the response to pneumococcal keratitis and TLR2 may aid in bacterial clearance by recruitment of neutrophils to the cornea, whereas TLR4 may be necessary to modulate the immune response to limit cellular damage.
Subject(s)
Keratitis/immunology , Pneumococcal Infections/immunology , Streptococcus pneumoniae/immunology , Toll-Like Receptor 2/immunology , Toll-Like Receptor 4/immunology , Animals , Cornea/immunology , Cornea/microbiology , Cytokines/immunology , Cytokines/metabolism , Disease Models, Animal , Eye Infections, Bacterial/immunology , Eye Infections, Bacterial/metabolism , Keratitis/microbiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Neutrophils/immunology , Signal Transduction/immunology , Toll-Like Receptor 2/genetics , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolismABSTRACT
BACKGROUND: Capsule and pneumolysin (PLY) are two major virulence factors of Streptococcus pneumoniae. S. pneumoniae is one of the leading causes of bacterial endophthalmitis. The aim of this study is to determine whether passive immunization with the 23-valent pneumococcal polysaccharide vaccine (Pneumovax® 23; PPSV23) or PLY protects against pneumococcal endophthalmitis. METHODS: New Zealand white rabbits were passively immunized with antiserum to PLY, PPSV23, a mixture of PPSV23/PLY, or PBS (mock). Vitreous was infected with a clinical strain of S. pneumoniae. In a separate group of experiments, vancomycin was injected 4 hours post-infection (PI) for each passively immunized group. Severity of infection, bacterial recovery, myeloperoxidase (MPO) activity and percent loss of retinal function were determined. RESULTS: Passive immunization with each antiserum significantly lowered clinical severity compared to mock immunization (PPSV23 = 9.19, PPSV23/PLY = 10.45, PLY = 8.71, Mock = 16.83; P = 0.0467). A significantly higher bacterial load was recovered from the vitreous of PLY passively immunized rabbits 24 hours PI (7.87 log10 CFU) compared to controls (7.10 log10 CFU; P = 0.0134). Retinas from immunized rabbits were more intact. Vitreous of PLY (2.88 MPO untis/mL) and PPSV23/PLY (2.17) passively immunized rabbits had less MPO activity compared to controls (5.64; P = 0.0480), and both passive immunizations (PLY = 31.34% loss of retinal function, PPSV23/PLY = 27.44%) helped to significantly preserve retinal function compared to controls (64.58%; P = 0.0323). When vancomycin was administered 4 hours PI, all eyes were sterile at 24 hours PI. A significantly lower clinical severity was observed for rabbits administered the combination immunization (5.29) or PPSV23 (5.29) with vancomycin treatment compared to controls (17.68; P = 0.0469). CONCLUSIONS: Passive immunization with antisera to these antigens is effective in reducing clinical severity of pneumococcal endophthalmitis in rabbits. Addition of vancomycin to immunization is effective at eliminating the bacteria.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Endophthalmitis/prevention & control , Immunization, Passive/methods , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/administration & dosage , Streptolysins/administration & dosage , Vancomycin/therapeutic use , Animals , Bacterial Proteins/administration & dosage , Colony Count, Microbial , Disease Models, Animal , Electroretinography , Endophthalmitis/physiopathology , Pneumococcal Infections/physiopathology , Rabbits , Streptococcus pneumoniae/drug effectsABSTRACT
The exact mechanisms of HSV-1 establishment, maintenance, latency, reactivation, and also the courses of recurrent ocular infections remain a mystery. Comprehensive understanding of the HSV-1 disease process could lead to prevention of HSV-1 acute infection, reactivation, and more effective treatments of recurrent ocular disease. Animal models have been used for over sixty years to investigate our concepts and hypotheses of HSV-1 diseases. In this paper we present descriptions and examples of rabbit and mouse eye models of HSV-1 latency, reactivation, and recurrent diseases. We summarize studies in animal models of spontaneous and induced HSV-1 reactivation and recurrent disease. Numerous stimuli that induce reactivation in mice and rabbits are described, as well as factors that inhibit viral reactivation from latency. The key features, advantages, and disadvantages of the mouse and rabbit models in relation to the study of ocular HSV-1 are discussed. This paper is pertinent but not intended to be all inclusive. We will give examples of key papers that have reported novel discoveries related to the review topics.
Subject(s)
Eye Infections, Viral/physiopathology , Eye Infections, Viral/virology , Herpes Simplex/physiopathology , Herpes Simplex/virology , Herpesvirus 1, Human/physiology , Virus Activation/physiology , Virus Latency/physiology , Animals , Disease Models, Animal , Humans , Rabbits , Recurrence , Species SpecificityABSTRACT
BACKGROUND: Rabbits latent with HSV-1 strain McKrae spontaneously shed infectious virus and viral DNA into their tears and develop recurrent herpetic-specific corneal lesions. The rabbit eye model has been used for many years to assess acute ocular infections and pathogenesis, antiviral efficacy, as well as latency, reactivation, and recurrent eye diseases. This study used real-time PCR to quantify HSV-1 DNA in the saliva and tears of rabbits latent with HSV-1 McKrae. METHODS: New Zealand white rabbits used were latent with HSV-1 strain McKrae and had no ocular or oral pathology. Scarified corneas were topically inoculated with HSV-1. Eye swabs and saliva were taken from post inoculation (PI) days 28 through 49 (22 consecutive days). Saliva samples were taken four times each day from each rabbit and the DNA extracted was pooled for each rabbit for each day; one swab was taken daily from each eye and DNA extracted. Real-time PCR was done on the purified DNA samples for quantification of HSV-1 DNA copy numbers. Data are presented as copy numbers for each individual sample, plus all the copy numbers designated as positive, for comparison between left eye (OS), right eye (OD), and saliva. RESULTS: The saliva and tears were taken from 9 rabbits and from 18 eyes and all tested positive at least once. Saliva was positive for HSV-1 DNA at 43.4% (86/198) and tears were positive at 28.0% (111/396). The saliva positives had 48 episodes and the tears had 75 episodes. The mean copy numbers ± the SEM for HSV-1 DNA in saliva were 3773 ± 2019 and 2294 ± 869 for tears (no statistical difference). CONCLUSION: Rabbits latent with strain McKrae shed HSV-1 DNA into their saliva and tears. HSV-1 DNA shedding into the saliva was similar to humans. This is the first evidence that documents HSV-1 DNA in the saliva of latent rabbits.
Subject(s)
DNA, Viral/isolation & purification , Herpes Simplex/virology , Herpesvirus 1, Human/isolation & purification , Saliva/virology , Virus Latency , Virus Shedding , Animals , Disease Models, Animal , Herpesvirus 1, Human/genetics , Rabbits , Real-Time Polymerase Chain Reaction , Tears/virology , Viral LoadABSTRACT
Transfusions are a cause of significant patient morbidity as well as expense. Anesthesia literature has examined controlled intraoperative hypotension as a means for reducing blood loss and transfusions. Our hypothesis is that inversely increased blood pressure post-operatively would then lead to increased blood loss and transfusions.We examined 105 consecutive patients who underwent TKA. We found a significant odds ratio of 1.123 for pre-operative hematocrit. For post-operative blood pressure, we calculated an insignificant odds ratio of 1.007, proving no relationship between post-operative blood pressure and transfusions.This is the first study to examine increased post-operative blood pressure's contribution to transfusion rates. Although we confirmed that low pre-operative hematocrit contributes to increased transfusions, we did not find a relationship between post-operative blood pressure and transfusions.
Subject(s)
Arthroplasty, Replacement, Knee/adverse effects , Blood Loss, Surgical , Hypertension/etiology , Postoperative Complications , Transfusion Reaction , Adult , Aged , Aged, 80 and over , Blood Pressure , Female , Humans , Male , Middle Aged , Prognosis , Retrospective StudiesABSTRACT
PURPOSE: The purpose of this study was to determine whether active immunization against pneumolysin (PLY), or polysaccharide capsule, protects against the corneal damage associated with Streptococcus pneumoniae keratitis. METHODS: New Zealand White rabbits were actively immunized with Freund's adjuvant mixed with pneumolysin toxoid (ψPLY), Pneumovax 23 (PPSV23; Merck, Whitehouse Station, NJ), or phosphate-buffered saline (PBS), before corneal infection with 105 colony-forming units (CFU) of S. pneumoniae. Serotype-specific rabbit polyclonal antisera or mock antisera were passively administered to rabbits before either intravenous infection with 10¹¹ CFU S. pneumoniae or corneal infection with 105 CFU of S. pneumoniae. RESULTS: After active immunization, clinical scores of corneas of the rabbits immunized with ψPLY and Freund's adjuvant were significantly lower than scores of the rabbits that were mock immunized with PBS and Freund's adjuvant or with PPSV23 and Freund's adjuvant at 48 hours after infection (P ≤ 0.0010), whereas rabbits immunized with PPSV23 and Freund's adjuvant failed to show differences in clinical scores compared with those in mock-immunized rabbits (P = 1.00) at 24 and 48 hours after infection. Antisera from rabbits actively immunized with PPSV23 and Freund's adjuvant were nonopsonizing. Bacterial loads recovered from infected corneas were higher for the ψPLY- and PPSV23-immunized rabbits after infection with WU2, when compared with the mock-immunized rabbits (P ≤ 0.007). Conversely, after infection with K1443, the ψPLY-immunized rabbits had lower bacterial loads than the control rabbits (P = 0.0008). Quantitation of IgG, IgA, and IgM in the sera of ψPLY-immunized rabbits showed high concentrations of PLY-specific IgG. Furthermore, anti-PLY IgG purified from ψPLY-immunized rabbits neutralized the cytolytic effects of PLY on human corneal epithelial cells. Passive administration of serotype-specific antisera capable of opsonizing and killing S. pneumoniae protected against pneumococcal bacteremia (P ≤ 0.05), but not against keratitis (P ≥ 0.476). CONCLUSIONS: Active immunization with pneumococcal capsular polysaccharide and Freund's adjuvant fails to produce opsonizing antibodies, and passive administration of serotype specific opsonizing antibodies offers no protection against pneumococcal keratitis in the rabbit, whereas active immunization with the conserved protein virulence factor PLY and Freund's adjuvant is able to reduce corneal inflammation associated with pneumococcal keratitis, but has variable effects on bacterial loads in the cornea.
Subject(s)
Corneal Ulcer/prevention & control , Eye Infections, Bacterial/prevention & control , Pneumococcal Infections/prevention & control , Pneumococcal Vaccines/administration & dosage , Streptolysins/administration & dosage , Vaccination , Animals , Antibodies, Bacterial/blood , Bacterial Proteins/administration & dosage , Colony Count, Microbial , Corneal Ulcer/microbiology , Eye Infections, Bacterial/microbiology , Immunization, Passive , Immunoglobulin A/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Opsonin Proteins/immunology , Pneumococcal Infections/microbiology , Rabbits , Streptococcus pneumoniae/physiologyABSTRACT
PURPOSE: To quantify the lamina cribrosa insertion into the peripapillary sclera and optic nerve pia in normal (N) and early experimental glaucoma (EEG) monkey eyes. METHODS: Perfusion-fixed optic nerve heads (ONHs) from 21 animals were digitally reconstructed three dimensionally and delineated. Anterior Laminar Insertion Position (ALIP), Posterior Laminar Insertion Position (PLIP), Laminar Insertion Length (LIL; distance between the anterior and posterior laminar insertions), and Scleral Thickness (at the Anterior Sub-arachnoid space) were calculated for each ONH. Animals were pooled into four groups based on the kill condition (N vs. EEG) and perfusion IOP (10, 30, or 45 mm Hg) of each eye: N10-N10 (n = 6), N30/45-N10 (n = 6), EEG10-N10 (n = 3), and EEG30/45-N10 (n = 6). Glaucomatous EEG versus N eye differences in each group and each animal were required not only to achieve statistical significance (P < 0.05) but also to exceed physiologic intereye differences within the bilaterally normal groups. RESULTS: ALIP was significantly posterior (outward) in the EEG compared with N10 eyes of the EEG30/45-N10 group and 5 of 9 individual EEG eyes (difference range, 12-49 µm). PLIP was significantly posterior in the EEG eyes of both EEG groups and in 6 of 9 individual EEG eyes (range, 25-83 µm). LIL ranged from 90 to 190 µm in normal eyes and was significantly increased within the EEG eyes of both EEG groups and in 7 of 9 individual EEG eyes (difference range, 30-47 µm). CONCLUSIONS: Posterior migration of the lamina cribrosa is a component of early cupping in monkey EEG.
Subject(s)
Disease Models, Animal , Glaucoma/diagnosis , Optic Disk/pathology , Optic Nerve Diseases/diagnosis , Sclera/pathology , Animals , Axons/pathology , Cell Movement , Female , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Intraocular Pressure , Macaca fascicularis , Macaca mulatta , Male , Tonometry, OcularABSTRACT
OBJECTIVE: To determine the effects of oxygen fluctuations on pigment epithelial-derived factor (PEDF) and vascular endothelial growth factor (VEGF)/PEDF ratios in a relevant rat model of retinopathy of prematurity (ROP). METHODS: The expression of retinal PEDF mRNA and of VEGF and PEDF protein were determined using real-time polymerase chain reaction or enzyme-linked immunosorbent assays at different postnatal day ages for rat pups raised in room air (RA) or in a rat model mimicking ROP. Statistical outcomes were determined with factorial analyses of variance. Mean VEGF and PEDF protein levels were determined at different ages for rats in the ROP model and for RA-raised rats, and the ratio of VEGF/PEDF protein versus age was plotted. At postnatal day (P) 14, inner retinal plexus vascularization had extended to the ora serrata in pups raised in RA. In the ROP model, avascular retina persisted at P14 and intravitreous neovascularization developed at P18. Therefore, VEGF and PEDF expression was determined in the ROP model and in RA-raised rat pups at P14 and P18. RESULTS: Older age was associated with increased PEDF mRNA (p<0.001), PEDF protein (p=0.005), and VEGF protein (p=0.005), and VEGF protein (p<0.0001). Exposure to fluctuations of oxygen in the 50/10 oxygen-induced retinopathy model compared to RA was associated with increased PEDF mRNA (p=0.0185), PEDF protein (p<0.0001), or VEGF protein (p<0.0001). The VEGF/PEDF ratio favored angiogenic inhibition (<1.0) before but not on P14, when avascular retina persisted in the ROP model but not in RA. The VEGF/PEDF ratio favored angiogenesis (>1.0) at P14 and P 18 when intravitreous neovascularization occurred in the ROP model. CONCLUSIONS: Increased expression levels of VEGF and PEDF are associated with older postnatal day age or with exposure to fluctuations in oxygen in the 50/10 oxygen-induced retinopathy model compared to RA. PEDF protein more closely associates with avascular retinal features and neovascularization than does VEGF protein or the VEGF/PEDF in the ROP model. Although PEDF has been proposed as a potential treatment in ROP, interventional studies using PEDF in an ROP model to potentially reduce intravitreous neovascularization are required to determine timing, efficacy, and dose of PEDF.
Subject(s)
Eye Proteins/biosynthesis , Neovascularization, Pathologic/metabolism , Nerve Growth Factors/biosynthesis , Oxygen/pharmacology , Retina , Retinal Vessels/growth & development , Retinopathy of Prematurity , Serpins/biosynthesis , Vascular Endothelial Growth Factor A/biosynthesis , Animals , Animals, Newborn , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Eye Proteins/genetics , Eye Proteins/pharmacology , Gene Expression , Humans , In Situ Hybridization , Infant, Newborn , Neovascularization, Pathologic/pathology , Nerve Growth Factors/genetics , Nerve Growth Factors/pharmacology , Polymerase Chain Reaction , RNA, Messenger/analysis , Rats , Retina/drug effects , Retina/metabolism , Retina/pathology , Retinal Vessels/drug effects , Retinopathy of Prematurity/drug therapy , Retinopathy of Prematurity/metabolism , Retinopathy of Prematurity/pathology , Serpins/genetics , Serpins/pharmacology , Vascular Endothelial Growth Factor A/geneticsABSTRACT
PURPOSE: To determine the efficacy of a new formulation of topical dexamethasone 0.1%/povidone-iodine 0.4% (FST-100) in reducing clinical symptoms and infectious viral titers in a rabbit model of adenoviral keratoconjunctivitis. METHODS: Rabbit corneas were inoculated bilaterally with 2×10(6) plaque-forming-units (PFU) of adenovirus type 5 (Ad5) after corneal scarification. Animals were randomized 1:1:1:1 (five rabbits per group) to FST-100, 0.5% cidofovir, tobramycin/dexamethasone (Tobradex; Alcon Laboratories, Fort Worth, TX) ophthalmic suspension, and balanced salt solution (BSS; Alcon Laboratories). Treatment began 12 hours after viral inoculation and continued for 7 consecutive days. The eyes were clinically scored daily for scleral inflammation (injection), ocular neovascularization, eyelid inflammation (redness), friability of vasculature, inflammatory discharge (pus), and epiphora (excessive tearing). Eye swabs were collected daily before treatment for the duration of the study. Virus was eluted from the swabs and PFU determined by titration on human A549 cells, according to standard procedures. RESULTS: The FST-100 treatment resulted in significantly lower clinical scores (P<0.05) than did the other treatments. The 0.5% cidofovir exhibited the most ocular toxicity compared with FST-100, tobramycin/dexamethasone, and balanced salt solution treatments. FST-100 and 0.5% cidofovir significantly (P<0.05) reduced viral titers compared with tobramycin/dexamethasone or balanced salt solution. CONCLUSIONS: FST-100 was the most efficacious in minimizing the clinical symptoms of adenovirus infection in rabbit eyes. FST-100 and 0.5% cidofovir were both equally effective in reducing viral titers and decreasing the duration of viral shedding. By providing symptomatic relief in addition to reducing infectious virus titers, FST-100 should be a valuable addition to treatment of epidemic adenoviral keratoconjunctivitis.