The Biology and Underlying Mechanisms of Cross-Presentation of Exogenous Antigens on MHC-I Molecules.

To monitor the health of cells, the immune system tasks antigen-presenting cells with gathering antigens from other cells and bringing them to CD8 T cells in the form of peptides bound to MHC-I molecules. Most cells would be unable to perform this function because they use their MHC-I molecules to exclusively present peptides derived from the cell's own proteins. However, the immune system evolved mechanisms for dendritic cells and some other phagocytes to sample and present antigens from the extracellular milieu on MHC-I through a process called cross-presentation. How this important task is accomplished, its role in health and disease, and its potential for exploitation are the subject of this review.

De Garengeot's hernia patients entirely treated laparoscopically: a safe and feasible alternative-a systematic review.

PURPOSE: Less than 450 cases of femoral hernias containing the vermiform appendix have been published since De Garengeot's first description. A laparoscopic treatment option opened 15 years ago seems reliable and safe. A literature review of all the patients who have benefited from this new therapeutic alternative is presented. METHODS: A systematic review using the German Society of Surgery's recommendations was performed for De Garengeot's hernias totally treated laparoscopically. Keywords searched included "De Garengeot hernia" OR "femoral hernia appendix" OR "crural hernia appendix." RESULTS: Only 29 out of 225 De Garengeot hernia's manuscripts were identified describing patients entirely treated laparoscopically: 25 patients by a transabdominal preperitoneal hernia repair (TAPP) and 4 patients by a total extraperitoneal (TEP) procedure; 85.1% were females. The mean age was 71 years. Twenty-two patients had pre-operative imaging tests, sonography (2), computed tomography (14), or both (6). Nevertheless, only 56% had a preoperative diagnosis. Twenty-one cases required urgent treatment, while programmed surgery was possible in 7 instances. An appendix-sparing procedure could be done in 16% of the TAPPs. No postoperative complications occurred. The median hospital stay was 2.5 days. CONCLUSIONS: The best surgical approach for a De Garengeot's hernia is not defined, and many critical questions remain unanswered. A better understanding of the diagnosis and treatment of this peculiar hernia will supply guidelines for clinicians who may encounter it hereafter. A fully laparoscopic approach seems perfectly safe and feasible for this entity, and it could be considered the first-line alternative if enough expertise is available.

Acoustic Environmental Conditions (Do Not?) Affect the Static Posturography Diagnostic Accuracy: A Test-Retest Reliability Study.

Static posturography assessed with force platforms is a procedure used to obtain objective estimates related to postural adjustments. However, controlling multiple intrinsic and extrinsic factors influencing the diagnostic accuracy is essential to obtain reliable measurements and recommend its use with clinical or research purposes. We aimed to analyze how different environmental acoustic conditions affect the test−retest reliability and to analyze the most appropriate number of trials to calculate a valid mean average score. A diagnostic accuracy study was conducted enrolling 27 healthy volunteers. All procedures were taken considering consistent device settings, posture, feet position, recording time, and illumination of the room. Three trials were recorded in a silent environment (35−40 dB) and three trials were recorded in a noisy environment (85−90 dB). Results showed comparable reliability estimates for both acoustic conditions (ICC = 0.453−0.962 and 0.621−0.952), but silent conditions demonstrated better sensitivity to changes (MDC = 13.6−76%). Mean average calculations from 2 and 3 trials showed no statistically significant differences (p > 0.05). Cross-sectional studies can be conducted under noisy or silent conditions as no significantly different scores were obtained (p > 0.05) and ICC were comparable (except oscillation area). However, longitudinal studies should consider silent conditions as they demonstrated better sensitivity to real changes not derived from measurement errors.

Nosocomial COVID-19 Infection in a Long-Term Hospital in Spain: Retrospective Observational Study.

Background and Objectives. The aim of this study is to compare clinical and epidemiological characteristics and outcomes in patients with versus without nosocomial COVID-19 after exposure to SARS-CoV-2 and to analyze the risk factors for severe outcomes of COVID-19 in a long-term hospital in Spain. Materials and methods. This retrospective, single-center observational study included all inpatients in a long-term hospital during a COVID-19 outbreak from 21 January to 15 March 2021. Results. Of 108 admitted patients, 65 (60.2%) were diagnosed with nosocomial COVID-19 disease (n = 34 women (52.3%), median age 77 years). In the univariable analysis, risk factors associated with nosocomial COVID-19 were dementia (OR 4.98 95% CI 1.58-15.75), dyspnea (OR 5.34 95% CI 1.69-16.82), asthenia (OR 5.10, 95% CI 1.40-18.60) and NECesidades PALiativas (NECPAL) (OR 1.28 95% CI 1.10-1.48). In the multivariable analysis, risk factors independently associated with nosocomial COVID-19 infection were dyspnea (aOR 7.39; 95% CI 1.27-43.11) and NECPAL (aOR 1.25; 95% CI 1.03-1.52). Of the 65 patients diagnosed with nosocomial COVID-19, 29 (44.6%) died, compared to 7/43 (16.2%) non-infected patients (OR 4.14, 95% CI 1.61-10.67). Factors associated with mortality in nosocomial COVID-19 were confusion (aOR 3.83; 95% CI 1.03-14.27) and dyspnea (aOR 7.47; 95% CI 1.87-29.82). The NECPAL tool played an important predictive role in both nosocomial COVID-19 infection and mortality (aOR 1.19, 95% CI: 1.00-1.41). Conclusions. In a long-term hospital, nosocomial COVID-19 main clinical characteristics associated with infection were dyspnea and NECPAL. Mortality was higher in the group with nosocomial COVID-19; risk factors were confusion and dyspnea. The NECPAL tool may help to predict progression and death in COVID-19.

Sudden acquired retinal degeneration in dogs: breed distribution of 495 canines.

PURPOSE: The purpose of this study was to describe breed, age, gender, and weight distribution of dogs affected with sudden acquired retinal degeneration (SARD) and to investigate whether SARD is more common in small breed dogs. METHODS: Medical records of dogs diagnosed with SARD confirmed by an electroretinogram were reviewed. Breed, age, gender, and weight were recorded when available. The same data were obtained for dogs with SARD described in the veterinary literature. RESULTS: Three hundred and two dogs were included from the ophthalmology practices and 193 dogs from the veterinary literature. Sixty breeds were present in the study. Mixed-breed dogs were the most common at 108 dogs (21.8%), followed by the Dachshund (68, 13.7%), Chinese Pug (44, 8.9%), Miniature Schnauzer (39, 7.9%), Maltese (23, 4.6%), Cocker Spaniel (22, 4.4%), Bichon Frise (18, 3.6%), Beagle (16, 3.2%), Brittany (15, 3.0%), and Pomeranian (10, 2.0%). Fifty other breeds were represented by 1-9 dogs each. The median age was 9 years (range = 10 months-16 years). The weight was known for 197 dogs. About 60.9% of dogs were less than 25 pounds, 31.5% were between 25 and 50 pounds, and 7.6% were greater than 50 pounds. Gender was recorded in 393 dogs: 217 female dogs and 176 male dogs. CONCLUSIONS: As previously reported, SARD is most common in middle-aged to older dogs. Smaller dogs of less than 25 pounds appear overrepresented, while large/giant breed dogs of greater than 50 pounds are infrequently diagnosed. In this study, there was no statistical significance between female and male dogs.

Tissue plasminogen activator for axillary Impella 5.0 with heparin-induced thrombocytopenia as a treatment of choice for acute Impella thrombosis: a case report.

Background: Patients with cardiogenic shock requiring temporary support with percutaneous ventricular assist device, such as Impella (Abiomed, Inc.), can develop heparin-induced thrombocytopenia (HIT) which requires use of alternative purge solution anticoagulation. There are limited recommendations on use of anticoagulation other than standard Unfractionated Heparin in 5% dextrose solution. Case summary: This case describes 69-year-old female who presented with symptoms of decompensated systolic heart failure and was found to be in cardiogenic shock and despite use of inotropes and vasopressors maintained low systolic blood pressure and low mixed venous oxygen saturation which lead to use of axillary Impella 5.0 (Abiomed, Inc.) who developed HIT. Purge solution anticoagulation was switched to Argatroban, but due to increased motor pressures, tissue plasminogen activator (tPA) was successfully used to maintain proper motor pressures. Ultimately, patient was transferred to an outside facility for a transplant evaluation. Discussion: This case demonstrates successful and safe use of tPA as an alternative purge solution although more data needed to support this finding.

A One-Year Follow Up Study on Disability in Mental Health Nursing Practice.

Disability is common in patients with mental disorders, and therapeutic approaches should promote functional recovery to achieve the highest quality of life. This study reports changes in WHODAS 2.0 scores at 1 year of follow-up among patients receiving care from a single mental-health nurse in a community setting in Spain and compare these changes by diagnosis (SMI vs. CMI). Baseline and 1-year follow-up scores were compared. For all participants, we collected sociodemographic information, clinical diagnosis, and disability scores according to WHODAS 2.0. Participating patients received the usual, non-manualized nursing intervention. Our sample comprised 133 patients, 75 of whom were assessed after 1 year. All patients had improved WHODAS 2.0 scores (difference of 9.20 ± 2.42; p < .001) in all domains except those domains related to work ("Life activities") and relationships ("Getting along"). Furthermore, almost half of the patients studied were no longer undergoing treatment with the nurse at 1-year follow-up.

Comparison of disability between common mental disorders and severe mental disorders using WHODAS 2.0.

INTRODUCTION: Mental disorders are among the leading causes of disability worldwide. Despite the fact that severe mental disorders (SMD) are associated with high disability, the impact of common mental disorders (CMD) is not negligible. In this work, we compare the disability measured with the WHODAS 2.0 scale of both diagnostic groups at the Mental Health Nurse facility. MATERIAL AND METHODS: Sociodemographic data, clinical diagnosis and disability scores were collected, using the WHODAS 2.0 scale, of the patients attended by the Mental Health specialist nurse at the Infanta Elena de Valdemoro Hospital (Madrid) and disability was compared in patients with SMD and CMD, using the Student t test. RESULTS: Our study sample consisted of 133 patients. Patients with CMD showed greater disability compared to patients with SMD. It was observed that the disability associated with CMD is higher, compared to SMD, this difference being significant for the domain of work (p < 0.001) and participation in society (p = 0.041). CONCLUSIONS: In this study we showed that the level of disability associated with CMD was higher in certain areas compared to SMD, this difference was of special relevance for the «Work¼ and «Participation¼ domains. This may serve to adapt the interventions aimed at these people and improve their quality of life.

Spectral domain optical coherence tomography (SD-OCT) assessment of the healthy female canine retina and optic nerve.

OBJECTIVE: To provide normative data for canine whole retinal thickness (WRT), nerve fiber layer thickness (NFL), photoreceptor layer thickness (PR), and outer nuclear layer thickness (ONL) using spectral domain optical coherence tomography. ANIMAL STUDIED: Twelve healthy adult intact female beagles. PROCEDURE: Horizontal volume scans through the area dorso-temporal from the optic nerve (superior retina), and the area ventro-temporal from the optic nerve (inferior retina) were used to evaluate the thickness of retinal NFL, PR, ONL, and WRT. Peripapillary circular scans were used to evaluate NFL thickness. Statistical analyses were performed to compare the thickness of the individual layers between the superior and inferior retina (paired t-test). One-way analysis of variance (ANOVA) was used to compare the thickness of peripapillary NFL between the superior, inferior, temporal and nasal quadrants of the circle scan. RESULTS: The WRT, PR, and NFL thickness were greater in the superior than in the inferior retina (198.7 ± 9.6 µm vs. 164.4 ± 6.4 µm, P < 0.0001; 95.5 ± 6.5 µm vs. 78.8 ± 7.4 µm, P < 0.0001; and 26.4 ± 1.6 µm vs. 25.0 ± 1.9 µm, P = 0.0236, respectively). No statistical difference was found between the ONL thickness of the superior and inferior retina (50.1 ± 6.4 µm vs. 44.3 ± 3.6, P = 0.0578). Peripapillary NFL thickness showed a similar tendency as the linear scans, with the superior quadrant having the greatest thickness (91.26 ± 7.0 µm) and the inferior quadrant being the thinnest (76.42 ± 9.2 µm) (P < 0.001). CONCLUSIONS: Results of our in vivo studies showed significant differences between thickness values for the superior (tapetal) and inferior (nontapetal) retinal regions.

Appendix-Sparing Transabdominal Preperitoneal Laparoscopic Hernioplasty for a De Garengeot's Hernia: Video Demonstration.

Background and Objectives: Less than 300 cases of a De Garengeot's hernia have been published. This rare femoral hernia with the vermiform appendix included appears almost exclusively on the right side, mainly in females, and it generally debuts as an incarcerated femoral hernia. Although most of the times there is a concomitant appendicitis, clinical signs of peritonitis are absent. The wide use of radiologic exams has not favored its preoperative diagnosis, but been usually found incidentally during a surgical emergency. The best surgical approach to a De Garengeot's hernia is not totally defined and many critical questions still remain unanswered. Open surgery is considered the standard treatment procedure, but since the emergence of laparoscopy for incarcerated hernias, this is certainly an option. Methods: We report the successful laparoscopic management of an 83-year-old woman who had been operated on her right inguinal hernia, with a Rutkow-Robbins' technique, 4 months earlier. She had noticed the protrusion of a lump in her right inguinal region for 2 months. Radiological studies were not conclusive. With a miss diagnosis of a recurrent incarcerated inguinal hernia, a minimal invasive endoscopic approach was performed. A representative case of this fully laparoscopic TAPP procedure is presented. Results: The patient made an uninterrupted recovery. She left the hospital the day after in a stable condition and has enjoyed good health since. Conclusion: A fully laparoscopic TAPP approach seems perfectly safe and feasible to treat this entity, and could be considered the first line alternative when enough expertise is available.

Comparison of disability between common mental disorders and severe mental disorders using WHODAS 2.0. / Comparación de la discapacidad entre trastornos mentales graves y comunes usando la escala WHODAS 2.0.

INTRODUCTION: Mental disorders are among the leading causes of disability worldwide. Despite the fact that severe mental disorders (SMD) are associated with high disability, the impact of common mental disorders (CMD) is not negligible. In this work, we compare the disability measured with the WHODAS 2.0 scale of both diagnostic groups at the Mental Health Nurse facility. MATERIAL AND METHODS: Sociodemographic data, clinical diagnosis and disability scores were collected, using the WHODAS 2.0 scale, of the patients attended by the Mental Health specialist nurse at the Infanta Elena de Valdemoro Hospital (Madrid) and disability was compared in patients with SMD and CMD, using the Student t test. RESULTS: Our study sample consisted of 133 patients. Patients with CMD showed greater disability compared to patients with SMD. It was observed that the disability associated with CMD is higher, compared to SMD, this difference being significant for the domain of work (p<0.001) and participation in society (p=0.041). CONCLUSIONS: In this study we showed that the level of disability associated with CMD was higher in certain areas compared to SMD, this difference was of special relevance for the «Work¼ and «Participation¼ domains. This may serve to adapt the interventions aimed at these people and improve their quality of life.

Combining a CAR and a chimeric costimulatory receptor enhances T cell sensitivity to low antigen density and promotes persistence.

Despite the high remission rates achieved using T cells bearing a chimeric antigen receptor (CAR) against hematogical malignancies, there is still a considerable proportion of patients who eventually experience tumor relapse. Clinical studies have established that mechanisms of treatment failure include the down-regulation of target antigen expression and the limited persistence of effective CAR T cells. We hypothesized that dual targeting mediated by a CAR and a chimeric costimulatory receptor (CCR) could simultaneously enhance T cell cytotoxicity and improve durability. Concomitant high-affinity engagement of a CD38-binding CCR enhanced the cytotoxicity of BCMA-CAR and CD19-CAR T cells by increasing their functional binding avidity. In comparison to second-generation BCMA-CAR or CD19-CAR T cells, double-targeted CAR + CD38-CCR T cells exhibited increased sensitivity to recognize and lyse tumor variants of multiple myeloma and acute lymphoblastic leukemia with low antigen density in vitro. In addition, complimentary costimulation by 4-1BB and CD28 endodomains provided by the CAR and CCR combination conferred increased cytokine secretion and expansion and improved persistence in vivo. The cumulatively improved properties of CAR + CCR T cells enabled the in vivo eradication of antigen-low tumor clones, which were otherwise resistant to treatment with conventional CAR T cells. Therefore, multiplexing targeting and costimulation through the combination of a CAR and a CCR is a powerful strategy to improve the clinical outcomes of CAR T cells by enhancing cytotoxic efficacy and persistence, thus preventing relapses of tumor clones with low target antigen density.

Structural basis for T cell alloreactivity among three HLA-B14 and HLA-B27 antigens.

The existence of cytotoxic T cells (CTL) cross-reacting with the human major histocompatibility antigens HLA-B14 and HLA-B27 suggests that their alloreactivity could be due to presentation of shared peptides in similar binding modes by these molecules. We therefore determined the crystal structures of the subtypes HLA-B*1402, HLA-B*2705, and HLA-B*2709 in complex with a proven self-ligand, pCatA (peptide with the sequence IRAAPPPLF derived from cathepsin A (residues 2-10)), and of HLA-B*1402 in complex with a viral peptide, pLMP2 (RRRWRRLTV, derived from latent membrane protein 2 (residues 236-244) of Epstein-Barr virus). Despite the exchange of 18 residues within the binding grooves of HLA-B*1402 and HLA-B*2705 or HLA-B*2709, the pCatA peptide is presented in nearly identical conformations. However, pLMP2 is displayed by HLA-B*1402 in a conformation distinct from those previously found in the two HLA-B27 subtypes. In addition, the complexes of HLA-B*1402 with the two peptides reveal a nonstandard, tetragonal mode of the peptide N terminus anchoring in the binding groove because of the exchange of the common Tyr-171 by His-171 of the HLA-B*1402 heavy chain. This exchange appears also responsible for reduced stability of HLA-B14-peptide complexes in vivo and slow assembly in vitro. The studies with the pCatA peptide uncover that CTL cross-reactive between HLA-B14 and HLA-B27 might primarily recognize the common structural features of the bound peptide, thus neglecting amino acid replacements within the rim of the binding grooves. In contrast, structural alterations between the three complexes with the pLMP2 peptide indicate how heavy chain polymorphisms can influence peptide display and prevent CTL cross-reactivity between HLA-B14 and HLA-B27 antigens.

Contribution of CYP1B1 mutations and founder effect to primary congenital glaucoma in Mexico.

PURPOSE: The frequency of primary congenital glaucoma (PCG)-causing CYP1B1 mutations varies importantly among distinct populations, ranging from 20% in Indonesians and Japanese to about 100% among the Saudi Arabians and Slovakian Gypsies. Thus, the molecular characterization of large groups of PCG from different ethnic backgrounds is important to establish the actual CYP1B1 contribution in specific populations. In this work, the molecular analysis of the CYP1B1 gene in a group of Mexican PCG patients is reported. MATERIAL AND METHODS: Thirty unrelated Mexican patients fulfilling the clinical criteria for PCG were included. Two cases were familial and with proven consanguinity, originating from distinct regions of the country. Polymerase chain reaction amplification and direct automated sequencing of the CYP1B1 coding region was performed in each participating subject. RESULTS: An identical pathogenic CYP1B1 mutation was demonstrated in 2 unrelated PCG subjects. The mutation consisted of a homozygous G to A transition at nucleotide position 1505 in exon 3, which predicted a substitution of glutamic acid for lysine at residue 387 of the protein (E387K). In the remaining 28 PCG subjects, no deleterious mutations were identified. Both subjects with the E387K mutation shared a same haplotype for 5 CYP1B1 intragenic single nucleotide polymorphisms, indicating a common origin of the allele. CONCLUSIONS: Mexican patients with PCG are rarely (less than 10%) due to CYP1B1 mutations. Available data indicate that most of the non-Brazilian Latin American PCG patients investigated to date are not due to CYP1B1 defects. Populations with low incidence of CYP1B1 mutations are appropriate candidates for the identification of novel PCG-causing genes.

Stem cell factor supports migration in canine mesenchymal stem cells.

Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25-30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.

Expression, purification and preliminary X-ray crystallographic analysis of the human major histocompatibility antigen HLA-B*1402 in complex with a viral peptide and with a self-peptide.

The product of the human major histocompatibility (HLA) class I allele HLA-B*1402 only differs from that of allele HLA-B*1403 at amino-acid position 156 of the heavy chain (Leu in HLA-B*1402 and Arg in HLA-B*1403). However, both subtypes are known to be differentially associated with the inflammatory rheumatic disease ankylosing spondylitis (AS) in black populations in Cameroon and Togo. HLA-B*1402 is not associated with AS, in contrast to HLA-B*1403, which is associated with this disease in the Togolese population. The products of these alleles can present peptides with Arg at position 2, a feature shared by a small group of other HLA-B antigens, including HLA-B*2705, the prototypical AS-associated subtype. Complexes of HLA-B*1402 with a viral peptide (RRRWRRLTV, termed pLMP2) and a self-peptide (IRAAPPPLF, termed pCatA) were prepared and were crystallized using polyethylene glycol as precipitant. The complexes crystallized in space groups P2(1) (pLMP2) and P2(1)2(1)2(1) (pCatA) and diffracted synchrotron radiation to 2.55 and 1.86 A resolution, respectively. Unambiguous solutions for both data sets were obtained by molecular replacement using a peptide-complexed HLA-B*2705 molecule (PDB code 1jge) as a search model.

Plasmocitoma mamario y cáncer de mama: a propósito de un caso / Breast Plasmacytoma and breast cancer: a case report

El plasmocitoma mamario es una neoplasia de células plasmáticas extremadamente infrecuente, con menos de cincuenta casos descritos en el último siglo. Por este motivo, apenas se dispone de datos acerca del abordaje, tratamiento y seguimiento más convenientes. Presentamos el caso de una paciente de 70 años que debutó con un plasmocitoma mamario y que un año después fue diagnosticada de un carcinoma mamario lobulillar ipsilateral. La asociación entre plasmocitoma y cáncer de mama no está descrita en la literatura, por lo que es muy complicado establecer un vínculo entre ambas entidades. Sin embargo, el abordaje terapéutico del plasmocitoma podría comprometer el tratamiento ulterior de un cáncer de mama, por lo que el tratamiento idóneo en estos casos sea probablemente la cirugía.

Breast plasmocytoma is an extremely rare plasma cell neoplasm, with less than 50 cases reported in the last century. This is the reason why we barely have data about optimal management, treatment and follow-up. We hereby report the case of a 70 year old woman diagnosed with breast plasmocytoma that developed lobular breast cancer a year later. The link between plasmocytoma and breast cancer has not been previously established. However, breast plasmocytoma treatment could compromise latter breast cancer approach, so probably the most suitable strategy in these cases should be breast surgery.Conclusions: There are clinical characteristics associated with complications in women with surgical management abortion in our center, such as admission diagnosis, unplanned pregnancy, previous abortion and type of evacuation. There are limitations regarding the quantity and quality of information, however, our results allow us to know the profile of patients treated for abortion in our center.

[Prion diseases]. / Enfermedades por priones.

This article is a retrospective review about cases of diseases caused by prions cared for in our hospital over a 17 year period. The objective was to establish specific guidelines for treatment, norms and attitudes in order to achieve greater understanding, effectiveness and quality care for these patients as well as counsel all teams involved in their care, in light of the advances made in investigation over most recent years and the absence of publications in nursing journals about this topic.

Retinal ganglion cell damage in an experimental rodent model of blast-mediated traumatic brain injury.

PURPOSE: To evaluate retina and optic nerve damage following experimental blast injury. METHODS: Healthy adult mice were exposed to an overpressure blast wave using a custom-built blast chamber. The effects of blast exposure on retina and optic nerve function and structure were evaluated using the pattern electroretinogram (pERG), spectral domain optical coherence tomography (OCT), and the chromatic pupil light reflex. RESULTS: Assessment of the pupil response to light demonstrated decreased maximum pupil constriction diameter in blast-injured mice using red light or blue light stimuli 24 hours after injury compared with baseline in the eye exposed to direct blast injury. A decrease in the pupil light reflex was not observed chronically following blast exposure. We observed a biphasic pERG decrease with the acute injury recovering by 24 hours postblast and the chronic injury appearing at 4 months postblast injury. Furthermore, at 3 months following injury, a significant decrease in the retinal nerve fiber layer was observed using OCT compared with controls. Histologic analysis of the retina and optic nerve revealed punctate regions of reduced cellularity in the ganglion cell layer and damage to optic nerves. Additionally, a significant upregulation of proteins associated with oxidative stress was observed acutely following blast exposure compared with control mice. CONCLUSIONS: Our study demonstrates that decrements in retinal ganglion cell responses can be detected after blast injury using noninvasive functional and structural tests. These objective responses may serve as surrogate tests for higher CNS functions following traumatic brain injury that are difficult to quantify.

Detection and characterization of glaucoma-like canine retinal tissues using Raman spectroscopy.

Early detection of pathological changes and progression in glaucoma and other neuroretinal diseases remains a great challenge and is critical to reduce permanent structural and functional retina and optic nerve damage. Raman spectroscopy is a sensitive technique that provides rapid biochemical characterization of tissues in a nondestructive and noninvasive fashion. In this study, spectroscopic analysis was conducted on the retinal tissues of seven beagles with acute elevation of intraocular pressure (AEIOP), six beagles with compressive optic neuropathy (CON), and five healthy beagles. Spectroscopic markers were identified associated with the different neuropathic conditions. Furthermore, the Raman spectra were subjected to multivariate discriminate analysis to classify independent tissue samples into diseased/healthy categories. The multivariate discriminant model yielded an average optimal classification accuracy of 72.6% for AEIOP and 63.4% for CON with 20 principal components being used that accounted for 87% of the total variance in the data set. A strong correlation (R2>0.92) was observed between pattern electroretinography characteristics of AEIOP dogs and Raman separation distance that measures the separation of spectra of diseased tissues from normal tissues; however, the underlining mechanism of this correlation remains to be understood. Since AEIOP mimics the pathological symptoms of acute/early-stage glaucoma, it was demonstrated that Raman spectroscopic screening has the potential to become a powerful tool for the detection and characterization of early-stage disease.