Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 46
Filter
1.
Arch Clin Neuropsychol ; 37(6): 1091-1102, 2022 Aug 23.
Article in English | MEDLINE | ID: mdl-35366309

ABSTRACT

In the current healthcare climate, reimbursement for services is increasingly linked to the ability to demonstrate beneficial patient outcomes. Neuropsychology faces some unique challenges in outcomes research, namely, that neuropsychologists often do not follow patients over time and the effect of neuropsychological services on patient outcomes may not be fully realized until under another provider's care. Yet there is an urgent need for empirical evidence linking neuropsychological practice to positive patient outcomes. To provide a framework for this research, we define a core set of patient-centered outcomes and neuropsychological processes that apply across practice settings and patient populations. Within each area, we review the available existing literature on neuropsychological outcomes, identifying substantial gaps in the literature for future research. This work will be critical for the field to demonstrate the benefit of neuropsychological services, to continue to advocate effectively for reimbursement, and to ensure high-quality patient care.


Subject(s)
Delivery of Health Care , Neuropsychology , Humans , Neuropsychological Tests , Outcome Assessment, Health Care , Patient-Centered Care
2.
Unfallchirurg ; 120(7): 573-584, 2017 Jul.
Article in German | MEDLINE | ID: mdl-28643099

ABSTRACT

BACKGROUND: The key elements in the therapy of surgical site infections (SSI) are surgical debridement and local and systemic antibiotic therapy; however, due to increasing antibiotic resistance, the development of additional therapeutic measures is of great interest for future trauma and orthopedic surgery. METHOD: Against the background of our own experimental and clinical experiences and on the basis of the current literature, possible future anti-infective strategies were elaborated. RESULTS/CONCLUSIONS: Bacteriophages were discovered and clinically implemented approximately one century ago and have been used in Western Europe for about one decade. They are currently used mainly in patients with burn injuries. It is likely that bacteriophages will become of great importance in view of the increasing antibiotic multi-drug resistance; however, they will probably not entirely replace antibiotic drugs. A combined use of bacteriophages and antibiotics is likely to be a more reasonable efficient therapy. In addition, the clinical importance of antimicrobial peptides (AMP) also increases. Up to now the possible use of AMPs is still experimental; however, individual AMPs are already established in the routine therapy (e. g. colistin). Further diagnostic and therapeutic measures may include photodynamic therapy, ultraviolet (UV) light application and differentiated genome analysis as well as the individual metabolism situation (metabolomics) of the pathogen cell and the patient tissue.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/therapeutic use , Bacterial Infections/therapy , Drug Resistance, Multiple, Bacterial , Surgical Wound Infection/therapy , Colistin/therapeutic use , Combined Modality Therapy , Debridement , Genome, Bacterial , Humans , Metabolomics , Photochemotherapy , Ultraviolet Therapy
3.
Mol Psychiatry ; 21(12): 1752-1767, 2016 12.
Article in English | MEDLINE | ID: mdl-26809838

ABSTRACT

Recombinant human erythropoietin (EPO) improves cognitive performance in neuropsychiatric diseases ranging from schizophrenia and multiple sclerosis to major depression and bipolar disease. This consistent EPO effect on cognition is independent of its role in hematopoiesis. The cellular mechanisms of action in brain, however, have remained unclear. Here we studied healthy young mice and observed that 3-week EPO administration was associated with an increased number of pyramidal neurons and oligodendrocytes in the hippocampus of ~20%. Under constant cognitive challenge, neuron numbers remained elevated until >6 months of age. Surprisingly, this increase occurred in absence of altered cell proliferation or apoptosis. After feeding a 15N-leucine diet, we used nanoscopic secondary ion mass spectrometry, and found that in EPO-treated mice, an equivalent number of neurons was defined by elevated 15N-leucine incorporation. In EPO-treated NG2-Cre-ERT2 mice, we confirmed enhanced differentiation of preexisting oligodendrocyte precursors in the absence of elevated DNA synthesis. A corresponding analysis of the neuronal lineage awaits the identification of suitable neuronal markers. In cultured neurospheres, EPO reduced Sox9 and stimulated miR124, associated with advanced neuronal differentiation. We are discussing a resulting working model in which EPO drives the differentiation of non-dividing precursors in both (NG2+) oligodendroglial and neuronal lineages. As endogenous EPO expression is induced by brain injury, such a mechanism of adult neurogenesis may be relevant for central nervous system regeneration.


Subject(s)
Erythropoietin/metabolism , Neurogenesis/drug effects , Oligodendroglia/drug effects , Animals , Brain/metabolism , Cell Differentiation/drug effects , Cell Differentiation/physiology , Central Nervous System/metabolism , Cognition/drug effects , Hippocampus/metabolism , Hippocampus/physiology , Male , Mice , Mice, Inbred C57BL , Neurogenesis/physiology , Neurons/metabolism , Oligodendroglia/metabolism , Pyramidal Cells/drug effects , Pyramidal Cells/metabolism , Recombinant Proteins/metabolism
4.
Biofabrication ; 7(2): 025002, 2015 Apr 08.
Article in English | MEDLINE | ID: mdl-25850524

ABSTRACT

Bioimprinting, which involves capturing cell morphological details into a polymer matrix, provides a new class of patterned surfaces which opens an opportunity to investigate how cells respond to their own signatures and may introduce possibilities for regulating their behaviour. In this study, phenotypic details of human nasal chondrocytes (HNCs) were replicated in soft polydimethylsiloxane (PDMS) mould resulting in inverse replicas of cells, which have been termed here as 'negative bioimprint'. For the first time, the information from this negative bioimprint was then transferred into another PDMS layer resulting in surfaces which resemble cell morphology and were called 'positive bioimprints'. Soft lithography was used to transfer these details from PDMS into different polymers like polystyrene, tissue culture polystyrene and clinically used block co-polymer poly (ethylene glycol) terephthalate-poly (butylene terephthalate) (PEGT-PBT). Results obtained from surface characterization confirmed that fine details of cells were successfully replicated from cells to different polymer matrices without any significant loss of information during the different steps of pattern transfer. HNCs seeded on different polymer surfaces with positive and negative bioimprints exhibited distinct behaviour. Cells cultured on positive bioimprints were more spread out and displayed high levels of proliferation compared to those on negative bioimprints, where cells were more compact with lower proliferation.


Subject(s)
Molecular Imprinting , Polyesters/chemistry , Polyethylene Glycols/chemistry , Adolescent , Cartilage/cytology , Cells, Cultured , Chondrocytes/cytology , Dimethylpolysiloxanes/chemistry , Humans , Microscopy, Atomic Force , Surface Properties
5.
Mol Psychiatry ; 19(10): 1143-9, 2014 Oct.
Article in English | MEDLINE | ID: mdl-23999527

ABSTRACT

In 2007, a multifaceted syndrome, associated with anti-NMDA receptor autoantibodies (NMDAR-AB) of immunoglobulin-G isotype, has been described, which variably consists of psychosis, epilepsy, cognitive decline and extrapyramidal symptoms. Prevalence and significance of NMDAR-AB in complex neuropsychiatric disease versus health, however, have remained unclear. We tested sera of 2817 subjects (1325 healthy, 1081 schizophrenic, 263 Parkinson and 148 affective-disorder subjects) for presence of NMDAR-AB, conducted a genome-wide genetic association study, comparing AB carriers versus non-carriers, and assessed their influenza AB status. For mechanistic insight and documentation of AB functionality, in vivo experiments involving mice with deficient blood-brain barrier (ApoE(-/-)) and in vitro endocytosis assays in primary cortical neurons were performed. In 10.5% of subjects, NMDAR-AB (NR1 subunit) of any immunoglobulin isotype were detected, with no difference in seroprevalence, titer or in vitro functionality between patients and healthy controls. Administration of extracted human serum to mice influenced basal and MK-801-induced activity in the open field only in ApoE(-/-) mice injected with NMDAR-AB-positive serum but not in respective controls. Seropositive schizophrenic patients with a history of neurotrauma or birth complications, indicating an at least temporarily compromised blood-brain barrier, had more neurological abnormalities than seronegative patients with comparable history. A common genetic variant (rs524991, P=6.15E-08) as well as past influenza A (P=0.024) or B (P=0.006) infection were identified as predisposing factors for NMDAR-AB seropositivity. The >10% overall seroprevalence of NMDAR-AB of both healthy individuals and patients is unexpectedly high. Clinical significance, however, apparently depends on association with past or present perturbations of blood-brain barrier function.


Subject(s)
Autoantibodies/blood , Blood-Brain Barrier/metabolism , Mood Disorders/metabolism , Parkinson Disease/metabolism , Receptors, N-Methyl-D-Aspartate/immunology , Schizophrenia/metabolism , Adult , Aged , Animals , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Cerebral Cortex/metabolism , Endocytosis/physiology , Female , Genome-Wide Association Study , Humans , Influenza, Human/genetics , Influenza, Human/metabolism , Male , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Mood Disorders/genetics , Neurons/metabolism , Parkinson Disease/genetics , Polymorphism, Single Nucleotide , Receptors, N-Methyl-D-Aspartate/genetics , Schizophrenia/genetics
6.
Mol Psychiatry ; 19(1): 108-14, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23164818

ABSTRACT

Epidemiological and genetic data support the notion that schizophrenia and bipolar disorder share genetic risk factors. In our previous genome-wide association study, meta-analysis and follow-up (totaling as many as 18 206 cases and 42 536 controls), we identified four loci showing genome-wide significant association with schizophrenia. Here we consider a mixed schizophrenia and bipolar disorder (psychosis) phenotype (addition of 7469 bipolar disorder cases, 1535 schizophrenia cases, 333 other psychosis cases, 808 unaffected family members and 46 160 controls). Combined analysis reveals a novel variant at 16p11.2 showing genome-wide significant association (rs4583255[T]; odds ratio=1.08; P=6.6 × 10(-11)). The new variant is located within a 593-kb region that substantially increases risk of psychosis when duplicated. In line with the association of the duplication with reduced body mass index (BMI), rs4583255[T] is also associated with lower BMI (P=0.0039 in the public GIANT consortium data set; P=0.00047 in 22 651 additional Icelanders).


Subject(s)
Bipolar Disorder/genetics , Chromosome Aberrations , Chromosomes, Human, Pair 16/genetics , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide/genetics , Schizophrenia/genetics , Adult , Aged , Aged, 80 and over , Bipolar Disorder/complications , Bipolar Disorder/epidemiology , Europe , Female , Gene Expression Profiling , Genome-Wide Association Study , Genotype , Humans , International Cooperation , Male , Middle Aged , Odds Ratio , Oligonucleotide Array Sequence Analysis , Risk Factors , Schizophrenia/complications , Schizophrenia/epidemiology , Young Adult
7.
Transl Psychiatry ; 3: e254, 2013 Apr 30.
Article in English | MEDLINE | ID: mdl-23632458

ABSTRACT

Claustrophobia, the well-known fear of being trapped in narrow/closed spaces, is often considered a conditioned response to traumatic experience. Surprisingly, we found that mutations affecting a single gene, encoding a stress-regulated neuronal protein, can cause claustrophobia. Gpm6a-deficient mice develop normally and lack obvious behavioral abnormalities. However, when mildly stressed by single-housing, these mice develop a striking claustrophobia-like phenotype, which is not inducible in wild-type controls, even by severe stress. The human GPM6A gene is located on chromosome 4q32-q34, a region linked to panic disorder. Sequence analysis of 115 claustrophobic and non-claustrophobic subjects identified nine variants in the noncoding region of the gene that are more frequent in affected individuals (P=0.028). One variant in the 3'untranslated region was linked to claustrophobia in two small pedigrees. This mutant mRNA is functional but cannot be silenced by neuronal miR124 derived itself from a stress-regulated transcript. We suggest that loosing dynamic regulation of neuronal GPM6A expression poses a genetic risk for claustrophobia.


Subject(s)
Membrane Glycoproteins/genetics , Nerve Tissue Proteins/genetics , Phobic Disorders/genetics , Adult , Amygdala/chemistry , Animals , Behavior, Animal , Electroretinography , Female , Genetic Engineering/methods , Heterozygote , Humans , Male , Mice , Mice, Inbred C57BL , Psychological Tests , Reflex, Startle/genetics , Reverse Transcriptase Polymerase Chain Reaction , Stress, Psychological/genetics
8.
Neth Heart J ; 21(3): 113-7, 2013 Mar.
Article in English | MEDLINE | ID: mdl-21604106

ABSTRACT

Ebstein's anomaly is a rare congenital heart malformation characterised by adherence of the septal and posterior leaflets of the tricuspid valve to the underlying myocardium. Associated abnormalities of left ventricular morphology and function including left ventricular noncompaction (LVNC) have been observed. An association between Ebstein's anomaly with LVNC and mutations in the sarcomeric protein gene MYH7, encoding ß-myosin heavy chain, has been shown by recent studies. This might represent a specific subtype of Ebstein's anomaly with a Mendelian inheritance pattern. In this review we discuss the association of MYH7 mutations with Ebstein's anomaly and LVNC and its implications for the clinical care for patients and their family members.

9.
Transl Psychiatry ; 1: e45, 2011 Oct 04.
Article in English | MEDLINE | ID: mdl-22833191

ABSTRACT

Genotype-phenotype correlations of common monogenic diseases revealed that the degree of deviation of mutant genes from wild-type structure and function often predicts disease onset and severity. In complex disorders such as schizophrenia, the overall genetic risk is still often >50% but genotype-phenotype relationships are unclear. Recent genome-wide association studies (GWAS) replicated a risk for several single-nucleotide polymorphisms (SNPs) regarding the endpoint diagnosis of schizophrenia. The biological relevance of these SNPs, however, for phenotypes or severity of schizophrenia has remained obscure. We hypothesized that the GWAS 'top-10' should as single markers, but even more so upon their accumulation, display associations with lead features of schizophrenia, namely positive and negative symptoms, cognitive deficits and neurological signs (including catatonia), and/or with age of onset of the disease prodrome as developmental readout and predictor of disease severity. For testing this hypothesis, we took an approach complementary to GWAS, and performed a phenotype-based genetic association study (PGAS). We utilized the to our knowledge worldwide largest phenotypical database of schizophrenic patients (n>1000), the GRAS (Göttingen Research Association for Schizophrenia) Data Collection. We found that the 'top-10' GWAS-identified risk SNPs neither as single markers nor when explored in the sense of a cumulative genetic risk, have any predictive value for disease onset or severity in the schizophrenic patients, as demonstrated across all core symptoms. We conclude that GWAS does not extract disease genes of general significance in schizophrenia, but may yield, on a hypothesis-free basis, candidate genes relevant for defining disease subgroups.


Subject(s)
Genetic Association Studies , Schizophrenia/diagnosis , Schizophrenia/genetics , Severity of Illness Index , Adult , Female , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Humans , Male , Polymorphism, Single Nucleotide/genetics , Risk
10.
Eur J Paediatr Dent ; 4(3): 133-7, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14529334

ABSTRACT

AIM: This was to determine the prevalence of Molar Incisor Hypomineralisation (MIH) and to evaluate possible causes of these enamel defects. METHODS: The study group consisted of 2,408 10-17 year old children born during 1985-1992 and living in Dresden (Germany). Enamel defects were recorded using the modified DDE index. Children with enamel defects and their parents were invited for a re-examination to record the medical history of the children during the first 3 years of life; these children were matched by age with other children with apparently normal first molars (control group). RESULTS: 135 (5.6%) of the children had demarcated opacities in at least one first molar, i.e. MIH. A significantly higher prevalence of MIH was seen in children born between 1989 and 1991 compared with those born before and after that period (p<0.01). The number of children returning for the medical history questionnaire was low, 31 out of 135 responded (test group). Although there were no significant differences between the test and control groups in terms of peri and neonatal complications or other health problems, the low return precluded any definitive interpretation. CONCLUSION: The overall prevalence of MIH in this study was low by comparison with other previous epidemiological reports.


Subject(s)
Dental Enamel Hypoplasia/epidemiology , Incisor/abnormalities , Molar/abnormalities , Adolescent , Child , Dental Enamel Hypoplasia/etiology , Germany/epidemiology , Humans , Prevalence , Tooth Calcification
11.
Hum Mol Genet ; 10(3): 283-90, 2001 Feb 01.
Article in English | MEDLINE | ID: mdl-11159947

ABSTRACT

The triple A syndrome (MIM 231550) is a rare autosomal recessive disorder characterized by adrenal insufficiency, achalasia and alacrima. The frequent association with a variety of neurological features may result in a severely disabling disease. We previously mapped the syndrome to a 6 cM interval on chromosome 12q13 and have now refined the critical region to 0 cM between KRT8 and D12S1651. Overlapping bacterial artificial chromosome (BAC) sequences of a high resolution BAC/P1-derived artificial chromosome (PAC) contig were screened for gene content and a novel gene encoding a 546 amino acid polypeptide was identified. In nine triple A syndrome patients eight different homozygous and compound heterozygous mutations were found in this gene, most of them leading to a truncated protein suggesting loss of function. RNA blotting experiments revealed marked expression in neuroendocrine and gastrointestinal structures, which are predominantly affected in triple A syndrome, supporting the hypothesis that mutations in this triple A syndrome gene (AAAS) are responsible for the disease. The predicted protein belongs to the family of WD repeat-containing proteins which exhibit a high degree of functional diversity including regulation of signal transduction, RNA processing and transcription.


Subject(s)
Abnormalities, Multiple/genetics , Adrenal Insufficiency , Esophageal Achalasia , Lacrimal Apparatus/abnormalities , Repetitive Sequences, Nucleic Acid/genetics , Abnormalities, Multiple/pathology , Amino Acid Sequence , Base Sequence , Chromosomes, Human, Pair 12/genetics , DNA/chemistry , DNA/genetics , DNA Mutational Analysis , Family Health , Female , Genetic Predisposition to Disease , Humans , Male , Microsatellite Repeats , Molecular Sequence Data , Mutation , Pedigree , Polymorphism, Single-Stranded Conformational , Syndrome
12.
Arch Psychiatr Nurs ; 13(2): 74-9, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10222635

ABSTRACT

Clinical learning experiences provide a means for developing the knowledge, skills, and values essential for practice in nursing. Although some research has examined student stress in the beginning of a clinical course, few studies have focused on the stress of clinical practice at the completion of a course. This research examined the stress and challenge of psychiatric clinical experiences in both associate and baccalaureate nursing programs. Students (N = 476) from 12 randomly selected programs completed the Clinical Stress Questionnaire; 81 students were completing psychiatric nursing courses. Students in psychiatric courses reported moderate degrees of stress and challenge in their clinical experiences and positive emotions associated with their clinical practicum. In comparison with other courses in the curriculum, however, psychiatric clinical courses were among the least challenging. Findings suggest the need for innovative clinical teaching strategies that challenge students and extend their thinking about care of psychiatric patients.


Subject(s)
Clinical Competence , Education, Nursing, Associate , Education, Nursing, Baccalaureate , Psychiatric Nursing/education , Stress, Psychological/psychology , Students, Nursing/psychology , Adult , Curriculum , Emotions , Humans , Midwestern United States , Needs Assessment , Stress, Psychological/etiology , Surveys and Questionnaires
15.
Exp Eye Res ; 44(4): 481-90, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3595759

ABSTRACT

The swelling pressure of 115 human corneas was determined using a modified electronic balance modified to simultaneously record the swelling force and the thickness of the stroma. The swelling force was found to follow a straight-line dependence on the stromal thickness when plotted in a double logarithmic scale, which means that the swelling pressure of each cornea could be expressed by a power fit of the form SP = aTb, where SP is swelling pressure, T stromal thickness, and a and b are constants of the cornea. In 45 control corneas swollen in 0.9% NaCl, pH 7.4, 0.01 M Hepes buffer, the mean value (+/- S.D.) of 'a' and 'b' were 7.09 mmHg mm-1 (+/- 2.96) and -3.48 (+/- 0.20), respectively. This corresponded to a mean swelling pressure of 84.0 mmHg at a standard stromal thickness of 0.5 mm. In paired experiments, the swelling pressure was found to be influenced insignificantly (P greater than 0.05) by a number of conditions, including lowering the pH to 4.0, increasing the temperature to 37 degrees C, and increasing the NaCl concentration to 9%. A significant correlation was found between the swelling pressure and the dry weight of the specimen (P less than 0.05), indicating a considerable biological variation of the swelling pressure. It is shown, that this variation may explain the normal variation in human corneal thickness in vivo.


Subject(s)
Cornea/physiology , Cornea/cytology , Cornea/drug effects , Hot Temperature , Humans , Hydrogen-Ion Concentration , Manometry/methods , Pressure , Sodium Chloride/pharmacology , Water
17.
Graefes Arch Clin Exp Ophthalmol ; 224(5): 428-34, 1986.
Article in English | MEDLINE | ID: mdl-3530885

ABSTRACT

The endothelium of 30 pairs of human cadaver corneas was stained by trypan blue and the intercellular spaces were visualized by induced dilation prior to corneal culture. Trypan blue staining and induced dilation of intercellular spaces by 0.9% and 0.45% NaCl were found to be atraumatic. Only a fraction of damaged cells were stained by trypan blue. Endothelial cell losses in culture did not correlate with the number of trypan-blue stained cells, the post-mortem time, or donor age.


Subject(s)
Cornea/drug effects , Cytological Techniques/adverse effects , Extracellular Space/physiology , Tissue Donors , Trypan Blue/adverse effects , Adult , Aged , Cell Survival , Cornea/cytology , Cornea/ultrastructure , Culture Techniques , Endothelium/cytology , Endothelium/drug effects , Endothelium/ultrastructure , Extracellular Space/ultrastructure , Humans , Middle Aged
18.
Cornea ; 4(2): 71-9, 1985.
Article in English | MEDLINE | ID: mdl-3907976

ABSTRACT

Corneal endothelial cells were visualized in intact bovine eyes by specular microscopy of unstained and stained cell borders. The corneas were excised, and flat corneal preparations were studied by reflected and transmitted light. In the excised corneas, the cell borders were visualized by osmotically induced dilation of intercellular spaces, alizarin red staining, and a combination of alizarin red and trypan blue staining. In whole eyes and in excised corneas, the estimates of endothelial cell densities varied by less than 3% from one method of visualization to the next. Estimates of endothelial cell densities obtained in intact eyes at 1 mm Hg were highly correlated to, but 13.6% lower than, estimates in excised corneas. Estimates of endothelial cell density obtained at intraocular pressures of 50 mm Hg were 7.7% lower than estimates obtained at 1 mm Hg.


Subject(s)
Cornea/cytology , Cytological Techniques , Intercellular Junctions/ultrastructure , Animals , Anthraquinones , Calibration , Cattle , Cell Count , Endothelium/cytology , Osmosis
19.
Arch Ophthalmol ; 101(12): 1920-6, 1983 Dec.
Article in English | MEDLINE | ID: mdl-6197050

ABSTRACT

Human corneas were studied by means of electron microscopy after culture at 31 degrees C for two to 20 days in a medium containing 8% dextran T 500. Dextran T 500, a strong osmotic agent, was included in the culture medium to prevent excessive swelling of the cornea. In order to exclude the possibility that the observed effects were the result of osmotic changes during fixation, in each experiment, fixatives with different osmolalities were used (430, 574, 727, and 812 mOsm). After 8, 16, and 20 days of culture, vacuoles appeared that were filled with dextran; the cytoplasm was completely filled with these vacuoles. The vacuolization was not limited to the endothelium, but was also observed in stromal keratocytes and to a limited extent in the epithelium. It was concluded that the monolayer of endothelium was still intact after 20 days of culture in medium containing 8% dextran T 500, and, secondly, that the dextran might have been taken up by endocytosis. Whether or not the uptake of dextran has a long-term toxic effect on the corneal cells remains to be elucidated.


Subject(s)
Cornea/ultrastructure , Dextrans/pharmacology , Microscopy, Electron , Adolescent , Adult , Aged , Culture Media , Female , Humans , Male , Middle Aged , Osmolar Concentration , Osmosis/drug effects
20.
Acta Ophthalmol (Copenh) ; 61(2): 245-53, 1983 Apr.
Article in English | MEDLINE | ID: mdl-6349234

ABSTRACT

The endothelium was studied by light- and electronmicroscopy in a cryopreserved cornea transplanted to a woman with herpetic keratitis and removed after 18 months because of wound dehiscence and epithelialization of the anterior chamber. The graft was perfectly transparent and of normal thickness. Light microscopy revealed the existence of a continuous layer of endothelial cells, showing pronounced pleomorphism when examined in flat preparation, with large multinuclear cells between smaller more normal looking mononuclear cells. The heterogeneous cell pattern resembled that observable in vitro after freezing and 24 h of culture. The cells therefore are not considered to be in a steady state. The ultrastructure of the majority of the cells was similar to that of non-cryopreserved endothelium. Cell cohesion took place by tight junctions, the intercellular spaces were of normal width. Ultrastructurally there was, however, a cellular heterogeneity, due to the occurrence of light cells with few organelles, but always with intact cell membranes. These cells probably represent slow death of endothelial cells, demonstrated by falling cell density during the 18 months between grafting and examination. We conclude from this study that cells surviving the freezing can maintain a clinically normal endothelial function for 18 months by forming a continuous quasistatic monolayer of tightly bound living cells.


Subject(s)
Cornea/ultrastructure , Organ Preservation , Tissue Preservation , Adult , Corneal Transplantation , Endothelium/ultrastructure , Female , Freezing , Humans , Keratitis, Dendritic/surgery , Microscopy, Electron, Scanning
SELECTION OF CITATIONS
SEARCH DETAIL
...