Resultados a medio plazo de la uretroplastia distal con colocación de sonda y sin ella. Análisis retrospectivo sobre la necesidad de reintervención y los resultados estéticos / Medium-term outcome after stented and un-stented distal urethroplasty: A retrospective analysis on redo-urethroplasty need and cosmetic results

Introducción: La tasa de complicaciones a largo plazo tras la reparación del hipospadias distal puede ascender al 20%, y aún no disponemos de directrices sobre la colocación de la sonda en la uretroplastia distal. Hemos analizado de forma retrospectiva la tasa de reintervención de la uretroplastia a medio plazo y los resultados estéticos tras un estudio piloto de 2años sobre las uretroplastias distales con colocación de sonda o sin ella.Materiales y métodosUn cirujano pediátrico realizó 11 procedimientos con la técnica de Snodgrass con colocación de sonda (grupo A) y 17 sin colocación de sonda (grupo B) en nuestra institución (2011-2013). La mediana de edad de los pacientes en la cirugía fue de 2,1 años (rango 1-8,5).Los criterios de inclusión fueron: defecto distal primitivo, un único cirujano en ambos procedimientos y alta sin sonda.La mediana de seguimiento fue de 6,4 años (rango 1,5-8,1).Los resultados clínicos y estéticos postoperatorios fueron evaluados al menos una vez mediante la herramienta HOSE (Hypospadias Objective Scoring Evaluation).El objetivo de nuestro estudio fue comparar las complicaciones y las tasas de repetición de la uretroplastia a medio plazo antes de iniciar un estudio aleatorizado. Se hizo un análisis retrospectivo. Se utilizó la prueba exacta de Fisher (p <0,05) para el análisis estadístico.ResultadosDe los 28 del total, 5 complicaciones requirieron una segunda cirugía: 2/11 casos con sonda, 3/17 sin sonda. Los resultados estéticos fueron satisfactorios en ambos grupos. Los resultados no alcanzaron significación estadística (p=1.000). (AU)

Introduction: Long-term complication rates after distal hypospadias repair can be close to 20%. There are no available guidelines regarding the need of a catheter in distal urethroplasty. We report a retrospective analysis on medium-term redo-urethroplasty rate and cosmetic results after a two-year pilot study on stented/un-stented distal urethroplasties.Materials and methodsA total of 11 stented (Group A) and 17 un-stented (Group B) Snodgrass-procedures were performed by one pediatric surgeon at our Institution (2011-2013). The median age at surgery was 2.1 years (range 1-8.5).Inclusion criteria were primitive distal defect, same surgeon in both interventions, catheter-free discharge.The median follow-up was 6.4 years (range 1.5-8.1).All patients received at least one post-operative clinical-cosmetic examination (HOSE).The aim of our study was to compare medium-term complications and redo-urethroplasty rates before starting a randomized study. A retrospective analysis was performed. We used Fisher's exact-test (P<0.05) for statistical analysis.ResultsOf 28 complications, 5 required redo-surgery: 2/11 stented-cases, 3/17 un-stented. Cosmetic results were satisfactory in both groups. These results were not statistically significant (P=1.000). (AU)

Medium-term outcome after stented and un-stented distal urethroplasty: A retrospective analysis on redo-urethroplasty need and cosmetic results.

INTRODUCTION: Long-term complication rates after distal hypospadias repair can be close to 20%. There are no available guidelines regarding the need for a catheter in distal urethroplasty. We report a retrospective analysis on medium-term redo-urethroplasty rate and cosmetic results after a two-years pilot study on stented/un-stented distal urethroplasties. MATERIALS AND METHODS: A total of 11 stented (Group A) and 17 un-stented (Group B) Snodgrass-procedures were performed by the same pediatric surgeon at our Institution (2011-2013). The median age at surgery was 2.1 years (range 1-8.5). Inclusion criteria were primitive distal defect, same surgeon in both interventions, catheter-free discharge. The median follow-up was 6.4 years (range 1.5-8.1). All patients received at least one post-operative clinical-cosmetic examination (HOSE). The aim of our study was to compare medium-term complications and redo-urethroplasty rates before starting a randomized study. A retrospective analysis was performed. We used Fisher's exact-test (P < 0.05) for statistical analysis. RESULTS: Of 28 complications, 5 required redo-surgery: 2/11 stented-cases, 3/17 un-stented. Cosmetic results were satisfactory in both groups. These results were not statistically significant (P = 1.000). CONCLUSION: Long-term follow-up is mandatory to know redo-urethroplasty rate and cosmetic outcome after distal stented/un-stented repair. Further studies are needed to evaluate the role of catheter placement and the definitive outcome in distal urethroplasty.

Medium-term outcome after stented and un-stented distal urethroplasty: A retrospective analysis on redo-urethroplasty need and cosmetic results. / Resultados a medio plazo de la uretroplastia distal con colocación de sonda y sin ella. Análisis retrospectivo sobre la necesidad de reintervención y los resultados estéticos.

INTRODUCTION: Long-term complication rates after distal hypospadias repair can be close to 20%. There are no available guidelines regarding the need of a catheter in distal urethroplasty. We report a retrospective analysis on medium-term redo-urethroplasty rate and cosmetic results after a two-year pilot study on stented/un-stented distal urethroplasties. MATERIALS AND METHODS: A total of 11 stented (Group A) and 17 un-stented (Group B) Snodgrass-procedures were performed by one pediatric surgeon at our Institution (2011-2013). The median age at surgery was 2.1 years (range 1-8.5). Inclusion criteria were primitive distal defect, same surgeon in both interventions, catheter-free discharge. The median follow-up was 6.4 years (range 1.5-8.1). All patients received at least one post-operative clinical-cosmetic examination (HOSE). The aim of our study was to compare medium-term complications and redo-urethroplasty rates before starting a randomized study. A retrospective analysis was performed. We used Fisher's exact-test (P<0.05) for statistical analysis. RESULTS: Of 28 complications, 5 required redo-surgery: 2/11 stented-cases, 3/17 un-stented. Cosmetic results were satisfactory in both groups. These results were not statistically significant (P=1.000). CONCLUSION: Long-term follow-up is mandatory to know redo-urethroplasty rate and cosmetic outcome after distal stented/un-stented repair. Further studies are needed to evaluate the role of catheter placement and the definitive outcome in distal urethroplasty.

An Italian pilot study of a psycho-social intervention to support family caregivers' engagement in taking care of patients with complex care needs: the Engage-in-Caring project.

BACKGROUND: The raising of disability and chronic illness burden among European population is calling for a new paradigm of care, focused on primary health care interventions. Engage-In-Caring is a novel multicomponent intervention clearly dedicated to improve family caregiver engagement in the care of patients with complex care needs, by supporting them to develop a stronger consciousness of their role, needs and skills. METHOD: Engage-In-Caring intervention's efficacy and feasibility have been evaluated through a single arm pre-post observational pilot study settled in Rome. A qualitative phase, consisting of literature analysis of caregivers' unmet needs and a final revision from an experts' group, led to the structuration of the intervention, following the Caregiver Health Engagement Model (CHE-Model). Afterwards, a quantitative phase allowed understanding the feasibility of the intervention through Kruskal-Wallis test on a sample of 47 caregivers. RESULTS: Results showed a reduction of the physical burden (Chi Squared = 6,483; p = .01) perceived by the caregivers and increase of the health literacy (Chi Squared = 3,560; p = .059) after the intervention. CONCLUSIONS: Feasibility tests on caregivers of patients with complex care needs are promising: this pilot study suggests a first effectiveness evidence, particularly concerning aspects related to burden perception and improvements in health literacy. Randomised controlled trials on larger samples are needed.

Sox2 is not required for melanomagenesis, melanoma growth and melanoma metastasis in vivo.

Melanoma is a dangerous form of skin cancer derived from the malignant transformation of melanocytes. The transcription factor SOX2 is not expressed in melanocytes, however, it has been shown to be differentially expressed between benign nevi and malignant melanomas and to be essential for melanoma stem cell maintenance and expansion in vitro and in xenograft models. By using a mouse model in which BRafV600E mutation cooperates with Pten loss to induce the development of metastatic melanoma, we investigated if Sox2 is required during the process of melanomagenesis, melanoma growth and metastasis and in the acquisition of resistance to BRAF inhibitors (BRAFi) treatments. We found that deletion of Sox2 specifically in Pten null and BRafV600E-expressing melanocytes did not prevent tumor formation and did not modify the temporal kinetics of melanoma occurrence compared to Sox2 wt mice. In addition, tumor growth was similar between Sox2 wt and Sox2 deleted (del) melanomas. By querying publicly available databases, we did not find statistically significant differences in SOX2 expression levels between benign nevi and melanomas, and analysis on two melanoma patient cohorts confirmed that Sox2 levels did not significantly change between primary and metastatic melanomas. Melanoma cell lines derived from both Sox2 genotypes showed a similar sensitivity to vemurafenib treatment and the same ability to develop vemurafenib resistance in long-term cultures. Development of vemurafenib resistance was not dependent on SOX2 expression also in human melanoma cell lines in vitro. Our findings exclude an oncogenic function for Sox2 during melanoma development and do not support a role for this transcription factor in the acquisition of resistance to BRAFi treatments.

[Role in mini-invasive surgery in children]. / Il ruolo della chirurgia ad approccio mini-invasivo in età pediatrica.

AIM: This paper describes our experience with minimally invasive surgery and underlines its increasingly important role in the treatment of pediatric patients. METHODS: The study included all those patients undergoing a minimally invasive surgical procedure between January 2006 and March 2012. Patient demographics, type of operation (classified according to disease and anatomic site), complications, and length of hospital stay (LOS) were recorded. RESULTS: Out of 12,596 surgeries, 1803 (14.3%) minimally invasive procedures were performed: Soave-Georgeson endorectal colon pull-through for Hirschsprung's disease (N.=82); colectomy for chronic inflammatory bowel disease (N.=37); ileal J-pouch ano-rectal Knight-Griffen anastomosis in colectomized patients with chronic ulcerative colitis (N.=35); Nissen fundoplication for gastroesophageal reflux disease (N.=148); cholecystectomy (N.=68); appendectomy (N.=341); laparoscopic or thoracoscopic tumor resection or biopsy (N.=90); reconstruction of the renal pelvi and ureters (N.=11); and Nuss thoracoplasty for pectus excavatum (N.=237). The median age was 3 years; the median LOS was 3 days; the complications rate was 0.9% (N.=18). CONCLUSION: According to our experience, minimally invasive surgery is a safe and efficacious alternative to conventional surgery (in terms of complications) also in children. It was associated with shorter LOS and improved quality of life, with less pain and better aesthetic results. It has become the preferred surgical treatment option by parents.

Abdominal wall defects: a 33-year unicentric experience.

AIM: The aim of this paper was to provide the main clinical features, surgical details, and long term outcome of patients with gastroschisis and omphalocele operated on at Giannina Gaslini Institute between 1976 and 2009. METHODS: All patients who were operated on between 1976 and 2009 for omphalocele or gastroschisis were included. Detailed informations regarding demographics, maternal history, type of delivery, associated anomalies, surgical details, complications, morbidity and mortality were collected. RESULTS: Sixty-one patients were included. Type of delivery did not interfere with outcome. Although patients with omphalocele had higher incidence of associated anomalies with their obvious impact on survival and quality of life, they showed a quicker recovery from surgery. Mortality rate was around 5%. Long-term outcome was available in 18 of them and proved to be satisfactory in all although almost 70% of them complained some gastrointestinal issues. CONCLUSION: Gastroschisis and Omphalocele showed improving survival and outcome during the last decades. Caesarean section proved not to confer advantages over vaginal delivery. Associated anomalies have the highest impact on survival being cardiac malformation the most significant risk factors. Although overall outcome is good in the majority of the patients, gastrointestinal and cosmetic issues seem to have a significant impact on quality of life and overall patients' perspectives.

Shifting from open surgical cut down to ultrasound-guided percutaneous central venous catheterization in children: learning curve and related complications.

PURPOSE: Tunneled indwelling central venous catheters (CVC) are essential in the management of children with cancer, hematological, nephrological disorders and for parenteral nutrition. The aim of this study is to present the experience of a single center of the transition from traditional open surgical cut down procedure (OSC) to ultrasound (US)-guided percutaneous CVC insertion, focusing on learning curve and related complications. METHODS: All CVCs inserted between April 2008 and November 2009 in children at the Gaslini Children Hospital were revised, and data on methods of cannulation, intraoperative and device-related complications and re-intervention were recorded. RESULTS: 194 CVCs were positioned in 188 patients. 128 out of 194 CVCs were positioned through an OSC technique, whereas the remaining 66 CVCs were inserted percutaneously with US guidance. Of the 27 recorded complications, 15 were mechanical events, 7 cases developed infection, whereas the remaining 5 (2.6%) were classified as intraoperative complications. A second surgical procedure was described in 23 (11.8%) cases. CONCLUSION: Shifting from OSC to US-guided percutaneous CVC insertion inevitably involves a challenging learning curve which is generally associated with high complication rates. Complications progressively decrease once a good experience in US guidance and percutaneous technique has been obtained.

Expression and localization of P2 nucleotide receptor subtypes during development of the lateral ventricular choroid plexus of the rat.

The choroid plexuses secrete cerebrospinal fluid (CSF) and regulate the brain's internal environment via the blood-CSF barrier. The permeability properties of the blood-CSF interface have been studied previously in adult and immature brains, however, little is known about the development of CSF secretion and its modulation. ATP influences secretion in other epithelia via ionotropic P2X or metabotropic P2Y receptors. P2 receptors have frequently been found to be down-regulated in the postnatal period, suggesting a developmental role for purinergic and pyrimidine signalling. The present study investigated the expression of P2 receptors in lateral ventricular choroid plexus in relation to recent studies of aquaporin-1 expression and rapid expansion of the lateral ventricles in rat embryos. In the present study mRNAs for all known mammalian nucleotide receptor subtypes, except P2X(7), were identified from as early as E15. P2X(7) mRNA was detected from E18. Indications of differential expression patterns were observed for the different subtypes during development: an apparent increase in expression for P2Y(2) and P2X(7), a decline in P2X(1-2,4), no detectable difference in expression levels for P2X(6) and P2Y(12-13) and transient expression peaks for P2X(3,5) and P2Y(1,4,6,14). P2X(4,5,7) and P2Y(1,4) receptor proteins were detected immunohistochemically in the choroidal epithelium from early in development (E15 or E18). Their differing developmental profiles suggest specific roles in the development of CSF secretion that may have particular relevance for the rapid expansion of the ventricles that occurs in the embryo. P2X(5) and P2Y(6) were also detected in the developing neuropendyma from P0 and P9, respectively.

Nitric oxide synthase II gene disruption: implications for tumor growth and vascular endothelial growth factor production.

The expression of a primary initiator of tumor angiogenic responses, vascular endothelial growth factor (VEGF), may be induced by nitric oxide (NO) in carcinoma cells. However, the net impact of NO on carcinogenesis remains unclear, because manipulation of NO levels has been shown to either stimulate or inhibit tumor growth. We have investigated the relationship between inducible NO synthase (NOS II), VEGF expression, and growth of B16-F1 melanoma over 14 days in wild-type (NOS II+/+) mice and in those in which the gene for NOS II has been deleted (NOS II-/-). B16-F1 tumor growth was measured as wet weight of the excised tissue. Tumor NOS II and VEGF localization were evaluated by immunohistochemistry, and VEGF mRNA levels were measured by Northern blot analysis. In NOS II+/+ mice inoculated with B16-F1 melanoma cells, macroscopic tumors were always observed at 14 days; however, 22% of NOS II-/- mice had no detectable tumor mass. Immunoreactive NOS II was detected in tumor cells of tumors grown in NOS II+/+ but not in NOS II-/- mice. Although immunoreactive VEGF was detected in the granules of tumor-associated mast cells from both NOS II+/+ and NOS II-/- mice, VEGF mRNA expression in tumors from NOS II-/- was half that in NOS II+/+ mice. Neither NOS II inhibition, exogenous NO, nor peroxynitrite influenced DNA synthesis in culture B16-F1 melanoma cells. The NO donor did not alter either VEGF mRNA levels or degranulation in cultures of the mast cell line RBL-2H3, but peroxynitrite increased both VEGF mRNA expression and degranulation. We conclude that host expression of NOS II contributes to induction of NOS II in the tumor and to melanoma growth in vivo, possibly by regulating the amount and availability of VEGF.

The importance of ERK activity in the regulation of cyclin D1 levels and DNA synthesis in human cultured airway smooth muscle.

The relationship between persistent ERK (extracellular signal-regulated kinase) activity, cyclin D1 protein and mRNA levels and cell cycle progression in human cultured airway smooth muscle was examined in response to stimulation by ET-1 (endothelin-1), thrombin and bFGF (basic fibroblast growth factor). Thrombin (0.3 and 3 u ml(-1)) and bFGF (0.3 and 3 nM) increased ERK activity for more than 2 h and increased cell number, whereas ET-1 (100 nM) transiently stimulated ERK activity and was non-mitogenic. The MEK1 (mitogen-activated ERK kinase) inhibitor, PD 98059 (30 microM), inhibited both ERK phosphorylation and activity, and either prevented (thrombin 0.3 and 3 u ml(-1), bFGF 300 pM) or attenuated (bFGF 3 nM) DNA synthesis. Thrombin and bFGF increased both cyclin D1 mRNA and protein levels. PD 98059 decreased cyclin D1 protein levels stimulated by the lower but not higher thrombin concentrations. Moreover, increases in cyclin D1 mRNA levels were unaffected by PD 98059 pretreatment, irrespective of the mitogen or its concentration, suggesting that inhibition of cyclin D1 protein levels occurred by a post-transcriptional mechanism. These findings indicate that the control of cyclin D1 protein levels may occur independently of the MEK1/ERK signalling pathways. The inhibition of S phase entry by PD 98059 at higher thrombin concentrations appears to result from effects on pathways downstream or parallel to those regulating cyclin D1 protein levels. These findings suggest heterogeneity in the signalling of DNA synthesis in human cultured airway smooth muscle.

Beta2-adrenergic receptor agonists and cAMP arrest human cultured airway smooth muscle cells in the G(1) phase of the cell cycle: role of proteasome degradation of cyclin D1.

Hyperplasia of airway smooth muscle (ASM) contributes to the airway hyperresponsiveness that characterizes asthma. We have investigated the relationship between cAMP-induced growth arrest of ASM cells and thrombin-stimulated, extracellular-regulated protein kinase (ERK) activity, cyclin D1, and the restriction protein retinoblastoma. The beta(2)-adrenergic receptor agonist albuterol (100 nM) inhibited DNA synthesis after incubation with ASM for periods as brief as 1 h when these coincided with the timing of the restriction point. Inhibition of thrombin-stimulated DNA synthesis by albuterol (1-100 nM), 8-bromo-cAMP (300 microM), or prostaglandin E(2) (1 microM) was accompanied by a reduction in cyclin D1 protein levels. The ERK kinase inhibitor PD98059 (3-30 microM) attenuated thrombin-stimulated ERK phosphorylation and activity and the increase in cyclin D1 protein levels, as did albuterol (1-100 nM) or 8-bromo-cAMP (300 microM). In contrast, neither albuterol (100 nM) nor PD98059 (30 microM) reduced cyclin D1 mRNA levels between 4 and 20 h after thrombin addition, which suggests that elevation of cAMP regulates cyclin D1 by a post transcriptional mechanism. The proteasome inhibitor MG132 (30 and 100 nM) and the calpain I inhibitor N-acetyl-Leu-Leu-leucinal (10 microM) attenuated the reduction in thrombin-stimulated cyclin D1 levels in ASM exposed to albuterol (100 nM), 8-bromo-cAMP (300 microM), or the phosphodiesterase inhibitor isobutylmethylxanthine (100 microM). Thus, the cAMP-induced arrest of ASM in the G(1) phase of the cell cycle is associated with a proteasomal degradation of cyclin D1 protein and a reduced protein retinoblastoma phosphorylation that prevents passage through the restriction point.

Glucocorticoids inhibit proliferation, cyclin D1 expression, and retinoblastoma protein phosphorylation, but not activity of the extracellular-regulated kinases in human cultured airway smooth muscle.

We have previously shown that glucocorticoids inhibit mitogen-stimulated proliferation of human cultured airway smooth muscle (ASM) cells. The present study analyzed the effect of glucocorticoids on key regulatory pathways leading to passage of cells through the restriction point of the cell cycle, including those mediated by extracellular-regulated kinases (ERK) 1 and 2; the ERK upstream regulator MAPK kinase (MEK1); cyclin D1 levels; and levels and phosphorylation of retinoblastoma protein (pRb). Fluticasone propionate, a new inhaled glucocorticoid, was at least 10-fold more potent than dexamethasone in inhibiting thrombin-stimulated DNA synthesis and increases in cell number. Thrombin-stimulated increases in the levels and hyperphosphorylation of pRb were inhibited by glucocorticoids, which also reduced thrombin-stimulated cyclin D1 protein and messenger RNA (mRNA) levels. PD98059 (10 microM), an inhibitor of MEK1 activation, markedly attenuated thrombin stimulation of ERK activity and phosphorylation, DNA synthesis, and cyclin D1 levels. However, glucocorticoids had no effect on ERK activity or phosphorylation at 5 min, 2 h, or 12 h after addition of thrombin. In conclusion, glucocorticoid-induced reduction of cyclin D1 mRNA and protein levels, and of pRb phosphorylation, is sufficient to account for inhibition of ASM proliferation. Furthermore, these inhibitory effects of glucocorticoids on cyclin D1 and pRb occur on a component of the mitogen signaling cascade that is either downstream of or parallel to the ERK pathway.

Influence of hypoxia and glucose deprivation on tumour necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor expression in human cultured monocytes.

Ischaemia in wounds may modulate the expression of tumour necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF). The release of these and other cytokines by stimulated macrophages influences wound healing. Our aim was to examine the separate and combined effects of hypoxia and glucose deprivation on TNF-alpha and GM-CSF mRNA levels in human monocytes isolated from peripheral blood by density gradient centrifugation and purified by adherence. Cells were incubated for a 16-hour period in a hypoxic (3% O2) or normoxic (21% O2) environment in the presence or absence of glucose followed by a further 4 h under normoxic conditions in the presence or absence of lipopolysaccharide (LPS, 100 pg/ml). These different incubation conditions had no effect on cell viability, cell number, lactate dehydrogenase release or superoxide anion generation (n = 5, p > 0.05, paired t test). However, Northern hybridisation showed that hypoxia decreased the expression of GM-CSF mRNA in LPS-stimulated human monocytes by 46% (n = 9, p < 0.05, paired t test) and increased the expression of TNF-alpha by 102% (n = 7, p < 0.05, paired t test). The increase in the level of immunoreactive TNF-alpha in the cell supernatants paralleled the increase in TNF-alpha mRNA. The combination of glucose deprivation and hypoxia decreased the expression of both GM-CSF and TNF-alpha mRNA in LPS-stimulated human monocytes. Similarly, a decrease in the level of TNF-alpha in the cell supernatants was observed (n = 3-5, p < 0.05, two-way ANOVA). These data suggest that incubation conditions simulating ischaemia reduce LPS-induced cytokine expression.

Timing of administration of dexamethasone or the nitric oxide synthase inhibitor, nitro-L-arginine methyl ester, is critical for effective treatment of ischaemia-reperfusion injury to rat skeletal muscle.

1. The effects of the nitric oxide synthase (NOS) inhibitors, NG-nitro-L-arginine-methyl ester (L-NAME), nitroiminoethyl-L-ornithine and S. methylisothiourea on skeletal muscle survival following 2 h of tourniquet ischaemia and 24 h of reperfusion were compared with those of the anti-inflammatory steroid, dexamethasone. 2. Administration of each of the NOS inhibitors or dexamethasone 30 min before reperfusion reduced the degree of skeletal muscle necrosis 24 h after reperfusion. 3. The influence of timing of drug administration was investigated. L-NAME administered 30 min before reperfusion, at 3 h after reperfusion, but not thereafter, significantly improved muscle survival compared with saline-treated controls. Dexamethasone administered 30 min before, or at 3 or 8 h after reperfusion, but not at 16 h, significantly improved muscle survival, but neither agent had protective effects when administered before ischaemia. 4. After 8 h of reperfusion of ischaemic skeletal muscle, cell-free homogenates contained Ca(2+)-independent (inducible) NOS activity which was reduced in dexamethasone-treated (2.5 mg/kg) rats. Furthermore, inducible NOS mRNA levels, as detected by reverse transcriptase-PCR, were increased after 8 h of reperfusion in saline, but not in dexamethasone-treated rats. 5. These data suggest a significant deleterious effect of endogenous NO which may be restricted to the first 3 h of the reperfusion phase of ischaemia-reperfusion injury, and raise the possibility of effective treatment of incipient reperfusion injury, even after several hours of reperfusion.

Evaluation of corneal thickness and endothelial cells before and after excimer laser photorefractive keratectomy.

BACKGROUND: The possible endothelial damage induced by photorefractive keratectomy was investigated in myopic eyes. METHODS: A morphometric analysis of the endothelial cells was performed in 19 patients before and 2 months after photorefractive keratectomy for the correction of various degrees of myopia. Central ultrasonic pachometry was also recorded at the same examination times. RESULTS: No significant changes (p = .816) of the endothelial cell density were found between preoperative and postoperative measurements. The pleomorphic index did not show any significant changes after treatment (p = .955). Central corneal thickness was reduced to a various extent (range from 50 microns to 250 microns) according to the amount of myopic correction intended. CONCLUSIONS: Our preliminary data suggest that photorefractive keratectomy for the correction of myopia does not induce endothelial cell damage, at least in the short term.

Development and validation of a high-performance liquid chromatographic method for the determination of desmosines in tissues.

The development and the validation of a general strategy for the simple and accurate analysis of desmosines (isodesmosine and desmosine) in tissues coupled with the determination of collagen (as hydroxyproline) is described. The method is based on simplified sample (i.e., lung) pretreatment which involves, in a PTFE screw-capped Pyrex tube, homogenization, collagen extraction with hot 5% trichloroacetic acid and hydrolysis of the elastin-containing residue with 6 M hydrochloric acid, followed by cellulose minicolumn purification of desmosines from the hydrolysates, dansyl chloride pre-column derivatization of the purified desmosines and reversed-phase high-performance liquid chromatographic (HPLC) analysis of the dansyl derivatives using a Spherisorb ODS-2 column, an on-column enrichment sample device and a linear gradient of organic modifier (acetonitrile) in phosphate buffer. The simple sample pretreatment, the optimized chromatographic conditions and the short HPLC analysis time (less than 15 min) allow the accurate and rapid determination of desmosine and isodesmosine, thus permitting the determination of elastin in several kinds of tissues with a minimum of sample manipulation.