Subtalar joint kinematic correlations with footprint arch index in race walkers.

AIM: The aim of the paper was to analyze the relationship between footprint arch index and subtalar joint movement in race walkers. METHODS: Thirteen young, highly skilled race walkers volunteered to participate. We obtained dominant-foot footprints in a bipedal stance. The arch index was measured to classify arch height. We also conducted a photogrammetric video-3D study on a running track. The support phase was recorded while subjects race walked at their individual competition speed. We calculated 4 angle time series describing the ankle joint kinematics during the support phase. Five specific step instants were calculated for each angle and correlated with the arch index. Race walkers were grouped according to arch height to compare. We also correlated the arch index with the time in medial support, and time to change from lateral to medial support during the stance phase. RESULTS: In the calcaneal angle we found correlations with the footprint (r=0.81; P<0.01) and statistical differences when grouped (P<0.01). In this angle we also found a moderate-high correlation between footprint arch index and the time in medial support (r=0.77; P<0.01), and also in the time to change from lateral to medial support during the stance phase (r=-0.73; P<0.01). Data also show that the race walkers adopt a characteristic propulsion technique in the end of the support. No statistical differences were found in the rearfoot angle, which has been previously associated to specific injuries in running. CONCLUSION: In conclusion, race walkers with higher arches exhibit a more pronounced support with the lateral side of the foot and they do so for a longer time. Conversely, subjects with flatter feet support with the medial side of the foot. The footprint has been found to be a good predictor for the technique employed with respect to the medial and lateral strike of the foot reflected by the calcaneal angle. Coaches should keep this in mind from both performance and injury prevention viewpoints.

Pre-treatment with trimetazidine increases sarcolemmal mechanical resistance in reoxygenated myocytes.

OBJECTIVE: Cytoskeletal and sarcolemmal fragility secondary to anoxia may contribute to sarcolemmal rupture and cell death during reoxygenation of cardiomyocytes. This study investigated the influence of trimetazidine (TMZ), a drug with effects on lipid metabolism and cell membranes, on reoxygenation-induced sarcolemmal rupture. METHODS: Isolated adult rat myocytes were submitted to 60 min of metabolic inhibition and 5 min of hypo-osmotic reoxygenation to simulate reperfusion edema in situ. Cells were allocated to 3 groups of treatment: in one group, TMZ 100 mumol/l was added to both the metabolic inhibition and reoxygenation buffers (group TMZ); another group was submitted to the same treatment but cells had previously been incubated with TMZ 100 mumol/l for 3 h (group TMZ-Pre); a control group underwent metabolic inhibition and hypo-osmotic reoxygenation without any treatment. Cell morphology was monitored throughout the experiment and sarcolemmal integrity was assessed by quantification of LDH activity and trypan blue exclusion test. RESULTS: After 60 min of metabolic inhibition most cells (83.1 +/- 2%) presented rigor contracture without between-group differences. Reoxygenation resulted in hypercontracture of 84.2 +/- 2.3, 91.2 +/- 1.4 and 84.1 +/- 2.1% of cells in TMZ, TMZ-Pre and control groups, P = NS. The trypan blue exclusion test revealed a higher proportion of cells with sarcolemmal integrity in TMZ and TMZ-Pre groups than in controls (12.7 +/- 2.0, 10.0 +/- 1.5 and 6.3 +/- 0.8%, respectively, P = 0.002). No between-group differences in LDH activity in the extracellular medium were observed at the onset or at the end of metabolic inhibition. However, LDH release was significantly lower (P = 0.002) in the TMZ-Pre group (1.6 +/- 0.1 IU/1000 cells) than in the TMZ and control groups (1.9 +/- 0.2 and 2.2 +/- 0.1 IU/1000 cells). CONCLUSION: Preincubation of cardiomyocytes with TMZ does not prevent rigor contracture induced by metabolic inhibition or hypercontracture during subsequent reoxygenation, but does improve sarcolemmal resistance to reoxygenation-induced mechanical stress. This could help to explain the beneficial effect of TMZ on infarct size.

Effect of osmotic stress on sarcolemmal integrity of isolated cardiomyocytes following transient metabolic inhibition.

OBJECTIVE: Exposure to hypotonic medium induces sarcolemmal rupture in metabolically inhibited cardiomyocytes. This study investigated the effect of osmotic stress applied during reoxygenation and the possible cooperation between cell swelling and hypercontracture to produce sarcolemmal disruption. METHODS: Freshly isolated adult rat myocytes were submitted to 60 min of metabolic inhibition (NaCN 2 mM). Reoxygenation was simulated by changing to one of 3 inhibitor free buffers: (1) normo-osmotic (312 mOsm); (2) hypo-osmotic (80 mOsm); (3) low Na+ normo-osmotic (312 mOsm). The contribution of hypercontracture-induced reoxygenation on sarcolemmal rupture was investigated in myocytes submitted to hypo-osmotic reoxygenation in presence of 2,3-butanedione monoxime 30 mM, a blocker of contractility. Recovery from mechanical fragility was studied by exposing cells to hypotonic buffer 20 or 40 min after restoration of metabolic activity, in either presence or absence of 2,3-butanedione monoxime. Two control groups without metabolic inhibition were used. One was exposed to osmotic stress after 60 min incubation in control conditions, the other was induced to hypercontract by exposure to hypo-osmotic, high-calcium buffer. Cell viability was assessed by the Trypan blue test. RESULTS: Before any intervention 81.9(1.2)% of cells were rod-shaped. After 60 min of metabolic inhibition most cells developed rigor contracture and only 16.4(1.8)% remained rod-shaped. Restoration of metabolic activity induced hypercontracture of most cells with rigor independently of buffer osmolality. Cell viability, however, significantly differed among groups: only 25.9(4.4)% of cells reoxygenated with hypo-osmotic buffer were viable vs. 74.1(7.6)% in the normo-osmotic reoxygenation group, and 82.9(2.9)% in the control group. Addition of 2,3-butanedione monoxime 30 mM during hypo-osmotic reoxygenation prevented hypercontracture and preserved cell viability. Delaying osmotic stress 20 or 40 min after the onset of reoxygenation did not improve viability [19.3(3.9) and 34.9(1.3)%, respectively]. Contractile blockade with 2,3-butanedione monoxime during the first 20 or 40 min of reoxygenation was associated with a reduction in the number of hypercontracted cells after the removal of the inhibitor but did not increase the proportion of hypercontracted viable cells (25% and 27%, respectively). CONCLUSIONS: (1) Osmotic stress following transient metabolic inhibition produces sarcolemmal disruption, and this effect is not related to the low Na+ concentration present in the hypo-osmotic buffer; (2) reoxygenation-induced hypercontracture cooperates with cell swelling to produce sarcolemmal disruption; and (3) osmotic fragility persists for at least 40 min after restoration of metabolic activity.

L-Arginine administration prevents reperfusion-induced cardiomyocyte hypercontracture and reduces infarct size in the pig.

OBJECTIVE: Stimulation of cGMP synthesis protects cardiomyocytes against reoxygenation-induced hypercontracture. The purpose of this study was to determine whether L-arginine supplementation has a protective effect against reperfusion-induced hypercontracture and necrosis in the intact animal. METHODS: Twenty-four Large-White pigs were randomized to receive either 100 mg/kg of L-arginine i.v. or vehicle 10 min before 48 min of coronary occlusion and 2 h of reperfusion. Hemodynamic variables, coronary blood flow and myocardial segment length changes (piezoelectric crystals) were monitored. Postmortem studies included quantification of myocardium at risk (in vivo fluorescein), infarct size (triphenyltetrazolium reaction), myocardial myeloperoxidase activity and histological analysis. Systemic, coronary vein, and myocardial cGMP concentration were measured in additional animals. RESULTS: Administration of L-arginine had no significant effect in hemodynamics or coronary blood flow. During reperfusion, myocardial cGMP content was reduced in the LAD as compared to control myocardium (P=0.02). L-Arginine increased myocardial cGMP content and caused a transient increase in plasma cGMP concentration during the initial minutes of reperfusion (P=0.02). The reduction in end-diastolic segment length induced by reperfusion, reflecting hypercontracture, was less pronounced in the L-arginine group (P=0.02). Infarct size was smaller in pigs receiving L-arginine (47.9+/-7.2% of the area at risk) than in controls (62.9+/-4.9%, P=0.047). There were no differences between groups in leukocyte accumulation in reperfused myocardium (P=0.80). CONCLUSION: L-Arginine supplementation reduces myocardial necrosis secondary to in situ ischemia-reperfusion by a direct protective effect against myocyte hypercontracture.

Prevention of ischemic rigor contracture during coronary occlusion by inhibition of Na(+)-H+ exchange.

OBJECTIVE: To determine the effect of Na(+)-H+ exchange blockade on ischemic rigor contracture and reperfusion-induced hypercontracture. METHODS: Thirty-six pigs were submitted to 55 min of coronary occlusion and 5 h reperfusion. Myocardial segment length analysis with ultrasonic microcrystals was used to detect ischemic rigor (reduction in passive segment length change) and hypercontracture (reduction in end-diastolic length). RESULTS: Pretreatment with the new, highly selective Na(+)-H+ exchange inhibitor HOE642 before occlusion reduced ischemic rigor (P < 0.05), attenuated segment shrinkage (P < 0.05) during subsequent reperfusion, dramatically reduced infarct size (P < 0.0001) and attenuated arrhythmias (P < 0.01). Inhibition of Na(+)-H+ exchange only during reperfusion by means of direct intracoronary infusion of HOE642 into the area at risk prevented reperfusion arrhythmias but had no effect on final infarct size, while treatment with intravenous HOE642 immediately before reperfusion had no detectable effects. CONCLUSION: These results indicate that inhibition of Na(+)-H+ exchange during ischemia is necessary to limit myocardial necrosis secondary to transient coronary occlusion, and that this action could by mediated by a protective effect against ischemic contracture. Inhibition of Na(+)-H+ exchange only during reperfusion has a partial and transient beneficial effect, but only when the inhibitor reaches the area at risk before reflow.

Sodium/hydrogen exchanger inhibition reduces myocardial reperfusion edema after normothermic cardioplegia.

OBJECTIVE: The hypothesis was that Na+/H+ exchange occurring during normothermic cardioplegia contributes to the development of myocardial edema during subsequent reperfusion and impairs functional recovery. METHODS: Rat hearts were perfused in a Langendorff apparatus and submitted to 60 minutes of normothermic cardioplegia and 90 minutes of reperfusion. Hearts were allocated to one of four groups (n = 8): inhibition of Na+/H+ exchanger with HOE642 throughout the whole experiment (HOE group), only during cardioplegia (HOE-C) or during reperfusion (HOE-R), and a control group. RESULTS: In HOE and HOE-C groups, myocardial water content at the end of reperfusion was lower than in the HOE-R and control groups (526 +/- 19 and 533 +/- 18 ml/100 gm dry tissue vs 632 +/- 25 and 634 +/- 17 ml/100 gm dry tissue, respectively, p = 0.001), left ventricular end-diastolic pressure increased less after reperfusion (46.6 +/- 9.7 and 63.2 +/- 10.0 mm Hg vs 75.1 +/- 4.3 mm Hg and 85.7 +/- 8.9 mm Hg, respectively, p = 0.006), and recovery of left ventricular developed pressure was better (46.7% and 45.8% vs 4.5% and 9.8%, p = 0.048). Relative to the control group, total lactate dehydrogenase release during reperfusion was reduced by 80.2%, 69.3% and 36% in HOE, HOE-C, and HOE-R groups, respectively. CONCLUSION: Inhibition of the Na+/H+ exchange during normothermic cardioplegia reduces myocardial edema and necrosis during subsequent reperfusion, improving functional recovery. Inhibition of Na+/H+ exchange during reperfusion only has a much smaller effect.

Contraction band necrosis at the lateral borders of the area at risk in reperfused infarcts. Observations in a pig model of in situ coronary occlusion.

The aim of this study was to test the hypothesis that increased mechanical stress at the lateral borders of the area at risk may render this area more susceptible to ischaemia/reperfusion injury in the absence of collateral flow. The spatial distribution of myocardial necrosis within the territory of a transiently occluded left anterior descending coronary artery was investigated in 31 porcine hearts submitted to 48 min of coronary occlusion and 6 h of reperfusion. Immediately before excising the heart, the left anterior descending coronary artery was re-occluded and 10% fluorescein was injected in the left atrium. The area at risk was imaged by ultraviolet illumination of the myocardial slices, and the area of necrosis by incubation in triphenyltetrazolium chloride. The area at risk was divided in four sectors and an index of eccentricity was calculated as the percent of the area of necrosis located in the two lateral sectors of the area at risk. The area of contraction band necrosis was measured in whole heart histological sections. Infarcts were generally small, and were composed almost exclusively of contraction band necrosis. There was a good correlation between the extent of the area of contraction band necrosis and infarct size (r = 0.831, P < 0.0005). The area of necrosis had a patchy appearance and was predominantly distributed along the lateral borders of the area at risk. This eccentric distribution was more prominent in smaller infarcts, and the eccentricity index was inversely correlated with infarct size (r = -0.471, P = 0.007), suggesting that contraction band necrosis occurs first at the interface between control and reperfused myocardium in this model. These results are in agreement with a prominent role of mechanical factors in the genesis of myocardial necrosis during transient coronary occlusion.

Biopsychosocial profile of women with dyspareunia.

OBJECTIVE: To compare biopsychologic profiles of women with dyspareunia with a matched no-pain control sample, and to determine whether dyspareunia subtypes based on physical findings have different psychosocial profiles from matched controls. METHODS: One hundred and five women with dyspareunia and 105 matched no-pain control women underwent standard gynecologic examination, endovaginal ultrasound, and colposcopy. They also completed a structured interview inquiring about pain other than dyspareunia, sexual function, and history of abuse, the Brief Symptom Inventory, the Sexual Opinion Survey, and the Locke-Wallace Marital Adjustment Scale. RESULTS: In comparison with women who do not experience pain with intercourse, the dyspareunia sample was found to have more physical pathology on examination, and they reported more psychologic symptomatology, more negative attitudes toward sexuality, higher levels of impairment in sexual function, and lower levels of marital adjustment. They did not report more current or past physical or sexual abuse. However, when the undifferentiated dyspareunia sample was divided into subtypes based on physical findings from the gynecologic examinations, the pattern of significant differences from controls varied according to dyspareunia subtype. Elevated psychologic symptomatology and relationship maladjustment were confined to the subtype with no discernible physical findings who reported levels of sexual function not significantly different from matched controls. The vulvar vestibulitis subtype suffered the highest levels of sexual impairment, although this subtype was not characterized by higher levels of psychologic symptoms than controls. CONCLUSION: As an undifferentiated group, women with dyspareunia have more physical pathology, psychologic distress, sexual dysfunction, and relationship problems. However, this pattern of differences appears to vary depending on the presence and type of physical findings evident on examination. Dyspareunia is a heterogeneous disorder requiring comprehensive gynecologic and psychosocial assessment to determine differentiated treatment strategies.

Men with prostate cancer: influence of psychological factors on informational needs and decision making.

OBJECTIVES: Studies indicate that men with prostate cancer (MPC) adopt passive roles in cancer management; however, increasing public awareness of prostate cancer and advocacy by MPC and their allies suggest otherwise. This study looks at the information that is important to MPC; their preferred participation in decision making; and the influence of sociodemographic, disease, and psychological factors on information needs and decision preferences. METHOD: Consecutive men diagnosed with prostate cancer and attending two tertiary care cancer clinics completed questionnaires on information needs and decision preferences. Questions included demographic information, health and disease status, psychosocial functioning, optimism, and decisional preferences and information preferences for content, type, focus, format, and amount. RESULTS: Questionnaires were completed by 101 MPC. Their mean age was 70 years and most were married and well-educated. Over 70% wanted detailed information at all illness stages focusing on their disease, treatment, survival, self-care, and empowerment. Over 60% of MPC wanted shared decision making with their physician. Psychological variables were found to influence information needs but not involvement in decision making. CONCLUSION: These results represent a challenge to health-care providers for accomodating the informational needs and decision preferences of individual MPC.

[Effects of reoxygenation-induced osmotic edema on cell viability. Study using isolated myocytes]. / Efecto del edema osmótico durante la reoxigenación sobre la viabilidad celular. Estudio en el miocito aislado.

OBJECTIVE: To investigate the hypothesis that reperfusion edema may kill myocytes. METHODS: Adult Sprague-Dawley rat hearts were perfused with a calcium free dissociation buffer containing collagenase 0.03% in a Langedorff system. Intact cells were selected and myocytes were cultured in adherent pretreated dishes. After 3 hours, 80% of cells were rod-shaped. Anoxia was simulated by means of metabolic inhibition by adding NaCN 2 mM to the control media, and reoxygenation by substituting this media with one of the following media non containing NaCN: 1) normo-osmotic (312 mOsm); 2) hypoosmotic (80 mOsm); 3) normo-osmotic with low Na+ (312 mOsm). A group of cells was kept with control media without metabolic inhibition and then submitted to simulated reoxygenation with hypoosmotic media (control group). The number of rod, square and round-shaped cells was monitored, and cell viability was assessed after 5 min of reoxygenation by the Trypan blue test. RESULTS: After 60 min of metabolic inhibition there were no differences in the % of cells without hypercontracture among groups reoxygenated with normo-osmotic, hypoosmotic, low Na+ normo-osmotic and control media (84 +/- 16, 74 +/- 10, 76 +/- 14 and 90 +/- 6% respectively (p = NS). After 5 min of reoxygenation, these values decreased (p < 0.001) to 19 +/- 6, 11 +/- 9 and 13 +/- 3% (p = NS), respectively, in groups with normo-osmotic, hypoosmotic, and low Na+ normo-osmotic reoxygenation, but were not modified in the control group (78 +/- 4). The % of viable cells (Trypan negative) preserved after 5 min of reoxygenation was 67 +/- 29% in the group with normo-osmotic reoxygenation, 31 +/- 23% in the group with hypoosmotic reoxygenation, and 85 +/- 12% in the group with low Na+ normo-osmotic reoxygenation (p < 0.001). Exposing cells without metabolic inhibition to hypoosmotic media resulted in no significative reduction of cell viability. CONCLUSION: Hypoosmotic reoxygenation following prolonged metabolic inhibition may kill viable myocytes. This effect is not due to the low Na+ concentration in the hypoosmotic medium.

[CCND1 gene amplification in the adenoid cystic carcinoma of the minor salivary glands]. / Amplificación del gen de la ciclina D1 en los carcinomas adenoides quísticos de glándulas salivares menores.

OBJECTIVE: Adenoid cystic carcinoma (ACC) is a tumour of epithelial origin that represents the most common malignant neoplasm of the minor salivary glands. However, little is known about the genes involved in the development and progression of this tumour. Cyclin D1 gene (CCND1) plays a key role in the control of the cell cycle, and its amplification is described in numerous cancers. The aim of this study is to determine the amplification of the CCND1 gene in the ACC of the minor salivary glands. MATERIALS AND METHODS: A retrospective study was performed on 12 patients with ACC of the head and neck. The amplification of the CCND1 was determined using multiple PCR. RESULTS: Amplification of the CCND1 was found in 4 patients (33.3%). No correlation was found between CCND1 amplification and clinicopathological parameters, although disease-free survival was diminished in patients with amplification. DISCUSSION/CONCLUSIONS: Our study demonstrates for the first time the amplification of the CCND1 gene in ACC. We have found an amplification rate similar to others neoplasms. CCND1 amplification seems to be associated with a poorer prognosis in these tumours, although this needs to be confirmed in larger studies.

[Epidermal growth factor receptor gene amplification and E-cadherin expression in head and neck carcinomas]. / Amplificación del gen del receptor del factor de crecimiento epidérmico y expresión de la E-cadherina en los carcinomas de cabeza y cuello.

INTRODUCTION: The E-cadherin adhesion molecule is fundamentally involved in the maintenance of normal epithelial morphology and differentiation. The scattering and invasion of cancer cells induced by epidermal growth factor receptor (EGFR) activation has been suggested to be probably by affecting E-cadherin function. The aim of this study is to confirm whether EGFR amplification is related to E-cadherin expression in head and neck squamous cell carcinomas. MATERIAL AND METHODS: Fifty patients with head and neck squamous cell carcinoma were studied. EGFR amplification was analyzed by semiquantitative PCR. E-cadherin expressión was determined by immunohistochemistry. RESULTS: EGFR amplification was found in 9 cases (18%). E-cadherin expression was generally weaker in tumors than in adjacent normal epithelium. No relationship was found between EGFR amplification and E-cadherin expression. CONCLUSION: EGFR amplification did not affect the level of E-cadherin expression, suggesting a complementary role of both of these molecules in reduction of cellular adhesion in head and neck squamous cell carcinomas.

[CCND1 oncogene amplification and cellular DNA content in squamous cell carcinomas of the head and neck]. / Amplificación del oncogén CCND1 y contenido celular de ADN en los carcinomas epidermoides de cabeza y cuello.

Cyclin D1 protein (encoded by the CCND1 gene) contributes to the progression of the cell cycle in the G1/S checkpoint. Cyclin D1 overexpression (for instance as a consequence of CCND1 amplification) might result in loss of control over genetic damage at this point and in an accumulation of chromosomal aberrations. In this work we analyze whether CCND1 amplification is associated with a higher incidence of alterations in cellular DNA content. 31 squamous cell carcinomas of the head and neck were studied. CCND1 amplification was determined by polymerase chain reaction. Cellular DNA content was determined by flow cytometry. CCND1 amplification was found in 6 (19%) cases. Thirteen (42%) cases were diploid and 18 (58%) were aneuploid. Two (33%) of the 6 cases with CCND1 amplification were aneuploid compared with 16 (64%) of the cases without CCND1 amplification (P = 0.36). We conclude that CCND1 amplification is not associated to a higher incidence of chromosomal aberrations in squamous cell carcinomas of the head and neck.

[Relationship between the integration of human papillomavirus and loss of heterozygosity of the P53 gene in squamous cell carcinomas of the head and neck]. / Asociación entre la integración del virus del papiloma humano y la pérdida de heterozigosidad del gen p53 en los carcinomas epidermoides de cabeza y cuello.

Human papillomavirus integration in cellular DNA and loss of heterozygosity of P53 gene are both related with tumour formation process by promoting genomic instability that leads to DNA abnormalities accumulation. In order to analyze the relationship between both events, 26 squamous cell carcinomas of the head and neck were studied. HPV 16 and 6b DNA was detected by PCR in 8 cases (31%), whereas P53 loss of heterozygosity was present in 16 cases (61%). No correlation was found between both events and they were not related to clinical factors neither the prognosis. Consequently, HPV integration and loss of heterozygosity of P53 seem to act independently in the genesis of these tumours.

[Inactivation of p53 and amplification of cyclin D1 in squamous cell carcinomas of the head and neck]. / Inactivación de P53 y amplificación de la ciclina D1 en los carcinomas epidermoides de cabeza y cuello.

P53 and CCND1 (cyclin D1) genes play a critical role in the cell cycle regulation. Abnormalities of these genes are frequent in different types of cancers, including those of the head and neck. The aim of this work is to investigate whether P53 inactivation (determined by loss of heterozygosity analysis) is related to CCND1 gene amplification (determined by differential PCR analysis), and if these alterations are correlated with clinical outcome in a series of 56 patients with squamous cell carcinoma of the head and neck. Loss of heterozygosity of the P53 gene was found in 39 cases (70%) and CCND1 amplification in 17 cases (30%). Both abnormalities together were found in 11 cases (20%), without a significant association between them (P = 0.83). No relationship was found between P53 inactivation, the clinico-pathological parameters analyzed and the clinical outcome. CCND1 amplification was associated with advanced T-stages (P = 0.02), nodal metastases (P = 0.01) and a decreased survival (P = 0.002). The combination of both abnormalities shows a pattern that seems to be additive, since it was associated with an increase in tumor recurrences and a decrease in survival that was higher than for either of them individually. In conclusion, P53 and CCND1 abnormalities are frequent in squamous cell carcinomas of the head and neck. The combined analysis of these abnormalities seems to be more informative than either of them individually and may have a prognostic value in these carcinomas.

[Prognostic significance of the expression of adhesion molecules E-cadherin, Cd44s and CD44V6 in supraglottic squamous carcinoma]. / Significado pronóstico de la expresión de las moléculas de adhesión E-cadherina, CD44s y CD44V6 en los carcinomas epidermoides supraglóticos.

OBJECTIVE: To establish the prognostic significance of the expression of adhesion molecules E-cadherin, CD44s and CD44v6 in squamous cell carcinomas of the supraglottic larynx. MATERIAL AND METHODS: The expression of the studied molecules was determined by immunohistochemistry in paraffin-embedded tissue specimens from 101 patients. RESULTS: The expression of the three molecules was reduced in carcinomas compared to normal epithelium. The cases with recurrence showed an E-cadherin and CD44s expression significantly lower than those cases without recurrence. Reduced expression of any of the three molecules correlated with a decrease in survival, although the differences were not significant. In multivariate analysis only nodal stage (N) was an independent prognostic factor. CONCLUSIONS: Although reduced expression of E-cadherin, CD44s and CD44v6 seems to be related to a poor prognosis in supraglottic squamous cell carcinomas, these changes do not offer a useful adjunct to current prognostic indicators.

Defective sarcoplasmic reticulum-mitochondria calcium exchange in aged mouse myocardium.

Mitochondrial alterations are critically involved in increased vulnerability to disease during aging. We investigated the contribution of mitochondria-sarcoplasmic reticulum (SR) communication in cardiomyocyte functional alterations during aging. Heart function (echocardiography) and ATP/phosphocreatine (NMR spectroscopy) were preserved in hearts from old mice (>20 months) with respect to young mice (5-6 months). Mitochondrial membrane potential and resting O2 consumption were similar in mitochondria from young and old hearts. However, maximal ADP-stimulated O2 consumption was specifically reduced in interfibrillar mitochondria from aged hearts. Second generation proteomics disclosed an increased mitochondrial protein oxidation in advanced age. Because energy production and oxidative status are regulated by mitochondrial Ca2+, we investigated the effect of age on mitochondrial Ca2+ uptake. Although no age-dependent differences were found in Ca2+ uptake kinetics in isolated mitochondria, mitochondrial Ca2+ uptake secondary to SR Ca2+ release was significantly reduced in cardiomyocytes from old hearts, and this effect was associated with decreased NAD(P)H regeneration and increased mitochondrial ROS upon increased contractile activity. Immunofluorescence and proximity ligation assay identified the defective communication between mitochondrial voltage-dependent anion channel and SR ryanodine receptor (RyR) in cardiomyocytes from aged hearts associated with altered Ca2+ handling. Age-dependent alterations in SR Ca2+ transfer to mitochondria and in Ca2+ handling could be reproduced in cardiomyoctes from young hearts after interorganelle disruption with colchicine, at concentrations that had no effect in aged cardiomyocytes or isolated mitochondria. Thus, defective SR-mitochondria communication underlies inefficient interorganelle Ca2+ exchange that contributes to energy demand/supply mistmach and oxidative stress in the aged heart.

RNase1 prevents the damaging interplay between extracellular RNA and tumour necrosis factor-α in cardiac ischaemia/reperfusion injury.

Despite optimal therapy, the morbidity and mortality of patients presenting with an acute myocardial infarction (MI) remain significant, and the initial mechanistic trigger of myocardial "ischaemia/reperfusion (I/R) injury" remains greatly unexplained. Here we show that factors released from the damaged cardiac tissue itself, in particular extracellular RNA (eRNA) and tumour-necrosis-factor α (TNF-α), may dictate I/R injury. In an experimental in vivo mouse model of myocardial I/R as well as in the isolated I/R Langendorff-perfused rat heart, cardiomyocyte death was induced by eRNA and TNF-α. Moreover, TNF-α promoted further eRNA release especially under hypoxia, feeding a vicious cell damaging cycle during I/R with the massive production of oxygen radicals, mitochondrial obstruction, decrease in antioxidant enzymes and decline of cardiomyocyte functions. The administration of RNase1 significantly decreased myocardial infarction in both experimental models. This regimen allowed the reduction in cytokine release, normalisation of antioxidant enzymes as well as preservation of cardiac tissue. Thus, RNase1 administration provides a novel therapeutic regimen to interfere with the adverse eRNA-TNF-α interplay and significantly reduces or prevents the pathological outcome of ischaemic heart disease.