Interplay of endothelial and inducible nitric oxide synthases modulates the vascular response to ischaemia-reperfusion in the rabbit lung.

AIM: Lung ischaemia-reperfusion induces nitric oxide synthesis and reactive nitrogen species, decreasing nitric oxide bioavailability. We hypothesized that in the ventilated lung, this process begins during ischaemia and intensifies with reperfusion, contributing to ischaemia-reperfusion-induced pulmonary vasoconstriction. The aim was to determine whether ischaemia-reperfusion alters inducible and endothelial nitric oxide synthase expression/activity, reactive nitrogen species generation, and nitric oxide bioavailability, potentially affecting pulmonary perfusion. METHODS: Ischaemia-reperfusion was induced for various times in anesthetized rabbits with ventilated lungs by reversibly occluding the right pulmonary artery and initiating reperfusion. Nitric oxide synthase activity/expression and phosphorylation, reactive nitrogen species generation and total nitrate/nitrite were determined in lung tissue. RESULTS: Inducible nitric oxide synthase expression and activity, and reactive nitrogen species formation coincided with increased pulmonary vascular resistance during reperfusion and increased with ischaemia duration, further increasing after 2-h reperfusion. Total nitrate/nitrite also increased with ischaemia but decreased after 2-h reperfusion. Pre-treatment with an inducible nitric oxide synthase inhibitor (1400W; Cayman Chemical Company, Ann Arbor, MI, USA) attenuated inducible nitric oxide synthase activity, reactive nitrogen species generation and pulmonary vascular resistance, but did not affect total nitrate/nitrite. Endothelial nitric oxide synthase expression was unchanged by ischaemia-reperfusion; however, its phosphorylation on serine 1177 and dephosphorylation on threonine 495 was uncoupled, suggesting decreased endothelial nitric oxide synthase activity. 1400W prevented uncoupling of endothelial nitric oxide synthase phosphorylation, maintaining its activity during reperfusion. CONCLUSION: Ischaemia-reperfusion up-regulates inducible nitric oxide synthesis and/activity, which coincides with reduced endothelial nitric oxide synthase activity as suggested by its uncoupling and may contribute to ischaemia-reperfusion-induced pulmonary vasoconstriction.

Long-lasting involuntary motor activity after spinal cord injury.

STUDY DESIGN: The study design used is prospective cohort study. OBJECTIVES: This study was designed to neurophysiologically characterize spinal motor activity during recovery from spinal cord injury (SCI). SETTING: University of Louisville, Louisville, Kentucky, USA. METHODS: Twenty-five consecutive acute SCI admissions were recruited for this study. The American Spinal Injury Association Impairment Scale (AIS) was used to categorize injury level and severity at onset. Surface EMG recording was carried out initially between the day of admission and 17 days post-onset (6.0 ± 4.3, mean ± s.d. days). Follow-up recordings were performed for up to 9 months after injury. Initial AIS distribution was 7 AIS-A; 3 AIS-B; 2 AIS-C; 13 AIS-D. RESULTS: Twelve subjects (48%) showed long-duration involuntary motor-unit activation during relaxation. This activity was seen on initial examination in nine and on follow-up by 3 months post-injury in three others. It was seen in muscles innervated from the injury zone in 11 and caudal to the lesion in 9 subjects. This activity was independent of the presence or absence of tendon reflexes and the ability to volitionally suppress plantar stimulation elicited reflex withdrawal. CONCLUSION: The form of involuntary activity described here is the likely result of the altered balance of excitation and inhibition reaching spinal motor neurons because of the loss of inhibitory interneurons or their reduced activation by damaged supraspinal drive and the synaptic reorganization that follows SCI. As such, this activity may be useful for monitoring the effects of neuroprotective and restorative intervention strategies in persons with SCI.

Neurophysiological characterization of motor recovery in acute spinal cord injury.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: This study was designed to neurophysiologically characterize motor control recovery after spinal cord injury (SCI). SETTING: University of Louisville, Louisville, Kentucky, USA. MATERIAL: Eleven acute SCI admissions and five non-injured subjects were recruited for this study. METHODS: The American Spinal Injury Association Impairment Scale (AIS) was used to categorize injury level and severity at onset. Multimuscle surface electromyography (sEMG) recording protocol of reflex and volitional motor tasks was initially performed between the day of injury and 11 days post onset (6.4±3.6, mean±s.d. days). Follow-up data were recorded for up to 17 months after injury. Initial AIS distribution was as follows: 4 AIS-A; 2 AIS-C; 5 AIS-D. Multimuscle activation patterns were quantified from the sEMG amplitudes of selected muscles using a vector-based calculation that produces separate values for the magnitude and similarity of SCI test-subject patterns to those of non-injured subjects for each task. RESULTS: In SCI subjects, overall sEMG amplitudes were lower after SCI. Prime mover muscle voluntary recruitment was slower and multimuscle patterns were disrupted by SCI. Recovery occurred in 9 of the 11 subjects, showing an increase in sEMG amplitudes, more rapid prime mover muscle recruitment rates and the progressive normalization of the multimuscle activation patterns. The rate of increase was highly individualized, differing over time by limb and proximal or distal joint within each subject and across the SCI group. CONCLUSIONS: Recovery of voluntary motor function can be quantitatively tracked using neurophysiological methods in the domains of time and multimuscle motor unit activation.

Ciglitazone ameliorates homocysteine-mediated mitochondrial translocation and matrix metalloproteinase-9 activation in endothelial cells by inducing peroxisome proliferator activated receptor-gamma activity.

The activation of peroxisome proliferator activated receptor-gamma (PPARgamma) ameliorates the homocysteine (Hcy)-induced matrix metalloproteinase (MMP) by decreasing reactive oxygen species (ROS) production. However, the mechanism by which Hcy induces ROS generation and MMP activation is unclear. We hypothesize that Hcy increases NADH oxidase (Nox-4) and decreases thioredoxin (Trx). This leads to translocation of Nox-4 into the mitochondria and decrease in Trx. In addition, activation of PPARgamma ameliorates the translocation of Nox-4 into mitochondria and MMP-9 activation. Mouse aortic vascular endothelial cells (MVEC) were cultured in the presence or absence of 100 microM Hcy. The cells were pre-treated with ciglitazone (CZ, 150 microM). Activity of PPARgamma activity was measured by electrophoretic mobility shift assay (EMSA) and antibody super shift assay. In situ generation of ROS was measured using 2,7-dichlorofluorescin (DCF) as a probe. The expression of Nox-4 and Trx were measured by quantitative real-time polymerase chain reaction (Q-RT-PCR). The translocation of Nox-4 was measured by 2-D gel analysis. To determine the levels of Nox-4 and Trx, the mitochondria and cytosol were separated and Western blot analysis was preformed. The MMP-9 activity was measured by gelatin-zymography. The results suggested that CZ activated endothelial PPARgamma in the presence of Hcy. Production of ROS was ameliorated by PPARgamma activation. Expression of Nox-4 was increased, while production of Trx was decreased by Hcy. However, the treatment with CZ normalized the levels of Nox-4 and Trx. Nox-4 was translocated into mitochondria in Hcy-treated endothelial cells. This translocation was associated with decreased production of Trx in mitochondria. The treatment with CZ blocked this translocation and increased Trx levels in mitochondria. Hcy-mediated MMP-9 activity was decreased in cells pre-treated with CZ. These results suggest that Hcy increases NADH oxidase and decreases Trx by translocation of Nox-4 to mitochondria. The data show that indeed, activation of PPARgamma ameliorates the mitochondrial translocation of NOX-4 and MMP-9 activation.

[Surgical sepsis. II. Effectiveness of immune therapy with recombinant interleukin-2]. / Khirurgicheskii sepsis. Soobshchenie 2. Effektivnost' immunoterapii rekombinantnym interleikinom-2.

Two methods of administration of Roncoleukin were used as two subcutaneous injections in dose of 500,000 units with a 3 day interval and in the regimen of extracorporeal immunotherapy. The use of Roncoleukin resulted in the clinical improvement in 83% of patients and in the detoxicating and immunocorrecting effects in 77.3 and 60% respectively which was reliably different from analogous indices (33.4%, 45% and 7.5%) in the placebo group. Other values of the prognosed lethality being equal, the real 28-day lethality in the placebo group was 21.5%, while the using of Roncoleukin allowed the level of lethality of patients with surgical sepsis to become 3.8 times lower, including the subgroup of patients with severe sepsis from 50 to 13.6%. The trials performed showed the drug Roncoleukin to be endurable and not toxic and allowed to determine the indications and contraindications to using cytokin therapy in the complex treatment of pyo-septic diseases.

[Surgical sepsis. Part I. Immunologic markers of systemic inflammatory reaction]. / Khirurgicheskii sepsis. Chast' I. Immunologicheskie markery sistemnoi vospalitel'noi reaktsii.

The aim of the work was to develop accessible methods of laboratory diagnosis of the systemic inflammatory reaction, based on an assessment of biological (inflammatory and immunosuppressive) activity of serum of surgical sepsis patients (n = 104). The investigation has shown that surgical sepsis patients are characterized by marked immune dysfunctions, immunosuppressive bioactivity of blood serum being detected in most patients (in 65.6%) beginning from the earliest stages of the development of the sepsis process. It was found that in patients with dominating suppressive activity of serum the immune disturbances were more pronounced and in every second case they were of combined type. The authors propose to use the degree of the immunosuppressive potential of serum factors as the key classification sign determining the presence of CARS-positive or CARS-negative phenotype in such patients. The results obtained suggest that it is expedient for complex therapy of surgical sepsis to include immunocorrection aimed at the weakening of immunosuppresive action of antiinflammatory mediators and shift of the balance towards the reinforcement of activity of proinflammatory ones (IL-12, IL-1) and Th-1 cytokines (IL-2, IFN-g).

[Cytokines in the treatment of a generalized surgical infection]. / Tsitokiny v lechenii generalizovannoi khirurgicheskoi infektsii.

A novel approach to the treatment of surgical sepsis has been tried: cytokine-based immunotherapy. Human recombinant interleukin-2 (IL-2) and a mixture of native cytokines obtained by arteriovenous perfusion of xenospleen were used as a source of proinflammatory cytokines. Extracorporeal immunotherapy of 62 patients with surgical sepsis with mononuclear cells treated by autologous IL-2 resulted in a significant decrease of endotoxicosis and effective immunocorrection. Cytokine-based immunotherapy notably decreased the mortality of patients with generalized surgical infection--to 14.6%, which was lower than the expected mortality (35%) and the mortality in the control group (34.5%).

[Surgical treatment of chronic duodenal obstruction after radical operations on the stomach in peptic ulcer]. / Operativnoe lechenie khronicheskoi neprokhodimosti dvenadtsati- perstnoi kishki posle radika'lnykh operatsii na zheludke pri iazvennoi bolezni.

The authors operated on 138 patients with impaired duodenal patency after gastric resection and selective proximal vagotomy. The most substantiated operation is the Roux-en-Y reconstruction. In possible elimination of mechanical obstacles and normal tonicity of the duodenum, the passage through it was restored by means of isoperistaltic jejunal segment. Good long-term results were noted in 83.2%, satisfactory--in 13.6%, bad (ulcer recurrence)--in 3.2% of the patients.