Inhalation of ZnO Nanoparticles: Splice Junction Expression and Alternative Splicing in Mice

Despite the wide application of nanomaterials, toxicity studies of nanoparticles (NP) are often limited to in vitro cell models, and the biological impact of NP exposure in mammals has not been thoroughly investigated. Zinc oxide (ZnO) NPs are commonly used in various consumer products. To evaluate the effects of the inhalation of ZnO NP in mice, we studied splice junction expression in the lungs as a proxy to gene expression changes analysis. Female ICR mice were treated with 6.46 × 104 and 1.93 × 106 NP/cm3 for 3 days and 3 months, respectively. An analysis of differential expression and alternative splicing events in 298 targets (splice junctions) of 68 genes involved in the processes relevant to the biological effects of ZnO NP was conducted using next-generation sequencing. Three days of exposure resulted in the upregulation of IL-6 and downregulation of BID, GSR, NF-kB2, PTGS2, SLC11A2, and TXNRD1 splice junction expression; 3 months of exposure increased the expression of splice junctions in ALDH3A1, APAF1, BID, CASP3, DHCR7, GCLC, GCLM, GSR, GSS, EHHADH, FAS, HMOX-1, IFNγ, NF-kB1, NQO-1, PTGS1, PTGS2, RAD51, RIPK2, SRXN1, TRAF6, and TXNRD1. Alternative splicing of TRAF6 and TXNRD1 was induced after 3 days of exposure to 1.93 × 106 NP/cm3. In summary, we observed changes of splice junction expression in genes involved in oxidative stress, apoptosis, immune response, inflammation, and DNA repair, as well as the induction of alternative splicing in genes associated with oxidative stress and inflammation. Our data indicate the potential negative biological effects of ZnO NP inhalation.

Inhaled Cadmium Oxide Nanoparticles: Their in Vivo Fate and Effect on Target Organs

The increasing amount of heavy metals used in manufacturing equivalently increases hazards of environmental pollution by industrial products such as cadmium oxide (CdO) nanoparticles. Here, we aimed to unravel the CdO nanoparticle destiny upon their entry into lungs by inhalations, with the main focus on the ultrastructural changes that the nanoparticles may cause to tissues of the primary and secondary target organs. We indeed found the CdO nanoparticles to be transported from the lungs into secondary target organs by blood. In lungs, inhaled CdO nanoparticles caused significant alterations in parenchyma tissue including hyperemia, enlarged pulmonary septa, congested capillaries, alveolar emphysema and small areas of atelectasis. Nanoparticles were observed in the cytoplasm of cells lining bronchioles, in the alveolar spaces as well as inside the membranous pneumocytes and in phagosomes of lung macrophages. Nanoparticles even penetrated through the membrane into some organelles including mitochondria and they also accumulated in the cytoplasmic vesicles. In livers, inhalation caused periportal inflammation and local hepatic necrosis. Only minor changes such as diffusely thickened filtration membrane with intramembranous electron dense deposits were observed in kidney. Taken together, inhaled CdO nanoparticles not only accumulated in lungs but they were also transported to other organs causing serious damage at tissue as well as cellular level.

Combined surgical and endovascular treatment of extensive thoracic aortic aneurysm

AIM

Patients with extensive aneurysm involving ascending aorta, aortic arch and descending aorta are usually treated by sequential operations. For these patients we can also use combined surgical and endovascular treatment. The experience with this procedure published in the literature is very limited. We report our experience in the ''elephant trunk'' technique followed by an endovascular stent-grafting of the descending thoracic aorta in a small group of three consecutive patients with extensive thoracic aortic aneurysm.

METHODS

Three consecutive patients with extensive thoracic aortic aneurysm or chronic dissection underwent combined surgical and endovascular treatment between January and December 2004. The procedure was carried out as a two-stage procedure. During the first stage aortic arch was replaced using the elephant-trunk'' method and during the second stage the stentgrafting of the descending aorta was performed.

RESULTS

All three patients were treated successfully. There was no death, no endoleak and no permanent neurological deficit. One patient had a transient paraparesis. In all patients the spiral CT demonstrated excellent technical result without endoleak and with thrombosis of the paraprosthetic space.

CONCLUSIONS

We can conclude, that the combined surgical and endovascular treatment of extensive thoracic aortic aneurysm is a feasible method which could reduce mortality and morbidity. In our institution the elephant trunk technique followed by an endovascular stent-grafting of the descending aorta is the preferred method of treatment in patients with extensive thoracic aortic aneurysm involving ascending aorta, aortic arch and descending aorta.

[Options for combining surgical and endovascular techniques in the management of large aneurysms and dissections of the thoracic aorta]

The surgical management of aneurysms and dissections of the thoracic aorta, as well as their endovascular management, all have their technical and medical limits. The aim of this work is to point out possibility for combination of the both treatment methods and to share our first practical experience with this procedure. The procedures conducted have been divided into the following groups: combined procedures, where the surgical part enables implantation of the stentgraft into the descending aorta or is managing imperfect results of such implantations, procedures, where combining the surgical and endovascular treatment lowers operational stress of the patient, as the extracorporeal circulation and the circulation arrest are not required, procedures, where advantages of both the surgical treatment in the region of the aortic arch and the endovascular treatment in the region of the descending aorta, are combined. Using the combination of both the surgical and endovascular techniques in the management of the large aneurysms and dissections of the thoracic aorta, appears to be a perspective method. The patient may benefit from its lower perioperative risk rates and lower postoperative morbidity rates. A good long-term effect of the above treatment method may be expected, however, it has to be verified in long-term patient studies.

Myocardial revascularisation in patients with severe left ventricular dysfunction. Early and midterm results

AIMS

This retrospective study evaluates early and midterm results in patients with severe left ventricular dysfunction.

TECHNIQUE

Ninety-seven consecutive patients with coronary artery disease and ejection fraction of left ventricle (LVEF) less or equal to 25 % underwent elective coronary artery bypass graft procedure between September 1998 and December 2001. Mean age at operation was 66 (47-86) years. The main symptoms were angina class III-IV Canadian Cardiovascular Society (CCS) in 78 patients (80 %) and dyspnoea class III-IV New York Heart Association (NYHA) in 43 patients (44 %). The major indications for surgery were severe angina, dyspnoea in 90 patients (93 %). Cardiac index (CI), echocardiography (ECHO), planimetry, end-diastolic pressure of left ventricle (LVEDP), end-diastolic diameter of left ventricle (LVEDd) were used to access left ventricular function preoperatively. ECHO was also used to access left ventricular function postoperatively.

RESULTS

Early postoperative (30 days) mortality was 4.1 %. Complications had 25 patients (26 %) postoperatively. Two years survival was 95.7 %. Class III-IV CCS and/or NYHA had 17 patients (17.5 %) two years after surgery. LVEF (assessed by ECHO) improved from 23.1 % preoperatively to 36.0 % postoperatively (p < 0.05).

CONCLUSION

The study showed that elective myocardial revascularisation in patients with severe left ventricular dysfunction and signs of myocardial viability is not necessarily associated with high operative mortality. It can be performed safely with respectable midterm survival in concordance with left ventricular function improvement, symptom relief and quality of life improvement.

[Reconstruction of the femoro-popliteal and peripheral portion in saphenous insufficiency]

Implantation of a venous bypass is the best method of infraarticular and crural reconstructions. In 30%, however, a suitable saphenous vein is not available. If on account of severe ischemia revascularization is necessary, an alternative method must be selected. From a total number of 326 peripheral reconstructions with a distal anastomosis into the distal popliteal artery or crural artery the authors had to use instead of a long venous bypass a subsidiary reconstruction in 145 patients (44.6%). The authors implanted composite venous bypasses in 36 patients (24%), in 93 patients (64%) they combined a venous bypass with desobliteration of the superficial femoral artery and in 16 patients (11%) with an artificial prosthesis. For the end-to-end anastomosis of the prosthesis and vein the authors suggested a plastic operation by means of a venous patch which makes a short anastomosis possible with a smooth transit from a wide prosthesis into a narrow vein. The authors assume that in future ever more frequently the combination prosthesis and vein in the shape of a jump bypass will be preferred to other reconstructive methods, as it is relatively simple and rapid. Their hitherto assembled experience with this methods is favourable.

[Surgical treatment of post-traumatic thrombosis of the inferior vena cava]

A 49-year-old man contracted a fracture of the 8th and 9th rib on the right side and developed after this injury thrombosis of the inferior vena cava in the renal and suprarenal portion and of both renal veins manifested clinically as nephrotic syndrome of obscure aetiology. Only detailed cavographic and CT examination revealed this thrombosis. Caval thrombectomy was performed according to Spencer's method because of concurrent phlebothrombosis of the left lower extremity. The patient is in a satisfactory condition with permanent Pelentan medication.

[Personal experience with the use of acute isovolemic hemodilution in vascular surgery]

The authors present their eight-year experience with acute isovolaemic haemodilution during operations on blood vessels in the aorto-femoro-popliteal region. They remind of basic physiological findings, present actual results, and based on their experience and data in the literature, they formulate the main principles of indications and implementation of haemodilution.

[Chemical lumbar sympathectomy]

After an account of historical facts the authors describe the technique of chemical lumbar sympathectomy. A 7.5% phenol solution in glycerol was used (7.5 ml). At the Surgical Clinic of the Institute for Postgraduate Medical Training of the Regional Hospital with Policlinic in Ostrava chemical lumbar sympathectomy was performed in 22 patients. No complications were observed during operation and during the postoperative period and in all patients the effect was favourable.

[Arteriovenous shunt--a prerequisite for long-term hemodialysis therapy]

The authors give an account of the experience of their department with the establishment of arteriovenous fistulae during the preparation of patients for a dialyzation transplantation programme. In the course of 13 years a total of 685 a-v shunts were made. The results in 60 patients are evaluated in detail. These patients were treated in 1989 in the chronic dialyzation programme of the Ostrava dialyzation unit, focused on long-term patency of the fistulae. The cumulative patency of shunts up to one year is 83.3%, the long-term patency is 73.3%.

Significance of pedal arch for femoropopliteal vein bypass patency

There are different opinions about the usefulness of preoperative arteriography. Therefore we resolved to show its importance for the distal runoff evaluation as well as for the indication and results of femoropopliteal vein bypasses. There were controlled 149 patients 1-5 years after femoropopliteal vein bypass implantations. Seventy six vein bypasses proved to be patent and seventy three were closed. The findings of preoperative arteriographies visualizating the whole arterial periphery, including the pedal arch arteries, were compared in both groups of patients. It was proved that the evaluation of the distal runoff by means of preoperative arteriography may be reliable and correct under condition of tibial and pedal arch arteries visualization. According to our experience, the preoperative arteriography can be performed in such a way to fulfil this indispensable condition. In rare case of preoperative arteriography repeated failure, it is the peroperative prebypass arteriography, which always is successful. In evaluating the distal runoff, there must be taken into consideration the whole arterial complex: tibial + pedal arch arteries. The patency of pedal arch seems to be more important than the number of patent tibial arteries. According to preoperative arteriographic findings, there is possible to distinguish three main types of distal runoff: (1) Sufficient runoff: whole pedal arch and 1-3 tibial arteries patent; (2) satisfactory runoff: partial pedal arch patency and 1-3 tibial arteries patent; (3) Unsufficient runoff: total pedal arch obliterations and 1-3 tibial arteries patency.