Optical properties of copper helical nanostructures: the effect of thickness on the SPR peak position.

In this study, we have investigated the effect of thickness on the structural and optical properties of copper (Cu) helical nanostructures. Thin films with thicknesses of 160 nm, 280 nm, 450 nm, and 780 nm were obtained by e-beam glancing angle deposition. The morphology and the microstructure were studied by field emission scanning electron microscopy, x-ray diffraction and transmission electron microscopy, while for the optical analysis measurements spectroscopic ellipsometry was used. The results show that the deposited structures are porous with nanometer-sized crystallites preferentially oriented along (111) planes, as well as that the diameter of the helices increases with thickness. Detailed analyses of optical properties have demonstrated that the dielectric function of Cu structures is greatly influenced by the films thicknesses. With increasing thickness from 160 nm to 780 nm, the surface plasmon resonance peak was shifted from 1.31 eV to 1.05 eV, which was correlated with the growth mechanism and the size of deposited nanostructures.

Investigation of properties of electrochemically synthesized iron oxide nano-powders.

Nano-sized powders of iron oxides have been synthesized electrochemically at temperatures in the range of 295-361 K, and current densities in the range of 200-1000 mA dm(-2). The structure and morphology of the powders were investigated by X-ray diffraction and scanning electron and transmission electron microscopy techniques. Their infrared absorption spectra, specific heat C(p)(T) and magnetic susceptibility chi(T) temperature dependences are also determined. The obtained powders consist of two phases, each possessing distinguished characteristics: the one formed of large plates and the other of whiskers. By appropriate adjustment of the synthesis conditions, it is possible to change features and relative abundances of the two phases, and that way to control morphology and other powder properties. Relaxation and transformation of the phases under external influences was also investigated, and the optimal procedure for preparation and stabilization of iron oxide nano-sized powders with desired characteristics was established.

The effects of beta-estradiol on SHSY5Y neuroblastoma cells during heavy metal induced oxidative stress, neurotoxicity and beta-amyloid secretion.

The role of estrogen as a neurotrophic/neuroprotective agent in neurodegenerative diseases such as Alzheimer's and Parkinson's diseases is increasingly being shown. In this study we examine the neuroprotective effects of beta-estradiol on SHSY5Y neuroblastoma cells which have been exposed to the heavy metals cobalt and mercury. The results show that cobalt and mercury are able to induce oxidative stress and cell cytotoxicity and increase the secretion of beta-amyloid 1-40 and 1-42. These deleterious effects are reversed by the pretreatment of cells with beta-estradiol. It is further shown that beta-estradiol exerts its neuroprotective action through mechanisms which reduce oxidative stress and reduce beta-amyloid secretion. Pre-treatment of the cells with alpha-estradiol did not alleviate the toxic effects of the heavy metals. Our results are significant as they contribute to a better understanding of the mode of action of estrogen with relevance to its use in the treatment of neurodegenerative disorders.

[Transposition of the gracilis muscle in reconstruction of the anal sphincter]. / Transpozicija m. gracilis-a u rekonstrukciji sfinktera anusa.

UNLABELLED: Fecal incontinence is a serious psychological and social problem for the patient, frequently leading to social isolation, loss of working potential and depression. Different static and dynamic methods for the reconstruction of anal sphincter are used in the surgical treatment of the incontinence. At the Clinic for Plastic Surgery and Burns, at the Military Medical Academy, we have been using the method of transposition of the gracilis muscle, previously described by Pickerill-Broadbent (1952) since 1970. The aim of this paper was to describe our results in the treatment of fecal incontinence with the gracilis muscle. We have operated on 14 patients: 5 with congenital absence of the anus, 2 with myelomeningocele, 2 with the teratoma in the sacral region, 2 with the injury after the surgical procedure in the anal region and 3 with war injuries in the perineal area. After the detailed clinical and neurological examinations and pre-surgical preparations, we have performed the operation using the already mentioned technique (Pickerill). The following postoperative complications were identified: one hematoma and two minor dehiscences of the perianal wounds that healed per secundam. The electrostimulations of the transposed gracilis muscle were performed postoperatively. All the operated patients have been followed up for three years after the operation. In 9 patients the result was estimated as the excellent, in 3 as affordable and in 2 as the poor (occasionally, they could not contain the liquid fecal incontinence)? CONCLUSION: Due to its anatomical characteristics, the gracilis muscle is the most suitable for the reconstruction of the anal sphincter. If the correct indication is made, and if the surgery is well prepared and technically performed, with the maximal protection of neurovascular pedicle, an excellent postoperative result can be expected in over 60% cases.

[Importance of adequate immobilization of the upper extremity in using the vascularized fibular graft]. / Znacaj adekvatne imobilizacije gornjeg ekstremiteta kod primene vaskularizovanog fibularnog grafta.

The most complications in patients after the reconstruction of the bone defect of the upper extremities are the fractures of the bone graft and pseudoarthrosis on one of the graft suture with defects of humerus. These complications influence on the primary efficiency of the reconstruction and prolong the recovery period. We registered five fractures, four pseudoarthrosis and two graft angulations in the prospective study on 25 patients where the defect of humerus, radius and ulna was compensated by the vascularized fibular graft. The analysis showed four fractures on the distal part of the reconstructed humerus graft and three pseudoarthrosis on the proximal part of reconstructed ulna. All osteogenic complications, apart from angulations which did not require additional interventions were solved by spongyoplasty according to Phemisters and more efficient postoperative immobilization.

[Complications in the use of vascularized fibular grafts: classification and treatment]. / Komplikacije u primeni vaskularizovanog fibularnog grafta: klasifikacija i resavanje.

The complications in the reconstruction of the diaphysed defects by the use of VFG or VOSKFG are not shown in the literature coherent so it is very difficult to compare and use showed results. For the compensation of the bone defects the specific complications could be differentiated according to the influence on the primary and overall efficiency of the reconstruction. The classification of the complications in the donors region and osteogenic and vascular complications in the recipients region was suggested in the analysis which encompassed all these divisions.

[Reconstructive methods in the treatment of soft tissue defects below the knee]. / Reconstruktivne metode u zbrinjavanjudefekata mekih tkiva potkolenice.

The specificity of the lower leg is in sparse collateral blood flow of the skin cover in the middle and distal part, reduced subcutaneous tissue and the prominence of the front side of tibia immediately under the skin. These characteristics of the lower leg make the application of the standard plastic reconstructive principles, which have been applied in the other regions of the body to a certain degree impossible. The progress of anatomical knowledge in relation to vascularization of the tissue territories--angiosoma, and the anatomy of the vascular skin system of the lower leg, along with the technological progress represented by the application of the surgical microscope, new surgical instruments and suture materials, provides the reconstructive surgeon, not only with classic but also with the modern surgical methods in this region: microvascular transplantation of the tissue and the application of the fasciocutaneous reversible flaps. The aim of this study was to show the available reconstructive methods in the treatment of the lower leg soft tissue and to analyze its application in the management of war wounds in the injured from the civil war in the former Yugoslavia. On the basis of our experiences in the management of war wounds, especially of the lower leg with the tissue defects, we would like to point on the existence of the clear indications for the application of certain reconstructive methods depending on the size, localization and tissue defect structure, as well as the advantages and disadvantages of the available reconstructive procedures.

[Vascularized fibular grafts in the reconstruction of bone defects caused by war injuries]. / Vaskularizovani fibularni graft u rekonstrukciji kostanih defekata nastalih ratnim ranjevanjem.

The efficiency of the vascularized fibular graft application in the reconstruction of diaphyseal defects of the long bone of extremities caused by war injuries was prospectively investigated in the group of 33 patients in the period 1991-1996, during the war in the former Yugoslavia. The preoperative, intraoperative and postoperative procedures were systematized. Early and late complications in donor and recipient regions were shown. The primary success was 63.6% and the total one was 93.9%. The efficiency of the vascularized fibular graft in the treatment of bone defects caused by war injuries could be compared with bone defects caused by trauma or by resection of malignant tumors.

[Frequency, etiology, localization and surgical treatment of war injuries with tissue defects]. / Ucestalost, etiologija, lokalizacija i hirursko lecenje ratnih rana sa defektima tkiva.

The retrospective analysis of 1,514 cases treated at the Clinic for Plastic Surgery and Burns of the Military Medical Academy in the period between 1991 and 1995, established that the percentage of the injuries caused by gunshots and those caused by explosives during the conflict in former Yugoslavia, was more or less the same. The injuries caused by gunshot more often occurred on the head, neck, arms and trunk. The injuries of the legs caused by the explosives were more frequent, and they occurred in 83% of the cases. All the plastic surgeons who took part in the treatment of patients and in preparing the surgeons of other specialties for the treatment applied the original classification of the war injuries according to the structure of the defects that had occurred, to standardize the approach to the planning of treatment and the treatment itself of the wounded. In the delayed primary or secondary treatment of the injuries with the tissue defects all known plastic and reconstructive methods were applied. In the cases requiring the covering of the the tissue defect with the full thickness skin, local skin, fasciocutaneous, fascioadipose or muscle flap was chosen. Distant pedicled direct flaps were used in cases when it was not possible to use a more suitable reconstructive method. Free skin, myocutaneous or complex microvascular flaps were applied in cases of more extensive defects or if a more suitable solution could not be found. Our experience in surgical treatment of war injuries with skin defects during the civil war in former Yugoslavia has shown that over 50% of all the injured patients required the treatment of a plastic surgeon in a definite surgical treatment of a war injury. A multidisciplinary approach is necessary in the majority of the injured, and the surgical team is composed according to the affected area and the extent of the injury.

[Sebaceous gland function in transplanted microvascular flaps]. / Funkcija lojnih zlezda transplantovanih mikrovaskularnih resnjeva.

Sebaceous glands produce sebum that contains: triglycerides, esters of cholesterol, and sometimes even pure cholesterol, squalene and esters of wax. Microvascular transplantation exposed the tissue of free flaps to the temporary ischemia and anaerobic metabolism, inflammatory, denervative and reinnervative processes. The sebaceous glands of the free flaps were also exposed to the action of physiopathologic processes during the micro vascular transfer. Because of that, the function of the sebaceous glands of the transplanted free flaps was estimated compared to the function of the sebaceous glands of the recipients and donor's region environment. The investigation of the sebaceous glands of free flaps function has been performed in 32 wounded patients at the Clinic for Plastic Surgery and Burns, and Institute for Medical Biochemistry of the Military Medical Academy. All the wounded have undergone the microvascular transplantation of the cutaneous, myocutaneous and osteocutaneous flaps. Dry residue in either of the soluble substances was measured in the period from six to thirty six months after the transplantation. The obtained results indicated that the function of the sebaceous glands of the transferred flaps 25.36 months after the transplantation was weaker than the function of the sebaceous glands of the recipients and donor's region's environment and amounted to 98% of the function of the sebaceous glands of the recipient is region's environment.

[Temperature of the skin in microvascular flaps]. / Temperatura koze mikrovaskularnih reznjeva.

Transferred free flaps by their defined vascular net improve the perfusion of the recipient region. Skin temperature depends on the skin perfusion, temperature conduction of the visceral organs, muscles and blood vessels, as well as on the heat loss by the evaporation and air convection in the environment. At the Clinic for Plastic Surgery and Burns and at the Institute of Hygiene of the Military Medical Academy, skin temperature of the transferred free flaps and the recipient region surrounding were analyzed and measured in controlled microclimate conditions. The analysis was performed in 31 subjects, 20.23 months after the free tissue transfer. The aim of the study was to determine the differences between the skin temperature of the transferred free flaps and the recipient region surrounding, as wall as of the donor's region surrounding. The results of the investigation revealed that skin temperature of the transferred free flaps was lower in 28 (90.3%) patients than the temperature of the donor's region surrounding. Skin temperature of the transferred free flaps was higher in 25 subjects (80.6%) than the temperature of the recipient region surrounding. Skin temperature of free flaps transferred to the foot and the lower leg was higher than the skin temperature of the recipient region surrounding but was also lower in the flaps transferred on the head. The temperature of the recipient region surrounding influenced the skin temperature of the transferred free flaps, besides the flap tissue perfusion.

[Reconstruction of the long bones and mandible with vascularized fibular grafts]. / Nadoknada defekata dugih kostiju i mandibule vaskularizovanim fibularnim graftom.

In two prospective studies at the Clinic for Plastic Surgery and Burns and Clinic for Maxillofacial Surgery of the Military Medical Academy in the period from 1991 to 1996 we performed 47 transplantations of the vascularized fibular graft in order to compensate bone defects of the long bones and mandibular inflicted by war wounding. The importance of the length of the vascular pedicle preparation for the total success was pointed out as well as the immobilization of the elbow region for the compensation of the defects of the upper arm and forearm and total healing of the mandibular for the later functional rehabilitation. The realized primary efficiency of 70.2% and total successfulness of 93.6% indicated that at the compensation on of bone defects the etiology of war wound could be compared to the etiology of malignant tumors resection and trauma.

[Use of Bernard's diadynamic current in evaluating recovery of pain sensitivity in transplanted microvascular flaps]. / Primena Bernardovih dijadinamickih struja u proceni oporavka sensibilnosti za bol u transplantovanim mikrovaskularnim reznjevima.

The application of microvascular transfer of tissues provides a single act transplantation of free flaps to any part of the body. Following the operation, free flaps are nerveless. By spreading out of nerves from the recipient region surrounding into the flap tissue, transplanted free flaps become reinervated. The sensitivity of the transferred free flaps is very important in feet, palms, breasts, genitals, face etc. The aim of our research was to use Bernard's diadynamic currents in establishing the time needed for recovery of the transferred flap's pain sensitivity in comparison with the recipient region's surrounding. At the Clinic for Plastic Surgery and Burns and Clinic for Physical Medicine and Rehabilitation of the Military Medical Academy, we used Bernard's-diadynamic current to analyze the recovery of the pain sensitivity in 33 patients with transferred free flaps. The first tests were performed six moths after the free flap transfer and were repeated in the intervals of 6 to 36 months. The pain recovery was tested in 5 cutaneous, 18 myocutaneous and 10 osteocutaneous flaps transplanted to foot-10, lower leg-13 and head-10. Pain sensitivity in the transferred flaps was detected 6 months after the free flaps transfer and was definitely ascertained 12 months after the operation. Current of 10.11 mA was required to reach the pain sensitivity threshold after the first six months and 8.52 mA after 36 months. It is obvious that the pain sensitivity threshold is significantly higher in the transferred free flaps (p < 0.001) than in the donor or recipient regions' surroundings.

Vascularized fibular graft in the reconstruction of posttraumatic mandibular defects.

The results of the use of the vascularized fibular graft for the reconstruction of posttraumatic defects of the mandible are presented. Different surgical procedures were applied in reconstruction of the mandibular defects in 120 wounded. In the last four years vascularized fibular graft was used in 11 mandibular reconstructions. Taking into account the survival rate of 100%, long vascular pedicle, strength, length and the possibilities of adaptation of the bone make this graft suitable for mandibular reconstruction. The functional and esthetic results obtained by the use of this graft were satisfactory, with minimal donor site morbidity.

Common bile duct pressure changes after fentanyl, morphine, meperidine, butorphanol, and naloxone.

Five groups of 10 patients received thiamylal, enflurane, nitrous oxide-oxygen anesthesia for elective cholecystectomy. The common bile duct was intubated via the cystic duct with a 16-g plastic catheter, and the control intraductal pressure was measured. Patients then were given equi-analgesic doses of fentanyl, morphine, meperidine, butorphanol, or placebo intravenously, and the common bile duct pressure was recorded for 20 min. Fentanyl, morphine, and meperidine significantly increased pressure in the common duct (P less than 0.001). Butorphanol produced only insignificant changes. Naloxone given 20 min later significantly (P less than 0.001) decreased pressure in patients given fentanyl, morphine, and meperidine. Naloxone given without narcotics caused an increase in pressure that, although statistically significant (P less than 0.03), was clinically insignificant. In five additional patients anesthetized with thiamylal, nitrous oxide-oxygen and intermittent doses of fentanyl, common bile duct pressures were normal.

Prevention of succinylcholine induced hyperkalemia by neurolept anesthesia and hexafluorenium in anephric patients.

Forty patients, half of them with normal kidney function, the other half anephric were included in the study. All received diphenhydramine, meperidine and atropine for premedication and droperidol, fentanyl, N2O and O2 for anesthesia. For endotracheal intubation and further relaxation 0.3 mg/kg hexafluorenium, followed in 5 minutes by 0.2 mg/kg succinylcholine were given intravenously. Anesthesia was maintained by 0.5 micrograms/kg increments of fentanyl, muscle relaxation by increments of 0.15 mg/kg or less hexafluorenium and 0.2 mg/kg or less succinylcholine, depending on the surgical time requirements. The drop in serum potassium concentration was sustained and similar in both groups. In the anephric group the drop after induction of neurolept anesthesia was statistically significant. The concentration remained low in both groups over the entire observation period. Unchanged serum sodium excluded hemodilution and the fact that there was no significant change in PvCO2 and pH mitigates against alkalosis as the cause for the observed drop. The anesthesia and muscle relation, as described, appears to be a suitable and hazard free alternative to other techniques.