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J Malina

Publications and source records attributed to J Malina.

At least 37 records · Page 2Linked to original sources
PubMed1998

Late aortic arch perforation by graft-anchoring stent: complication of endovascular thoracic aneurysm exclusion.

PURPOSE: To describe a fatal case of late aortic perforation by an endograft-anchoring stent. METHODS AND RESULTS: A 69-year-old woman presented 2 years after thoracoabdominal aneurysm repair with a 9-cm dilatation of the descending thoracic aorta proximal to the conventional aortic graft. A 38-mm Dacron graft with multiple Gianturco Z-stents sutured inside was placed transluminally across the aortic arch such that part of the uncovered portion of the proximal stent was partially across the left subclavian orifice. Four months later, the patient died from massive hemorrhage. Autopsy showed that the uncovered portion of the proximal stent had perforated the aortic arch. CONCLUSIONS: This case stresses the need for low-profile stent-grafts and smaller, more flexible introducer systems. Anchoring stents must be flexible, less traumatic, and strong enough to create a watertight seal even in tortuous vessels. To avoid aortic arch damage by thoracic stent-grafts, the proximal stent should be fully covered by the fabric.

Aged↗
PubMed1998

Endovascular AAA exclusion: will stents with hooks and barbs prevent stent-graft migration?

PURPOSE: To investigate if stents with hooks and barbs will improve stent-graft fixation in the abdominal aorta. METHODS: Sixteen- to 24-mm-diameter Dacron grafts were deployed inside cadaveric aortas. The grafts were anchored by stents as in endovascular abdominal aortic aneurysm repair. One hundred thirty-seven stent-graft deployments were carried out with modified self-expanding Z-stents with (A) no hooks and barbs (n = 75), (B) 4 5-mm-long hooks and barbs (n = 39), (C) 8 10-mm-long, strengthened hooks and barbs (n = 19), or (D) hooks only (n = 4). Increasing longitudinal traction was applied to determine the displacement force needed to extract the stent-grafts. The radial force of the stents was measured and correlated to the displacement force. RESULTS: The median (interquartile range) displacement force needed to extract grafts anchored by stent A was 2.5 N (2.0 to 3.4), stent B 7.8 N (7.4 to 10.8), and stent C 22.5 N (17.1 to 27.9), p < 0.001. Both hooks and barbs added anchoring strength. During traction, the weaker barbs were distorted or caused intimal tears. The stronger barbs engaged the entire aortic wall. The radial force of the stents had no impact on fixation, while aortic calcification and graft oversizing had marginal effects. CONCLUSIONS: Stent barbs and hooks increased the fixation of stent-grafts tenfold, while the radial force of stents had no impact. These data may prove important in future endograft development to prevent stent-graft migration after aneurysm exclusion.

Aged↗
PubMed1997

[Laparoscopic cholecystectomy and its safety--observations after 2000 procedures].

The authors experience with laparoscopic cholecystectomy in the group of 2200 patients operated on from March 1992 to September 1996 is discussed. The complications rate at the beginning and at the end of the study is expressed. In the last 100 cases there was conversion rate of 1%, no biliary injury was observed and the average postoperative hospital stay was 2.26 days. In the whole group of patients biliary injuries were observed in 0.18%. Lethality was 0.13%. The authors conclude, that laparoscopic cholecystectomy is a save method in the treatment of the gallstone disease, when certain rules are respected.

Cholecystectomy, Laparoscopic↗
PubMed1996

[Reoperation in laparoscopic procedures].

Besides of really positives bring laparoscopic procedures also complications, which sometimes demand reoperation. When in our literature nobody mentioned this topics the authors bring their own experiences with reoperations after laparoscopic procedures. The authors in time from March 1992 to November 1995 performed together 1836 laparoscopic operations. 19 times, it means in 1.03%, the reoperations was needed. In the paper the authors discuss the causes of the reoperations, possibilities and methods of complications solution. They also discuss possibilities of complications prevention. The open surgery was performed in lesions of biliary tree, in pancreatitis, peritonitis and duodenal lesion. This type of surgery was performed also in hernia repair after technical error. Laparoscopic reoperations were performed in haemorrhage from the gallbladder bed, in pritonitis and in recurrent inquinal hernia. There is to be said, that laparoscopic reoperations need experience in this technique. In euphory from the growing laparoscopic surgery there is the need to remark also complications and unsuccesses. With gaining experiences it is possible to perform also reoperations laparoscopically. It is important to be sufficiently aggressive in diagnostic procedures and also in therapy of complications. It is advisable to use diagnostic laparoscopy with adequate solution of situations. Keeping this all in mind, there is possible to minimise the sequelae of complications and reoperations. There is also the possibility to prevent the reoperations.

Humans↗
PubMed1994

[The importance and role of laparoscopic appendectomy].

Inspite of earlier beginning the laparoscopic appendectomy is in the shadow of laparoscopic cholecystectomy. In connection with laparoscopic appendectomy some problems are discussed--his significance or substantiality, techniques, advantages or disadvantages in contrast to classical appendectomy. The authors discussed these questions on the base of their own experiences with 56 laparoscopic appendectomies. These were done from 21. October 1992 to 7. February 1994. Known advantages of laparoscopic procedures are expressed--shorter hospital stay after the operation (in average 2.3 days), better view in the operating field with possibility of the treatment of gynecological pathology. Technical aspects are also discussed. The equipment with staplers according their opinion is needed. The time of the operations--average 44 minutes--is acceptable. The complication and conversion rate, which were noted in 3.6% resp. 5.3%, is quite good. There is a possibility to lower these numbers with increasing experience. The possibility for training in the laparoscopic field is great opportunity especially for young surgeons. In the end there is stated, that the authors consider laparoscopic appendectomy as an important step to the advanced procedures. The broad acceptance is recommended.

Adolescent↗
PubMed1992

Helospectin-like immunoreactivity in the esophagus.

Helospectin I and II are two non-amidated, VIP-like peptides, isolated from the salivary gland venom of the lizard Heloderma horridum. The lower esophagus of cat, sheep and man was analyzed for helospectin-like immunoreactivity. Immunocytochemistry revealed helospectin-immunoreactive nerve fibers in the muscle layers, submucosa and mucosa of all species studied. In myenteric ganglia helospectin-immunoreactive nerve fibers and nerve cell bodies could be seen. Double immunostaining for helospectin and vasoactive intestinal peptide (VIP) revealed their coexistence in nerve fibers and cell bodies throughout the lower esophagus of all species tested. Double immunostaining for helospectin and neuropeptide Y revealed their coexistence in nerve fibres surrounding vascular and non-vascular smooth muscle. In the cat and sheep (but not in man) a subpopulation of the helospectin/VIP-containing fibers stored, in addition, substance P. The helospectin-immunoreactive material in the esophagus probably constitutes a novel neuropeptide. The distribution of the VIP/helospectin-immunoreactive neurons and fibers indicates their possible involvement in the regulation of motor and secretory activities.

Animals↗
PubMed1992

Bacterial infection modulated by glucan: a search for the host defense potentiation mechanisms.

Interactions between bacteria and the host were studied from day 0 up to day 10 post-challenge in mice pretreated with soluble glucan (20 mg/kg i.p.) and challenged supralaryngeally with a virulent strain of Klebsiella pneumoniae. In the initial phase of infection, clearance of bacteria in the airways of glucan-treated mice was improved to an extent comparable with the vaccinated group but, in contrast to the immunized animals, subsequent regrowth of the bacterial inoculum was not prevented. The efficacy of defense, based during the entire course of infection mainly upon phagocytosis by neutrophils, markedly increased at intervals corresponding to the onset of humoral immune response. No evidence was obtained to indicate an enhanced involvement of alveolar macrophages in the phagocytosis of bacteria in glucan-stimulated mice. The results further support the notion that improvement of specific immune responsiveness rather than activation of nonspecific effector functions might be the most important expression of the host-defense-potentiating capacity of glucan and related stimulants of microbial origin.

Animals↗
PubMed1991

Informative value of a mouse model of Klebsiella pneumoniae infection used as a host-resistance assay.

To obtain a host-resistance assay (HRA) for quantitative evaluation of immunostimulatory effects of various substances, an experimental model of K. pneumoniae inhalatory infection was elaborated. The highly virulent bacterial strain (inhalation LD50 = 400 CFU), applied via the natural route into the respiratory tract elicits an acute infectious process possessing characteristic dynamics. Although the intensity of clearance in the bronchoalveolar lavage after challenge or the mean survival time can be used in individual cases for quantitative resistance determination, the inhalation LD50 values yielded the most standard results. Systemic immunization with the corpuscular K. pneumoniae vaccine provided a high protection expressed by increasing the inhalation LD50 by two orders of magnitude. The antibodies formed, detectable by the ELISA test, are specific for capsular polysaccharide. The type-specific immunity was also found in the protection test. The nonspecific stimulatory effect of the peptidopolysaccharide complex isolated from Listeria monocytogenes (EiF) was manifested at the level of one LD50 only while with higher infectious doses it was absent. However, the adjuvant activity of EiF was significant. The HRA can distinguish and quantitatively determine both nonspecific and specific stimulatory effects of immunomodulatory substances.

Animals↗
PubMed1985

Antibacterial immunity of lower airways: local or localized?

Clearance of bacteria in the bronchoalveolar lavage, the level and functional activity of IgA and changes in the cellular composition of BAL were examined in mice after supralaryngeal immunization and subsequent challenge with Klebsiella pneumoniae. More than 60% of the bacterial inoculum was removed by nonspecific mechanisms within 90 min after inoculation; within the time interval 1.5-3.5 h, clearance was significantly accelerated in locally immunized mice. The enhancement of clearance effectiveness is specific and increases proportionally with the length of immunization (1 less than 2 less than 4 weeks); it is of short duration and towards the end of the 3rd week after immunization, in 73% of immunized animals, the clearance values did not differ from values found in controls. The local immunization did not influence the total level of IgA in BAL, the formation of specific IgA antibody was minimal, in vivo binding of IgA to klebsiella could not be demonstrated. In immunized mice, a significant increase in the numbers of PMN and lymphocytes, as well as an increased activity of phagocytic cell (PMN, MP) was found in BAL. The time interval of 1.5-3.5 h after challenge bounds the space for mechanisms, activated by local immunization in lower airways. The actual participation of individual factors in the accelerated elimination of bacteria from the lumen of airways, remains unclear so far.

Animals↗