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1.
World J Methodol ; 14(2): 92982, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38983668

ABSTRACT

In accordance with the World Health Organization data, cancer remains at the forefront of fatal diseases. An upward trend in cancer incidence and mortality has been observed globally, emphasizing that efforts in developing detection and treatment methods should continue. The diagnostic path typically begins with learning the medical history of a patient; this is followed by basic blood tests and imaging tests to indicate where cancer may be located to schedule a needle biopsy. Prompt initiation of diagnosis is crucial since delayed cancer detection entails higher costs of treatment and hospitalization. Thus, there is a need for novel cancer detection methods such as liquid biopsy, elastography, synthetic biosensors, fluorescence imaging, and reflectance confocal microscopy. Conventional therapeutic methods, although still common in clinical practice, pose many limitations and are unsatisfactory. Nowadays, there is a dynamic advancement of clinical research and the development of more precise and effective methods such as oncolytic virotherapy, exosome-based therapy, nanotechnology, dendritic cells, chimeric antigen receptors, immune checkpoint inhibitors, natural product-based therapy, tumor-treating fields, and photodynamic therapy. The present paper compares available data on conventional and modern methods of cancer detection and therapy to facilitate an understanding of this rapidly advancing field and its future directions. As evidenced, modern methods are not without drawbacks; there is still a need to develop new detection strategies and therapeutic approaches to improve sensitivity, specificity, safety, and efficacy. Nevertheless, an appropriate route has been taken, as confirmed by the approval of some modern methods by the Food and Drug Administration.

2.
Gels ; 10(5)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38786212

ABSTRACT

Biomedicine is constantly evolving to ensure a significant and positive impact on healthcare, which has resulted in innovative and distinct requisites such as hydrogels. Chitosan-based formulations stand out for their versatile utilization in drug encapsulation, transport, and controlled release, which is complemented by their biocompatibility, biodegradability, and non-immunogenic nature. Stimuli-responsive hydrogels, also known as smart hydrogels, have strictly regulated release patterns since they respond and adapt based on various external stimuli. Moreover, they can imitate the intrinsic tissues' mechanical, biological, and physicochemical properties. These characteristics allow stimuli-responsive hydrogels to provide cutting-edge, effective, and safe treatment. Constant progress in the field necessitates an up-to-date summary of current trends and breakthroughs in the biomedical application of stimuli-responsive chitosan-based hydrogels, which was the aim of this review. General data about hydrogels sensitive to ions, pH, redox potential, light, electric field, temperature, and magnetic field are recapitulated. Additionally, formulations responsive to multiple stimuli are mentioned. Focusing on chitosan-based smart hydrogels, their multifaceted utilization was thoroughly described. The vast application spectrum encompasses neurological disorders, tumors, wound healing, and dermal infections. Available data on smart chitosan hydrogels strongly support the idea that current approaches and developing novel solutions are worth improving. The present paper constitutes a valuable resource for researchers and practitioners in the currently evolving field.

3.
World J Clin Oncol ; 15(4): 523-530, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38689621

ABSTRACT

Britanin is a bioactive sesquiterpene lactone known for its potent anti-inflammatory and anti-oxidant properties. It also exhibits significant anti-tumor activity, suppressing tumor growth in vitro and in vivo. The current body of research on Britanin includes thirty papers predominantly related to neoplasms, the majority of which are gastrointestinal tumors that have not been summarized before. To drive academic debate, the present paper reviews the available research on Britanin in gastrointestinal tumors. It also outlines novel research directions using data not directly concerned with the digestive system, but which could be adopted in future gastrointestinal research. Britanin was found to counteract liver, colorectal, pancreatic, and gastric tumors, by regulating proliferation, apoptosis, autophagy, immune response, migration, and angiogenesis. As confirmed in pancreatic, gastric, and liver cancer, its most commonly noted molecular effects include nuclear factor kappa B and B-cell lymphoma 2 downregulation, as well as Bcl-2-associated X protein upregulation. Moreover, it has been found to induce the Akt kinase and Forkhead box O1 axis, activate the AMP-activated protein kinase pathway, elevate interleukin-2 and peroxisome proliferator-activated receptor-γ levels, reduce interleukin-10, as well as downregulate matrix metalloproteinase-9, Twist family bHLH transcription factor 1, and cyclooxygenase-2. It also inhibits Myc-HIF1α interaction and programmed death ligand 1 transcription by interrupting the Ras/ RAF/MEK/ERK pathway and mTOR/P70S6K/4EBP1 signaling. Future research should aim to unravel the link between Britanin and acetylcholinesterase, mast cells, osteolysis, and ischemia, as compelling data have been provided by studies outside the gastrointestinal context. Since the cytotoxicity of Britanin on noncancerous cells is significantly lower than that on tumor cells, while still being effective against the latter, further in-depth studies with the use of animal models are merited. The compound exhibits pleiotropic biological activity and offers considerable promise as an anti-cancer agent, which may address the current paucity of treatment options and high mortality rate among patients with gastrointestinal tumors.

4.
Article in English | MEDLINE | ID: mdl-38797909

ABSTRACT

Hemophilia is a plasma bleeding disorder characterized by a deficiency of certain blood clotting factors. The most common forms of this disease, i.e., type A and type B, affect approximately 400,000 people worldwide. Without appropriate treatment ensuring the proper coagulation cascade, this disease may lead to serious disability. Minimizing patient discomfort is possible via replacement therapy, consisting of the substitution of a missing coagulation factor via intravenous administration. Frequent medication and the risk related to factor inhibitors are significant disadvantages, necessitating the improvement of current therapies or the development of novel ones. This review examines the humanized bispecific antibody Emicizumab which ensures hemostasis by mimicking the action of the coagulation factor VIII, a deficiency of which causes type A hemophilia. The paper outlines the topic and then summarizes available clinical trials on Emicizumab in type A hemophilia. Several interventional clinical trials have found Emicizumab to be effective in decreasing bleeding episodes and raising patient satisfaction among various hemophilia A populations. Current Emicizumab-related trials are forecast to be completed between 2024 and 2030, and in addition to congenital hemophilia A, the trials cover acquired hemophilia A and patients playing sports. Providing a more comprehensive understanding of Emicizumab may revolutionize the management of hemophilia type A and improve quality of life. Conclusively, Emicizumab is a gentler therapy owing to subcutaneous delivery and fewer injections, which reduces injection-site reactions and makes therapy less burdensome, ultimately decreasing hospital visits and indirect costs.

5.
J Clin Med ; 13(6)2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38541840

ABSTRACT

Background: The complications associated with Meckel's diverticulum (MD) are well-known. However, blunt injuries regarding MD have not been widely described in the literature. This was the reason for undertaking research on MD lesions. Materials and Methods: The materials consisted of 28 cases of damage to MD after blunt trauma published during the years 1921-2022. The collected data were subjected to statistical analysis. Results: The following MD injuries have been identified, starting with the most common isolated perforation of MD, bleeding from the area of MD, perforation of MD with concomitant tearing of the mesentery intestines and bleeding, intussusception of MD, and intramural hematoma of MD with adjacent mesenteric hematoma. Most injuries were caused by a traffic accident, followed by sports, accidents at work, and then violence. Almost all the cases (27) involved men. Several possible mechanisms may contribute to post-traumatic damage to MD. First of all, they are associated with abdominal compression and a secondary increase in intra-abdominal pressure as well as with the action of shearing forces during deceleration. Conclusions: Traumatic MD injuries are differentiated and very rare. They can coexist with other serious injuries to the abdominal organs.

6.
Biomol Concepts ; 15(1)2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38530804

ABSTRACT

Among civilization diseases, the number of individuals suffering from type 2 diabetes (T2DM) is expected to increase to more than a billion in less than 20 years, which is associated with, e.g., populational aging, poor diet, sedentary lifestyle, genetic predispositions, and immunological factors. T2DM affects many organs and is characterized by insulin resistance, high glucose levels, and adipocyte dysfunction, which are related to senescence. Although this type of cellular aging has beneficial biological functions, it can also act unfavorable since senescent adipocytes resist apoptosis, enhance cytokine secretion, downregulate cell identity genes, and acquire the senescence-associated secretory phenotype that renders a more oxidative environment. Opposing T2DM is possible via a wide variety of senotherapies, including senolytics and senomorphics; nevertheless, further research is advised to expand therapeutic possibilities and benefits. Consequences that ought to be deeply researched include secretory phenotype, chronic inflammation, increasing insulin resistance, as well as impairment of adipogenesis and functioning of adipocyte cells. Herein, despite reviewing T2DM and fat tissue senescence, we summarized the latest adipocyte-related anti-diabetes solutions and suggested further research directions.


Subject(s)
Diabetes Mellitus, Type 2 , Insulin Resistance , Humans , Insulin Resistance/genetics , Adipocytes , Cellular Senescence/genetics , Aging
7.
J Funct Biomater ; 14(9)2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37754888

ABSTRACT

Hydrogels have various applications in medicine, for example, in systems for controlled drug release or as wound dressings, where they provide an appropriate environment for healing and constitute a barrier to microorganisms. The aim of this study was to evaluate the action of carboxymethyl chitosan (CMCS) hydrogels in wound healing therapy in vivo using a laboratory rat model. The hydrogels were formed from aqueous solutions of a CMCS biopolymer via electron beam irradiation, with the presence of a crosslinking agent of poly(ethylene glycol) diacrylate. A histopathological examination of injured tissue, using a model of a hard-to-heal wound, indicated that the CMCS hydrogel supported healing. The new gel dressing, being noncytotoxic, presents great potential in wound treatment, with positive effects on the amount of inflammatory infiltration, young collagen formation, and the degree of epidermalization. A key advantage of the current approach (i.e., using competitive radiation technology for synthesis) is that it includes only one step, with the product being sterilized as it is synthesized. The hydrogel effectively supports wound healing and can serve as a bio-based and biodegradable platform for other medical applications.

8.
J Mol Med (Berl) ; 101(8): 961-972, 2023 08.
Article in English | MEDLINE | ID: mdl-37460699

ABSTRACT

The diminishing supply and increasing costs of donated blood have motivated research into novel hemoglobin-based oxygen carriers (HBOCs) that can serve as red blood cell (RBC) substitutes. HBOCs are versatile agents that can be used in the treatment of hemorrhagic shock. However, many of the RBC substitutes that are based on mammalian hemoglobins have presented key limitations such as instability and toxicity. In contrast, erythrocruorins (Ecs) are other types of HBOCs that may not suffer these disadvantages. Ecs are giant metalloproteins found in annelids, crustaceans, and some other invertebrates. Thus far, the Ecs of Lumbricus terrestris (LtEc) and Arenicola marina (AmEc) are the most thoroughly studied. Based on data from preclinical transfusion studies, it was found that these compounds not only efficiently transport oxygen and have anti-inflammatory properties, but also can be modified to further increase their effectiveness. This literature review focuses on the structure, properties, and application of Ecs, as well as their advantages over other HBOCs. Development of methods for both the stabilization and purification of erythrocruorin could confer to enhanced access to artificial blood resources.


Subject(s)
Blood Substitutes , Erythrocruorins , Animals , Oxygen/metabolism , Hemoglobins , Blood Substitutes/chemistry , Mammals/metabolism
9.
Polymers (Basel) ; 15(1)2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36616494

ABSTRACT

Hydrogels have the properties of solid substances and are useful for medicine, e.g., in systems for the controlled release of drugs or as wound dressings. They isolate the wound from the external environment and constitute a barrier to microorganisms while still being permeable to oxygen. In the current study, hydrogels were formed from concentrated aqueous solutions of carboxymethyl chitosan (CMCS) via electron beam irradiation, with the presence of a crosslinking agent: poly(ethylene glycol)diacrylate. The aim of the study was to compare the properties and action of biopolymer CMCS hydrogels with commercial ones and to select the best compositions for future research towards wound-dressing applications. The elasticity of the gel depended on the component concentrations and the irradiation dose employed to form the hydrogel. Young's modulus for the tested hydrogels was higher than for the control material. The Live/Dead test performed on human fibroblasts confirmed that the analyzed hydrogels are not cytotoxic, and for some concentrations, they cause a slight increase in the number of cells compared to the control. The biocompatibility studies carried out on laboratory rats showed no adverse effect of hydrogels on animal tissues, confirming their biocompatibility and suggesting that CMCS hydrogels could be considered as wound-healing dressings in the future. Ionizing radiation was proven to be a suitable tool for CMCS hydrogel synthesis and could be of use in wound-healing therapy, as it may simultaneously sterilize the product.

10.
Hum Cell ; 33(3): 859-867, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32449113

ABSTRACT

A new series of tetrahydroacridine derivatives with the fluorobenzoyl moiety was synthesized and evaluated for cytotoxic activity against lung cancer cell lines A549 and colorectal cancer HT29. The cytotoxic activity of the compounds was compared on the somatic cell line-EAhy926. Compounds showed high cytotoxic activity on A549 cells (IC50 183.26-68.07 µM) and HT29 cells (IC50 68.41-19.70 µM), higher than controls-etoposide (IC50 451.47 µM) toward A549 and 5-fluorouracil (IC50 1626.85 µM) against HT29. Derivative 4 was the most cytotoxic to A549, whereas for the cell lines HT29 compound 6. Selected compounds showed similar cytotoxicity to the EAhy926 cell line (IC50 about 50 µM). In the hyaluronidase inhibition assay, all compounds exhibited anti-inflammatory activity, including 4 exhibiting the best inhibitory activity-IC50 of 52.27 µM when the IC50 heparin was 56.41 µM. Mathematical modeling was performed to determine LD50 after intraperitoneal, oral, intravenous and subcutaneous administration and to predict potential mutagenicity and carcinogenicity of the compounds analyzed. Obtained results showed that tested derivatives are slightly toxic compounds, and LD50 values (mg/kg) ranged from 680 to 1200 (oral rat model), the analyzed compounds have low mutagenic potential, and differences between derivatives are insignificant and very low probability of carcinogenicity. To confirm mathematical calculations, an in vivo test was carried out on a laboratory mouse model for two selected compounds. It allowed to qualify compounds: 6 to category 4 of the GHS scale, and 4 to category 3 of the GHS scale.


Subject(s)
Acridines/toxicity , Colorectal Neoplasms/pathology , Lung Neoplasms/pathology , Acridines/administration & dosage , Acridines/chemical synthesis , Acridines/chemistry , Animals , Cell Line, Tumor , Disease Models, Animal , Fluorobenzenes , Humans , Hyaluronoglucosaminidase/antagonists & inhibitors , Lethal Dose 50 , Mice , Rats , Toxicity Tests/methods
11.
Pol Przegl Chir ; 93(1): 9-14, 2020 Oct 05.
Article in English | MEDLINE | ID: mdl-33729171

ABSTRACT

<b>Introduction:</b> The perforation of gloves during surgical procedures is quite common. A cheap and quite effective method of reducing the risk of blood-borne infections is wearing two pairs of gloves. Unfortunately, some surgeons are reluctant to it, and they report decreased dexterity and sensation. The aim of the study was to evaluate surgeons' double-gloving practices to determine the factors related to compliance. <br><b>Material and methods:</b> An anonymous, 21-question survey in Polish was sent by post to 41 surgical departments. The questions concerned: demographic data, type of surgical gloves used, allergy to latex, number of surgeries performed, frequency of using double gloves and negative impressions from using them and finally, the frequency of needlestick injuries during surgical procedures. <br><b>Results:</b> We received 179 questionnaires back. More than 62% of the surgeons believe that double gloves provide better protection than a single pair, 24% do not believe in this, and 14% have no opinion. Only 0.6% of respondents always use double gloves during surgery, 19% double glove in at least 25% of cases and 68% do it occasionally. 13% of the surgeons declared that they had never worn double gloves. During high-risk procedures, 86% of respondents wear double gloves. About half of respondents (50.3%) report discomfort while wearing double gloves; 45% - decreased dexterity; about 30% complain of numbness and tingling; and 64% - decreased sensation. <br><b>Conclusion:</b> Due to the high number of surgical glove perforations and relatively high prevalence of needlestick injuries, it is necessary to use methods that reduce the risk of transmission of pathogens. The habit of using a double pair of gloves should be implemented especially among young surgeons starting to train in their specialities. Consequently, the period of initial discomfort will be combined with the acquisition of surgical skills, which will allow for gradual acclimatization.


Subject(s)
Equipment Failure/statistics & numerical data , Gloves, Surgical/adverse effects , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Infectious Disease Transmission, Professional-to-Patient/prevention & control , Needlestick Injuries/prevention & control , Postoperative Complications/prevention & control , Attitude of Health Personnel , Clinical Competence , Gloves, Surgical/statistics & numerical data , Hand Injuries/prevention & control , Humans , Needlestick Injuries/epidemiology , Occupational Diseases/prevention & control
12.
Mol Cell Biochem ; 460(1-2): 123-150, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31313023

ABSTRACT

A series of nine tetrahydroacridine derivatives with iodobenzoic moiety were synthesized and evaluated for their cytotoxic activity against cancer cell lines-A549 (human lung adenocarcinoma), HT-29 (human colorectal adenocarcinoma) and somatic cell line-EA.hy926 (human umbilical vein cell line). All compounds displayed high cytotoxicity activity against A549 (IC50 59.12-14.87 µM) and HT-29 (IC50 17.32-5.90 µM) cell lines, higher than control agents-etoposide and 5-fluorouracil. Structure-activity relationship showed that the position of iodine in the substituent in the para position and longer linker most strongly enhanced the cytotoxic effect. Among derivatives, 1i turned out to be the most cytotoxic and displayed IC50 values of 14.87 µM against A549 and 5.90 µM against HT-29 cell lines. In hyaluronidase inhibition assay, all compounds presented anti-inflammatory activity, however, slightly lower than reference compound. ADMET prediction showed that almost all compounds had good pharmacokinetic profiles. 1b, 1c and 1f compounds turned out to act against chemoresistance in cisplatin-resistant 253J B-V cells. Compounds intercalated into DNA and inhibited cell cycle in G0/G1 phase-the strongest inhibition was observed for 1i in A549 and 1c in HT-29. Among compounds, the highest apoptotic effect in both cell lines was observed after treatment with 1i. Compounds caused DNA damage and H2AX phosphorylation, which was detected in A549 and HT-29 cells. All research confirmed anticancer properties of novel tetrahydroacridine derivatives and explained a few pathways of their mechanism of cytotoxic action.


Subject(s)
Aminacrine/pharmacology , Apoptosis/drug effects , Carcinoma, Non-Small-Cell Lung/pathology , Colorectal Neoplasms/pathology , G1 Phase Cell Cycle Checkpoints/drug effects , Iodobenzoates/pharmacology , Lung Neoplasms/pathology , A549 Cells , Aminacrine/chemistry , Cell Survival/drug effects , Cisplatin/pharmacology , Cytoprotection/drug effects , DNA/metabolism , Drug Resistance, Neoplasm/drug effects , HT29 Cells , Histones/metabolism , Humans , Hyaluronoglucosaminidase/metabolism , Inhibitory Concentration 50 , Mutagens/toxicity , Oxidative Stress/drug effects , Poly(ADP-ribose) Polymerases/metabolism , Tumor Stem Cell Assay
13.
Pol Przegl Chir ; 91(2): 7-11, 2019 Feb 07.
Article in English | MEDLINE | ID: mdl-31032804

ABSTRACT

The aim of this study was to assess whether modified bacterial cellulose can be used for an artificial auricle skeleton. INTRODUCTION: The auricle is a part of the external ear. It consists of skin, cartilage, muscles and adipose tissue. The cartilage gives shape to the structure. There are several indications for reconstruction, such as congenital anomalies, mechanical injuries, and burns, and a range of methods have been proposed for the complete reconstruction of the auricle. MATERIAL AND METHODS: A bacterial cellulose membrane, at least 25 mm in thickness, was produced in vitro by Acetobacter xylinum culture. The entire artificial human auricle skeleton was made to scale to allow its implantation into an animal model - Wistar rats. Forty rats were divided into four groups of 10 animals. Each group was assigned a different resection time: 14 days, 30 days, 90 days or 720 days. After each resection, an examination of the artificial skeleton and the tissues surrounding it was conducted. The surgical procedure was based on the Nagata technique. RESULTS: Resection after 14, 30, 90 and 720 days shows the progression of the healing process and integration of the artificial skeleton into the animal body. There are no signs of change in the shape or structure of the skeleton. DISCUSSION: Several surgical techniques and biotechnological methods have been developed over the past few years to improve the results of facial reconstruction. Other approaches can be used to create auricle cartilage, based on scaffolds and chondrocytes. CONCLUSION: My findings indicate that modified bacterial cellulose can be used to form an effective artificial auricle which appears to maintain its shape and elasticity, with no signs of degradation.


Subject(s)
Bacteria , Cellulose , Ear Auricle/anatomy & histology , Ear Auricle/surgery , Models, Anatomic , Prosthesis Design/methods , Tissue Engineering/methods , Animals , Disease Models, Animal , Humans , Rats , Rats, Wistar
14.
Z Gastroenterol ; 55(10): 1004-1008, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29020699

ABSTRACT

Introduction Colonoscopy trainers have gained recognition for improving endoscopy skills and preparing for real procedures on humans. Unfortunately, due to their high price, commercial simulators are hard to obtain, especially for small medical centers. However, a solution might be to construct a device for themselves. Aim Our goal was to build a relatively cheap and easy-to-construct simulator for residents who want to start learning colonoscopy. Materials and methods The box model colonoscopy trainer was designed and constructed. The artificial colon was made from 2 layers of fabric and rubber rings between them. Velcro attached to the artificial colon and to the box, and the tarp straps that simulate peritoneal adhesions allow the bowel to be arranged in many different configurations. Moreover, some aspects of polypectomy training have been incorporated in the colonoscopy simulator. Results The self-constructed simulator was found to be an effective training device, with the total cost of parts not exceeding $30. Conclusions In this paper, we present the first homemade simulator for colonoscopy training. It offers the opportunity for skills acquisition in a preclinical setting.


Subject(s)
Colonoscopy , Simulation Training , Clinical Competence , Colonoscopy/education , Education, Medical, Graduate , Humans , Simulation Training/methods
15.
Pol Przegl Chir ; 87(2): 65-70, 2015 Feb.
Article in English | MEDLINE | ID: mdl-26146097

ABSTRACT

UNLABELLED: Accurate diagnosis of acute appendicitis (AA) is still a problem and is not always easy, even for experienced surgeons. Studies have shown that 20 to 30% of the appendices removedwere normal. Therefore, various scoring systems have been developed to aid in the diagnosis of doubtful cases and reduce the number of unnecessary appendectomies. The aim of this study was to assess the diagnostic value of different scoring systems in acute appendicitis. MATERIAL AND METHODS: The study involved 94 patients who underwent laparotomy due to suspected acute appendicitis. Medical examination at hospital admission was performed by a resident and a general surgery specialist. The probability of AA was evaluated using six different scoring systems: Alvarado, Fenyo, Eskelinen, Ohman, Tzankis, and RIPASA. The resident calculated the results in individual systems. The decision to perform the operation was taken by a specialist surgeon who did not know the results. RESULTS: Normal appendix was removed in 26% of cases. Eskelinen, RIPASA and Alvarado systems showed highest sensitivity (99%, 88% and 85%, respectively). Tzankis and Fenyo systems showed highest specificity (62% and 50%, respectively). CONCLUSIONS: Our study has shown limited value of scoring systems for the diagnosis of acute appendicitis. The systems may improve diagnostic accuracy as they require obtaining a more detailed medical history, and making a more thorough and organized data analysis. However, the scoring systems should be treated only as an aid to diagnosis.


Subject(s)
Appendectomy , Appendicitis/classification , Appendicitis/diagnosis , Severity of Illness Index , Acute Disease , Appendicitis/epidemiology , Appendicitis/surgery , Databases, Factual , Female , Humans , Male
16.
Wideochir Inne Tech Maloinwazyjne ; 10(1): 87-91, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25960798

ABSTRACT

INTRODUCTION: During laparoscopy, the monitor is usually placed near the operating table, at eye level, which significantly affects hand-eye coordination. First, it is impossible for the surgeon to simultaneously observe the operative field and hand movement. Second, the axis of view of the endoscope rarely matches the natural axis of the surgeon's sight: it resembles a direct view into the operative field. Finally, as the arms of the tools act as levers with a fulcrum at the site of the skin incision, the action of the tool handles is a mirror image of the movement of the tool tips seen on the monitor. Studies have shown that a neutral position with the head flexed at 15-45° is the most ergonomically suitable. AIM: To evaluate whether the level of monitor placement exerts an influence on laparoscopic performance. MATERIAL AND METHODS: A group of 52 students of medicine were asked to pass a thread through 9 holes of different sizes, placed at different levels and angles, using a self-made laparoscopic simulator. Each student performed the task four times in two monitor positions: at eye level, and placed on a simulator. The order of monitor placement was randomized. RESULTS: The task was performed more quickly when the monitor was placed on the simulator and the sight was forced downwards. Lower placement was also found to be more beneficial for students with experience in laparoscopy. CONCLUSIONS: New technologies which place the display on the patient, thus improving the ergonomics of the operation, should be developed.

17.
Arch Med Sci ; 11(1): 210-9, 2015 Mar 16.
Article in English | MEDLINE | ID: mdl-25861309

ABSTRACT

INTRODUCTION: Peripheral nerve disruptions, frequently occurring during limb injuries, give rise to serious complications of patients recovery resulting from limitations in neural tissue regeneration capabilities. To overcome this problem bridging techniques utilizing guidance channels gain their importance. Biodegradable polymeric tubes seem to be more prospective then non-degradable materials - no necessity of implant removal and possibilities of release of incorporated drugs or biologically active agents that may support nerve regeneration process are the main advantages. MATERIAL AND METHODS: Polymer blend of commercial poly(L-lactic acid) (PLLA) and in-house synthesized poly(trimethylene carbonate) (PTMC) were processed in an organic solvent - phase inversion process on a supporting rod - to form a guidance porous tube of 1.1 mm inner diameter. In vivo experiments on rat's cut femoral nerve by using either the tubes or end-to-end suturing (control group) involved 22 and 19 rats, respectively. Motor recovery of operated limbs, neuroma occurrence and histopathology of explanted nerves were evaluated after 30, 60 and 90 days of implantation. RESULTS: Motor recovery of the limbs was of similar rate for the two animal groups. The neuroma formation was evident in over 90% control specimens, while for the bridging group it was less than 40% of all evaluable samples (p = 0.0022). Biocompatibility of applied materials was affirmed by moderate tissue response. CONCLUSIONS: Application of the biodegradable PLLA/PTMC polymeric tubes effectively supports regeneration of discontinued nerves. The applied material prevents neuroma formation, by reducing the scar tissue formation time and, thus, accelerating the process of neural tissue restoration.

18.
Wideochir Inne Tech Maloinwazyjne ; 9(3): 380-6, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25337161

ABSTRACT

INTRODUCTION: Laparoscopic trainers have gained recognition for improving laparoscopic surgery skills and preparing for operations on humans. Unfortunately, due to their high price, commercial simulators are hard to obtain, especially for young surgeons in small medical centers. The solution might be for them to construct a device by themselves. AIM: To make a relatively cheap and easy to construct laparoscopic trainer for residents who wish to develop their skills at home. MATERIAL AND METHODS: TWO LAPAROSCOPIC SIMULATORS WERE DESIGNED AND CONSTRUCTED: 1) a box model with an optical system based on two parallel mirrors, 2) a box model with an HD webcam, a light source consisting of LED diodes placed on a camera casing, and a modeling servo between the webcam and aluminum pipe to allow electronic adjustment of the optical axis. RESULTS: The two self-constructed simulators were found to be effective training devices, the total cost of parts for each not exceeding $100. Advice is also given for future constructors. CONCLUSIONS: Home made trainers are accessible to any personal budget and can be constructed with a minimum of practical skill. They allow more frequent practice at home, outside the venue and hours of surgical departments. What is more, home made trainers have been shown to be comparable to commercial trainers in facilitating the acquisition of basic laparoscopic skills.

20.
Arch Med Sci ; 9(3): 527-34, 2013 Jun 20.
Article in English | MEDLINE | ID: mdl-23847677

ABSTRACT

INTRODUCTION: The subject of the experiment was bacterial nanocellulose, a natural polymer produced by bacteria - Gluconacetobacter xylinus. Following a specific modification process a cartilage-like material for restoration of damaged tissues may be produced. The obtained implants with excellent biocompatibility, mouldability, biophysical and chemical properties perfectly fit the needs of reconstructive surgery. The goal of the experiment was to develop and analyze cellulosic guidance channels in vivo for the reconstruction of damaged peripheral nerves. MATERIAL AND METHODS: The experiments were conducted on Wistar rats, femoral nerve. Cellulose was produced according to a self-patented method. In the experimental group tubulization was applied, whereas in the control traditional end-to-end connection was used. Observation time was 30, 60, 90, and 180 days. Results evaluation included histological analysis and postoperative observation of motor recovery. RESULTS: The overgrowth of connective tissue and disorganisation of neural structures was evident in 86.67% of control specimens, while for cellulosic group it was only 35% (p = 0.0022). Tubulization prevented the excessive proliferation of connective tissue and isolated from penetration with scar tissue. Autocannibalism, being probably an evidence of neurotrophic factors amassment, was observed in cellulosic group but not in the control one. Motor recovery did not differ significantly (p > 0.05). Biocompatibility of implants was affirmed by very small level of tissue response and susceptibility to vascularisation. CONCLUSIONS: Cellulosic neurotubes effectively prevent the formation of neuromas. They are of very good biocompatibility and allow the accumulation of neurotrophic factors inside, thus facilitating the process of nerve regeneration.

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