The Role of 3D Printing in Planning Complex Medical Procedures and Training of Medical Professionals-Cross-Sectional Multispecialty Review.

Medicine is a rapidly-evolving discipline, with progress picking up pace with each passing decade. This constant evolution results in the introduction of new tools and methods, which in turn occasionally leads to paradigm shifts across the affected medical fields. The following review attempts to showcase how 3D printing has begun to reshape and improve processes across various medical specialties and where it has the potential to make a significant impact. The current state-of-the-art, as well as real-life clinical applications of 3D printing, are reflected in the perspectives of specialists practicing in the selected disciplines, with a focus on pre-procedural planning, simulation (rehearsal) of non-routine procedures, and on medical education and training. A review of the latest multidisciplinary literature on the subject offers a general summary of the advances enabled by 3D printing. Numerous advantages and applications were found, such as gaining better insight into patient-specific anatomy, better pre-operative planning, mock simulated surgeries, simulation-based training and education, development of surgical guides and other tools, patient-specific implants, bioprinted organs or structures, and counseling of patients. It was evident that pre-procedural planning and rehearsing of unusual or difficult procedures and training of medical professionals in these procedures are extremely useful and transformative.

Long-Term Administration of Abacavir and Etravirine Impairs Semen Quality and Alters Redox System and Bone Metabolism in Growing Male Wistar Rats.

Highly active antiretroviral therapy (HAART) is used in HIV-infected patients. Alongside the prolongation of patients' life, adverse side effects associated with long-term therapy are becoming an increasing problem. Therefore, optimizing of HAART is extremely important. The study is aimed at evaluating the toxicity of abacavir and etravirine in monotherapy on the reproductive system, liver, kidneys, and bones in young, sexually mature, male rats. Thirty-six 8-week-old male Wistar rats randomized into three 12-animal groups received either normal saline (control), abacavir 60 mg/kg (AB group), or etravirine 40 mg/kg (ET group) once daily for 16 weeks. Semen morphology, oxide-redox state parameters (MDA, SOD, catalase, GPx, glutathione, GSH/GSSG ratio) in tissue homogenates (testes, liver, kidneys), and serum samples were studied. In bones, microcomputed tomography and a four-point bending test were performed. Total sperm count, sperm concentration, motility, and sperm morphology did not differ significantly in AB or ET groups compared to the control. In the flow cytometry of semen, an increased percentage of cells with denatured DNA was noticed for both tested drugs. However, no significant changes of oxide-redox state in testicular homogenates were found, except of increased SOD activity in the AB-receiving group. Additionally, ET significantly altered catalase and GPx in the liver and SOD activity in kidneys. Abacavir decreased catalase in the liver and GSH levels in kidneys. AB caused significant changes to bone microarchitecture (bone volume fraction, trabecular number, connectivity density, total porosity) and increased Young's modulus. Etravirine had a greater impact on macrometric parameters of bones (tibial index, mid-tibial diameter, femur length). After 4 weeks in the ET group, a lower 1,25-dihydroxyvitamin D3 serum concentration was found. The results showed that abacavir and etravirine disturb oxidative stress. An increase in the percentage of sperms with chromatin damage suggests decreased fertility in rats receiving the studied drugs. Both drugs affected bone formation in growing rats. Additionally, etravirine disturbed vitamin D metabolism.

Intra-arterial transplantation of stem cells in large animals as a minimally-invasive strategy for the treatment of disseminated neurodegeneration.

Stem cell transplantation proved promising in animal models of neurological diseases; however, in conditions with disseminated pathology such as ALS, delivery of cells and their broad distribution is challenging. To address this problem, we explored intra-arterial (IA) delivery route, of stem cells. The goal of this study was to investigate the feasibility and safety of MRI-guided transplantation of glial restricted precursors (GRPs) and mesenchymal stem cells (MSCs) in dogs suffering from ALS-like disease, degenerative myelopathy (DM). Canine GRP transplantation in dogs resulted in rather poor retention in the brain, so MSCs were used in subsequent experiments. To evaluate the safety of MSC intraarterial transplantation, naïve pigs (n = 3) were used as a pre-treatment control before transplantation in dogs. Cells were labeled with iron oxide nanoparticles. For IA transplantation a 1.2-French microcatheter was advanced into the middle cerebral artery under roadmap guidance. Then, the cells were transplanted under real-time MRI with the acquisition of dynamic T2*-weighted images. The procedure in pigs has proven to be safe and histopathology has demonstrated the successful and predictable placement of transplanted porcine MSCs. Transplantation of canine MSCs in DM dogs resulted in their accumulation in the brain. Interventional and follow-up MRI proved the procedure was feasible and safe. Analysis of gene expression after transplantation revealed a reduction of inflammatory factors, which may indicate a promising therapeutic strategy in the treatment of neurodegenerative diseases.

A rare cause of newborn central cyanosis.

Pulmonary arteriovenous malformations are rare congenital vascular anomalies. They are usually associated with congenital hemorrhagic hemangioma. The hemodynamic effect of fistulas depends on their size, as well as the location. The most common manifestations include central cyanosis, ischemic stroke, murmur over the lung fields, cardiomegaly and, less often, heart failure. We present the case of a child who was admitted to the Department of Pediatric Cardiology and Congenital Heart Defects due to central cyanosis and heart murmur.

Age-related differences in function and structure of rat livers subjected to ischemia/reperfusion.

INTRODUCTION: Liver function is affected during ischemia/reperfusion (IR). The current state of knowledge about liver aging processes during IR is incomplete. We evaluated the effects of aging on liver structure and function under IR conditions. MATERIAL AND METHODS: Animals were divided into control (C-2) and ischemia/reperfusion (IR-2) groups of young rats (2-4 months old) and C-12 and IR-12 groups of old rats (12-14 months old). The livers from IR-2 and IR-12 groups were subjected to partial ischemia (60 min), followed by global reperfusion (4 h). Blood samples were obtained during reperfusion (0, 30 and 240 min) to estimate the activity of aminotransferases (ALT, AST). After IR, tumor necrosis factor-α (TNF-α), interleukin-1b (IL-1b), malondialdehyde (MDA), and superoxide dismutase (SOD) were determined in liver homogenates. RESULTS: At all points of reperfusion, an increase in aminotransferase activity levels in the ischemic groups was observed; mainly between IR-12 and C-12 rats. The concentration of TNF-α was significantly higher in young animals (in non-ischemic groups: p = 0.09, in ischemic groups: p = 0.05). Under IR conditions, the concentration of IL-1b dropped (p = 0.05). The concentration of MDA was significantly higher in mature animals (in non-ischemic groups: p = 0.09, in ischemic groups: p = 0.05). In ischemic groups an increase in necrosis rate was observed regardless of age. Rats in the IR-12 group showed the most pronounced changes in hepatic architecture, including increased micro- and macrosteatosis and parenchymal cell destruction. CONCLUSIONS: The function and structure of mature livers slightly deteriorate with age and these differences are more noticeable under IR conditions.

Oral administration of kaempferol inhibits bone loss in rat model of ovariectomy-induced osteopenia.

BACKGROUND: Postmenopausal osteoporosis and osteoporotic fractures constitute an increasing problem in developing countries. Kaempferol, isolated from seeds of Cuscuta chinensis, is an active flavonoid inhibiting in vitro osteoclast activity. The aim of the presented research was an assessment of kaempferol effect on estrogen-deficiency-induced bone structure disturbances in rats. METHODS: The study was performed on 24 Wistar female rats divided into 3 groups: SHAM - rats undergoing a "sham" surgery, OVX-C - control group of animals that underwent ovariectomy, OVX-K - rats undergoing ovariectomy and receiving kaempferol for 8 weeks (from day 56 to day 112). RESULTS: In the OVX-K group, contrary to the OVX-C one, there was no significant decrease in femoral bone mineral density (BMD). A significant increase in Young's modulus was observed in the OVX-K group compared to the OVX-C (15.33±2.51GPa vs. 11.14±1.93GPa, p<0.05). A decreased bone turnover was detected in the OVX-K group. Tissue volume ratio (BV/TV) and trabecular bone perimeter were increased in the OVX-K group compared to the OVX-C one (0.241±0.037 vs. 0.170±0.022, p<0.05 and 15.52±2.78mm vs. 9.67±3.07mm, p<0.05, respectively). CONCLUSION: Kaempferol has a beneficial influence on estrogen-deficiency-induced disturbances of bone structure in rats.

Cardiac tumors in children: A 20-year review of clinical presentation, diagnostics and treatment.

BACKGROUND: The use of new imaging techniques has contributed significantly to earlier diagnosis and treatment of cardiac tumors. OBJECTIVES: The aim of the study was to analyze data from children with cardiac tumors in terms of clinical presentation, the role of noninvasive diagnostic procedures and the long-term outcome. MATERIAL AND METHODS: The data analyzed retrospectively concerned 30 children in whom cardiac tumors were diagnosed from January 1995 to July 2015. The cardiac evaluation included a review of the subjects' medical records and medical history, a physical examination, standard 12-lead electrocardiography, echocardiography and 24-h Holter ECG monitoring at the time of diagnosis and at 6-12 month intervals during the follow-up at the authors' outpatient clinic. RESULTS: Most of the children did not need cardiac surgery; surgical tumor excision was necessary in 3 cases only. There was 1 death in the follow-up period. Rhabdomyoma was diagnosed in 22 cases, and in 16 of them tuberous sclerosis was confirmed during the follow-up period. In the remaining 8 cases, fibroma was the most likely diagnosis. CONCLUSIONS: The symptomatology of cardiac tumors in children can vary greatly, from the absence of any symptoms up to heart failure and respiratory distress indicating the need for surgical intervention. The diagnosis of cardiac tumors relies almost exclusively on noninvasive imaging techniques. The observations in this study confirm the fact that the most common cardiac tumor in children is rhabdomyoma, which may disappear spontaneously. Most patients with cardiac tumors do not require treatment.

Expression of hypoxia inducible factor 1α and antioxidant enzymes: Superoxide dismutases-1 and -2 in ischemic porcine endometrium.

The aim of this study was to determine how 60-min ischemia changes the expression of hypoxia inducible factor 1α (HIF-1α) and superoxide dismutases (SOD)-1 and -2 in selected regions of porcine uterine horns. The results showed that 60-min ischemia of the porcine uterus conducted at the mid-secretory estrous phase caused decreased HIF-1α and increased SOD-2 gene expression. Higher expression of SOD-2 suggests that this enzyme may play an important role in the suppression of HIF-1α accumulation in an ischemic endometrium.

The impact of morin, a natural flavonoid, on cyclophosphamide-induced changes in the oxidative stress parameters in rat livers.

BACKGROUND: Cyclophosphamide (CPX) has many adverse effects, partly due to oxidative stress induction in various tissues. Morin is one of the natural flavonoids with strong antioxidant properties. OBJECTIVES: The aim of the current research was to estimate the influence of morin on changes in antioxidant parameters in rat livers after cyclophosphamide administration. MATERIAL AND METHODS: The study was performed on Wistar rats. The rats in Group C received 0.9% saline; those in Group CX received cyclophosphamide (CPX); and those in Group M-CX received CPX with morin. Cyclophosphamide and morin were given by gastric gavage for 10 consecutive days at doses of 15 mg/kg and 100 mg/kg, respectively. Malondialdehyde (MDA) and glutathione (GSH) concentrations, superoxide dismutase (SOD) activity and catalase (CAT) activity were determined in liver tissue homogenates. RESULTS: CPX caused a significant decrease in SOD activity and GSH levels, but only the latter was fully restored by morin. There were no significant differences in CAT activity in the various groups. CPX also insignificantly decreased MDA levels, which was aggravated by co-administration of morin. CONCLUSIONS: The results obtained indicate that morin may exert some protective action on CPX-induced changes in the antioxidant state in rat livers.

Age-related changes in ADMA-DDAH-NO pathway in rat liver subjected to partial ischemia followed by global reperfusion.

BACKGROUND: Liver function is affected during ischemia/reperfusion (IR). We evaluated the effect of the aging process on selected parameters determining the NO level in rat liver subjected to IR. METHODS: The animals were divided into the C-2 and the IR-2 group of young rats (2-4 months old) and the C-12 and the IR-12 group of older rats (12-14 months old). Livers belonging to the IR-2 and the IR-12 group were subjected to partial ischemia (60 min) and reperfusion (4 h). Blood samples were obtained after surgeries to estimate the activity of aminotransferases, as well as just before ischemia and during reperfusion (15, 120, and 240 min) to estimate concentration of arginine (Arg) and its derivatives: asymmetric and symmetric dimethylarginine (ADMA, SDMA). After IR, dimethylarginine dimethylaminohydrolase (DDAH) activity and protein concentration of inducible nitric oxide synthase (iNOS) were measured in liver homogenates. RESULTS: In the IR-2 group ADMA level increased the most between 15 and 120 min of reperfusion and was the highest of all the groups (0.72±0.2 µmol/l). In the IR-12 group ADMA level decreased significantly and was lower compared to all the other groups at 15 min (0.42±0.2 µmol/l) and to IR-2 at 120 (0.52±0.1 µmol/l) and 240 min (0.38±0.1 µmol/l) of reperfusion. Only the IR-2 group SDMA level increased significantly between 15 (0.75±0.9 µmol/l) and 240 min (1.0±1.2 µmol/l) of reperfusion. At the beginning of the surgery the Arg level was significantly higher in young rats (C-2: 102.1±35.7 µmol/l; IR-2: 114.63±28.9 µmol/l) than in older ones (C-12: 41.88±44.7 µmol/l; IR-12: 28.64±30.6 µmol/l). In the C-2 group the Arg level (77.41±37.5 µmol/l) and Arg/ADMA (A/A) ratio (138.03±62.8 µmol/l) were significantly higher compared to the ischemic groups at 15 min and to all the other groups at 120 (Arg: 47.17±31.7 µmol/l; A/A: 88.28±66.2 µmol/l) and 240 min (Arg: 43.87±21.9 µmol/l; A/A: 118.02±106.3 µmol/l). In the IR-2 group Arg level (11.4±12.0 µmol/l) and A/A ratio (16.11±16.2 µmol/l) decreased significantly at 15 min and during the next phase of reperfusion the levels of those parameters were low, comparably to those in IR-12. As a result of IR, a decrease in DDAH activity and an increase in iNOS protein concentration were observed only in the young rats. CONCLUSIONS: We found that in the non-ischemic groups the Arg level may be affected by the aging process. Under IR conditions, important changes in DDAH-ADMA-NO pathway were observed only in young livers.

Influence of ezetimibe on ADMA-DDAH-NO pathway in rat liver subjected to partial ischemia followed by global reperfusion.

BACKGROUND: We evaluated effect of ezetimibe on selected parameters determining NO level in rat liver subjected to ischemia reperfusion (IR). METHODS: Rats received ezetimibe (5 mg/kg) (groups E0 and EIR) or saline solution (groups C0 and CIR) intragastrically for 21 days. Then, the livers of CIR and EIR underwent ischemia (60 min) and reperfusion (4 h). Blood samples were obtained before surgery to estimate activities of aminotransferases, and just before ischemia and during reperfusion to estimate asymmetric and symmetric dimethylarginine (ADMA, SDMA) and arginine (Arg) levels. After IR, dimethylarginine dimethylaminohydrolase (DDAH) activity and endothelial nitric oxide synthase (eNOS) protein concentration were measured in liver homogenates. DDAH and protein arginine methyltransferase (PRMT) mRNA were quantified by real-time PCR in liver tissue samples. RESULTS: In CIR, the ADMA level was significantly higher compared to all other groups in 30 min and to E0 group in 120 min of reperfusion. In EIR, ADMA was low, compared to non-ischemic groups. At 30 and 120 min of reperfusion, in non-ischemic groups the level of Arg and Arg/ADMA ratio were significantly higher than in ischemic groups and E0 was the group with the highest levels of those parameters of all. In CIR, eNOS protein concentration was significantly lower than in ezetimibe-treated groups. Activity of DDAH was significantly higher in E0 than in non-treated groups. In ischemic groups, DDAH mRNA expression was significantly higher than in non-ischemic ones and PRMT mRNA expression was significantly higher in C0 than in all other groups. CONCLUSIONS: Influence of ezetimibe on ADMA/DDAH/NO pathway demonstrated in this work may suggest protective properties of this drug on rat livers injured by IR and, to a lower extent, on livers non-subjected to IR.

Complementation studies of the DnaK-DnaJ-GrpE chaperone machineries from Vibrio harveyi and Escherichia coli, both in vivo and in vitro.

The marine bacterium Vibrio harveyi is a potential indicator organism for evaluating marine environmental pollution. The DnaK-DnaJ-GrpE chaperone machinery of V. harveyi has been studied as a model of response to stress conditions and compared to the Escherichia coli DnaK system. The genes encoding DnaK, DnaJ and GrpE of V. harveyi were cloned into expression vectors and grpE was sequenced. It was found that V. harveyi possesses a unique organization of the hsp gene cluster (grpE-gltP-dnaK-dnaJ), which is present exclusively in marine Vibrio species. In vivo experiments showed that suppression of the E. coli dnaK mutation by V. harveyi DnaK protein was weak or absent, while suppression of the dnaJ and grpE mutations by V. harveyi DnaJ and GrpE proteins was efficient. These results suggest higher species-specificity of the DnaK chaperone than the GrpE and DnaJ cochaperones. Proteins of the DnaK chaperone machinery of V. harveyi were purified to homogeneity and their efficient cooperation with the E. coli chaperones in the luciferase refolding reaction and in stimulation of DnaK ATPase activity was demonstrated. Compared to the E. coli system, the purified DnaK-DnaJ-GrpE system of V. harveyi exhibited about 20% lower chaperoning activity in the luciferase reactivation assay. ATPase activity of V. harveyi DnaK protein was at least twofold higher than that of the E. coli model DnaK but its stimulation by the cochaperones DnaJ and GrpE was significantly (10 times) weaker. These results indicate that, despite their high structural identity (approximately 80%) and similar mechanisms of action, the DnaK chaperones of closely related V. harveyi and E.coli bacteria differ functionally.