Ultrastructural features mirror metabolic derangement in human endothelial cells exposed to high glucose

High glucose-induced endothelial dysfunction is the early event that initiates diabetes-induced vascular disease. Here we employed Cryo Soft X-ray Tomography to obtain three-dimensional maps of high D-glucose-treated endothelial cells and their controls at nanometric spatial resolution. We then correlated ultrastructural differences with metabolic rewiring. While the total mitochondrial mass does not change, high D-glucose promotes mitochondrial fragmentation, as confirmed by the modulation of fission-fusion markers, and dysfunction, as demonstrated by the drop of membrane potential, the decreased oxygen consumption and the increased production of reactive oxygen species. The 3D ultrastructural analysis also indicates the accumulation of lipid droplets in cells cultured in high D-glucose. Indeed, because of the decrease of fatty acid β-oxidation induced by high D-glucose concentration, triglycerides are esterified into fatty acids and then stored into lipid droplets. We propose that the increase of lipid droplets represents an adaptive mechanism to cope with the overload of glucose and associated oxidative stress and metabolic dysregulation.

The Interplay between TRPM7 and MagT1 in Maintaining Endothelial Magnesium Homeostasis

The transient receptor potential cation channel subfamily M member 7 (TRPM7) is an ubiquitous channel fused to an α-kinase domain involved in magnesium (Mg) transport, and its level of expression has been proposed as a marker of endothelial function. To broaden our present knowledge about the role of TRPM7 in endothelial cells, we generated stable transfected Human Endothelial Cells derived from the Umbilical Vein (HUVEC). TRPM7-silencing HUVEC maintain the actin fibers' organization and mitochondrial network. They produce reduced amounts of reactive oxygen species and grow faster than controls. Intracellular Mg concentration does not change in TRPM7-silencing or -expressing HUVEC, while some differences emerged when we analyzed intracellular Mg distribution. While the levels of the plasma membrane Mg transporter Solute Carrier family 41 member 1 (SLC41A1) and the mitochondrial channel Mrs2 remain unchanged, the highly selective Magnesium Transporter 1 (MagT1) is upregulated in TRPM7-silencing HUVEC through transcriptional regulation. We propose that the increased amounts of MagT1 grant the maintenance of intracellular Mg concentrations when TRPM7 is not expressed in endothelial cells.

Cluster-Assembled Zirconia Substrates Accelerate the Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells

Due to their high mechanical strength and good biocompatibility, nanostructured zirconia surfaces (ns-ZrOx) are widely used for bio-applications. Through supersonic cluster beam deposition, we produced ZrOx films with controllable roughness at the nanoscale, mimicking the morphological and topographical properties of the extracellular matrix. We show that a 20 nm ns-ZrOx surface accelerates the osteogenic differentiation of human bone marrow-derived MSCs (bMSCs) by increasing the deposition of calcium in the extracellular matrix and upregulating some osteogenic differentiation markers. bMSCs seeded on 20 nm ns-ZrOx show randomly oriented actin fibers, changes in nuclear morphology, and a reduction in mitochondrial transmembrane potential when compared to the cells cultured on flat zirconia (flat-ZrO₂) substrates and glass coverslips used as controls. Additionally, an increase in ROS, known to promote osteogenesis, was detected after 24 h of culture on 20 nm ns-ZrOx. All the modifications induced by the ns-ZrOx surface are rescued after the first hours of culture. We propose that ns-ZrOx-induced cytoskeletal remodeling transmits signals generated by the extracellular environment to the nucleus, with the consequent modulation of the expression of genes controlling cell fate.

Kinetics of moisture loss applied to the baking of snacks with pregelatinized cassava starch

Moisture loss kinetics is a complex process defined as the liquid removal from a solid by thermal application. The purposes of the study were to obtain kinetic curves of moisture loss during the baking of cassava snacks and establish which processes govern the moisture loss, recognize which mathematical models describe the moisture loss curves more precisely, and determine activation energy (Ea) and effective diffusivity (D_eff ). Experimental data were obtained through baking at four temperatures formulations for snacks with different dehydrated cassava puree (DCP) proportions. Page's and Chávez Méndez's models showed the best fits. We calculated D_eff and Ea employing the analytical solution of Fick's Second Law for the geometry of plane plates. D_eff values increase with DCP but did not show a trend. The range found was from 5.22E-06 to 2.93E-05 m² /s. The results of Ea showed that the mixture of flours produced an increase in the energy necessary to initiate the effective diffusion (24.84 kJ/mol) compared to the samples without mixing (15.54 kJ/mol). Moisture loss curves show that the diffusion process governs a large part of the process. PRACTICAL APPLICATION: Given the need to increase research for the development of the cassava industry, which currently has low competitiveness compared to less expensive products such as corn, various efforts are being made to generate new products that can replace wheat flour, at least in part. However, it is necessary to research how this substitution affects the various steps of the production system, including baking. During baking, one of the most significant processes is moisture loss. In this sense, the kinetic modeling of the moisture loss process parameters is mainly helpful in the food industry. The mathematical models of moisture loss processes are used to design new or improved baking systems or even control the process.

The Presence of Blood-Brain Barrier Modulates the Response to Magnesium Salts in Human Brain Organoids

Magnesium (Mg) is fundamental in the brain, where it regulates metabolism and neurotransmission and protects against neuroinflammation. To obtain insights into the molecular basis of Mg action in the brain, we investigated the effects of Mg in human brain organoids, a revolutionary 3D model to study neurobiology and neuropathology. In particular, brain organoids derived from human induced pluripotent stem cells were cultured in the presence or in the absence of an in vitro-generated blood–brain barrier (BBB), and then exposed to 1 or 5 mM concentrations of inorganic and organic Mg salts (Mg sulphate (MgSO₄); Mg pidolate (MgPid)). We evaluated the modulation of NMDA and GABAergic receptors, and BDNF. Our data suggest that the presence of the BBB is essential for Mg to exert its effects on brain organoids, and that 5 mM of MgPid is more effective than MgSO₄ in increasing the levels of GABA receptors and BDNF, and decreasing those of NMDA receptor. These results might illuminate novel pathways explaining the neuroprotective role of Mg.

Vitamin D Prevents High Glucose-Induced Lipid Droplets Accumulation in Cultured Endothelial Cells: The Role of Thioredoxin Interacting Protein

Vitamin D (VitD) exerts protective effects on the endothelium, which is fundamental for vascular integrity, partly by inhibiting free radical formation. We found that VitD prevents high glucose-induced Thioredoxin Interacting Protein (TXNIP) upregulation. Increased amounts of TXNIP are responsible for the accumulation of reactive oxygen species and, as a consequence, of lipid droplets. This is associated with increased amounts of triglycerides as the result of increased lipogenesis and reduced fatty acid oxidation. Remarkably, VitD rebalances the redox equilibrium, restores normal lipid content, and prevents the accumulation of lipid droplets. Our results highlight TXNIP as one of the targets of VitD in high glucose-cultured endothelial cells and shed some light on the protective effect of VitD on the endothelium.

Unveiling the basis of antiretroviral therapy-induced osteopenia: the effects of Dolutegravir, Darunavir and Atazanavir on osteogenesis

OBJECTIVES

Osteopenia is frequent in HIV-infected patients treated with antiretroviral therapy (ART) and has been linked to increased osteoclastogenesis. Little is known about the effects of ART on osteogenesis.

DESIGN

We investigated the effect on human mesenchymal stem cells (hMSC) and osteoblasts of Darunavir and Dolutegravir, the most highly used as anchor drugs within a three-drug regimen, and Atazanavir, which was widely utilized in the past.

RESULTS

We found that Atazanavir and Dolutegravir delay the osteogenic differentiation of hMSC, impair the activity of osteoblasts and inhibit their conversion into osteocytes, whereas Darunavir exerts no effect.

CONCLUSION

Atazanavir and Dolutegravir impair osteogenesis. It is essential to diagnose impaired osteogenesis early and to devise effective therapeutic interventions to preserve bone health in ART-treated HIV patients, putting it in the context of a correct antiretroviral combination.

Headaches and Magnesium: Mechanisms, Bioavailability, Therapeutic Efficacy and Potential Advantage of Magnesium Pidolate

Magnesium deficiency may occur for several reasons, such as inadequate intake or increased gastrointestinal or renal loss. A large body of literature suggests a relationship between magnesium deficiency and mild and moderate tension-type headaches and migraines. A number of double-blind randomized placebo-controlled trials have shown that magnesium is efficacious in relieving headaches and have led to the recommendation of oral magnesium for headache relief in several national and international guidelines. Among several magnesium salts available to treat magnesium deficiency, magnesium pidolate may have high bioavailability and good penetration at the intracellular level. Here, we discuss the cellular and molecular effects of magnesium deficiency in the brain and the clinical evidence supporting the use of magnesium for the treatment of headaches and migraines.

Mitophagy contributes to endothelial adaptation to simulated microgravity

Exposure to real or simulated microgravity is sensed as a stress by mammalian cells, which activate a complex adaptive response. In human primary endothelial cells, we have recently shown the sequential intervention of various stress proteins which are crucial to prevent apoptosis and maintain cell function. We here demonstrate that mitophagy contributes to endothelial adaptation to gravitational unloading. After 4 and 10 d of exposure to simulated microgravity in the rotating wall vessel, the amount of BCL2 interacting protein 3, a marker of mitophagy, is increased and, in parallel, mitochondrial content, oxygen consumption, and maximal respiratory capacity are reduced, suggesting the acquisition of a thrifty phenotype to meet the novel metabolic challenges generated by gravitational unloading. Moreover, we suggest that microgravity induced-disorganization of the actin cytoskeleton triggers mitophagy, thus creating a connection between cytoskeletal dynamics and mitochondrial content upon gravitational unloading.

The Contribution of EDF1 to PPARγ Transcriptional Activation in VEGF-Treated Human Endothelial Cells

Vascular endothelial growth factor (VEGF) is important for maintaining healthy endothelium, which is crucial for vascular integrity. In this paper, we show that VEGF stimulates the nuclear translocation of endothelial differentiation-related factor 1 (EDF1), a highly conserved intracellular protein implicated in molecular events that are pivotal to endothelial function. In the nucleus, EDF1 serves as a transcriptional coactivator of peroxisome proliferator-activated receptor gamma (PPARγ), which has a protective role in the vasculature. Indeed, silencing EDF1 prevents VEGF induction of PPARγ activity as detected by gene reporter assay. Accordingly, silencing EDF1 markedly inhibits the stimulatory effect of VEGF on the expression of FABP4, a PPARγ-inducible gene. As nitric oxide is a marker of endothelial function, it is noteworthy that we report a link between EDF1 silencing, decreased levels of FABP4, and nitric oxide production. We conclude that EDF1 is required for VEGF-induced activation of the transcriptional activity of PPARγ.

Magnesium Deprivation Potentiates Human Mesenchymal Stem Cell Transcriptional Remodeling

Magnesium plays a pivotal role in energy metabolism and in the control of cell growth. While magnesium deprivation clearly shapes the behavior of normal and neoplastic cells, little is known on the role of this element in cell differentiation. Here we show that magnesium deficiency increases the transcription of multipotency markers and tissue-specific transcription factors in human adipose-derived mesenchymal stem cells exposed to a mixture of natural molecules, i.e., hyaluronic, butyric and retinoid acids, which tunes differentiation. We also demonstrate that magnesium deficiency accelerates the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells. We argue that magnesium deprivation generates a stressful condition that modulates stem cell plasticity and differentiation potential. These studies indicate that it is possible to remodel transcription in mesenchymal stem cells by lowering extracellular magnesium without the need for genetic manipulation, thus offering new hints for regenerative medicine applications.

Trillium™ Biopassive Surface: A New Biocompatible Treatment for Extracorporeal Circulation Circuits

139 patients undergoing cardiac surgery were included in a prospective, randomized trial. Patients were randomly allocated to receive cardiopulmonary bypass (CPB) with Trillium™ Biopassive Surface (TBS Group) coated oxygenators or conventional circuits (control group).

112 patients were studied with respect to postoperative biochemical profile; a subgroup of 27 patients was studied with respect to perioperative complement (C3a) activation.

Patients in the TBS group demonstrated a significantly lower white blood cell count at the end of the operation (p=0.036) and a significantly higher platelet count the day after the operation (p=0.023) when compared to the control group. C3a was significantly higher (p=0.02) in the TBS group after 30 minutes of CPB, but the C3a increase after protamine administration was significantly less pronounced in the TBS group vs. the control group.

Further studies involving platelet and leukocyte activation are required to better elucidate the action of this new coating in the setting of routine CPB.

Femtograms of Interferon-γ Suffice to Modulate the Behavior of Jurkat Cells: A New Light in Immunomodulation

Since interferon-γ (IFN-γ) tunes both innate and adaptive immune systems, it was expected to enter clinical practice as an immunomodulatory drug. However, the use of IFN-γ has been limited by its dose-dependent side effects. Low-dose medicine, which is emerging as a novel strategy to treat diseases, might circumvent this restriction. Several clinical studies have proved the efficacy of therapies with a low dose of cytokines subjected to kinetic activation, while no in vitro data are available. To fill this gap, we investigated whether low concentrations, in the femtogram range, of kinetically activated IFN-γ modulate the behavior of Jurkat cells, a widely used experimental model that has importantly contributed to the present knowledge about T cell signaling. In parallel, IFN-γ in the nanogram range was used and shown to activate Signal transducer and activator of transcription (STAT)-1 and then to induce suppressor of cytokine signaling-1 (SOCS-1), which inhibits downstream signaling. When added together, femtograms of IFN-γ interfere with the transduction cascade activated by nanograms of IFN-γ by prolonging the activation of STAT-1 through the downregulation of SOCS-1. We conclude that femtograms of IFN-γ exert an immunomodulatory action in Jurkat cells.

Silver Nanoparticles in Orthopedic Applications: New Insights on Their Effects on Osteogenic Cells

Infections of orthopedic implants are associated with high morbidity. The emergence of antibiotic resistant strains and the tendency of microbes to form biofilms on orthopedic devices prompt the individuation of novel antimicrobial agents. Silver nanoparticles represent an interesting alternative, but their effects on bone cells need to be clarified. We focused on osteoblast-like cells and on bone marrow-mesenchymal stem cells and found that these cells are rather resistant to the cytotoxic effects of silver nanoparticles, with a half maximal inhibitory concentration around 25 µg/mL as detected by MTT assay. Within a month of treatment, osteoblast-like cells adapt to the presence of the nanoparticles by upregulating hsp70 as shown by western blot. Hsp70 overexpression correlates with the restoration of normal cell proliferation. No alterations in the extent and time requirements were detected in mesenchymal stem cell induced to differentiate in osteoblasts in the presence of silver nanoparticles. Because the concentrations of silver nanoparticles which show antimicrobial activity are lower than those exerting toxic effects on bone-forming cells in vitro, we suggest that silver nanoparticles might represent a challenging tool to fight infections in orthopedic implants.

Culture of human cells in experimental units for spaceflight impacts on their behavior

Because space missions produce pathophysiological alterations such as cardiovascular disorders and bone demineralization which are very common on Earth, biomedical research in space is a frontier that holds important promises not only to counterbalance space-associated disorders in astronauts but also to ameliorate the health of Earth-bound population. Experiments in space are complex to design. Cells must be cultured in closed cell culture systems (from now defined experimental units (EUs)), which are biocompatible, functional, safe to minimize any potential hazard to the crew, and with a high degree of automation. Therefore, to perform experiments in orbit, it is relevant to know how closely culture in the EUs reflects cellular behavior under normal growth conditions. We compared the performances in these units of three different human cell types, which were recently space flown, i.e. bone mesenchymal stem cells, micro- and macrovascular endothelial cells. Endothelial cells are only slightly and transiently affected by culture in the EUs, whereas these devices accelerate mesenchymal stem cell reprogramming toward osteogenic differentiation, in part by increasing the amounts of reactive oxygen species. We conclude that cell culture conditions in the EUs do not exactly mimic what happens in a culture dish and that more efforts are necessary to optimize these devices for biomedical experiments in space. Impact statement Cell cultures represent valuable preclinical models to decipher pathogenic circuitries. This is true also for biomedical research in space. A lot has been learnt about cell adaptation and reaction from the experiments performed on many different cell types flown to space. Obviously, cell culture in space has to meet specific requirements for the safety of the crew and to comply with the unique environmental challenges. For these reasons, specific devices for cell culture in space have been developed. It is important to clarify whether these alternative culture systems impact on cell performances to allow a correct interpretation of the data.

Prednisolone inhibits SaOS2 osteosarcoma cell proliferation by activating inducible nitric oxide synthase

AIM: To investigate the effect of prednisolone, a synthetic glucocorticoid used in inflammatory diseases, on the growth of cultured osteosarcoma cells.

METHODS: Two osteosarcoma cell lines with different degree of differentiation were used. SaOS2 show a rather mature phenotype, while U2OS are negative for almost all osteoblastic markers. The cells were exposed to different concentrations of prednisolone (1-9 μmol/L) with or without antioxidants or the inhibitor of inducible nitric oxide synthase (iNOS) l-N⁶-(iminoethyl)-lysine-HCl (L-NIL). Cell growth was assessed by counting viable cells. The production of nitric oxide (NO) was measured in the conditioned media by the Griess method. The production of reactive oxygen species was quantified using 2’-7’-dichlorofluorescein diacetate. Western blot with specific antibodies against NOSs was performed on cell extracts.

RESULTS: Prednisolone inhibited SaOS2 cell growth in a dose dependent manner. No significant effects were observed in U2OS. The inhibition of SaOS2 growth is not due to oxidative stress, because antioxidants do not rescue cell proliferation. Since high concentrations of NO inhibit bone formation, we also measured NO and found it induced in SaOS2, but not in U2OS, exposed to prednisolone, because of the upregulation of iNOS as detected by western blot. Therefore, we treated SaOS2 with prednisolone in the presence or in the absence of L-NIL. L-NIL prevented NO release induced by prednisolone at all the concentrations apart from 9 μmol/L. At the same concentrations, we found that L-NIL rescued SaOS2 growth after exposure to prednisolone. In U2OS cells, prednisolone did not induce NO production nor affected cell growth. All together, these data indicate that a link exists between increased amounts of NO and growth inhibition in response to prednisolone in SaOS2.

CONCLUSION: Prednisolone inhibited SaOS2 proliferation by increasing the release of NO through the upregulation of iNOS, while no effect was exerted on U2OS.

Impact of simulated microgravity on human bone stem cells: New hints for space medicine

Bone loss is a well known early event in astronauts and represents one of the major obstacle to space exploration. While an imbalance between osteoblast and osteoclast activity has been described, less is known about the behavior of bone mesenchymal stem cells in microgravity. We simulated microgravity using the Random Positioning Machine and found that mesenchymal stem cells respond to gravitational unloading by upregulating HSP60, HSP70, cyclooxygenase 2 and superoxyde dismutase 2. Such an adaptive response might be involved in inducing the overexpression of some osteogenic transcripts, even though the threshold to induce the formation of bone crystal is not achieved. Indeed, only the addition of an osteogenic cocktail activates the full differentiation process both in simulated microgravity and under static 1G-conditions. We conclude that simulated microgravity alone reprograms bone mesenchymal stem cells towards an osteogenic phenotype which results in complete differentiation only after exposure to a specific stimulus.

Magnesium homeostasis in colon carcinoma LoVo cells sensitive or resistant to doxorubicin

Neoplastic cells accumulate magnesium, an event which provides selective advantages and is frequently associated with TRPM7overexpression. Little is known about magnesium homeostasis in drug-resistant cancer cells. Therefore, we used the colon cancer LoVo cell model and compared doxorubicin-resistant to sensitive cells. In resistant cells the concentration of total magnesium is higher while its influx capacity is lower than in sensitive cells. Accordingly, resistant cells express lower amounts of the TRPM6 and 7, both involved in magnesium transport. While decreased TRPM6 levels are due to transcriptional regulation, post-transcriptional events are involved in reducing the amounts of TRPM7. Indeed, the calpain inhibitor calpeptin markedly increases the levels of TRPM7 in resistant cells. In doxorubicin-sensitive cells, silencing TRPM7 shifts the phenotype to one more similar to resistant cells, since in these cells silencing TRPM7 significantly decreases the influx of magnesium, increases its intracellular concentration and increases resistance to doxorubicin. On the other hand, calpain inhibition upregulates TRPM7, decreases intracellular magnesium and enhances the sensitivity to doxorubicin of resistant LoVo cells. We conclude that in LoVo cells drug resistance is associated with alteration of magnesium homeostasis through modulation of TRPM7. Our data suggest that TRPM7 expression may be an additional undisclosed player in chemoresistance.

Short- and long-term effects of silver nanoparticles on human microvascular endothelial cells

AIM: To study the response to silver nanoparticles (Ag NP) of human microvascular endothelial cells, protagonists of angiogenesis.

METHODS: We cultured human microvascular endothelial cells and endothelial colony-forming cells in their corresponding growth medium. Stock solutions of Ag NP were prepared in culture medium and sonicated before use. They were added at different concentrations and for different times to culture media. The toxicity of Ag NP was investigated by measuring the reduction of yellow tetrazolium salt to dark purple formazan (MTT assay) at 575 nm. After staining with trypan blue, cell proliferation was assessed by counting viable cells. The lactate dehydrogenase leakage assay was performed on culture media by following the oxidation of NADH to NAD+ and monitoring the reaction kinetically at 340 nm. Reactive oxygen species production was quantified using 2’-7’-dichlorofluorescein diacetate. The alkaline comet assay was performed after mixing the cells with low melting-point agarose. Electrophoresis was then conducted and the samples were stained with ethidium bromide and analyzed with a fluorescence microscope.

RESULTS: Ag NP are cytotoxic in a dose and time dependent fashion for HMEC. At high concentrations, Ag NP determine loss of membrane integrity as demonstrated by the increased activity of lactate dehydrogenase in the culture medium. Ag NP rapidly stimulate the formation of free radicals. However, pre-incubation with Trolox, apocynin, or N-acetyl-L-cysteine, antioxidants which have different structure and act through different mechanisms, is not sufficient to prevent cytotoxicity. Ag NP also induce DNA damage dose-dependently, as shown by comet assay. When exposed to sublethal concentrations of Ag NP for long times, the cells remain viable but are growth retarded. Interestingly, removal of Ag NP partially rescues cell growth. Also genotoxicity is reversible upon removal of Ag NP from culture medium, suggesting that no permanent modifications occur. It is noteworthy that Ag NP are cytotoxic and genotoxic also for endothelial progenitors, in particular for endothelial colony-forming cells, which participate to angiogenesis.

CONCLUSION: Silver nanoparticles are cytotoxic and genotoxic for human microvascular endothelial cells and might become a useful tool to control excessive angiogenesis.

Magnesium and osteoporosis: current state of knowledge and future research directions

A tight control of magnesium homeostasis seems to be crucial for bone health. On the basis of experimental and epidemiological studies, both low and high magnesium have harmful effects on the bones. Magnesium deficiency contributes to osteoporosis directly by acting on crystal formation and on bone cells and indirectly by impacting on the secretion and the activity of parathyroid hormone and by promoting low grade inflammation. Less is known about the mechanisms responsible for the mineralization defects observed when magnesium is elevated. Overall, controlling and maintaining magnesium homeostasis represents a helpful intervention to maintain bone integrity.

The Use of Cortical Heterologous Sheets for Sinus Lift Bone Grafting: A Modification of Tulasne's Technique with 7-Year Follow-up

In this article, the authors describe their experience with using cortical deantigenated equine bone sheets in sinus lift grafting procedures performed on 23 patients. The technique employed resembles that described by Tulasne but avoids the need for using harvested calvaria bone and introduces some additional operating variants. The use of heterologous cortical bone sheets effectively managed even large lacerations of the Schneiderian membrane and allowed for immediate stabilization of the heterologous bone granules. Average histomorphometric values for bone cores collected six months after grafting, at the time of implant placement, were: newly formed bone tissue 43.9±4.2%, residual bone substitute 7.4±1.4%, medullary spaces 48.7±4.0%. At seven year follow-up, clinical and radiographic examination indicated that the use of the bone sheets preserved the regenerated bone volume. In conclusion, the use of heterologous cortical bone sheets in association with granular bone graft material enabled long-term stabilization of the graft material and effective management of intra-surgical complications.

Cardiac response to robotic assisted locomotion in normal subjects: a preliminary study

Robotic assisted locomotion systems are recently gaining appreciation and diffusion as useful methods to rehabilitate individuals with lost sensorimotor function. Our aim was to evaluate potential changes in the autonomic nervous system activity (by ECG and spectral analysis), due to the experimental protocol, which include suspension of the subject to be instrumented on the system. A group of 10 normal subjects was studied during the rehabilitation protocol. Results showed a significant tachycardia and a reduced variance, during orthostatic stress induced by the suspension phase in comparison with sitting baseline condition but no significant increase of LF normalized power as it would be expected during a sympathetic activation.

Reconstructive Technique for Partial Penile Amputation

Partial or total penile amputation with resection of the corpora cavernosa and the urethra is a common and effective surgical procedure used to treat squamous cell cancer infiltrating the deep tissues of the penis. We describe an original method that allows for an aesthetic and functional restoration of the partially or total amputated penis.

Surgical technique

We performe a reconstructive technique for partial penile amputation by releasing the scarring tissue adhesions with cavernosal lysis and by advancing the penile stump with dissection of the suspensory ligament; implantation of soft but axially firm endocavernosal elastomer prostheses to maintain the corpora cavernosa extended; placement of split-thickness skin grafts to cover the shaft skin defects and glanduloplasty with oral mucosa grafting. In cases of total penile amputation, the method begins with the reconstruction of a new phallus using a rectoabdominalis flap; the new penis is then covered with split-thickness skin grafts and finally, at a later date, soft but axially firm endocavernosal elastomer prostheses are implanted.

Results

The success rate as be excellent compared with other complex reconstructive and remodelling procedures for the penis and the glans after partial or total penectomy described by several authors.

Conclusions

In cases of total or subtotal penile amputation, the use of our techniques provides satisfactory aesthetic and functional results, thus we consider it to be a simple solution since it is not too invasive, it is quick and can be carried out by urologists without recourse to sophisticated microsurgery techniques.

Oxygenation Status of the Cavernosal Tissue after the Direct Action of the Vacuum Device

This study aims at comparing the oxygenation status of the cavernosal tissue after the direct action of the Vacuum device (VD) preceded or not by administration of Sildenafil. Patients and methods. We enrolled thirty patients who had undergone perineal radical prostatectomy. After four weeks from surgery we evaluated oxygen pressure (pO2), carbon dioxide pressure (pCO2) and O2 saturation in cavernosal blood. The pts were divided in 2 groups: 15 pts used only Vacuum device (first group), while the other 15 took Sildenafil 50 mg one hour before the exercise with VD (second group) for approximately 30 minutes without constriction band. Cavernous blood gas analyses pre- e post-exercising with the VD were repeated at the end of the complete 3-month rehabilitation program. The data obtained were processed by statistical analysis using the Student t test.

Results

During flaccidity at baseline, average levels of pO2, pCO2 and O2% saturation rates were respectively 30.07+/-2.91, 39.60+/-6.47, and 65.93+/-2.15 in the first group and 31.20+/-8.1, 42.64+/-7.64 and 52.87+/-8.95 in the second group. Mean values of pO2 rates increased after both treatments with higher oxygenation levels in the second group. At the end of the study pO2 and O2 saturation levels in the second group were found to be 68.5+/-6.87 (p>0.05) and 92.8+/- 2.66 (n.s.) versus levels of 63.8+/- 4.61 and 91.6+/-2.79 in the first group. No significant variations were found in partial CO2 pressure between the two groups (38.13+/-3.52 vs 38. 13+/-6.62).

Conclusions

In patients presenting with ED after radical prostatectomy, treatment with exercising of erectile tissue by means of an intermittent Vacuum device without constriction band can locally improve oxygenation levels. The addition of Sildenafil offers a further increase of oxygenation levels in the cavernosal tissue.

Nephron Sparing Surgery with the Ultrasonic Scalpel

Surgical resection remains the cornerstone of treatment renal cell carcinoma. In the last 15 years a better understanding of tumor biology and the early diagnosis permitted an evolution of the surgical treatment towards a minimal invasive approach by nephron-sparing surgery. Together with absolute and relative indications, nephron-sparing surgery is performed also as an elective indication, in patients with small, localized, often incidental tumors and a normal controlateral kidney. The oncological outcome in these cases is identical with that of radical nephrectomy. In order to achieve a complete tumor resection with the maximal preservation of unaffected renal parenchyma, tumor enucleation is the best technique when feasible. With the use of the harmonic scalpel, clamping of the renal pedicle and renal ischemia can be avoided in most of the cases during enucleation of small tumors, while the thermal damage in the remaing renal parenchyma is minimal.

A new technique for augmentation phalloplasty: albugineal surgery with bilateral saphenous grafts--three years of experience

OBJECTIVES

Penile augmentation surgery is a highly controversial issue due to the low level of standardisation of surgical techniques. The aim of the study is to illustrate a new technique to solve the problem of enlarging the penis by means of additive surgery on the albuginea of the corpora cavernosa, guaranteeing a real increase in size of the erect penis.

METHODS

Between 1995 and 1997, 39 patients who requested an increase in the diameter of their penises underwent augmentation phalloplasty with bilateral saphena grafts. The patients considered eligible for surgery were patients with either hypoplasia of the penis or functional penile dysmorphophobia. All the patients included in our study presented normal erection at screening. The average penis diameter in a flaccid state and during erection was found to be 2.1cm (1.6-2.7 cm) and 2.9 cm (2.2-3.7 cm), respectively. Before surgery the patients were informed of the experimental nature of the surgical procedure. The increase in volume of the corpora cavernosa was achieved by applying saphena grafts to longitudinal openings made bilaterally in the albuginea along the whole length of the penis.

RESULTS

No major complications and specifically no losses of sensitivity of the penis or erection deficiencies occurred during the post-operative follow-up period. All the patients resumed their sexual activity in 4 months. A measurement of the penile dimensions was carried out 9 months after surgery. No clinical meaningful increases in the diameter of the flaccid penis were documented. The average penis diameter during erection was found to be 4.2 cm (3.4-4.9) with post-surgery increases in diameter varying from 1.1 to 2.1cm (p<0.01).

CONCLUSIONS

The penile enlargement phalloplasty technique with albuginea surgery suggested by the authors definitely is indicated for increasing the volume of the corpora cavernosa during erection. Albuginea surgery with saphena grafts has been found to be free from aesthetic and functional complications with excellent patient satisfaction.

Closed, phosphorylcholine-coated circuit and reduction of systemic heparinization for cardiopulmonary bypass: the intraoperative ECMO concept

Cardiopulmonary bypass with heparin-bonded circuits reduces systemic heparinization which is associated to a better clinical outcome in cardiac operations. In the present study, a novel biocompatible treatment, based on a phosphorylcholine coating without heparin, has been used to reduce systemic heparinization during cardiopulmonary bypass. Sixty patients underwent coronary revascularization with a fully phosphorylcholine-coated circuit. The circuit was entirely closed; suctions from the field were separated during the cardiopulmonary bypass time. A low systemic heparinization protocol based on half the loading dose of heparin (150 IU/kg) and a target activated clotting time of 320 seconds was applied. No thrombus formation inside the extracorporeal circulation circuit occurred; in-hospital mortality was absent. One patient (1.6%) had a postoperative myocardial infarction and 2 (3.3%) were surgically revised due to bleeding. Homologous blood transfusion rate was 11.6%, postoperative bleeding was 310 +/- 136 ml. If compared to patients treated with heparin-coated circuits and low systemic heparinization, these patients have better platelet count preservation and lower postoperative bleeding. The low thrombogenicity of phosphorylcholine-treated surfaces, despite the absence of surface-immobilized heparin, allows a safe reduction of systemic heparinization in the setting of an ECMO-like intraoperative cardiopulmonary - bypass. This intraoperative ECMO approach offers promising results in terms of clinical outcome after coronary revascularization operations.

Risk factors for fatal myocardial infarction after coronary bypass graft surgery

BACKGROUND AND OBJECTIVE

The incidence and clinical impact of perioperative myocardial infarction during coronary artery bypass graft surgery vary greatly depending upon the diagnostic criteria applied. Fatal perioperative myocardial infarction has a less arguable diagnosis and clinical impact. The aim of this paper is to find out the risk factors for fatal myocardial infarction after coronary surgery.

METHODS

Data from 1561 consecutive patients, who underwent coronary revascularization during a 10-month period, have been retrospectively analysed. After an univariate analysis for pre- and intraoperative risk factors, a multivariate model (logistic regression analysis) was settled.

RESULTS

Preoperative use of subcutaneous/intravenous heparin, a heparin sensitivity index < 1.3 and need for a thromboendarterectomy of the left anterior descending coronary artery are independent risk factors for fatal myocardial infarction. The relative risk for fatal myocardial infarction was about 2 in the case of preoperative heparin use or heparin sensitivity index < 1.3 and 5.5 in the case of thromboendarterectomy of the left anterior descending coronary artery.

CONCLUSIONS

In patients undergoing coronary artery bypass surgery, preoperative anticoagulation management with heparin may represent a risk factor for fatal myocardial infarction. Patterns of heparin resistance, whether or not due to heparin pretreatment, seem to be closely related to fatal myocardial infarction.

Trillium biopassive surface: a new biocompatible treatment for extracorporeal circulation circuits

139 patients undergoing cardiac surgery were included in a prospective, randomized trial. Patients were randomly allocated to receive cardiopulmonary bypass (CPB) with Trillium Biopassive Surface (TBS Group) coated oxygenators or conventional circuits (control group). 112 patients were studied with respect to postoperative biochemical profile; a subgroup of 27 patients was studied with respect to perioperative complement (C3a) activation. Patients in the TBS group demonstrated a significantly lower white blood cell count at the end of the operation (p=0.036) and a significantly higher platelet count the day after the operation (p=0.023) when compared to the control group. C3a was significantly higher (p=0.02) in the TBS group after 30 minutes of CPB, but the C3a increase after protamine administration was significantly less pronounced in the TBS group vs. the control group. Further studies involving platelet and leukocyte activation are required to better elucidate the action of this new coating in the setting of routine CPB.

Postoperative analgesia for early extubation after cardiac surgery. A prospective, randomized trial

BACKGROUND

Early extubation after cardiac surgery is a procedure recently gaining interest due to its ability to shorten intensive care unit and hospital stay and to limit the operation-related costs. Its use, however, raised new problems in terms of pain control in the early postoperative course, due to the need for limiting opioid analgesia. This study deals with non-opioid pain control after cardiac surgery and early extubation.

METHODS

Prospective, randomized trial aimed to investigate the effectiveness of three intravenous analgesic drugs (ketorolac, 60 mg i.v.; propacetamol, 2 g i.v.; tramadol, 200 mg i.v.) for the management of postoperative pain in early extubated cardiac surgical patients. Each treatment group comprised 20 patients.

RESULTS

The pain assessment (5-item verbal scale) demonstrated a significant (p < 0.05) lower value in patients treated with ketorolac vs propacetamol, while patients treated with tramadol did not significantly differ from the other two groups. There was a significantly (p < 0.05) higher rate of patients with severe pain in propacetamol group. Patients treated with tramadol had a significantly (p < 0.01) higher PaCO2 (48 +/- 6 mmHg) versus patients treated with ketorolac (43.4 +/- 3.7 mmHg) or propacetamol (42.9 +/- 3.4 mmHg).

CONCLUSIONS

Tramadol and ketorolac seem to be the best options for treating postoperative pain in the specific setting of early extubation after cardiac surgery; high doses of tramadol may result in a significant even if clinically not relevant respiratory depression.

Predictors for heparin resistance in patients undergoing coronary artery bypass grafting

Heparin resistance (HR) is a common event in cardiac operations. At present, no clear recognition of the risk factors for HR has been reached. The aim of this study was to determine a predictive model for HR, based on the preoperative patient's profile. Two hundred consecutive patients scheduled for elective coronary artery bypass operations were enrolled in a prospective trial. Demographics, type of preoperative anticoagulation therapy and preoperative coagulation profile were collected and statistically analysed with respect to the evidence of a HR. Heparin resistance was defined as at least one activated clotting time < 400 s after heparinization and/or the need for purified antithrombin III (AT-III) administration. With a multivariate analysis we could identify five predictors for HR: AT-III < or = 60%; preoperative subcutaneous heparin therapy; intravenous heparin therapy; platelet count > or = 300000 cells/mm3; age > or = 65 years. We conclude that HR is a predictable event. In the presence of all the risk factors, the likelihood of HR is 99%; in the absence of all of them, it is 10%. Predicting HR allows us to apply many possible therapeutic strategies.

Gabexate mesilate and antithrombin III for intraoperative anticoagulation in heparin pretreated patients

Thirty patients scheduled for elective myocardial revascularization and having undergone preoperative heparin treatment have been admitted to this prospective, randomized study. The aim of the study was to test two different strategies for preserving circulating antithrombin III (AT-III) during cardiopulmonary bypass. Patients in the control group (group C, n = 10) were treated with a standard heparinization (300 IU/kg). Patients in group A (n = 10) received the same management plus two doses of purified antithrombin III (1000 IU each). Patients in group GA received 200 IU/kg heparin and a continuous infusion of heparin (100 IU/kg/h) and gabexate mesilate (2 mg/kg/h) plus the same dose of antithrombin III as group A. Both group A and group GA demonstrated a preservation of circulating AT-III when compared to group C; this effect was more pronounced in group GA. The total heparin dosage was less in group GA than in groups A and C. Purified AT-III administration is recommended in heparin pretreated patients; the addition of gabexate mesilate to this protocol decreases the heparin requirement and increases the AT-III preservation.

Obesity and coronary artery surgery

OBJECTIVE

To assess whether obesity is a risk factor for morbidity and mortality in patients undergoing elective coronary artery revascularization.

DESIGN

Prospective, clinical study.

SETTING

University hospital.

PARTICIPANTS

Three hundred forty-five consecutive patients who underwent elective coronary revascularization with cardiopulmonary bypass and without associated procedures.

INTERVENTIONS

Patients were assigned to the obese group if their body mass index was greater than 30 for men and 28.6 for women, according to the World Health Organization indications.

MEASUREMENTS AND MAIN RESULTS

Preoperative and intraoperative variables were collected and checked for homogeneity of the groups. Postoperative outcome was assessed on the basis of intubation time, intensive care unit (ICU) and postoperative hospital stay, mortality rate, and incidence of transfusions, reoperations, low-output syndrome, minor and major neurologic dysfunction, minor and major lung dysfunctions, renal dysfunction, and superficial and deep infections. The effect of obesity on postoperative outcome was tested with a multivariate logistic regression analysis. Obese and control patients had the same intubation time and ICU and postoperative hospital stay. Mortality and all major complications occurred with the same incidence in the two groups. Obese patients had a significantly (p < 0.05) greater rate of superficial infections and more (24.1% v 7.4%; p < 0.001) minor lung complications. Conversely, they had a significantly lower transfusion rate (27.5% v42.7%; p < 0.01).

CONCLUSION

Obese patients had only minor complications after coronary artery surgery. The large body surface area because of obesity protects them against the hemodilution-related transfusion risk.

Diabetes and complications after cardiac surgery: comparison with a non-diabetic population

Diabetes is a well-recognized independent risk factor for mortality due to coronary artery disease. When diabetic patients need cardiac surgery, either coronary-aortic by-pass (CABP) or valve operations (VO), the presence of diabetes represents an additional risk factor for these major surgical procedures. Because of controversial data on mortality rates and post-operative complications in diabetic patients, probably due to not exactly comparable groups of patients, this retrospective study aimed to compare two homogeneous populations, which were different only for the presence or absence of diabetes. We studied 700 patients undergoing cardiac surgery: 350 with and 350 without diabetes, mean age 62 +/- 9 years (67% males); 441 underwent CABP and 259 VO. Apart from the diabetes, the two groups were strictly matched for age, body mass index, concomitant pathologies and smoking habits, except for previous neurological injuries (more frequent in diabetic patients), and for a slightly lower ejection fraction in the diabetic group. Intra- and post-operative complications or events were evaluated carefully: death, number staying in post-operative intensive care unit (ICU), renal, hepatic and respiratory complications, necessity for reoperation and hemotransfusions. Anesthesia and surgical procedures (including extra-corporeal circulation techniques) remained substantially unchanged over the period of recruitment of patients (1996-1998) and applied equally to both groups of patients. All diabetic patients were treated with insulin by using standard procedures in order to optimize metabolic control. Diabetic patients in our study, did not show higher rates of mortality in comparison with non-diabetic patients, but had more total neurological complications, more renal complications, a higher re-opening rate, more prolonged ICU stay, and they needed more blood transfusions. Diabetes remains an independent risk factor for these events even in a multivariate logistic regression model analysis. In the subgroup of diabetic patients who underwent CABP a higher rate of renal dysfunction, re-opening, need for hemotransfusions and prolonged ICU stay were confirmed. In the subgroup of diabetic patients undergoing VO we found a higher rate of renal dysfunction, reopening, prolonged ICU stay and major lung complications. In conclusion, diabetes does not seem to increase the mortality rates of cardiac surgery, but diabetic patients undergoing CABP have, on the basis of the relative risk evaluation, a 5-fold risk for renal complications, a 3.5-fold risk for neurological dysfunction, a double risk of being hemotransfused, reoperated or being kept 3 or more days in the ICU in comparison with non-diabetic patients. Moreover, diabetic patients undergoing VO have a 5-fold risk of being affected by major lung complications.

[Andrologic surgery]

The need of an economic and social low costs drive more and more surgeons towards the day surgery. The always growing diffusion of local anesthetic supports this trend. The drugs used as local anaesthetics are: carbocaine, procaine, lidocaine and bipivacaine. The Day Surgery can be largely employed in the therapy of andrological pathologies. In fact the anatomical placement of male genital apparatus allows easy possibilities of anaesthetical and surgical approach. It is so possible perform the following operations: meatotomy, section and plasty of fraenum, extirpation of Papovavirus lesions, circumcision, paraphymosis setting, corpora cavernosa drainage in priapism, section and ligation of deep dorsal vein, corporopexi, glandulopexi, cavernous crural plication, endocavernous penile prosthesis' implant, congenital or acquired penile recurvatum correction, blandulectomy, hepidydimis' cyst excision, testicle's biopsy, subcapsular orchiectomy sec. Higgins, testicular prosthesis' implant, resection and eversion of vaginal tunic of testicle in hydrocele's therapy, vasotomy and section and ligation of internal spermatic vein in varicocele's surgery. The Authors describe the anaesthetical and surgical techniques for bring forward these operations in Day Surgery.

[Varicocele and its repercussion on infertility. Indications and limitations of surgical intervention]

According to different Authors, varicocele incidence in unselected population fluctuates from 8 to 22% but in selected population affected by sterility incidence ranges from 21 to 39%. However other Authors have demonstrated that about 50% of patients suffering from varicocele have semen alterations. Various mechanisms have been suggested for testicular dysfunction associated with varicocele: intrascrotal hyperthermia, reflux of renal and adrenal metabolites from the renal vein and hypoxia. The most important semen alterations are observed in patients suffering from grade 2 and 3 varicocele and especially these patients must undergo surgical operation. According to recent findings, better results about the improvement of semen quality are obtained by operating children in puberal age. This clinical approach allows a prevention of testicular hypotrophy or, when this is already present, its reversibility. Varicocele surgical treatment makes use of traditional techniques microsurgical or not and mininvasive techniques. After renouncing of intrascrotal varicocelectomy, traditional techniques provide ligature and section of ectasic spermatic veins, after a surgical high (at level of the internal inguinal ring) or low (over inguinal canal) skin incision. Microsurgery allows recognition and protection of lymphatic and arterial vessels and execution of microsurgical anastomosis between venous spermatic and ileo-femoral circle vessels, when this is necessary. Internal spermatic vessels and vas deferens can be visualized through the laparoscope and so laparoscopic varicocele treatment was suggested. These new techniques and traditional operation are burdened with the same percentage of relapses but in laparoscopic procedure complications are more important. Recently radiographic occlusion techniques are also utilized (internal spermatic vein retrograde scleroembolization); the percentage of relapses is between 4 and 11%, with no risk of postvaricocelectomy hydrocele but with risk of loss of kidney (migration of the ballon or coil into the renal vein). Surgical treatment of varicocele produces a significant improvement in semen analysis in 60 to 80 per cent of patients affected by testicular dysfunction. Pregnancy rates after varicocelectomy are including from 20 to 60 per cent with most series averaging about 35 per cent.

Retroperitoneal haemorrhage secondary to spontaneous rupture of unknown renal cell carcinoma

We report a case of massive spontaneous retroperitoneal haemorrhage from the rupture of an unknown, small renal cell carcinoma. The clinical presentation and management modalities are discussed.

Diagnostic strategies for the early detection of prostatic cancer

— We carried out an investigational study of early detection of prostate carcinoma, using digital rectal examination (DRE) and serum prostate specific antigen (PSA). We determined the detection rate and some profiles of the carcinoma detected by screening in men from 50 to 80 years old. The detection rate was 2.3% in 1345 participants. In 20 men (64.5%) the disease was T1c or T2 and in 16 patients we performed radical prostatectomy.

Ureteral obstruction associated with prostate cancer: the outcome after ultrasonographic percutaneous nephrostomy

We retrospectively reviewed the outcome of 28 prostate cancer patients with ureteral obstruction treated by percutaneous nephrostomy. The over-all survival was 60% at 1 year and 32% at 2 years. The 1 and 2 years survival rates of 13 patients with no prior hormonal therapy were 70 and 45%, respectively, while those of patients who had previously received hormonal therapy were 46 and 17% respectively. Of 10 patients who had severe renal failure before percutaneous nephrostomy (serum creatinine greater than or equal to 7 mg per dl), 8 had an adequate return of renal function (serum creatinine less than 3 mg pe dl) after drainage and 55% survived more than 1 year, cutaneous nephrostomy is safe and effective in relieving ureteral obstruction and reasonable survival can be achieved even in patient with renal failure. Percutaneous nephrostomy should be considered strongly in these patients.

[Non-surgical therapy of impotence: infiltration, iontophoresis, ultrasound, laser]

Surgical therapy is the only useful correction in congenital fibrosis or in hypoplasia of the 'corpora cavernosa', associated with hypospadia or not. On the contrary in not congenital fibrosis of the 'corpora cavernosa' (Peyronie's disease, consequences of priapism, or trauma, complications of pharmaco-prosthesis) are allowed pharmaco-physical treatments (infiltrations, ionophoresis, ultrasound, laser). Pharmaco-physical therapy can be used as the only treatment, which is often resolutive, but it is also useful before or after the surgical operation of the 'corpora cavernosa'. These diseases can give disorders of the erection, until complete impotence is reached. In fact the erectile tissue can't expand, because of the rising fibrosclerosis. Among acquired fibrosis of corpora cavernosa I.P.P. has surely the greatest recurrent: the consistency of our series made possible to achieve significant results with a unified therapeutical protocol. The same management was applied in other, less frequent, penile fibrosis, always with full positive results even if on a small number of patients. We are evaluating a new drug (defibrotide) in the treatment of cavernosal vasculitis. Another one (hyaluronidase) associated to orgotein, could improve its effect against inflammation especially in chronic evolutions. Besides new treatments, we emphasize the prevention of iatrogenic fibrosis with particular regard to cavernous pharmaco-infusions by autoinjections: the training of the patient and the safety of the autoinjectors must be carefully checked by the andrologist to decrease a large amount of complications.