Neuroprotective and neurodegenerative effects of the chronic expression of tumor necrosis factor α in the nigrostriatal dopaminergic circuit of adult mice.

Tumor necrosis factor (TNF)-α, a pro-inflammatory cytokine, has been implicated in both neuronal death and survival in Parkinson's disease (PD). The substantia nigra (SN), a CNS region affected in PD, is particularly susceptible to inflammatory insults and possesses the highest density of microglial cells, but the effects of inflammation and in particular TNF-α on neuronal survival in this region remains controversial. Using adenoviral vectors, the CRE/loxP system and hypomorphic mice, we achieved chronic expression of two levels of TNF-α in the SN of adult mice. Chronic low expression of TNF-α levels reduced the nigrostriatal neurodegeneration mediated by intrastriatal 6-hydroxydopamine administration. Protective effects of low TNF-α level could be mediated by TNF-R1, GDNF, and IGF-1 in the SN and SOD activity in the striatum (ST). On the contrary, chronic expression of high levels of TNF-α induced progressive neuronal loss (63% at 20 days and 75% at 100 days). This effect was accompanied by gliosis and an inflammatory infiltrate composed almost exclusively by monocytes/macrophages. The finding that chronic high TNF-α had a slow and progressive neurodegenerative effect in the SN provides an animal model of PD mediated by the chronic expression of a single cytokine. In addition, it supports the view that cytokines are not detrimental or beneficial by themselves, i.e., their level and time of expression among other factors can determine its final effect on CNS damage or protection. These data support the view that new anti-parkinsonian treatments based on anti-inflammatory therapies should consider these dual effects of cytokines on their design.

Adenovirus serotype 5 hexon is critical for virus infection of hepatocytes in vivo.

Human species C adenovirus serotype 5 (Ad5) is the most common viral vector used in clinical studies worldwide. Ad5 vectors infect liver cells in vivo with high efficiency via a poorly defined mechanism, which involves virus binding to vitamin K-dependent blood coagulation factors. Here, we report that the major Ad5 capsid protein, hexon, binds human coagulation factor X (FX) with an affinity of 229 pM. This affinity is 40-fold stronger than the reported affinity of Ad5 fiber for the cellular receptor coxsackievirus and adenovirus receptor, CAR. Cryoelectron microscopy and single-particle image reconstruction revealed that the FX attachment site is localized to the central depression at the top of the hexon trimer. Hexon-mutated virus bearing a large insertion in hexon showed markedly reduced FX binding in vitro and failed to deliver a transgene to hepatocytes in vivo. This study describes the mechanism of FX binding to Ad5 and demonstrates the critical role of hexon for virus infection of hepatocytes in vivo.

State of the art on autologous mesothelial transplant in animals and humans.

Sixteen years ago rabbit and human mesothelial cells were successfully cultured and autoimplanted. The aim of the study was merely to demonstrate that mesothelial implant was possible and interesting not only in peritoneal dialysis, but also in the vaster field of medicine and surgery concerning all the mesothelial districts of the body. The aim of this paper is to recollect the steps which have led to autologous mesothelial transplantation and verify if the technique has been validated and adopted by others. Review of the literature published in the last 15 years shows that intraperitoneal transplantation of mesothelial cells has been effective in reducing the formation of peritoneal adhesions, and in remodeling the area of mesothelial denudation. New studies on the mesothelial cell opened the way to construction of transplantable tissue-engineered artificial peritoneum, to the utilization of mesothelial progenitor cells and to find simple methods to collect autologous mesothelial cells. Finally mesothelial transplantation may represent a new neovascular therapy in the prevention and treatment of ischemic coronary heart disease.

Possible role of milky spots in mesothelial transplantation.

Milky spots are very small omental organs, in contact with peritoneal membrane, devoid of capsule and consisting of macrophages, lymphocytes and a few plasma cells supported by blood and lymphatic vessels. The exact role of these particular organs is still not clear, but they are similar to lymphatic structures and it is clear that they play a role in peritoneal infection and abdominal tumors. Peritoneal dialysis seems to activate the milky spots changing their morphology. The authors try to formulate some hypotheses on the role played by these little omental organs during autologous mesothelial transplant.

Evaluation of exercise testing for subjects with isolated proteinuria and/or hematuria of unclear significance.

BACKGROUND: A frequent problem that family doctors face is the meaning of small quantities of blood or protein in urine samples. Patients with this problem are often either neglected or referred to specialists for complex, expensive, and often invasive diagnostic procedures. Exercise testing has never been considered in nephrology, except for some attempts in diabetic patients. METHODS: We report on a study conducted over 12 years with patients referred for slight hematuria and/or proteinuria to determine whether exercise testing could be a diagnostic aid in some or all of them. We performed exercise testing using a treadmill preceded and followed by urine analysis, with a kidney biopsy within 10 days. Of the 94 patients enrolled in the study, only those with a positive exercise test turned out to have parenchymal nephropathy. At the end of the study, we simplified the quantification of exertion, dispensing with the treadmill and drastically reducing the number of urinary parameters considered. RESULTS: In patients with histological evidence of kidney damage, most of the variables increased significantly after the test. Statistical analysis also showed that determination of proteinuria and hematuria alone guaranteed maximum predictability. We found that it is also possible to simplify the quantification of effort/exertion and to drastically reduce the number of urinary parameters and still obtain significant results. CONCLUSIONS: Exercise testing provides useful information about the significance of microhematuria and proteinuria, reducing the number of cases that need to be referred to specialists. The method needs to be validated in other studies, but our results suggest that family doctors could use simple dipsticks to screen the many cases of microhematuria or proteinuria observed in daily practice. The method seems useful in eliminating doubts and unnecessary diagnostic costs.

High doses of water increase the purifying capacity of the kidneys.

BACKGROUND: In previous studies we were successful in demonstrating that the administration of water over a short period of time increases the transport capacity in the excretory tract of rabbit ureters by increasing urinary volume in the ureter from 0.3 ml/min to 10 ml/min. This phenomenon may explain the effect of water therapy performed in thermal spas, where the administration of 1-2 liters of mineral water is performed in 30-60 minutes. OBJECTIVES: The aim of the present study is to investigate if this increased transport capacity can act also in the renal tubular apparatus to modify the excretion of some endogenous substances. MATERIALS AND METHODS: We evaluated daily renal clearances in ten subjects under basal conditions during supplemental administration of 25 ml/kg of mineral water over a 24-hour period and during the administration of the same amount of water over a 30-minute period. RESULTS: Subjects who drank a water load of 25 ml/Kg over 30 minutes showed a higher diuresis than that observed in those who drank the same amount over a 24-hour period. Creatinine and urea clearance at 24 hours were significantly higher in subjects who drank the water load over 30 minutes. Serum magnesium levels and folic acid levels were also significantly higher in subjects who drank the water load over 30 minutes. CONCLUSIONS: Water administration over a short period of time seems to modify the daily excretion of some endogenous metabolites.

Evaluation of adenovirus vectors containing serotype 35 fibers for tumor targeting.

There is growing evidence from in vitro studies that subgroup B adenoviruses (Ad) can overcome the limitations in safety and tumor transduction efficiency seen with commonly used subgroup C serotype 5-based vectors. In this study, we confirm that the expression level of the B-group Ad receptor, CD46, correlates with the grade of malignancy of cervical cancer in situ. We also demonstrate the in vivo properties of Ad5-based vectors that contain the B-group Ad serotype 35 fiber (Ad5/35) in transgenic mice that express CD46 in a pattern and at a level similar to humans. Upon intravenous and intraperitoneal injection, an Ad5/35 vector did not efficiently transduce normal tissue, but was able to target metastatic or intraperitoneal tumors that express CD46 at levels comparable to human tumors. When an oncolytic Ad5/35-based vector was employed, in both tumor models antitumor effects were observed. Furthermore, injection of Ad5/35 vectors into CD46 transgenic mice caused less innate toxicity than Ad5 vectors. Our data demonstrate that Ad vectors that target CD46 offer advantages over Ad5-based vectors for treatment of cancer.

The self-locating catheter: review and cost analysis.

The self-locating catheter invented by Nicola Di Paolo has been increasingly used in Italy and elsewhere since 1994, with about a thousand patients currently implanted every year. Twelve grams of tungsten inserted in the tip of the conventional Tenckhoff catheter during extrusion do not significantly change its form, but suffice to keep the tip firmly in the Douglas cavity. The validity of the new catheter is confirmed by a multicentric controlled study in a large population of peritoneal dialysis patients. This trial showed that patients with the new catheter have fewer episodes of peritonitis, tunnel infection, cuff extrusion, catheter malfunction, obstruction and leakage. This paper outlines the present situation and reports a comparative analysis of the costs of Tenckhoff and self-locating catheters.

Extracorporeal blood oxygenation and ozonation (EBOO): a controlled trial in patients with peripheral artery disease.

BACKGROUND: Since 1990 our group has been using extracorporeal circulation to ozonate blood by an original method, known as extracorporeal blood oxygenation and ozonation (EBOO), with the aim of amplifying the results observed with ozone autohemotherapy. OBJECTIVE: To verify the hypothesis that EBOO improves the skin lesions typical of peripheral artery disease (PAD) patients. METHODS: Twenty-eight patients with PAD were randomized to receive EBOO or intravenous prostacyclin in a controlled clinical trial. The primary efficacy parameters were regression of skin lesions and pain,and improvement in quality of life and vascularisation. RESULTS: Patients treated with EBOO showed highly significant regression of skin lesions with respect to patients treated with prostacyclin. Other parameters that were significantly different in the two groups of patients were pain,pruritus, heavy legs and well-being. No significant differences in vascularisation of the lower limbs before and after treatment were found in either group. No side effects or complications were recorded during the 210 EBOO treatments. CONCLUSION: EBOO was much more effective than prostacyclin for treating skin lesions in PAD patients and also had a positive effect on patient general condition without any apparent change in arterial circulation. This suggests other mechanisms of action of EBOO.

Extracorporeal blood oxygenation and ozonation: clinical and biological implications of ozone therapy.

Some lines of evidence have suggested that the challenge to antioxidants and biomolecules provoked by pro-oxidants such as ozone may be used to generate a controlled stress response of possible therapeutic relevance in some immune dysfunctions and chronic, degenerative conditions. Immune and endothelial cells have been proposed to be elective targets of the positive molecular effects of ozone and its derived species formed during blood ozonation. On the bases of these underlying principles and against often prejudicial scepticism and concerns about its toxicity, ozone has been used in autohemotherapy (AHT) for four decades with encouraging results. However, clinical application and validation of AHT have been so far largely insufficient. Latterly, a new and more effective therapeutic approach to ozone therapy has been established, namely extracorporeal blood oxygenation and ozonation (EBOO). This technique, first tested in vitro and then in vivo in sheep and humans (more than 1200 treatments performed in 82 patients), is performed with a high-efficiency apparatus that makes it possible to treat with a mixture of oxygen-ozone (0.5-1 microg/ml oxygen) in 1 h of extracorporeal circulation up to 4800 ml of heparinized blood without technical or clinical problems, whereas only 250 ml of blood can be treated with ozone by AHT. The EBOO technique can be easily adapted for use in hemodialysis also. The standard therapeutic cycle lasts for 7 weeks in which 14 treatment sessions of 1 h are performed. After a session of EBOO, the interaction of ozone with blood components results in 4-5-fold increased levels of thiobarbituric acid reactants and a proportional decrease in plasma protein thiols without any appreciable erythrocyte haemolysis. On the basis of preliminary in vitro evidence, these simple laboratory parameters may represent a useful complement in the routine monitoring of biological compliance to the treatment. The clinical experience gained so far confirms the great therapeutic potential of EBOO in patients with severe peripheral arterial disease, coronary disease, cholesterol embolism, severe dyslipidemia, Madelung disease, and sudden deafness of vascular origin. Extensive investigation on oxidative stress biomarkers and clinical trials are under way to validate this new technique further.

Experimental evaluation of transport force in the rabbit ureter.

BACKGROUND: Cleaning the urinary tract by so-called 'wash-out effect' and promoting high diuresis has long been advocated but has had very little scientific backing and few prospective studies in international journals. AIM: To verify whether the physical laws describing the transport force of water in rivers and pipes are also valid for urinary outflow. METHODS: A laboratory model for measuring transport force, given liquid and solid capacity, was adapted to create an in vivo model based on the rabbit urinary tract. RESULTS: Fluid flow in the rabbit renal pelvis and ureters was found similar to flow in pipes, obeying the physical laws of water transport to some extent. When the quantity of liquid flowing in the urinary tract in unit time was doubled, the transport force increased by various orders of magnitude. When the liquid increased by a larger factor, the transport force became enormous. CONCLUSIONS: The results confirm the utility of maintaining high diuresis in patients with renal calculus, but stress the utility of drinking 1-2 liters of hypotonic water in a short time to obtain an enormous increase in transport force which increases the probability of a cleansing effect.

A mathematical approach to the evaluation of sediment transport capacity in the human urinary tract.

BACKGROUND: It is not yet clear whether forced diuresis is useful for flushing out of the urinary tract, especially in cases of renal calculi or infections. A series of experiments conducted initially in vitro and then in vivo in rabbits, using sand and small glass spheres, showed that sediments can be eliminated from the urinary tract by forced diuresis. When distilled water was used, the effect was greater, both as weight of sand and as number of spheres eliminated, than when normal saline was used. The different characteristics of the two liquids gave rise to different intrapelvic pressures for a given flow. MATERIALS AND METHODS: Intrapelvic pressures, and liquid and solid discharges in vitro and in rabbits were used in a fluid mechanics analysis of the phenomenon to obtain non-dimensional formulae so that the results in rabbits could be extended to humans. RESULTS: The results made it possible to evaluate solid transport capacity induced in a healthy human of given weight by drinking a given quantity of water in an hour. CONCLUSIONS: The mathematical model makes it possible to determine the quantity of water a patient must drink to induce a transport force sufficient for urinary tract wash-out.

Theoretical morphological approach to simple peritoneal sclerosis.

The term peritoneal sclerosis can be applied to a vast range of peritoneal alterations. At one end of the range we have the slight peritoneal sclerosis constantly associated with peritoneal dialysis, which may be defined as simple sclerosis. Its clinical impact is slight. The role of glucose in determining peritoneal sclerosis is supported by morphological studies and therefore backed by much biochemical and immunological data.

Simple peritoneal sclerosis and sclerosing peritonitis: related or distinct entities?

AIM: The etiopathogenesis of sclerosing peritonitis is still debated, with some sustaining that it is a rare form of progression of simple peritoneal sclerosis and others that it is a primitive form. The aim of the present research was to clarify this question. MATERIAL AND METHODS: 438 peritoneal biopsies from 253 patients were re-examined. 174 were obtained prior to peritoneal dialysis and 224 after various periods of dialysis. Forty biopsies were from peritoneal dialysis patients who developed sclerosing peritonitis. Peritoneal morphology was studied for signs of transition from simple sclerosis to sclerosing peritonitis. RESULTS: Evidence was found sustaining the hypothesis that simple sclerosis to sclerosing peritonitis patients have distinct pathologies. CONCLUSIONS: The results confirm previous observations, excluding the existence of any type of relation between simple peritoneal sclerosis to sclerosing peritonitis.

Prevention of peritoneal sclerosis: a new proposal to substitute glucose with carnitine dialysis solution (biocompatibility testing in vitro and in rabbits).

AIM: Commercial glucose peritoneal dialysis solutions expose the peritoneum to hyperosmolar glucose containing variable amounts of non-enzymic breakdown products of glucose. These solutions are toxic for the peritoneum. The aim of the present study is to compare in vitro and in vivo characteristics of a new dialysis solution containing carnitine, a naturally occurring compound, as substitute of glucose. MATERIAL AND METHODS: We compared in vitro and in the rabbit a new peritoneal dialysis solution containing carnitine, with two standard bicarbonate glucose peritoneal dialysis solutions and a solution containing icodextrin. RESULTS: In vitro and in vivo the solution containing carnitine seems to be more biocompatible than standard glucose solutions and those containing icodextrin. CONCLUSIONS: In our study the peritoneal dialysis solution containing carnitine seems to prevent the mesothelial changes observed with solutions containing glucose. Since carnitine has been extensively studied and seems to be well tolerated by hemodialysis patients, even at high doses for long periods, clinical trials in humans may be planned in the near future.

Accidental death due to erroneous intravenous infusion of hypertonic saline solution for hemodialysis.

The case of a continuous hemodialysis patient who died shortly after erroneous infusion with undiluted hypertonic solution is reported. Autopsy showed small parenchymal hemorrhages in all organs. Although producers take measures to prevent such errors by hospital staff, further steps are suggested for types of dialysis requiring reinfusion of large quantities of reinfusion hemodialysis solution.