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Although the understanding of biochar stability in soil has improved in recent years, there is a lack of knowledge about how both the soil and biochar carbon (C) mineralisations are affected as a function of biochar amount applied to soil. Thus, increasing amounts of biochar were added to a Quartzipsamment in order to evaluate its priming effect on soil organic carbon (SOC) decomposition. We hypothesised that biochar will increase negative priming on native SOC mineralisation as function of its application rate to soil. The biochar was produced from sugarcane straw through slow pyrolysis at 450 °C, and a laboratory incubation was conducted for 90 days with the following treatments: soil-alone (C3 source), biochar-alone (C4 source) and soil with biochar at rates equivalent to 0.4% (T1), 0.8% (T2) and 1.9% (T3) (w/w). In the first day of incubation, biochar amendment reduced soil C mineralisation rates from 58 to 88% compared to the soil-alone as a function of increasing biochar application rates. This reduction was mainly attributed to the mineralisation of easily available substrates from incomplete pyrolysis, which were preferentially used by soil micro-organisms at early stages of incubation. This effect, however, subsided after 7 days of incubation and it was not sufficient to induce co-metabolism of SOC decomposition, which were 43% (T1)–71% (T3) lower compared to the control (soil-alone) after 90 days of incubation. This was reflected in the priming effect data, which confirmed the hypothesis that increasing application rates of biochar to soil induce stronger negative priming on SOM mineralisation. The predicted size of recalcitrant biochar C pool varied from 98.8% (T1) to 99.9% (T3) of the total biochar C with respective mean residence time of 454 and 1539 years. It was concluded that increasing rates of biochar application to soil induce stronger negative priming effect on SOC due to the higher proportional quantity of biochar labile C and preferential utilisation of this easily available C source by micro-organisms. However, the size and long residence time of the recalcitrant C pool of biochar confirm its stability in soil, thus being considered an opportunity for C sequestration in OC-poor soils. Additionally, this study draws encouraging perspectives on the evaluation of sugarcane straw as a chemical feedstock and an alternative biofuel through pyrolysis, providing appreciable amounts of a renewable product with a great potential for carbon storage.

To evaluate the natural history and outcome predictors in familial mesial temporal lobe epilepsy (FMTLE).

The aim of this paper was to evaluate the usefulness of coupling digital image analysis with immunohistochemistry and histomorphometry data to the study of tissue response to hydroxyapatite in a model of critical size bone defect in calvaria of rats. A transosseous defect measuring 8 mm in diameter was performed with a surgical trephine in the parietal bone of 40 rats and divided into two experimental groups according to the treatment: group I (blood clot, control), group II (HA) and killed 1, 3, 6 and 9 months after implantation (n=5/group/period). The skullcaps with overlaying skin were collected and processed for paraffin embedding. The specimens were cut in the laterolateral direction into 5-µm thick semi-serial sections and stained with hematoxylin-eosin for identification and counting of polymorphonuclears cells, mastocytes, and multinucleated giant cells, MNG, or immunolabeled with anti- lysozyme, -factor VIII and –PCNA. Digital images were obtained and analyzed with the ImagePro-Plus® software for cell couting (polymorphonuclears cells, mastocytes, macrophages and MNG) and microvessel density. Image segmentation of anti-PCNA immunostaining was used for cell proliferation analysis. The digital images obtained allowed clear identification of cells of interest by through morphological aspects or immunostaining. Data recording and analysis was facilitated by the use of specific software for image processing and graphical and statistical analysis. It can be concluded that the techniques applied were usefull to identify and count cells, structures and process of interest making easier the effectiveness of hydroxyapatite in the critical size defect in rat calvaria model.

A tunneled catheter is the alternative vascular access for those patients in need of hemodialysis who cannot undergo dialysis through an arterio-venous fistula or a vascular graft.This study was undertaken to evaluate the performance of the Ash Split Cath™, a 14 French chronic hemodialysis catheter with D-shaped lumens and a Dacron®cuff. After tunneling through a transcutaneous portion the catheter enters the venous system, where it splits into two separate limbs.Data regarding catheter positioning, function and adequacy of dialysis were collected from two hemodialysis facilities. Twenty-eight Ash-split catheters were placed in 28 patients, with no complications, and immediate technical success was 100%.Patients were followed up for a total of 7,286 catheter days. No catheter-related infections were observed. Only one catheter failed after 15 days, with a primary catheter patency of 96% for the whole study length. Mean blood flow was 303 ± 20 ml/min at 1 week after insertion, 306 ± 17 ml/min at 3 months, 299 ± 44 ml/min at 6 months, and 308 ± 16 ml/min at 12 months. With a mean dialysis session duration of 234 ± 25 minutes, adequate dialysis dose was observed for 96% of catheters, as reflected by a mean urea reduction ratio (URR) of 71%±8 or a mean urea kinetic modeling, or Kt/V, value of 1.51±0.3 during follow up. In conclusion, compared with previous studies we report the best permanent catheter performance, confirming that the Ash-split catheter is a good alternative for vascular access in hemodialysis patients who are not candidates for surgical A-V fistula or graft placement.

The levels of trans-resveratrol in 36 commercial red wines produced in the southern region of Brazil have been measured using a direct injection isocratic UV-HPLC method. The concentration of trans-resveratrol ranged from 0.82 to 5.75 mg/L with a mean value of 2.57 mg/L (R.S.D.%=1.99).

Radical-scavenging antioxidants, as part of the cellular defense system, function to inhibit the formation and propagation of free radicals and active oxygen species formation. In previous studies we demonstrated that endotoxin lipopolysaccharide (LPS) promotes oxidative stress and associated pathological changes in a rat model and that use of selected antioxidants was effective in reducing LPS-related lipid peroxidation product formation in the liver, as well as LPS-related pathological changes in different organs. In this study, several toxicological parameters (ie, clinical signs, blood chemistry, and histopathological changes) were compared among groups of male New Zealand rabbits injected with LPS following prophylactic pretreatment with either of 2 antioxidants, a group injected with LPS without pretreatment with antioxidants, groups injected with either of the 2 antioxidants only, and an untreated control group. The antioxidants used were a water-soluble natural antioxidant (NAO) from spinach and the NADPH oxidase inhibitor, apocynin. Exposure to LPS alone was associated clinically with depression, tachypnea, outer ear vasodilation, and iris congestion; biochemically with a significant increase in blood total bilirubin, transaminase activity, and glucose, total cholesterol, and triglyceride levels; macroscopically with multiple whitish areas in the liver; and histologically with hepatocellular focal necrosis and acute inflammation, thymic and splenic lymphoid necrosis and depletion, acute uveitis and hemorrhages in the ciliary processes, and decreased adrenal cortical cytoplasmic vacuolation considered consistent with depletion of steroidal hormone contents. The NAO had more effective prophylactic capacities than the apocynin. The protective effects were obvious in all investigated parameters. The results indicate the possible therapeutic efficacy of NAO in the treatment of clinical endotoxemia associated with gram-negative bacterial sepsis that is known to be associated with oxidative stress.

The aim of renal replacement therapy is to obtain blood purification from metabolic waste products sufficient to achieve patient rehabilitation, the control of dry body weight, and the correction of acid base and electrolyte imbalances (1–3).Among these, the correction of the hormonal imbalances as a result of renal disease would also be required (4). However, this is difficult to achieve, and the majority of substitute therapies such as hemodialysis and peritoneal dialysis focus on blood purification and fluid and electrolyte homeostasis.For this reason the search for the optimal dialytic therapy has been limited to the possibility of achieving a treatment that could at least be adequate in terms of blood purification and patient rehabilitation. Therefore, dialysis adequacy has been selected as a term to indicate successful renal replacement therapy, one that could overcome most of the uremic symptoms and allow the patient to reach a sufficient degree of rehabilitation, even though the treatment is far from the complete and optimal substitution of the lost kidney function in its whole.In recent years the concept of dialysis adequacy has been studied by several authors, and a continuous evolution of this concept has been observed. From the original description of the square-meter-hour hypothesis of Babb and Scribner in 1971 (5), a series of new studies led to the clinical application of various indices devoted to describing the level of efficiency achieved by dialysis treatment (6,7). Finally, after the American National Cooperative Dialysis Study was analyzed, and the KTNindex was selected as a marker for dialysis adequacy, the majority of authors now rely on this index and are proposing various formulas for its calculation (8–11).

Pathophysiology of peritoneal ultrafiltration is analyzed in the present study. Peritoneal equilibration test is the easiest procedure to study in detail the possible causes of failure to control the ultrafiltration rate in patients undergoing peritoneal dialysis. Membrane failure, reduction in peritoneal blood flow, excessive lymphatic reabsorption catheter malposition, and fluid sequestration are the most common causes of ultrafiltration loss. Pharmacologic manipulation of peritoneal membrane, correction of mechanical inconvenients, reduction in peritonitis rate and in the level of immunostimulation of the mesotelial macrophages, together with a careful policy in terms of glucose concentration in the dialysate and dwell times may contribute not only to treat different forms of ultrafiltration loss but also to prevent their incidence.

The toxicological evaluation of urinary human epidermal growth factor (u-hEGF) included mutagenicity, single and repeated dose general toxicity, and teratogenicity studies in various animal species. The mutagenic potential of u-hEGF was tested in vitro (Ames test, chromosome aberration in human lymphocytes, unscheduled DNA synthesis in HeLa cells) and in vivo (chromosome aberration in Chinese hamster bone marrow and micronucleus test in rat bone marrow). No mutagenic or clastogenic effects were found. The acute toxicity of u-hEGF was evaluated in mice and rats, using single subcutaneous (sc) or intravenous (iv) injection of 15 mg/kg. No toxic effects were observed. Four-week iv daily administration of u-hEGF at the doses of 0.3, 0.9, and 3 mg/kg in the SD rat followed by 2 wk of compound withdrawal induced pronounced and generally dose-related effects (i.e., epithelial hyperplasia) in a wide range of tissues and organs, at all doses. However, these effects were not apparently detrimental to the general health of the rats. The repeated sc administration of u-hEGF to cynomolgus monkeys for 4 wk at the same doses as used in the rat study resulted in lethality after about 7 days of treatment in the 2 higher dose groups or after 14 days at the lowest dose. The main clinical signs observed were gastrointestinal effects, respiratory distress, sedation, marked loss of body weight, and cutaneous desquamation. At histology, hyperplasia of most epithelia was seen in all groups. In addition, atrophy of the ovarian follicles and necrosis of the uterine endometrium were noted. Changes considered secondary to physical distress were atrophy of the hemopoietic and lymphatic system and hepatic steatosis. The embryofetal toxicity and teratogenicity of u-hEGF was tested, using the iv route in the SD rat and the iv and sc routes in the New Zealand White rabbit. In both species, the compound was administered at the doses of 0, 0.3, 0.9, and 3 mg/kg/day, from day 6 to 15 of pregnancy in rats and 6-18 in rabbits. In the rat, an increase in body weight was noted in the dams and fetuses at the 2 high doses. No embryotoxic or teratogenic effects were observed. In the rabbit studies, mortality and severe clinical signs involving various systems, with marked effects on the eyes, were observed at all doses tested during the first days of treatment by both routes. From the reproductive point of view, most of the surviving treated gravid females showed only resorptions.

Summary Scrapie infectivity is reduced 5–6 logs following filtration through 100,000 MW cut-off filter plus overnight treatment with 6 M urea. These steps, applied to purified human Growth Hormone (hGH), increase the margin of safety of hGH.

The histological, immunohistochemical, and electron microscopic characteristics of a spontaneous case of atriocaval mesothelioma are described in a 102-wk-old male Sprague-Dawley rat. The immunohistochemical characteristics of the tumor are compared with those of a pericardial mesothelioma in a female Sprague-Dawley rat.

A new blood module for continuous renal replacement therapies has been utilized to perform CVVH in critically ill patients. The features of the new module named (HP300 and manifactured by Medica srl (Medolla, Modena) are the easy installation and transportability to the bedside, the simple and safe management and the continuous measurement of the pre and post filter pressure with automatic calculation of the end-to-end pressure drop inside the filter. The last feature permits to detect early malfunctions of the filter due to fibers clotting or due to the internal coating of the hollow fibers by plasma proteins. In both cases the efficiency of the treatment can be reduced because of a significant reduction of the ultrafiltration rates or a remarkable decay of the membrane permeability and solute sieving coefficients. In many cases this reduction is only detected when important effects on solute removal have already occurred. In our experience, the new module permitted the substitution of the filters when early malfunctions were detected and maximal treatment efficiency was therefore guaranteed over extended periods of time.

Conglomerates of food and mucus or phytobezoars composed of vegetable matter are sometimes found in the stomach in the general population. Reports of phytobezoars in uremic patients are, however, scarce. Here we describe 2 uremic patients in which esophagogastroduodenoscopy was performed due to dyspepsia associated with weight loss and in which stomach phytobezoars were discovered. Theoretically, uremic patients should be at risk for producing bezoars. In fact, these patients frequently present predisposing conditions such as autonomic neuropathy, diabetes mellitus and delayed gastric emptying. Gastric bezoars cause anorexia. Anorexia is a frequent symptom in dialysis patients and is associated with malnutrition. In these patients, malnutrition is strongly associated with mortality and is quite difficult to reverse. Similarly, phytobezoars cause chronic anorexia. We suggest that clinicians working in dialysis units should consider the possibility of a gastric bezoar when evaluating anorexic uremic patients.

While reports of venous calcifications are scarce, vascular calcifications frequently occur in the arteries of uraemic patients. Venous calcification of an aged arterious-venous (a-v) fistula in a young patient with a long-standing history of hyperparathyroidism was detected on a forearm X-ray. Risk factors for vascular calcifications are still under debate, but calcium-phosphate product appears to be involved in its pathogenesis. We suggest that a-v fistula of patients with hyperparathyroidism history should be monitored as calcifications could be a risk factor for access thrombosis.

Nephrolithiasis is a rare finding in kidney transplantation and anuria could be the only clinical sign. We report the case of a 52-year-old Caucasian male renal transplant recipient admitted due to acute renal failure (ARF) and anuria. He reported no symptoms and a palpable bulge in the right iliac fossa corresponding to the graft was present. Ultrasonography showed hydronephrosis of the graft. A double-J ureteral stent was inserted with resolution of ARF. ARF with anuria and the presence of a palpable non-tender, elastic mass over the graft could be the clinical picture of obstructive ARF in a transplanted kidney.

Evaluation of the Toxicity of Indomethacin in a 4-Week Study, by Oral Route, in the Marmoset (Callithrix jacchus). OBERTO, G., CONZ, A., GIACHETTI, C., AND GALLI, C. L. (1990). Fundam. Appl Toxicol. 15, 800–813. A subacute toxicity study of Indomethacin administered by oral route, was carried out in the marmoset (Callithrix jacchus). Groups of three males and three females received Indomethacin directly into the stomach by means of a catheter for a period of 4 weeks at the dose levels of 0, 2, 6, and 12 mg/kg body wt/day and then were euthanized for pathological evaluation. All marmosets given 12 mg/kg/day and one marmoset given 6 mg/kg/day died during the dosing period (within 20 days). At 12 mg/kg/day, Indomethacin induced severe gastrointestinal toxicity (hemorrhage, ulcers, and necrosis with peritonitis), while at the dosages of 6 and 2 mg/kg/day some moderate to slight dose-related functional and morphological renal alterations (increase of serum urea, reduction of serum albumin, increase of serum potassium and/or chloride, and subacute inflammation) were observed. The fact that in many respects these alterations are similar to those observed in man is a further demonstration of the validity of the marmoset as an experimental model.

Paired filtration dialysis (two-chamber haemodiafiltration) was evaluated as a short, highly efficient renal replacement therapy in 35 uraemic subjects belonging to three different dialysis centres. The study period was 1 year. Patients were divided into two groups according to their body-weight and drinking habits. The smaller patients underwent 150-min dialysis sessions three times weekly. The larger patients underwent 3-h treatments thrice weekly. The treatment was adequate in all patients according to the KT/V criteria of adequacy. The intradialytic symptomatology was remarkably low and the treatments were well tolerated in all patients. The study confirms the reliability of aired filtration dialysis as a short dialysis technique. In some patients 150 min may be insufficient to achieve an equate dialysis efficiency and 180 min may be required for the majority of the population.