Acute Appendicitis During Coronavirus Disease 2019 (COVID-19): Increasing Incidence of Complicate Appendicitis, Severity and Length of Hospitalization.

BACKGROUND/AIM: COVID-19 is rapidly spreading, and due to the high morbidity and mortality caused by the pandemic many Governments have introduced social restrictions. Those measures combined with infection-related patient anxiety, led to hiding other diseases. The aim of this study was to evaluate the impact of COVID-19 on numbers and severity of acute appendicitis cases referred during the pandemic. PATIENTS AND METHODS: Between March 2019 and March 2021, all patients who underwent appendectomy in Tor Vergata Hospital, Rome were included. Patients were divided in two groups (COVID-19/pre-COVID-19). Clinical features, intraoperative findings, hospital stay, and histologic examination data were included in the retrospective analysis. RESULTS: Out of 334 admitted patients, 36 (10.7%) had a diagnosis of acute appendicitis (COVID-19 group) vs. 59(11.2%) in the pre-COVID-19 group. The COVID-19 group presented significantly longer hospitalization, incidence of appendicular abscess, perforation, and severity of inflammation at univariate analysis p=0.002, p=0.021, p=0.001, p=0.006, p=0.001, respectively. At multivariate analysis, appendicular abscess (p=0.015) and higher serum levels of C reactive protein (p<0.008) were associated with prolonged hospital stay. CONCLUSION: This study highlights the correlation between COVID-19 pandemic and the severity of acute appendicitis presentations.

The treatment of acute appendicitis in two age-based groups during COVID-19 pandemic: a retrospective experience in a COVID-19 referral hospital.

PURPOSE: During the past months, the Italian Government has reduced the restrictions and access to hospitals as well as outpatient. Since then, up to 40% of non-traumatic abdominal emergencies have had unusual delayed treatment. Given the rapidly evolving situation and the absence of evidence to support recommendations during the COVID-19 pandemic, it is useful to assess how the current situation is influencing the management of elderly patients with acute appendicitis. METHODS: Between February 2020 and December 2020, all patients 18 years or older undergone appendectomy were included. Patients were divided in two age-based groups (young groups, YG; elderly group, EG). Surgical approach, hospital stay, post-operative complications, radiology reports, and histologic examination were included in the retrospective analysis. RESULTS: One hundred eight patients underwent appendectomy, 81 patients into the YG, and 27 in the EG. Laparoscopy was performed in 87.7% of the YG and in 51.8% of the elderly (p < 0.000), while conversion to laparotomy was necessary in 3.7% in the YG vs 22.3% of the other group (p < 0.009). Open procedures were more frequent in the EG, 25.9% vs 8.6% (p value < 0.05). No mortality rate was reported in both groups; moreover, the mean hospital stay was greater in the EG than the YG (p < 0.000). CONCLUSION: Our data highlighted a partial delay in diagnosis in the elderly group, and an increase in complicated appendicitis also demonstrated by the need for conversion to laparotomy despite no significant relationship between these findings and the histologic examination was reported.

A Rare Case of Xanthogranulomatous Pyelonephritis with Spontaneous Renocolic Fistula and IVC Thrombosis.

Xanthogranulomatous pyelonephritis (XGPN) is a rare disorder affecting the kidney which can fistulise to the colon in exceptional cases. We herein report a case of XGPN with renocolic fistula and large vessel thrombosis presenting with sepsis and pulmonary embolism. Preoperative diagnosis and strategic planning resulted in successful management. A 64-year-old woman presented to the emergency department with abdominal pain and a septic condition, corroborated by venous thromboembolism. Workup diagnosed a left renal abscess with calicocolic fistula. Scintigraphy confirmed a nonfunctioning left kidney. The patient underwent inferior vena cava filter placement and staged surgery. The first, damage control procedure was a loop ileostomy. Ten days later, when the patient's conditions improved, she underwent left nephrectomy and left colectomy with primary anastomosis. Finally, a year later, the ileostomy was closed. At follow-up, the patient was well, with unremarkable renal function. Scrupulous diagnostics, multidisciplinary decision making, and staged intervention have been key to optimal outcome.

Ileal Neuroendocrine Tumor in a Patient with Sclerosing Mesenteritis: Which Came First?

BACKGROUND Jejunoileal neuroendocrine tumors (JI-NETs) are rare tumors that can be associated with mesenteric fibrosis. This case report is of an incidental finding of a JI-NET in a patient who was previously misdiagnosed with sclerosing mesenteritis. CASE REPORT A 42-year-old man was admitted to our institution with diffuse abdominal pain and clinical and radiographic signs of bowel obstruction. He had a previous diagnosis of sclerosing mesenteritis, which had been histologically diagnosed after an exploratory laparoscopy performed in 2009 for recurrent acute abdominal pain. He was also annually monitored through computed tomography scans for an incidentally discovered, gradually enlarging mesenteric mass for which a "wait and watch" management approach was adopted. After a period of fasting and observation, the patient underwent an urgent exploratory laparotomy because of his worsening condition. Intraoperatively, an ileocecal resection was performed, along with excision of the known mesenteric mass. The pathology report revealed an ileal NET with nodal metastases within the mesentery and mesenteric tumor deposits (pT3N1). CONCLUSIONS JI-NETs are rare entities, which are usually encountered as incidental findings or in patients with unspecific abdominal pain. Our case represents a probable delayed diagnosis of JI-NET in the context of sclerosing mesenteritis; therefore, a possible association between these 2 conditions should be investigated.

Radiofrequency hemorrhoidectomy: less is less? Results of a comparative study.

BACKGROUND: Radiofrequency has been introduced as an instrument conceived to upgrade the conventional treatment of hemorrhoidectomy. To reduce the economic aspect, recently a new radiofrequency device has been introduced: Vojant™. The aim of this study was to compare the clinical outcomes of hemorrhoidectomy with LigaSure™ and Vojant™, performed with the Milligan-Morgan technique, on the medium term. METHODS: Between January 2016 and December 2016, 50 consecutive patients with symptomatic grade III and IV were scheduled for surgical treatment. Patients were assigned randomly to either Vojant™ or LigaSure™ hemorrhoidectomy. All preoperative and postoperative data were collected. RESULTS: Patients in the LigaSure™ group experienced less pain than those treated with Vojant™, (P<0.05). In the Vojant™ group one patient developed immediate postoperative bleeding (within 48 hours), the other one seven days after surgery. Complete wound healing and return to work activities was faster in the LigaSure™ group (P<0.05). One case of stenosis in the LigaSure™ group and two in the Vojant™ group were detected (P>0.05). CONCLUSIONS: Radiofrequency hemorrhoidectomy with Vojant™ seems a valid alternative to LigaSure hemorrhoidectomy.

Endoluminal Vacuum Therapy as Treatment for Anastomotic Colorectal Leakage.

BACKGROUND: The clinical leakage rate after anterior resection varies from 2.8-20%, with a 6-22% mortality rate and a 10-80% risk of permanent stoma. Endo-SPONGE® (B. Braun Melsungen AG, Melsungen, Germany) may treat extraperitoneal anastomotic leakage in the lesser pelvis. It consists of an open-pored sponge inserted into the cavity. A drainage tube fixed to a low vacuum drainage system is then connected to the sponge through the anus. MATERIAL AND METHODS: Between January 2007 and December 2014, 14 patients with anastomotic leakage following low anterior resection were treated with Endo-SPONGE® and were prospectively evaluated. In all patients, a CT-scan was performed and they received an intravenous antibiotic therapy with piperacillin+tazobactam (4.5g,3 times/daily). Complete healing was defined as endoscopically proven closure of the insufficiency cavity with a normal mucosa. RESULTS: Stapled straight end to end, colorectal anastomoses were performed in all patients between 3-7 cm above the anal verge, a protective loop ileostomy was performed in every patient. The diagnosis of anastomotic leakage was performed after a median interval of 14 days, the median size of the cavity was 81x46 mm. Fluid collection was drained, percutaneosly in 12 cases, surgically in two patients. The median duration of therapy was 35 days, with 3-14 sponge exchanges for each patient. Median healing time was 37 days. No intraoperative complications were recorded, however, we found five cases of mild anal pain treated medically. CONCLUSION: Considering the literature and our results, the Endo-SPONGE® seems an effective, minimally invasive procedure to treat extraperitoneal anastomotic leakage, reducing morbidity, mortality, and hospital stay.

Laparoscopic Treatment of Giant Ventral Hernia: Experience of 35 Patients.

BACKGROUND: Minimal access surgery for incisional hernia repair is still debated, especially for giant wall defects. Laparoscopic repair may reduce pain and hospital stay. This study was designed to evaluate the feasibility of the laparoscopic technique in giant hernia. MATERIALS AND METHODS: From 2007 to 2013, 35 consecutive patients with giant ventral hernia, according to the Chevrel classification, underwent laparoscopic repair. Fourteen patients were obese, with a body mass index (BMI) > 30 and in 21 patients the mean BMI was 24 (range 22-28). In all patients, the wall defect was larger than 20 cm. RESULTS: Mean operative time was 159±30 minutes, and, for defects larger than 25 cm, it was 210±20 minutes. Patient conversion did not occur. In 29 patients, the mean wall defect was 20x25 cm, and in six patients the mean wall defect was 26x31 cm, and, as measured from within the peritoneal cavity, the mean overlap was 5 cm (range 3-6). Short-term antibiotic prophylaxis consisted of Cefazolin 2 g IV (intravenous) the day of surgery. All patients were discharged within 72-96 hrs. The mean follow-up was 24 months. No infection occurred and no chronic pain was recorded. However, three seroma were observed (outpatient treatment) and two xiphoid recurrences were observed. CONCLUSIONS: Laparoscopic hernia repair is technically feasible and is safe in patients with giant fascial defects as well as obese patients. This operation decreases postoperative pain, hastens the recovery period, and reduces postoperative morbidity and recurrence. This approach should be reserved for patients with no history of previous hernia repair. Further studies are expected to confirm these promising results.

May radiofrequency be the best choice for III-IV degree hemorrhoids?

BACKGROUND: Hemorrhoidectomy is considered the most efficient method to treat hemorrhoids of III and IV grades. The aim of this study was to compare conventional diathermy hemorrhoidectomy and radiofrequency hemorrhoidectomy based on a large series of patients. METHODS: Between June 2001 and June 2014, 1000 patients have been treated with radiofrequency hemorrhoidectomy (group A) and 500 patients have been treated with diathermy (group B) as a day-case procedure. Operating time, postoperative pain score, hospital stay, early and late postoperative complications, wound healing time and time to return to normal activities were assessed. RESULTS: The mean follow-up was seven years. The mean operating time for radiofrequency hemorrhoidectomy was shorter than diathermy but not significantly. Patients treated with radiofrequency had significantly less postoperative pain (measured on a Visual Analogue Scale; P=0.001), a shorter wound healing time, less time off work and postoperative complications (P=0.001) than patients who had diathermy. Neither wound healing nor mean hospital stay (day-case surgery) was significantly different. CONCLUSIONS: Radiofrequency hemorrhoidectomyis a valid alternative to the conventional diathermy technique, due to the reduction of operative time, postoperative pain, early and late complication rate.

LigasureTM hemorrhoidectomy: how we do.

BACKGROUND: Hemorrhoidectomy is considered the gold standard and the most effective and definitive treatment for grades 3 or 4 hemorrhoids, and Milligan-Morgan's and Ferguson's procedures are the most widely used techniques throughout the world. The aim of the study was to present our surgical technique using LigasureTM vessel sealing, focus on technical aspects and surgical tricks showing our results with a huge number of patients and a long-term follow-up. METHODS: Between June 2001 and June 2014 at the University Hospital of Tor Vergata, Rome, Italy, 1000 patients were selected to underwent LigasureTM hemorrhoidectomy for III and IV degree hemorrhoids. Age range 19-80 years, ASA I-II-III. Operating time, postoperative pain score, hospital stay, early and late postoperative complications, wound healing time and time to return to normal activities were assessed. Patients were followed-up at one week, one month, six, and twelve months after the operation and after 60 months they responded to the follow-up telephone interview and replied to the questionnaire. RESULTS: One-thousand patients were undergone LigasureTM hemorrhoidectomy. The mean follow-up was 7 years and 110 (11%) patients was lost from the follow-up after the first postoperative month. Among early postoperative complications, 21 patients (2.1%) has urinary retention treated with a urinary catheter and removed before the discharge. 3 (0.3%) patients had a minor bleeding that required a package of hemostatic absorbable sponge, as late complications, in 35 patients (4%) anal fissure due to hard stool, an incomplete healing was observed in 11 patients (1.1%) after the first month. Three transphincteric anal fistulas (0.3%) were collected and four perianal abscess (0.4%) were observed during the first month of the follow-up and they required a delayed surgical treatment. At the end of the seven years of follow-up 70 recurrences (7.8%) and 35 anal stenosis (4%) were detected. CONCLUSIONS: If technical guidelines are respected rigorously and the device is applied correctly, feared late complications, such as impaired fecal continence, anal stricture and postoperative pain can be minimized.

Does a relationship still exist between gastroesophageal reflux and Helicobacter pylori in patients with reflux symptoms?

BACKGROUND: The nature of the relationship between Helicobacter pylori and reflux esophagitis (RE) is not fully understood. In addition, the effect of H. pylori eradication on RE and gastroesophageal reflux disease (GERD) is unclear. This study was designed to investigate the relationship between H. pylori infection and the grade of GERD in patients with reflux symptoms. METHODS: Between January 2010 and July 2013, 184 consecutive patients with daily reflux symptoms for at least one year were evaluated at the ambulatory for functional esophageal disease, Tor Vergata University Hospital, Rome, Italy. All patients underwent a pretreatment evaluation, which included anamnesis, clinical examination, Esophagogastroduodenoscopy (EGDS) with biopsy, esophageal manometry and 24-hour pH-metry. All statistical elaborations were obtained using Statigraphies 5 plus for Window XP. RESULTS: There was no statistical difference regarding Lower Esophageal Sphincter (LES) pressure between patients who were H. pylori-positive and H. Pylori-negative (19.2 ± 9.5 (range: 3.7 to 46.2) and 19.7 ± 11.0 (range: 2.6 to 61), respectively). Further, no significant difference was evidenced in esophageal wave length (mean value: 3.1 seconds in H. pylori-negative patients versus 3.2 seconds in H. pylori-positive patients) or in esophageal wave height (mean value: 72.2 ± 39.3 in H. pylori-negative patients versus 67.7 ± 28.4 in H. pylori-positive patients). We observed that hiatal hernia (P = 0.01), LES opening (P = 0.05), esophageal wave length (P = 0.01) and pathological reflux number (P = 0.05) were significantly related to the presence of esophagitis. However, H. pylori infection was not significantly related to the presence of reflux esophagitis. CONCLUSIONS: Our clinical, endoscopic, manometric and pH-metric data shows no significant role of H. pylori infection in the development of GERD or in the pathogenesis of reflux esophagitis. However, current data do not provide sufficient evidence to define this relationship and further prospective large studies are needed.

Local food and cardioprotection: the role of phytochemicals.

For decades, most of the attention of nutritionists and health professionals has focused on the impact of the major dietary components, such as the amounts and types of fats, proteins, carbohydrates and fibers, on human health. However, interest in the role of minor components is rapidly growing. Many constituents of plants are non-nutritional compounds that play key roles in plant physiology and interactions with the environment. Over the past few years, we performed human studies to ascertain the health effects of Mediterranean foods such as extra virgin olive oil and tomatoes. Recently, we became interested in endothelial dysfunction and its implications in aging. To study the effects of local food plants on vascular function, plants were collected in Southern Italy. Extracts were first tested for their antioxidant activity in a variety of assays. The effects on the production of vasorelaxant factors were then investigated in cell culture. Finally, aged rats were fed with a wild artichoke extract and their vasomotion responsiveness was evaluated. In synthesis, the data uniformly demonstrate that phytochemical components of the Mediterranean diet exert cardioprotective effects whose mechanisms are being progressively elucidated.

Effect of a tomato-based drink on markers of inflammation, immunomodulation, and oxidative stress.

Regular consumption of tomato and its products is being consistently associated with lower risk of several types of cancer and, to a lesser extent, coronary heart disease. Among the many tomato components credited with healthful properties, carotenoids and particularly lycopene are being actively investigated. Given the recognized role of immune/inflammatory processes in atherogenesis, the effects of a tomato-based drink (Lyc-o-Mato), which was previously shown to afford DNA protection from oxidative stress, on the modulation of immune and inflammatory markers (by enzyme immunoessay), on basal lymphocyte DNA damage (by comet assay), and on F2-isoprostane excretion (by LC-MS/MS), were investigated in 26 healthy young volunteers. In a placebo-controlled, double-blind, crossover study, Lyc-o-Mato (5.7 mg of lycopene, 3.7 mg of phytoene, 2.7 mg of phytofluene, 1 mg of beta-carotene, and 1.8 mg of alpha-tocopherol) or a placebo drink (same taste and flavor, but devoid of active compounds) were given for 26 days, separated by a wash-out period. During the study subjects maintained their habitual, hence unrestricted, diet. TNF-alpha production by whole blood was 34.4% lower after 26 days of drink consumption, whereas the other parameters were not significantly modified by the treatment. In turn, modest effects of the regular intake of a tomato drink, providing small amounts of carotenoids, were found on the production of inflammatory mediators, such as TNF-alpha, in young healthy volunteers. Future intervention trials in subjects with low carotenoid status and/or compromised immune system will resolve the issue of whether carotenoids modulate immune parameters in humans.

Wild artichoke prevents the age-associated loss of vasomotor function.

Endothelial dysfunction, which is more often observed in conduit arteries such as the aorta, carotid, femoral, and brachial arteries, is largely due to alterations in cellular signal transduction initiated by an escalating cycle of damage triggered by oxidative stress. This phenomenon is exacerbated in the elderly, where a progressive loss of vascular endothelial function and concurrent loss of vasomotor control is frequent. In a previous study, we demonstrated that the wild artichoke (Cynara cardunculus) is able to increase the production of the vasorelaxant factor nitric oxide by cultured aortic endothelial cells. We now extended that study to verify (1) the vasorelaxant potential of C. cardunculus on isolated rat aortic rings and (2) whether the vasomodulating properties of C. cardunculus are maintained in vivo, after administration to aged rats. The results demonstrate that the wild artichoke and its main components, namely, luteolin and apigenin, improve aortic relaxation when added to the incubation bath. Moreover, the feeding of wild artichoke [10 mg (kg of polyphenols)(-1) day(-1)] to aged rats significantly restores proper vasomotion, to a degree similar to that observed in young animals. This study provides further justification to the advice to consume wild greens as part of a balanced diet and suggests that close attention should be paid to the diet of the elderly, because it can effectively modulate important parameters of cardiovascular risk.

Effects of blood orange juice intake on antioxidant bioavailability and on different markers related to oxidative stress.

Orange juice is a source of antioxidants that might afford in vivo protection from oxidative stress. To test this hypothesis, we carried out a human intervention study with blood orange juice containing high amounts of vitamin C, anthocyanins, and carotenoids. Sixteen healthy female volunteers were enrolled in a crossover study and were given 600 mL/day of blood orange juice or a diet without juice for 21 days. Before and after each intervention period, plasma vitamin C, cyanidin-3-glucoside, and carotenoids were quantified. Furthermore, plasma antioxidant capacity, malondialdehyde concentration in plasma, 11-dehydrotromboxane B(2) urinary excretion, and lymphocyte DNA damage were evaluated as biomarkers of oxidative stress. Blood orange juice consumption determined a significant increase in plasma vitamin C, cyanidin-3-glucoside, beta-cryptoxanthin, and zeaxanthin. Also, lymphocyte DNA resistance to oxidative stress was improved whereas no effect was observed on the other markers that we analyzed. In turn, these results suggest that blood orange juice is a bioavailable source of antioxidants, which might moderately improve the antioxidant defense system; however, the long-term effects of its consumption are to be further investigated.

Virgin Olive Oil Study (VOLOS): vasoprotective potential of extra virgin olive oil in mildly dyslipidemic patients.

BACKGROUND: In vitro, olive phenols exert potent antioxidant and enzyme-modulating activities. AIM OF THE STUDY: We comparatively evaluate, in mildly dyslipidemic patients, the vasoprotective potential of extra virgin olive oil. METHODS: 22 patients were administered 40 mL/day of either extra-virgin, i. e. phenol rich, or refined, i. e. phenol poor, olive oils (EVOO or ROO, respectively, with nearly identical fatty acid composition), with a crossover design. Each treatment was carried out for seven weeks, with four weeks of washout in between. Plasma antioxidant capacity, serum thromboxane B2 (TXB2) formation, and urinary isoprostane excretion were evaluated as surrogate markers of cardioprotective potential and vascular function. RESULTS: No effects on plasma lipid/lipoprotein profile were observed. Conversely, EVOO consumption was associated with favorable effects on circulating markers. Namely, decreased serum TXB2 production and increased plasma antioxidant capacity were observed when EVOO was administered in both treatment arms. Neither treatment had any significant effect on isoprostane excretion. CONCLUSIONS: EVOO consumption by mildly dyslipidemic patients is associated with favorable changes in circulating markers of cardiovascular condition. Based on current knowledge, these effects may be associated with cardioprotection.

Vasomodulating potential of mediterranean wild plant extracts.

The incidence of cardiovascular disease and endothelial dysfunction is low in the Mediterranean area, where the major proportion of daily calories comes from plant food, high in antioxidant polyphenols. It has been shown that a reduced production or enhanced inactivation of endothelium-derived nitric oxide (NO) is involved in the onset of endothelial dysfunction. We investigated the effects of Mediterranean wild plant, that is, wild artichoke and thyme, phenolic-rich extracts on NO release by porcine aortic endothelial cells (PAECs; by using indirect methods) and by cerebral cell membrane homogenates (by using direct NO detection). NO release by PAECs was significantly potentiated by 234% and 135% by wild artichoke and thyme extracts (10(-6) mol/L), respectively. Direct detection of NO release by brain membranes also showed significantly increased NO production after wild artichoke addition (+35.4%). Further, the release of another vasorelaxant factor by PAECs, that is, prostacyclin, was significantly increased by wild artichoke and thyme (10(-6) mol/L) (+269% and +190%, respectively). Investigation of the mechanism(s) of action of wild artichoke and thyme suggests maintenance of an intracellular reduced environment, as previously shown for ascorbate. Even though these data require in vivo confirmation, they suggest that regular intake of bioactive compounds from Mediterranean wild plants contributes to maintenance of proper vasomotion and to the low incidence of atherosclerosis and endothelial dysfunction recorded in the Mediterranean area.

Hypochlorous acid scavenging properties of local Mediterranean plant foods.

Oxidative modification of low density lipoprotein (LDL) is involved in the pathogenesis of atherosclerosis and coronary heart disease, which are low in the Mediterranean area possibly due to a high dietary proportion of plant foods. Ethanolic extracts were prepared from more than 120 Mediterranean edible plants collected in remote areas (which maintain their traditional diet) and their antioxidant potential was studied. Extracts derived from Agaricus campestris, Cynara cardunculus, Thymus pulegioides, and Vicia faba were subjected to further analysis in this study. The extracts' potential to scavenge the DPPH radical (2,2-diphenyl-1-picrylhydrazyl radical) and hypochlorous acid (HOCl), as well as their antioxidant capacity, was comparable to the those obtained for standard antioxidants (e.g., quercetin, Trolox). Myeloperoxidase (MPO) catalyzes the production of the highly chlorinating and oxidizing agent HOCl, which reacts with the LDL apoprotein moiety, leading to the derivatization of its aminoacidic residues. Coincubation with extracts significantly prevented HOCl-induced modification of the LDL residue tryptophan, whereas higher concentrations were required to retard lysine damage. Moreover, the extracts inhibited MPO-catalyzed guaiacol oxidation in a concentration-dependent manner in a cell-free assay but, in contrast, did not affect MPO activity in isolated human neutrophils. MPO is also known to facilitate nitric dioxide oxidation. The formation of 3-nitrotyrosine was significantly lower in bovine endothelial aortic cells incubated with C. cardunculus or T. pulegioides. In synthesis, our study shows that local Mediterranean plant foods prevent HOCl toxicity in vitro and, thus, suggests further mechanisms responsible for the reported health-beneficial effect of the Mediterranean diet.

Protective activity of tomato products on in vivo markers of lipid oxidation.

BACKGROUND: It has been suggested that regular consumption of tomato products improves antioxidant defenses due to their endogenous antioxidant compounds, notably lycopene. AIM OF THE STUDY: We evaluated the effects of tomato consumption on parameters of lipid oxidation in healthy human volunteers. METHODS: Twelve females (enrolled at T-7), after a one-week of carotenoid-poor diet (T0), were instructed to supplement the same diet with different tomato products (raw, sauce, and paste), thereby providing approximately eight mg lycopene/day for three weeks (T21). Blood samples were periodically collected in order to evaluate plasma carotenoid concentrations, plasma antioxidant capacity, and susceptibility of LDL to metal ion-induced oxidation. Furthermore, 8-iso-PGF(2alpha), a marker of in vivo oxidative stress, was analyzed in the 24-hour urine. RESULTS: Carotenoid concentrations decreased significantly during the carotenoid-poor diet (P < 0.05), while lycopene concentrations increased significantly after tomato consumption (P < 0.001). The antioxidant capacity of plasma did not vary during the study. Conversely, LDL oxidizability decreased after tomato consumption, as demonstrated by a shortening of the lag phase (P < 0.001). This parameter was significantly correlated with lycopene concentration (r = 0.36, P < 0.05). The excretion of 8-iso-PGF(2alpha) in urine was also significantly lower (-53%, P < 0.05 compared with T0) after tomato supplementation. CONCLUSIONS: These results further support a role for tomato products in the prevention of lipid peroxidation, a risk factor of atherosclerosis and cardiovascular disease.

Hydroxytyrosol excretion differs between rats and humans and depends on the vehicle of administration.

Interest in the in vivo biological activities of olive oil phenolics is rapidly growing, and different models and vehicles of administration are used worldwide. Matters of practicality determine the use of rats rather than humans as the model of choice. Also, growing interest in nutraceuticals is leading to the formulation of compounds containing olive oil phenols. In this study, we compared metabolism and urinary excretion of hydroxytyrosol [(HT), the most representative phenol of olive oil] between rats and humans by evaluating excretion of HT and its major metabolite, homovanillyl alcohol. Also, we compared human excretion of HT when consumed as a natural component of extra virgin olive oil, when added to refined olive oil, or when added to yogurt (as an approximation of functional food). Urinary excretion of HT was greater in humans than in rats, a species with a high basal excretion of HT and its metabolites. The high (234% of HT administered) excretion of free HT suggests that hydrolysis of oleuropein administered in humans (still an unresolved issue) occurs in vivo. Moreover, human HT excretion was much higher after its administration as a natural component of olive oil (44.2% of HT administered) than after its addition to refined olive oil (23% of HT administered) or yogurt (5.8% of dose or approximately 13% of that recorded after virgin olive oil intake). These data suggest that the rat is not the appropriate model for the study of HT metabolism and that HT-containing functional foods should be carefully formulated.