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Abnormal amyloid-β (Aβ) production and deposition is believed to represent one of the main causes of Alzheimer's disease (AD). γ-Secretase is the enzymatic complex responsible for Aβ generation from its precursor protein. Inhibition or modulation of γ-secretase represents an attractive therapeutic approach. CHF5074 is a new γ-secretase modulator that has been shown to inhibit brain plaque deposition and to attenuate memory deficit in adult AD transgenic mice after chronic treatment. To date, it is not known whether the positive behavioral effects of this compound also occur in young transgenic mice without plaque deposition. Here, we evaluated the effects of acute and subchronic treatment with CHF5074 on contextual and recognition memory and on hippocampal synaptic plasticity in plaque-free Tg2576 mice. We found that at 5 months of age, contextual memory impairment was significantly attenuated after acute subcutaneous administration of 30 mg/kg CHF5074. At 6 months of age, recognition memory impairment was fully reversed after a 4-week oral treatment in the diet (≈60 mg/kg/day). These cognitive effects were associated with a reversal of long-term potentiation (LTP) impairment in the hippocampus. A significant reduction in brain intraneuronal AβPP/Aβ levels and hyperphosphorylated tau, but no change in soluble or oligomeric Aβ levels was detected in Tg2576 mice showing functional recovery following CHF5074 treatment. We conclude that the beneficial effects of CHF5074 treatment in young transgenic mice occurred at a stage that precedes plaque formation and were associated with a reduction in intraneuronal AβPP/Aβ and hyperphosphorylated tau.

A growing number of laboratory and clinical studies over the past 10 years have shown that low-level laser stimulation (633 or 670 nm) at extremely low power densities (about 0.15 mW/cm(2)), when administered through a particular emission mode, is capable of eliciting significant biological effects. Studies on cell cultures and animal models as well as clinical trials give support to a novel therapeutic modality, which may be referred to as ultra low level laser therapy (ULLLT). In cultured neural cells, pulsed irradiation (670 nm, 0.45 mJ/cm(2)) has shown to stimulate NGF-induced neurite elongation and to protect cells against oxidative stress. In rats, anti-edema and anti-hyperalgesia effects following ULLL irradiation were found. Clinical studies have reported beneficial effects (also revealed through sonography) in the treatment of musculoskeletal disorders. The present paper reviews the existing experimental evidence available on ULLLT. Furthermore, the puzzling issue of the biophysical mechanisms that lie at the basis of the method is explored and some hypotheses are proposed. Besides presenting the state-of-the-art about this novel photobiostimulation therapy, the present paper aims to open up an interdisciplinary discussion and stimulate new research on this subject.

Introduction: The aim of this pilot study was to analyze the morphology of the cervical vertebrae of subjects with transverse maxillary constriction., Methods: The study population included 40 subjects (7-11 years of age) undergoing palatal expansion to correct transverse maxillary constriction, and a control group of 40 subjects (7-11 years of age) without transverse maxillary constriction. Two observers assessed cervical morphology on lateral cephalograms by means of templates showing cervical maturation sequences. Round angles and concave vertebral body edges were classified as vertebral anomalies that could not be associated with physiologic vertebral growth. Agreement between the data collected by the observers was assessed with the Cohen kappa test, and the data of the 2 groups were compared with the Fisher exact test (P <0.05)., Results: The 2 observers agreed in their assessments (k >0.5). The greater percentage of vertebral defects in the study group was significant (P <0.05) according to both observers. Rounding of the anterosuperior angle of the vertebral body was the most common defect in the study group. Vertebral defects of the study group were mainly at vertebrae C4 and C5., Conclusions: A statistically significant correlation, worthy of further study, was found between transverse maxillary constriction and cervical vertebral defects., (Copyright (c) 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Background: Considerable interest has been aroused in recent years by the well-known notion that biological systems are sensitive to visible light. With clinical applications of visible radiation in the far-red to near-infrared region of the spectrum in mind, we explored the effect of coherent red light irradiation with extremely low energy transfer on a neural cell line derived from rat pheochromocytoma. We focused on the effect of pulsed light laser irradiation vis-à-vis two distinct biological effects: neurite elongation under NGF stimulus on laminin-collagen substrate and cell viability during oxidative stress., Methods: We used a 670 nm laser, with extremely low peak power output (3 mW/cm2) and at an extremely low dose (0.45 mJ/cm2). Neurite elongation was measured over three days in culture. The effect of coherent red light irradiation on cell reaction to oxidative stress was evaluated through live-recording of mitochondria membrane potential (MMP) using JC1 vital dye and laser-confocal microscopy, in the absence (photo bleaching) and in the presence (oxidative stress) of H2O2, and by means of the MTT cell viability assay., Results: We found that laser irradiation stimulates NGF-induced neurite elongation on a laminin-collagen coated substrate and protects PC12 cells against oxidative stress., Conclusion: These data suggest that red light radiation protects the viability of cell culture in case of oxidative stress, as indicated by MMP measurement and MTT assay. It also stimulates neurite outgrowth, and this effect could also have positive implications for axonal protection.

The skin is a neuroendocrine immune organ in which many different molecules operate in autocrine-paracrine manner to guarantee tissue homeostatsis in physiological and pathophysiological conditions. In this paper we examined NGF and p75 receptor expression in the skin, during CFA induced inflammation, in a time-course study. We also examined cutaneus innervation and proliferation, by means of immunohistochemistry and quantitative image analysis, RT-PCR and Western blot. Spontaneous and evoked pain-behavior was also measured in experimental rats. The main results can be summarized as follows: 1). a peripheral sensory neuropathy develops in this condition, as indicated by thermal hyperalgesia, thus leading to a sensory denervation of the hind-paw skin as indicated by disappearance of CGRP and PGP9.5-IR fibers; 2). NGF and p75 expression (mRNA and protein) increases in the skin (keratinocytes) in the acute phase of CFA inflammation; 3). at this stage, a higher proliferative activity is observed in the skin, as defined by the expression of cell cycle-associated protein Ki67; 4). in the long-lasting chronic phase there is a further up-regulation of NFG and p75 expression in the skin; 5). trkA mRNA expression inversely correlates with p75 and NGF mRNA expression. These results suggest that CFA chronic inflammation evolves from inflammation to a small fibers sensory neuropathy and NGF seems to play a role in both events.

Class-wide resistance (CWR) was increasingly associated with a higher risk of HIV progression after 72 months of follow-up among 1392 patients genotypic-tested after failure (AIDS risk 13% for no CWR to 34% for three CWR; AIDS/death risk 21-54%). At multivariate analysis, the detection of two and three CWR was significantly associated with a two and threefold increased risk, respectively, of death and AIDS/death, suggesting that extended resistance is a marker of disease progression in long-term observation.

Background: The aim of this investigation was to verify whether brain hypoxia represented a risk factor for the occurrence and severity of opioid abstinence syndrome., Methods: Three newborns who manifested seizure activity as a result of hypoxia, focal brain ischemia, and hypoxia and sepsis, respectively, were compared with 17 neonates who suffered from hypoxia without developing seizure activity., Results: The first three neonates suffered a severe withdrawal syndrome (a rating on the neonatal abstinence score>17), the others did not., Conclusions: It is hypothesized that brain hypoxia facilitated the occurrence and severity of the withdrawal syndrome because some key neurochemical processes (such as N-methyl-D-aspartate activation, protein kinase C activation and nitric oxide production) are common to both phenomena.

Spasticity is a characteristic and early component of the lesions of the pyramidal tract of demyelinising diseases such as multiple sclerosis, and is included in the chief neurological scales to evaluate this disease. We report the case of a woman with a clawed toes deformity caused by spasticity of the extensor digitorum (longus and brevis) muscles.

Venous flow pattern changes and venous flow were assessed in relation to the degree of hemodilution. Femoral vein flow was measured with a duplex scanner in two groups of 11 patients 20 days and 5 days preoperatively, and 1 day postoperatively. In group I, hemodilution was used and patients gave three autologous blood predonations between day 20 and day 5. Perioperative blood loss was reintegrated by electrolyte solution. In group II, hemodilution was not used and autologous blood predonations were not carried out. These patients received a perioperative homologous blood transfusion of 800 mL. Hemoglobin was lower on day 5 (11.3 +/-1.4 vs 13.1 +/-1 g/dL, p<0.05) and on postoperative day 1 (8.9 +/-1.6 vs 10.6 +/-1, p<0.05) in group I. The decrease in hemoglobin was associated with an increase in blood flow and a pulsed venous flow pattern in 14 of 22 veins after autologous blood predonation and in 21 of 22 veins on postoperative day 1 (p<0.05). Increased venous flow in hemodilution is associated with a pulsed venous flow pattern.

Alongside the technique based on the creation of an abdominal cavity for surgery following the introduction of gas (usually CO2) into the peritoneal cavity, a new method has been developed. This involves the use of an atraumatic mechanical lifting device connected to the same abdominal wall (gasless laparoscopy). The authors report a technique that uses an inflatable cushion inserted into the abdomen through a periumbilical incision. The cushion is connected to an external motorized hydraulic jack fixed to the operating table, fitted with an electric motor and friction gear. Between May 1991 and June 1998, 580 patients underwent laparoscopic cholecystectomy. Since December 1995 a total of 130 patients have undergone surgery using gasless laparoscopy. Shoulder pain and pain in the upper abdominal quadrant were no longer reported; pain was present in 70% of the patients operated using the CO2 technique. There was also a marked reduction in the anesthesiological risks, above all in elderly patients with cardiopulmonary insufficiency. Surgical manoeuvres are made easier owing to the possibility of using traditional surgical instruments. Washing and continuous aspiration allow a good control of intraoperative hemostasis, and reduce the phenomenon of lens misting without the risk of losing pneumoperitoneum. Less visibility of the surgical field was reported, particularly in obese patients, above all because of the reduced diaphragmatic distension and the lack of displacement of the intestinal loops. In the authors' opinion the gasless technique is suitable above all in patients affected by cardiopulmonary disorders in whom hypercapnia might represent a significant operating risk.

The authors study the behaviour of the middle colic, left colic superior, middle and inferior and the first sigmoidal arteries in the territory of the terminal portion of the transverse colon, the left colonic flexure and the descending colon. The study was carried out on 1200 angiographies of the superior and inferior mesenteric aa. and on 150 anatomical specimens, surgically extirpated in the course of left emicolectomy operations. Contrary to what is believed by most authors, the left flexure is a colonic tract very well supplied by blood while the descending colon results to be poorly supplied, being served only by one artery (the left sup. colic a.) often of limited caliber and with branches (the middle and the inf. left colic aa.) sometimes totally or partially lacking. In this last colonic tract the vascular continuity, represented by the arterial arcades, is often interrupted. The Riolan's arcade, variously shaped, is to be considered a constant vascular structure (only once it was lacking in this study). Sometimes it is doubled by a second more internal arcade which must not be confused with the intermesenteric arcade. In four of the observed cases, the Riolan's arcade resulted strengthened by a second retroperitoneal arcade, derived from a branching of the middle colic a., whose branches of division went to the two colonic flexures and descended along the postero-lateral walls of the ascending and descending colon, often parallel to the regular abdominal branches. Exceptionally the colonic flexure is supplied by the only left colic a., which behaves as a specific artery, by us called "dominant artery". The central branches of the artery go to the flexure while the lateral ones join the branches of the middle colic and the first sigmoidal aa., effecting tenuous connections, surgically unreliable. In this case the arterial continuity of the Riolan's arcade can be considered interrupted, at least for the surgical practice. The intermesenteric arcade, in its three forms (direct, mixed and indirect), was observed in 20% of the cases. The colic marginal a. is considered by the authors a tier of arches formed by the colic aa. The left colonic flexure is also supplied by particular vessels originated from the middle colic and the left colic aa. (angular branches and arcades and bridge-branches) or from the superior mesenteric a. (angular artery of Donati) and from other sources, particularly from the splenic a. These vessels then join the colic "vasa recta" through the phrenocolic ligament and the marginal omental vessels. This research shows that the vascular continuity of the left colon is not a constant element, able to reassure the surgeon, for possible interruptions that may occur in its composition.

The authors report a controlled series of 40 patients treated for recidivating inguinal hernia and laparocele with the implant of alloplastic material. Short-term prophylaxis with vancomycin was performed in all cases. The antibiotic was found to be well tolerated at the doses used and this was associated with a good clinical success rate. The use of vancomycin in prophylaxis for this type of surgery is considered a rational choice and the use of short-term prophylaxis reduces the risks linked to possible collateral effects.

A preliminary identification of endogenous and exogenous methylated purine bases in urinary extracts of healthy and tumor-bearing subjects has been performed using high performance liquid chromatography, and tandem mass spectrometry (MS/MS). MS/MS gave particularly fast and sensitive analyses, allowing the simultaneous and rapid determination of 26 different urinary methylated purines. Both sets of data confirm that tumor-bearing patients show changed levels of methylated purine bases.

Background/aims: Colon cancer is one of the major health problems in industrialized countries, and its incidence appears to be increasing. Surgical resectability is the most important prognostic determinant, although despite apparently curative surgery, recurrent tumors are common. Metastatic disease cannot be cured, and thus, there is a need for better adjuvant therapies., Methods: Two hundred and thirty-nine patients with surgically resected colon cancer in Dukes' stage B2 or C were randomly assigned to chemotherapy or observation alone to determine whether adjuvant chemotherapy could effectively reduce the rate of cancer recurrence. One hundred and twenty-one patients in stage B2 and 118 patients in stage C were enrolled in the study. Adjuvant treatment consisted of folinic acid 200 mg/m2, intravenously, plus 5-fluorouracil 400 mg/m2, intravenously, on days 1-5 every 4 weeks for 12 cycles., Results: In stage B2, no significant difference between the adjuvant arm and the observation arm was noted. In stage C, adjuvant chemotherapy produced an advantage over observation in terms of a reduction in cancer recurrence rate with prolongation of a disease-free interval (P = 0.0016) and an improvement in overall survival (P = 0.0025)., Conclusions: This study shows that folinic acid plus 5-fluorouracil adjuvant chemotherapy is effective in patients with surgically resected Dukes' stage C colon carcinoma.

The 100-fold increase in toxicity of intraperitoneal (i.p.) rather than orally administered 2-t-butyl-4-methoxyphenol (BHA) is adduced to the depressive effect which this compound exerts on the contractility of the gut musculature. A structure/activity relation study shows the t-butyl group on the benzene ring as being the major determinant of i.p. BHA toxicity. Contractile activity, elicited by field electrical stimulation, acetylcholine or Ba2+, of the ileum longitudinal muscle preparation from BHA-treated rats was greatly reduced 30 min after i.p. injection, and almost absent during the subsequent 48 h. Electron-microscope examination of ileum longitudinal muscle also showed partial destruction of cell membranes 4 h after BHA administration with subsequent mitochondrial swelling and destruction of cristae, myofibrillar fragmentation and cell necrosis. Comparable suppression of contractile activity and morphological damage were observed in BHA or t-butylbenzene incubated ileum segments where longitudinal smooth muscle contractility was irreversibly depressed in a time- and dose-dependent manner. These convergent findings point to the toxic effect of i.p. BHA on gut musculature with consequent impairment of intestinal transit.

We report on a female infant who presents a pattern of malformations including dysmorphic facies, Dandy-Walker anomaly, hypoplasia of the upper lobe of the right lung, associated with diaphragmatic elevation and slight digital anomalies. This whole clinical picture allows us to formulate the diagnosis of Fryns syndrome; this is one of the very few not lethal cases that are reported in literature.

Histologically diagnosed, or in part questionable, malignant pleomorphic peripheral T-cell lymphomas (pPTCLs, n = 16) and mixed-cellularity Hodgkin's disease (MCHD, n = 12) were objectively compared by the use of combined immunohistochemistry on paraffin sections, test-point analysis of tissue components, and semi-automated nuclear morphometry on semi-thin resin sections. Classical, qualitative histomorphological distinction of these sub-types of lymphomas proved to be valid and is probably still the best method. Quantitative discriminant features, in order of decreasing significance, were: (i) expression by large atypical cells (LACs) of CD45R0, CD43 and CD45 in pPTCLs, and of CD30 and CD15 in MCHD; (ii) means and standard deviations (SDs) of LAC nuclear-profile areas (greater in MCHD than in pPTCLs); (iii) expression of CD3 by LACs in pPTCLs; (iv) prominence of small lymphoid cells in MCHD; (v) higher percentage of medium-sized lymphoid cells in pPTCLs; and (vi) higher SDs of nuclear-profile circularity factor of small lymphoid cells in MCHD. The medians of the largest nucleolar profile areas in LACs per field did not differ in pPTCLs and MCHD, but dispersion of individual values towards higher levels was significantly greater in the latter. Stepwise discriminant analysis of test point and nucleometric variables that best distinguished pPTCLs from MCHD revealed considerable overlaps, and questionable cases tended to be intermediate between the two. In conclusion, our results confirm and expand the notion of intra-group heterogeneity, with indistinct borders and the existence of intermediate phenotypes between these two taxonomic categories of malignant lymphomas.

The authors report the results of their observations on the lowest sigmoid artery, carried out on 92 anatomical specimens coming from surgical operations on the sigmoid and rectum. The specimens were injected and radiographed immediately after their removal . The observations were often preceded by pre-operative angiographies performed for diagnostic reasons. The AA. document all the variational patterns of this artery. They confirm the poor functional value of this artery more known by the old surgeons than by the anatomists.

In a case-control study of gastric cancer (GC) in high-risk and low-risk areas of Italy, 923 GCs were systematically categorized by one pathologist according to the Lauren classification distinguishing 2 main histologic types, intestinal (55%) and diffuse (23%). Intestinal types outnumbered diffuse types by a 3 to 1 margin in high-risk regions in the north-central part of the country, while both types occurred at nearly equal rates in low-risk areas. Intestinal types also occurred relatively more frequently at older ages and among males. Relative risks of each type of GC were evaluated in relation to dietary and other data obtained from interviews with the cancer patients and controls. The risk patterns for intestinal and diffuse types were remarkably similar. Increased risks of both types were associated with high intake of meat, salted/dried fish, seasoned cheeses and traditional soups, while decreased risks of both types were found among heavy consumers of fresh vegetables and fruits. Correspondingly similar patterns were seen with indices of nutrients, with risks of both intestinal and diffuse GC rising with animal protein intake and declining with consumption of vitamins C and E. Both types were inversely related to socio-economic status, and neither was associated with cigarette smoking. A familial history of GC was reported more frequently by patients with each type than by controls, although the highest risk was for unclassified GC, a group of poorly differentiated and medullary carcinomas accounting for 15% of all GCs in this study. The findings suggest that, despite differences in geographic and demographic patterns, the intestinal and diffuse types of GC have etiologic factors in common.

N-nitrosoproline (NPRO) excretion, an indicator of endogenous nitrosation, was measured in a group of hospital inpatients who were identified by endoscopy and gastric biopsy as either having gastric lesions or having healthy stomachs. NPRO was assayed in background 24-hour urine samples and samples collected after loading doses of nitrate and L-proline. The presence of gastric lesions was associated with altered gastric pH and concomitant changes in gastric juice nitrate and nitrite concentration. Gastric juice pH increased with increasing severity of gastric disease (P = 0.031) and patients with normal stomachs had a lower gastric pH than those with chronic atrophic gastritis (CAG) (3.0 vs. 6.5, P = 0.017). The changes in gastric juice nitrate concentration were in the reverse direction (P = 0.002 for trend) with normal patients having higher mean levels than CAG patients (12.7 vs. 5.5 micrograms/ml, P less than 0.0001). Nitrite concentration increased with severity of gastric disease but the results were not significant (normal, 82.9 vs. CAG, 223.4 ng/ml, P = 0.069). No association was found between the presence of gastric lesions and increased urinary NPRO excretion. Mutagenic activity was not detected in any of the gastric juice samples.

The author report the observations carried out on the distal part of the hemorrhoidal artery, obtained with a research on the vascularization of the large intestine, studied by the angiographic method and injection of the c.m. in the anatomical specimen immediately after surgical extirpation. The study was based on 92 anatomical specimens and reveals a variability of the terminal arterial distribution which can be summarized in few more frequent models, but cannot be given an absolute rule.

We report an unusual case of primary intrathoracic extrapulmonary hemangiopericytoma. Despite the large size and rapid growth of the tumor, no histological sign of malignancy was present. Tumor cells immunostained positively only to vimentin.

Personal experience about 11 cases of spontaneous biliary enteric fistula caused by lithiasic disease operated in the General Surgical Clinic of the University of Siena from 1969 to 1988, is reported. The epidemiology, pathogenesis, symptomatology, indications for operation and various operating techniques performed are discussed. In the gallstone intestinal obstruction, the authors prefer to resolve immediately the obstruction, deferring to a later moment the specific operation for the treatment of the biliary enteric fistula and the lithiasic disease.

The aim of this study was to study ultrastructural changes and lipid peroxidation in rabbits lung after massive complement activation and leukocyte aggregation. A prolonged and massive leukocyte activation was induced by intraperitoneal inoculation of zymosan suspected in paraffin. Fifteen animals (group 3) were given 0.6 g/kg of zymosan, 22 animals (group 2) received 1 g/kg, and 11 rabbits (group 1) were treated with paraffin alone and served as controls. An acute mortality rate of 40% was observed in group 3 and of 68% in group 2. Surviving animals were studied for 10 days. In these animals a marked decrease in circulating granulocytes and a progressive decline in arterial PO2 were recorded (PO2 on day 10 in group 2 animals was 51.94 +/- 4.26, p less than 0.01). Microscopic and ultrastructural evaluation revealed sequestration of granulocytes in the pulmonary microvasculature. Studies of lung homogenates demonstrated increased levels of lipid peroxide derivative malondialdehyde (group 2 rabbits, 1624 +/- 638; group 1, 795 +/- 57 pm/mg pt, p less than .001) and decreased levels of the tissue antioxidant alpha-tocopherol. The results of this study are compatible with the hypothesis of leukocyte-mediated injury through production of oxygen radicals.

Seventeen cases of acute volvulus of the sigmoid colon are presented. Comparison with other series showed that the mortality rate for fixation with or without a shunt are more or less the same. Excellent results were obtained with the Paul Mikulicz method. An intention to use this method in all cases in the future, irrespective of the patient's local and general condition, is expressed.

A case of bone stone in association with a papillary transitional cell carcinoma of the renal pelvis is reported. This type of lithiasis, actually representing bone metaplasia, is rare in the urinary tract and has never been reported in true epithelial urinary tumors.

Nine cases of primary gastric lymphoma are reviewed. Clinical data are correlated with histopathology and immunohistochemical findings. The reported observations suggest a relationship between associated lesions (chronic gastritis, follicular gastritis) and primary gastric lymphoma.

The Authors briefly report the data obtained from a study of the blood supply to colonic flexures. In spite of many Authors' different opinions, colonic flexures are adequately supplied by the same colonic arteries through secondary vessels as well as by the blood flow of other vascular regions.

Personal experience acquired in the use of radical and palliative techniques in the treatment of 18 cases of carcinoma of the pancreas and 1 of carcinoma of the ampulla hepatopancreatica is reported. The results show that duodenocephalo-pancreasectomy is a sound procedure, particularly in the absence of lymph node invasion. Operative mortality is low if the surgeon is experienced. In the even of serious and prolonged cholostasis, the operation can be preceded by a biliary shunt. According to the Authors there are not yet valid reasons as to the survival to prefer total pancreasectomy instead the partial pancreasectomy because of the high mortality of the former. Early diagnosis and the recognition of precancerous conditions still represent determining factors as far as operability and hence survival are concerned. The efficacy of chemotherapy is uncertain at present.

Prolapse of the rectum in adults has a complex etio-pathogenesis which involves a number of anatomical and physiological factors which, with the impulse of effort, cause the viscus to protrude externally through the sphincter. About one hundred operations have been designed to treat this condition, inspired by various mechanisms which have been considered to be responsible or involving excision of the prolapsed viscus. The results have been disappointing in view of the high rate of recurrence. At the present time, we prefer operations which anchor the rectum to posterior osseous structures, which are well tolerated, even by elderly patients. The immediate and long term results of these operations are very satisfactory. The author presents his experience of one of these operations.

An observed case of macroamylasaemia is presented with a description of the identification technique employed. As in cases reported in the literature, antiglobulin sera did not precipitate the complexes. This would appear to exclude the possibility of the immunity-related aetiopathogenesis the patient's immunological and electrophoretic patterns suggested.

N-Nitrosoproline (NPRO) excretion was measured in a group of hospital in-patients who were identified as either bearing gastric lesions or having apparently healthy stomachs. NPRO was assayed in background 24-h urine samples and then in urines collected after loading doses of nitrate and proline. The presence of gastric lesions was associated with altered gastric juice pH and nitrite concentration, but not with NPRO excretion. The significance of NPRO excretion as a marker of endogenous nitrosation is dependent on the interpretation of this result.