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P Rossini

Publications and source records attributed to P Rossini.

At least 19 recordsLinked to original sources
PubMed2005

Atmospheric bulk deposition to the lagoon of Venice Part I. Fluxes of metals, nutrients and organic contaminants.

First available data on atmospheric fall-out were provided by sampling monthly bulk depositions in four sites inside the Lagoon of Venice (550 km2). Sampling was carried out monthly during the period July 1998-July 1999, in one site near an industrial area (Porto Marghera; site D), another site in the city of Venice (site A), and the remaining two in the southern- and northernmost ends of the Lagoon (Valle Figheri, site C; Valle Dogà site B). The following determinations were carried out for each samples: pH, conductivity, grain-size, particulate load, and dissolved nutrients (N, P). Samples were then subdivided into soluble and insoluble fractions, and Al, Ca, Na, K, Mg, Si, Mn, Fe, Zn, Ni, Cr, Cu, Pb, Cd, As, Hg, Ti, V, S, P, Se and Sb were analysed on both fractions. Total organic micropollutants (PAH, PCB, HCB, DDT, PCDD/F) were measured. As regards particle size distribution, there was great variability among sampling sites. The percentage of the < or =2 microm grain-size fraction was higher in the southern and northern ends of the Lagoon. Small differences were found among sites for major elements, whereas higher variability was observed for inorganic and organic micropollutants, with standard deviations between 20% and 60% of the fluxes measured. Major differences in annual fluxes between the most polluted sites (mostly D and A) and background (site B) were seen for Cd (0.26 vs. 0.06 mg m(-2) year(-1)), Hg (41 vs. 15 microg m(-2) year(-1)), PCB ( approximately 2500 vs. approximately 500 ng m(-2) year(-1)) and HCB ( approximately 8000 vs. approximately 1000 ng m(-2) year(-1)). Comparisons with previous data, collected in the periods 1993-1994 and 1995-1997, were only available for a few trace metals. A definite decline in the annual Pb flux in the city of Venice was detected, from 18 to 13 mg m(-2) in 1996/1997 and 1995/1996 respectively, to approximately 5 mg m(-2) in the present study. Total annual deposition was calculated by means of two different methods, which gave very similar results: (i) the mean value of deposition in the four sites was multiplied by lagoon area (550 km2); (ii) the monthly rain isopleths were combined to normalize deposition values. The figures are: 15-34 kg of Hg and Sb, approximately 200 kg of As, approximately 100 kg of Cd and PAH, 0.7-1.3 tons of Cr, Ni and V, more than 2 tons of Cu and Pb, 17 of Zn, 55 of total P, approximately 200 of Al, and 3900 of DIN. Total fluxes of organics inside the lagoon were: PAH approximately 100 kg; HCB approximately 1 kg; DDT approximately 0.4 kg. PCB and PCDD/F fluxes were approximately 500 g and approximately 10 g, corresponding respectively to 0.1 and 0.4 g I-TE. The correlations between fluxes of inorganic micropollutants and grain-size were significant. Multivariate statistical analysis was applied to investigate more accurately relationships between the insoluble and dissolved fractions of inorganic micropollutants and grain-size fractions. In particular, significant correlations were highlighted between the dissolved fraction of As and the < or =1 mum particle size fraction. Relations between levels of SigmaPCDDF, SigmaPCDD, PCB and PAH congeners and grain-size revealed significant correlation coefficients for the remote sites (B, C), and none in the urban and industrial sites (A, D). In particular, significant correlations were highlighted between SigmaPCDDF, SigmaPCDD and particle size fraction < or =2 mum, and between benzo(a)pyrene and PCB 167 and particle size fraction 4-8 mum.

Atmosphere↗
PubMed2005

Atmospheric bulk deposition to the Lagoon of Venice Part II. Source apportionment analysis near the industrial zone of Porto Marghera, Italy.

Multivariate statistical analyses were applied to measurements of atmospheric deposition of total particulate (TSP), inorganic elements (Al, Ca, Na, K, Mg, Si, Mn, Fe, Zn, Ni, Cr, Cu, Pb, Cd, As, Hg, V and S) and organic compounds (PAH, PCB, HCB and PCDD/F) collected in four stations, all located in the Lagoon of Venice. Aerosols at the scale of the basin (i.e., within a distance of 20 km) were mainly characterised by two end-members, one natural (composed of mineral particulate and marine spray) and one anthropogenic (with at least two different source components), affecting the sites in various ways. Variability at the two distant (>20 km) sites (Valle Dogà, Valle Figheri) was mainly due to natural components, whereas the other two stations (city of Venice, Dogaletto, approximately 5 km) were mainly impacted by industrial (and urban) sources. Total annual inputs were compared with the limits recently set by law (maximum allowed discharge=MAD). In the year of study, MAD values were exceeded for total As, Cd, Hg, Pb, dissolved Zn, PAH and PCDD/F. These results indicate that industrial sources gave rise to a quasi-permanent compositional (background) effect near the industrial area. The risk associated with atmospheric deposition should be quantified within the DSPIR framework to avoid future negative consequences in populations living in the vicinity of Porto Marghera.

Atmosphere↗
PubMed2004

Measurement of atmospheric deposition of polychlorinated dibenzo-p-dioxins and dibenzofurans in the Lagoon of Venice, Italy.

Data on atmospheric fall-out of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were provided by collecting bulk deposition in four stations inside the Lagoon of Venice. A total of 44 monthly samples was collected during the period July 1998-July 1999 in one site near an industrial area (Porto Marghera), one site in the city of Venice, and two sites in the southern- and northernmost ends of the Lagoon. Fluxes of PCDD/Fs were between 0.1 and 470 pg m(-2) d(-1), corresponding to 0-9.2 pg of 2,3,7,8-TCDD equivalents (TEQ) m(-2) d(-1), with a gradient increasing from remote to urban/industrial stations. Thus, annual deposition of PCDD/Fs to the Lagoon (total area=550 km2), calculated with various methods, turned out to be approximately 12 g, corresponding to approximately 400 mg TEQ. Significant differences were found among the stations, with a clear fingerprinting signature (PCDF/PCDD>1) of the deposition collected near Porto Marghera, and a reversed pattern (PCDF/PCDD<1) in the rest of the Lagoon, which pattern was similar to the sediments collected in the same locations. Lastly, the amount of bulk sigmaTEQ of all stations was compared with the guide values for dioxins in depositions proposed by De Fré et al. [Organohalogen Compounds 45 (2000) 324].

Air Pollutants↗
PubMed2004

Combination of ion beam stabilisation, plasma etching and plasma deposition for the development of tissue engineering micropatterned supports.

The performance of biomedical assays at both molecular and cellular level depends greatly on the ability to design new polymer surfaces. Patterns can be created by using materials with contrasted surface properties. In this work we describe in detail the preparation of micropatterned surfaces to be used as tissue engineering supports. Poly(ethylene glycol) (PEG) was used as the 'anti-fouling' polymer in opposition to functional regions covered by acrylic acid (AAc). Since spin-casted PEG films are unstable, ion beam stabilization (IBS) treatment was applied in order to render it insoluble. On the other hand, AAc films were deposited by low-power plasma chemical vapour deposition. Chemical properties of both polymers were monitored by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy while topographic features were followed by atomic force microscopy. Finally, a micropattern was produced by using a mask, which isolated the IBS-PEG from the AAc-deposited regions. Endothelial cells cultured on the surface were observed to follow the micropatterns. In fact, for a certain surface density it was observed that the cells present tensile or compressive stresses when forced to remain in the anti-fouling or the functionalised regions, respectively.

Acrylates↗
PubMed2002

Prevalence of the E1317Q variant of the APC gene in Italian patients with colorectal adenomas.

Loss of APC is an initial, rate-limiting event in inherited and sporadic colorectal tumorigenesis. Rare germline APC mutations have been identified in patients with multiple colorectal adenomas. Recently, the E1317Q APC variant has been associated with a predisposition to the development of multiple colorectal adenomas. In this study, the prevalence of the E1317Q variant was examined in 182 patients with single or multiple colorectal adenomas, and in 235 controls. In all, E1317Q was identified in two of 182 patients with adenomatous polyps (1.1%) and in two of 235 controls (0.8%) (p = 0.59). The risk of harboring adenoma(s) among subjects bearing the E1317Q variant was 1.29 (95% CI 0.09-18.0). No difference in the prevalence of E1317Q between cases with single (2.0%) or multiple colorectal adenomas (0.7%) and controls (0.8%) was found. None of the subjects with a family history of colorectal cancer carried the E1317Q variant. In conclusion, our results confirm that only a very small fraction of colorectal adenomas may be associated with the presence of E1317Q.

Adenoma↗
PubMed2002

[Topical anesthesia for cataract surgery with phacoemulsification: lidocaine 2% vs ropivacaine 1%. Preliminary results].

BACKGROUND: The safety, tolerability and efficacy of ropivacaine 1% vs lidocaine 2% for phacoemulsification using topical anesthesia during cataract surgery, are compared. METHODS: A prospective, randomized, double-blind study comparing two agents for topical anesthesia is reported. ENVIRONMENT: Operative Unit of Ophthalmology, general Hospital. 1893 consecutively patients were studied (ASA 1-3, 738 males, 1155 females, age 71.8+/-9.7 years, range 35-90 years) undergoing routine phacoemulsification under topical 2% lidocaine (group I) and 1% ropivacaine (group II). The mains outcome measures of the study were: - the total dose of local anesthetic for obtaining a reduction of corneal sensation measured with the Cochet-Bonnet esthesiometer (value>3); - the pain recorded with visual analogic scale and verbal scale at: T1 = the first injection of local anesthetic; T2 = corneal incision; T3 = the end of surgery; T4 = 1h after surgery; T5 = the first postoperative day; - any requirement for additional intraoperative injection anesthesia and systemic sedation when needed; - surgeon assessments of operative conditions and patient cooperation; - patients' subjective level of comfort; - complications. RESULTS: Topical anesthesia using lidocaine 2% was significantly more painful than the ropivacaine 1%. The onset of anesthesia adequate for surgery was similar in all two groups. There were differences between the groups with respect to perioperative analgesia because the VAS was significantly higher in lidocaine group than in ropivacaine group. There were no statistically differences between the two groups at the follow-up. Inadequate anesthesia was seen in 8.05% (74/919 patients) cases of group I vs 0.9% (22/974 patients) of group II. Sedation was needed only in 10 patients and 6 patients of group I and II respectively. The surgeon assessment showed more patient cooperation in the ropivacaine group (83%). Satisfactory comfort (level 1) was reported by 60.4% in the lidocaine group and 86.8% in the ropivacaine group. In both groups there were cases of postoperative epithelial edema (29 patients in group I vs 36 patients in group II) although it decreased after the first postoperative day. No other significant side-effects were observed with the use of either formulations. CONCLUSIONS: Lidocaine 2% and ropivacaine 1% were safe and effective agents in patients having phacoemulsification with IOL implantation. However, ropivacaine provides more good operative conditions than lidocaine for the surgeon and comfortable surgical circumstances for the patient.

Administration, Topical↗
PubMed2001

Effect of estradiol valerate alone or in association with cyproterone acetate upon vascular function of postmenopausal women at increased risk for cardiovascular disease.

OBJECTIVES: a large body of evidence has been accumulated suggesting that impairment of vascular endothelial function is an initial step in the development of atherosclerosis. Recent studies have shown that estrogen replacement therapy in postmenopausal women (PMW) improves endothelium-dependent, flow-mediated dilatation (FMD) while the cyclical adjunct of a progestin may reverse this effect. METHODS: the purpose of this study was to evaluate endothelium-dependent, FMD in the brachial artery and the plasma levels of Endothelin-1 in menopausal females treated with estradiol valerate with and without cyclical cyproterone acetate in 20 PMW (mean age 64+/-6 years) with more than one risk factor for coronary artery disease. After a baseline evaluation, PMW entered a double-blinded, placebo controlled single cross-over study and were randomized to receive either estradiol valerate (2 mg) for 21 days or estradiol valerate (2 mg) for 11 days and estradiol valerate (2 mg) and cyproterone acetate (1 mg) for 10 days. Patients were crossed-over the complementary treatment 7 days after completing the first treatment phase. The study of forearm blood flow was repeated at the end of each treatment period. RESULTS: estradiol valerate significantly increased FMD as compared with baseline (12+/-3 vs. 7+/-4%, P<0.01) the adjunct of cyproterone acetate did not affect the effect of estradiol valerate upon FMD (12+/-3 vs. 11+/-4%, P=NS). Similarly reactive hyperemic flow increased after estradiol valerate alone (24%) or in association with cyproterone acetate (24%) compared with baseline. Plasma levels of Endothelin-1 were significantly reduced by estradiol valerate alone or in association with cyproterone acetate. CONCLUSIONS: in conclusion hormone replacement therapy with estradiol valerate and cyproterone acetate improves endothelial function and reduces plasma levels of Endothelin-1 in PMW at risk of coronary artery disease. These effects may be relevant for cardioprotection.

Brachial Artery↗
PubMed2001

Mapping of early and late human somatosensory evoked brain potentials to phasic galvanic painful stimulation.

In the present study, we modeled the spatiotemporal evolution of human somatosensory evoked cortical potentials (SEPs) to brief median-nerve galvanic painful stimulation. SEPs were recorded (-50 to +250 ms) from 12 healthy subjects following nonpainful (reference), slight painful, and moderate painful stimulations (subjective scale). Laplacian transformation of scalp SEPs reduced head volume conduction effects and annulled electric reference influence. Typical SEP components to the galvanic nonpainful stimulation were contralateral frontal P20-N30-N60-N120-P170, central P22-P40, and parietal N20-P30-P60-P120 (N = negativity, P = positivity, number = latency in ms). These components were observed also with the painful stimulations, the N60, N120, P170 having a longer latency with the painful than nonpainful stimulations. Additional SEP components elicited by the painful stimulations were parietomedian P80 as well as central N125, P170 (cP170), and P200. These additional SEP components included the typical vertex negative-positive complex following transient painful stimulations. Latency of the SEP components exclusively elicited by painful stimulation is highly compatible with the involvement of A delta myelinated fibers/spinothalamic pathway. The topography of these components is in line with the response of both nociceptive medial and lateral systems including bilateral primary sensorimotor and anterior cingulate cortical areas. The role of attentive, affective, and motor aspects in the modulation of the reported SEP components merits investigation in future experiments.

Adult↗
PubMed2001

How progestins influence the cardiovascular effect of hormone replacement therapy.

Hormone replacement therapy aims to protect against osteoporosis and alleviate fastidious menopausal symptoms such as hot flushes, depression, sleep disturbances and vaginal dryness. In view of the acknowledgement of estrogen deficiency as a major trigger for the acceleration of cardiovascular risk after menopause, hormone replacement therapy may also be proposed as a substantial beneficial cardioprotective agent. The effects of progestins on lipoprotein profile and vasomotor tone are dependent on the chemical structure and the scheme of administration of progestins, with androgenic progestins and cyclical therapy having a potential detrimental effect. Prospective primary and secondary prevention studies, however, suggest that the adjunct of non-androgenic progestins to estrogen therapy is at least as effective as estrogen replacement therapy in reducing cardiovascular mortality and morbidity. Data from recent randomized secondary prevention studies have to be viewed with caution.

Animals↗
PubMed2001

Usefulness of histological examination for the diagnosis of onychomycosis.

BACKGROUND: [corrected] Direct microscopy and culture tests currently used in the diagnosis of nail mycosis can yield false-negative results, and confirmation of the pathogenic agent, especially in non-dermatophyte infections, is often a lengthy process. OBJECTIVE: The aim of this study was to investigate the usefulness of the histological examination of nail clipping samples in supplementing the standard microscopic and culture techniques for the diagnosis of onychomycosis. PATIENTS AND METHODS: One hundred and seventy-two subjects affected by nail alterations suggestive of onychomycosis were evaluated. Nail specimens were studied with 3 different techniques: direct microscopic examination of a 40% KOH clarified preparation, fungal culture and histological examination. Patients positive for fungal infection were re-evaluated with the same techniques after treatment with oral terbinafine, fluconazole or itraconazole and topical application of bifonazole or ciclopirox for 2 months. RESULTS: Direct microscopy was positive in 102 (59.3%) nail specimens. The culture test was positive in 90 cases (52.9%), showing a dermatophyte in 45, a yeast in 23 and a mould in 22 samples. The histological examination was positive in 94 (54.6%) samples. In 4 cases, it was the only investigation confirming the clinical diagnosis of nail mycosis. In most of the cases, the morphological aspect of the hyphae and/or spores suggested also to which group of pathogens (dermatophytes, yeasts or moulds) the mycetes observed in the histological sections could be ascribed. The concurrent presence of a dermatophyte and a mould was evidenced in a few specimens. The control histological examination at the end of the treatment showed negative results or residual non-vital hyphae and/or spores. CONCLUSIONS: Results of the present study indicate that the histological examination of nail clipping specimens is a relatively inexpensive, rapid and easily performed procedure. It is useful to confirm or refute the results of routine microscopy and culture tests. Moreover, nail histopathological observation may help in ascribing a pathogenic role of non-dermatophyte isolates and evaluating the effectiveness of antifungal treatment.

Adolescent↗
PubMed2001

Gated blood pool tomography for the evaluation of global and regional left ventricular function in comparison to planar techniques and echocardiography.

BACKGROUND: Multigated radionuclide ventriculography (MUGA) is a simple and reliable tool for the assessment of global systolic and diastolic function and in several studies it is still considered a standard for the assessment of left ventricular ejection fraction. However the evaluation of regional wall motion by MUGA is critical due to two-dimensional imaging and its clinical use is progressively declining in favor of echocardiography. Tomographic MUGA (T-MUGA) is not widely adopted in clinical practice. The aim of this study was to compare T-MUGA to planar MUGA (P-MUGA) for the assessment of global ejection fraction and to transthoracic echocardiography for the evaluation of regional wall motion. METHODS: A 16-segment model was adopted for the comparison with echo regional wall motion. For each one of the 16 segments the normal range of T-MUGA ejection fraction was quantified and a normal data file was defined; the average value -2.5 SD was used as the lower threshold to identify abnormal segments. In addition, amplitude images from Fourier analysis were quantified and considered abnormal according to three different thresholds (25, 50 and 75% of the maximum). RESULTS: In a study group of 33 consecutive patients the ejection fraction values of T-MUGA highly correlated with those of P-MUGA (r = 0.93). The regional ejection fraction (according to the normal database) and the amplitude analysis (50% threshold) allowed for the correct identification of 203/226 and 167/226 asynergic segments by echocardiography, and of 269/302 and 244/302 normal segments, respectively. Therefore sensitivity, specificity and overall accuracy to detect regional wall motion abnormalities were 90, 89, 89% and 74, 81, 79% for regional ejection fraction and amplitude analysis, respectively. CONCLUSIONS: T-MUGA is a reliable tool for regional wall motion evaluation, well correlated with echocardiography, less subjective and able to provide quantitative data.

Echocardiography↗
PubMed1999

Clinical and laboratory manifestations of elderly onset psoriatic arthritis: a comparison with younger onset disease.

OBJECTIVE: Although the influence of age on clinical and laboratory features has been widely demonstrated in many arthropathies, studies on elderly onset (> 60 years) psoriatic arthritis (EOPsA) are rare. This study compares manifestations at onset and two year outcome of EOPsA with those of younger onset PsA (YOPsA). PATIENTS AND METHODS: Sixty-six consecutive PsA patients with disease duration < 1 year, 16 EOPsA (> 60 years) and 50 YOPsA (< or = 60 years) were admitted to a prospective study. Clinical, laboratory, and radiographic assessment were carried out at admission and after two years. HLA class I and bone scintigraphy were also recorded. In 10 patients with EOPsA and 24 with YOPsA it was possible to obtain synovial fluid, which was subsequently analysed for local inflammatory indices, including interleukin (IL) 1 beta, IL6, and IL8. RESULTS: Presenting manifestations of EOPsA differed from YOPsA in number of active joints (mean (SD)) (12.2 (6.3) v 6.7 (4.6), p < 0.001), foot bone erosions (2.7 (1.2) v 1.1 (1.1), p < 0.001), erythrocyte sedimentation rate (64.2 (35.3) v 30.5 (30.0) mm 1st h, p < 0.001), C reactive protein (3.9 (2.0) v 1.3 (1.3) mg/dl, p < 0.001) and synovial fluid IL1 beta (8.0 (4.7) v 3.0 (3.0) pg/ml, p < 0.001) and IL6 (828.2 (492.6) v 469.3 (201.4) pg/ml, p < 0.005). No differences were found in the number of subjects with dactylitis, pitting oedema, HLA-B27, or signs of sacroiliac and sternoclavicular joint involvement at bone scintigraphy. After two years, progression was more evident in EOPsA than in YOPsA, as the number of new erosions in the hands and also the C reactive protein were higher in EOPsA patients. CONCLUSION: PsA has a more severe onset and a more destructive outcome in elderly people (onset > 60 years) than in younger subjects. This behaviour may be influenced by immune changes associated with aging, as suggested by the higher concentrations of IL1 beta and IL6 found in the synovial fluid of EOPsA than in YOPsA.

Adult↗
PubMed1998

Spectral analysis of intercycle heart fluctuations in the diethyl-ether-anaesthetized or pithed rat treated with prazosin, dl-propranolol, endothelin-1, alpha-r atriopeptin and ACE-inhibitors.

1. Frequency-domain spectral analysis of stationary ECG R-R intervals was made by fast Fourier transformation (FFT) in conditions of monitored arterial blood pressure and respiratory activity in diethyl-ether-anaesthetized and pithed adult rats. This technique yields a number of parameters which allow quantitative evaluation of the non-random distribution of the mean values obtained in time-domain studies. The frequency-analysis method enables the overall heart rate variability to be broken down into its various constituents, which are differently affected by physiological loading and capable of selective reactivity to pharmacological agents. 2. The low-frequency spectral component obtained by breaking down the total spectral density power, i.e. the appropriate variability signal (band width < 0.15 Hz) and a higher-frequency band corresponding to spontaneous (0.80-1.60 Hz) or artificially imposed (0.75 Hz) respiratory activity were estimated and their integrated areas evaluated as absolute powers or normalized fractional values. 3. The power of the high-frequency spectral component increased in all animal preparations under treatment with prazosin, dl-propranolol, endothelin-1 and the angiotensin converting enzyme (ACE) inhibitors captopril, lisinopril, quinapril and ramipril. The power of the low-frequency band increased under alpha-r atriopeptin and ACE inhibitors in the pithed preparations only, and decreased in the anaesthetized animals. 4. The new power spectrum features and trends detected indicate that these time-independent, model-dependent cardiovascular and respiratory markers are subject to some form of complex peptidergic control. 5. The relative roles of the various factors operating in the genesis of these short-term changes in spectral power in the low- and high-frequency bands cannot be interpreted as indicating a reciprocal push-pull relationship between sympathetic and parasympathetic control. 6. The study findings, however, can be interpreted as providing evidence of a different and to some extent alternative form of integrative cardiovascular control persisting in the pithed rats (i.e. in the 'peripheral', CNS-destroyed preparations). 7. New areas of theoretical and applied research are being developed in the (auto)classification of (iso)receptors and drug analogues through exploration of multiple physiological and pharmacokinetic parameters in the frequency-domain. Furthermore, model-independent frequency-domain methods not requiring stationary data will afford scope for even more significant developments by separating the overlapping dynamic processes from a whole series of correlated effects.

Animals↗
PubMed1998

Teaching sign language to hearing children as a possible factor in cognitive enhancement.

We describe an educational experience designed to teach Italian Sign Language (LIS) to a group of hearing children. The hypothesis underlying this experience was that learning a visual-gestural language such as LIS may improve children's attentional abilities, visual discrimination, and spatial memory. To examine this hypothesis, we conducted two studies. The first involved an educational experience lasting two years with a group of hearing children attending a Sign Language class from first to second grade. The Raven PM 47 TEST was administered at the beginning and at the end of each school year to children attending the LIS classes and to a control group of children enrolled in the same school but not exposed to LIS. The second study involved an educational experience in first grade. The Raven PM 47 and Corsi's block tapping tests were administered at the beginning and at the end of the school year to the children attending the LIS classes, to children enrolled in the same school but at tending an English class, and to children not exposed to a second language. We found that in both studies the LIS group performed better than the other groups. These results suggest that learning a sign language may lead to a cognitive advancement in hearing children.

Journal Article↗
PubMed1997

(ECTO) nucleotidase kinetics observed by 31P-NMR spectroscopy: resolution of signals.

We used 31P-NMR to study the action of the drug ouabain, a digitalis glycoside, on the ecto-nucleotidase catalysed reaction pathway: [formula: see text] Even under conditions where it was impossible to resolve all resonances from the individual species, the rate constants for the individual steps may be evaluated by a chi 2 fit of equations describing the global kinetics to the NMR data. The fitted values of the reaction rate constants show no inhibition of any step in the reaction pathway, confirming previous results. This improved kinetic method can be used to evaluate the effect of different substrates, ions and drugs, both in intact or pathologically altered organs and in tissue subcellular fractions.

Adenosine Triphosphatases↗