The impact of early surgical treatment of tracheal stenosis on neurorehabilitation outcome in patients with severe acquired brain injury.

INTRODUCTION: Acquired tracheal stenosis (TS) is a potentially life-threatening condition following prolonged intubation and/or tracheostomy in adult patients with severe Acquired Brain Injury (sABI), requiring a tracheal resection and reconstruction. METHODS: We included 38 sABI adult patients with TS, admitted at a post-acute Neurorehabilitation Hospital. Disability Rating Scale (DRS) and other functional assessment measures were recorded at admission (t1), before TS surgical treatment (t2), and at discharge (t3). Patients were defined as 'improved' when they changed from a more severe to a less severe disability, between time t2 and time t3, and as "not improved" when they did not show any further improvement between t2 and t3, or they already exhibited a disability improvement since time interval t1-t2. RESULTS: Time interval between the injury onset and TS surgical treatment (t2-t0) was associated with the patient's disability improvement, suggesting the t2-t0 time interval ≤ 115 days as a cutoff value for a possible functional recovery. A t2-t0 time interval ≤ 170 days is also associated to absence of persistent dysphagia. CONCLUSIONS: Early TS surgical treatment within 115 days from the injury onset contributes to the improvement of the disability level in patients with sABI, optimizing their functional outcomes and recovery potential.

Home accidents in the province of Trento. Ten years of observations regarding admissions to the emergency and first aid department.

BACKGROUND: Home accidents, or domestic accidents, are accidents that occur inside a home or the adjacent areas (stairways, courtyards, gardens, attics, cellars, garages, etc.). In Italy, they are monitored through a number of surveillance systems including the PASSI system and the ISTAT (Italian Institute of Statistics) Multipurpose Survey on Households. Only the SINIACA system (Italian National Information Service on Domestic Accidents), managed by the Istituto Superiore di Sanità (National Institute for Health), provides health-related information regarding such events and their circumstances and consequences, based primarily on Accident & Emergency Departments' data. STUDY DESIGN: This is an observational study on the domestic accidents trends in the province of Trento, using data on Accident & Emergency Departments admissions, between 2009 and 2018, combined with mortality and hospital discharge data. METHODS: The authors extrapolated records regarding admissions for domestic accidents from the digital annual Accident & Emergency admissions archive. For the 2009-2018 period, they analysed: the trend over time, both overall and classified according to gender and age group; and the inflow rate/10,000 inhabitants, broken down according to gender, nationality (Italians and foreign nationals) and age group. The coverage of the additional SINIACA variables regarding the accident dynamic, contingent activity and place of the accident were also analysed. With regard to the case load for 2018, the authors analysed the site and type of the injuries, the level of severity, outcome and the services provided, comparing the 0-14 years and >65 years age groups. Trend significance was analysed using the Cochran-Armitage test for trend and the significance of the differences between the proportions was analysed using the Chi-squared test. We have also calculated the costs of the services provided, overall and by age group. RESULTS: During the study period, a total of 99,386 A&E admissions for domestic accidents were recorded, with an annual average of 9,938 admissions. Between 2009 and 2018, there was a statistically significant increase of 41%, which was due in part to better event recognition and recording. Females prevail over males, especially over the age of 75 years. Over time there is an increase in cases over the age of 65, due to the progressive ageing of the population. Considering the resident population alone, the A&E inflow rate rises from 147 admissions/10,000 inhabitants in 2009 to 197 admissions/10,000 inhabitants in 2018, with a 39.0% increase. Inflow is greater in the two extreme age groups: in 2018, in the 0-4 years age group, the inflow rate is 319 admissions/10,000 inhabitants and in the over 75 years class it rises to 481 admission/10,000 inhabitants, 1.6 and 2.4 times the mean inflow for home accidents in the province of Trento, respectively. Admissions are less amongst foreign nationals than amongst Italians. Generally speaking, the events were of a mild severity, with white triage codes accounting for 16% of cases and green triage codes for 73%. The degree of severity is higher amongst subjects aged over 65, as well as in women and Italian citizens.The level of recording of SINIACA variables increases over time, to reach 100% coverage in 2018. Falls are the most common dynamic in all age ranges; household chores, activities of daily living and DIY are the three most commonly observed activities. Home accidents most commonly occur in the areas adjacent to the home and the kitchen. In over 2/3 of cases, the injuries sustained were to the limbs and the head/face. Head/face injuries prevail in the youngest age group. Wounds, burns and head injuries are the most common types of injury sustained by children in the 0-14 years age group, whereas fractures and dislocations are typical of the older age groups. Diagnostic and care resource consumption is far higher amongst the elderly, which absorb 61% of the total costs of the cases treated in the year 2018. CONCLUSION: Accident & Emergency facilities provide a privileged observatory for the monitoring of domestic accidents in the population. By comparing our data with the ISTAT data, it can be estimated that 1 in 2 home accidents in the population resulted in an A&E admission. Admissions increase over time, particularly amongst the elderly and they are not higher amongst foreign nationals than amongst Italians. The inflow rate is higher in the extreme age ranges: 0-4 and >75 years; however, there are differences between the two in terms of type of injury, level of severity and outcome. It is essential for A&E admission data to be fully digitalised, and facility and staff sensitisation is also important in order to guarantee the availability of good-quality data. The completeness of A&E data and the possibility of obtaining case stratification based on social and demographic characteristics could make it possible, through a virtuous integration of services, to use these data for the implementation of prevention initiatives. These, if carried out effectively, could also contribute to contain healthcare costs.

Effectiveness of face masks for the population.

Background: Health authorities and organizations consider non-medical face masks as an additional passive means to prevent virus diffusion. Communication strategies disseminate information among the population that such masks are essential for mitigating virus diffusion. However, scientific studies are not conclusive in showing the undisputed filtration efficiency of fabric/cloth facial masks (both commercial and homemade). Objectives: This study examines scientific data about the effectiveness of face masks before and during the COVID-19 emergency. Present trends in the making of commercial and homemade fabric/cloth face masks are also examined. Methods: Statistical data of published studies are analyzed and compared. Main considerations and sugge-stions are also extracted and discussed. Current approaches are examined for assessing the characteristics and effectiveness of fabric/cloth commercial and homemade face masks intended for the population. Results: Conflicting data exist as to whether non-medical masks have a protective effect from the spread of respiratory viruses. Both medical masks (MDs) and respiratory personal protection equipment (PPE) show a given effectiveness value. Conclusion: Concerning commercial and homemade fabric/cloth masks, giving general indications on the choice of materials and their assemblage is difficult as it is not possible to assess the effectiveness of the filter media with respect to the kind of multiphase fluid that may be emitted upon breathing, sneezing, or coughing under different environmental conditions. This is particularly important because airflow rate, temperature, humidity, and duration of use will affect the performance of filter media. Moreover, while a mask may have excellent filter media, droplets may leak into the face-piece unless there is an adequate facial seal. In the presence of leaks, any type of mask may actually offer less protection independently of its nominal filtering effìciency.

Nine-hour X-ray quasi-periodic eruptions from a low-mass black hole galactic nucleus.

In the past two decades, high-amplitude electromagnetic outbursts have been detected from dormant galaxies and often attributed to the tidal disruption of a star by the central black hole1,2. X-ray emission from the Seyfert 2 galaxy GSN 069 (2MASX J01190869-3411305) at a redshift of z = 0.018 was first detected in July 2010 and implies an X-ray brightening by a factor of more than 240 over ROSAT observations performed 16 years earlier3,4. The emission has smoothly decayed over time since 2010, possibly indicating a long-lived tidal disruption event5. The X-ray spectrum is ultra-soft and can be described by accretion disk emission with luminosity proportional to the fourth power of the disk temperature during long-term evolution. Here we report observations of quasi-periodic X-ray eruptions from the nucleus of GSN 069 over the course of 54 days, from December 2018 onwards. During these eruptions, the X-ray count rate increases by up to two orders of magnitude with an event duration of just over an hour and a recurrence time of about nine hours. These eruptions are associated with fast spectral transitions between a cold and a warm phase in the accretion flow around a low-mass black hole (of approximately 4 × 105 solar masses) with peak X-ray luminosity of about 5 × 1042 erg per second. The warm phase has kT (where T is the temperature and k is the Boltzmann constant) of about 120 electronvolts, reminiscent of the typical soft-X-ray excess, an almost universal thermal-like feature in the X-ray spectra of luminous active nuclei6-8. If the observed properties are not unique to GSN 069, and assuming standard scaling of timescales with black hole mass and accretion properties, typical active galactic nuclei with higher-mass black holes can be expected to exhibit high-amplitude optical to X-ray variability on timescales as short as months or years9.

Changes in Caregivers Lifestyle after Severe Acquired Brain Injury: A Preliminary Investigation.

INTRODUCTION: Severe acquired brain injury (sABI) is considered the most common cause of death and disability worldwide. sABI patients are supported by their caregivers who often exhibit high rates of psychological distress, mood disorders, and changes in relationship dynamics and family roles. OBJECTIVES: To explore lifestyle changes of caregivers of sABI patients during the postacute rehabilitation, by investigating possible differences between primary and secondary caregivers. Primary caregivers spend most of the time with the patient, providing daily care and taking most responsibility for the day-to-day decisions, while secondary caregivers are those who provide additional support. METHODS: Three hundred forty-seven caregivers of sABI patients were asked to fill in an unpublished self-report questionnaire to explore their possible lifestyles changes. RESULTS: A statistically significant difference was found between primary and secondary caregivers in time spent in informal caregiving (p<0.001). The primary caregivers reduced all leisure activities compared to secondary carers (p<0.05). CONCLUSIONS: By comparing the percentage of leisure activities performed by caregivers before and after the patient's sABI onset, all caregivers showed high percentages of changes in lifestyle and habits, even though primary caregivers reported more negative lifestyle changes than secondary caregivers. Further studies are needed to investigate needs and burden experienced by caregivers of sABI patients during the postacute rehabilitation phase, also in relation to the patients' outcome, to address support interventions for them and improve their quality of life.

Management and long-term follow-up of early stage H. pylori-associated gastric MALT-lymphoma in clinical practice: an Italian, multicentre study.

BACKGROUND/AIM: Data on management and long-term follow-up of Helicobacter pylori-associated MALT-lymphoma in clinical practice are scanty. We evaluate the long-term efficacy of H. pylori eradication on low-grade MALT-lymphoma, and the efficacy of further therapies in refractory patients. METHODS: This study enrolled patients with stages I-II(1) MALT-lymphoma and H. pylori infection. H. pylori eradication was attempted in all patients. Patients with lymphoma persistence or progression following H. pylori treatments received further lymphoma treatments. Both 5-year and disease-free survivals were calculated. RESULTS: Sixty patients (stage I/II(1): 50/10) were followed up for a median time of 65 months (range 7-156). H. pylori infection was successfully eradicated in 53 (88.3%) patients following three consecutive therapeutic attempts, and lymphoma regressed in 42 (79.2%) of these patients. Sixteen patients received anti-neoplastic treatments due to either lymphoma persistence or progression, and lymphoma was cured in 14 (87.5%) cases. At follow-up, lymphoma relapsed in 13/42 (30.9%) patients within a median time of 19 months (range 3-41), and all but 1 patient were cured with further therapies. Overall, lymphoma regression was achieved in 56 patients (93.3%). The 5-year and disease-free survivals were 94.7% and 74.6%, respectively. CONCLUSIONS: In clinical practice, a conservative approach with antibiotic eradication seems to be appropriate management for early-stage MALT-lymphoma, with oncologic therapy being reserved for those patients who fail to respond to H. pylori therapy.

Systematic review: Endoscopic dilatation in Crohn's disease.

BACKGROUND: Endoscopic dilatation for Crohn's disease has been evaluated only in some small and heterogeneous studies. AIM: To evaluate any association between the main clinical variables and endoscopic variables and the efficacy and safety of endoscopic dilatation in Crohn's disease. METHODS: A Medline search regarding pneumatic dilatation in Crohn's disease was performed. Several technical and clinical variables were extracted from each study to build up a descriptive, pool-data analysis. Data on individual patients were extracted from suitable studies to create a simulated population upon which a multivariate statistical analysis was performed. RESULTS: Thirteen studies enrolling 347 Crohn's disease patients were reviewed. Endoscopic dilatation was mainly applied to postsurgical strictures, being technically successful in 86% of the cases. Long-term clinical efficacy was achieved in 58% of the patients. Mean follow-up was as long as 33 months, corresponding to 800 patient years of follow-up. Major complication rate was 2%, being higher than 10% in two series. At multivariate analysis, a stricture length < or = 4 cm was associated with a surgery-free outcome (OR: 4.01; 95% CI: 1.16-13.8; P < 0.028). CONCLUSIONS: Endoscopic dilatation is an effective and safe treatment for short strictures caused by Crohn's disease, impacting substantially on the natural history of these patients.

Road safety and the tsunami of cell phones.

In the last years an extremely rapid massive diffusion of the cell phones is occurred. Currently in Italy, as in many other countries, almost all the youngsters and a lot of adults possess a cell phones. This device is enormously useful, but its use can determine negative effects on the user's attention, i.e. during vehicle driving. Numerous epidemiological studies show that cell phone use in driving determines a relative risk of causing a road accident around 4 (equivalent to driving with 0.8 g/l blood alcohol concentration), for both hands-held and hands-free devices. This risk doesn't seem well perceived from the Italian drivers: as our surveys show, the 2.5% of them use a cellular hands-held while driving. This situation appears to evolve toward more critical conditions, given the quick diffusion of ever more technologically advanced instruments, such as video-cell phones, mostly capable of capturing the attention, or TV-cell phones, with which the distracting occasions could be more frequent and prolonged. The use of the cell phone seems to imply an important risk for pedestrians: the first results of the monitoring results that we are producing on this matter in Rome show that the 5.5% of the pedestrians cross the road while talking with a hands-held cell phones, in the most of cases ignoring the traffic conditions at all. All this facts show the urgency to promote specific actions of prevention, in absence of which it is reasonable to foresee a consistent growth in the number of road traffic accidents. In our opinion it is necessary to capillarily inform the public of the signalled risks, possibly also in the advertising spaces of the producers and managers of the cellular telephony, apart obvious repressive actions on the use of the cell phones during the guide of a vehicle.

Colon cancer prevention in Italy: cost-effectiveness analysis with CT colonography and endoscopy.

BACKGROUND: Colorectal cancer (CRC) is a major cause of mortality in Italy. Although prevention of CRC is possible, its cost-effectiveness when applied to the Italian population is unknown. Recently, computerized tomographic colonography (CTC) has been proposed for CRC screening. AIM: To compare the efficacy and cost-effectiveness of CTC screening in a simulated Italian population with those of colonoscopy and flexible sigmoidoscopy (FS). METHODS: The cost-effectiveness of different screening strategies was compared using a Markov process computer model, in which in a hypothetical population of 100,000 50 year-olds were investigated by CTC, colonoscopy or FS every decade. Outcomes were projected to the Italian national level. RESULTS: CRC incidence reduction was calculated at 40.9%, 38.2%, and 31.8% with colonoscopy, CTC and FS, respectively. As compared to no screening, all screening programs were shown to be cost-saving, allowing a saving of 11 Euro, 17 Euro, and 48 Euro per person with colonoscopy, FS and CTC, respectively. FS appeared to be less cost-effective than CTC, whilst colonoscopy appeared to be an expensive option as compared to CTC. Undiscounted national expenditure was calculated to be 1,042,489,512 Euro, 1,093,268,285 Euro, and 1,198,783,428 Euro for FS, CTC and colonoscopy, respectively, as compared to 695,818,078 Euro without screening. CONCLUSION: CRC screening is cost-saving in Italy, irrespective of the technique applied. CTC appeared to be more cost-effective than FS, and it may also become a valid alternative to colonoscopy.

More than terminology: using ICNP to enhance nursing's visibility in Italy.

BACKGROUND: The International Council of Nurses (ICN) has elaborated an international terminology for nursing practice [International Classification of Nursing Practice (ICNP)] that can be useful to catalogue the problems of a nursing nature in diagnosis and also find a system for the classification of nursing activities. ICNP is also the reason why the Italian association Consociazione, representing Italian Nurses at ICN, through the School of Advanced Nursing of the University 'La Sapienza' of Rome, has set up a working group for the translation and experimentation of the ICNP version Beta 2. CONTENT: In this article the ICNP beta translation and validation into Italian is considered with some scenarios of how benefit could be derived by its utilization for nursing's visibility. The visibility of nursing care can be measured not only through patient outcomes but also by studying the existing data of patient care documentation. To have a common language and terminology in nursing is important for a universal understanding. RESULTS: Some philosophical reasoning on the genesis and development of ICNP is discussed along with arguments for and against nursing classification systems. Some findings on Italian experimentation for nursing documentation as well as economical analysis are reported along with a vision for future development and utilization.

Early clinical predictive factors during coma recovery.

In severe brain injury patients few studies have examined the role of early clinical factors emerging before recovery of consciousness. Patients suffering from vegetative state and minimally conscious state in fact may need variable periods of time for recovery of the ability to follow commands. In a previous study we retrospectively examined a population of very severe traumatic brain injury patients with coma duration of at least 15 days (prolonged coma), and we found, as significant predictive factors for the final outcome, the time interval from brain injury to the recovery of the following clinical variables: optical fixation, spontaneous motor activity and first safe oral feeding. Psychomotor agitation and bulimia during coma recovery were also favourable prognostic factors for the final outcome. In a further study, also as for the neuropsychological recovery, the clinical variable with the best significant predictive value was the interval from head trauma to the recovery of safe oral feeding. In the present study the presence of psychomotor agitation diagnosed by means of LCF (score 4 = confused-agitated) at the admission time in rehabilitation predicted a statistically significant better outcome at the discharge time in comparison with patients without agitation.

Effect of Italy's motorcycle helmet law on traumatic brain injuries.

OBJECTIVES: To evaluate the impact of a revised Italian motorcycle-moped-scooter helmet law on crash brain injuries. DESIGN: A pre-post law evaluation of helmet use and traumatic brain injury (TBI) occurrence from 1999 to 2001. SETTING: Romagna region, northeastern Italy, with a 2000 resident population of 983 534 persons. PARTICIPANTS: Motorcycle-moped rider survey for helmet use compliance and all residents in the region admitted to the Division of Neurosurgery of the Maurizio Bufalini Hospital in Cesena, Italy for TBI. OUTCOME MEASURES: Helmet use compliance and change in TBI admissions and type(s) of brain lesions. RESULTS: Helmet use increased from an average of less than 20% to over 96%. A comparison of TBI incidence in the Romagna region shows that there was no significant variation before and after introduction of the revised helmet law, except for TBI admissions for motorcycle-moped crashes where a 66% decrease was observed. In the same area TBI admissions by age group showed that motorcycle mopeds riders aged 14-60 years sustained significantly fewer TBIs. The rate of TBI admissions to neurosurgery decreased by over 31% and epidural hematomas almost completely disappeared in crash injured moped riders. CONCLUSIONS: The revised Italian mandatory helmet law, with police enforcement, is an effective measure for TBI prevention at all ages.

Gastric cancer prevalence in patients with liver cirrhosis.

An increased risk for gastric cancer in patients with liver cirrhosis has recently been reported in epidemiological studies. The present endoscopic study was performed to further evaluate whether people with cirrhosis are at increased risk for gastric cancer development. We reviewed the medical records of all cirrhotic patients referred to our Endoscopic Service for portal hypertension screening and, therefore, cases of latent gastric cancer were observed. For a comparison, the prevalence (age and sex standardized) of latent gastric cancer in the general population was estimated hypothesizing a latency period of 5 years. Overall, 1379 patients with cirrhosis were selected from a total of 15 791 endoscopically examined different patients observed during the period 1982-1997. Histological assessment revealed the presence of gastric cancer in 10 patients (9 males and 1 female). There was a significant 2.6-fold (P<0.01) increase in prevalence of gastric cancer compared with that expected in our cirrhotic patients. In conclusion, our findings confirm that liver cirrhosis would seem to be a risk factor for the development of gastric cancer. Other studies are needed to evaluate the pathogenic mechanisms involved.

Long-term outcome of endoscopic pneumatic dilatation in Crohn's disease.

BACKGROUND: To avoid multiple surgeries in stenosing Crohn's disease, pneumatic endoscopic dilatation has been introduced. The present study evaluated the long-term clinical outcome in Crohn's disease patients after endoscopic dilatation for ileal or neoileal strictures. PATIENTS AND METHODS: All Crohn's disease patients who underwent pneumatic dilatation of ileal or ileo-colonic strictures between January 1988 and December 2001 were invited to return for a clinical check-up in June 2002. Clinical, endoscopic and radiological reports were reviewed. Symptomatic relief from sub-occlusive symptoms without requiring surgery was considered as a positive outcome, whereas the requirement of surgery was regarded as an unfavourable outcome. Possible predictors of favourable outcome were analysed. RESULTS: Endoscopic dilatation was technically successful in 34/43 (79%) Crohn's disease patients, with a mean number of dilatations per patient of 3 +/- 3.13. During a mean follow-up of 63.7 +/- 44.6 months, a positive long-term outcome was observed in 18 (52.9%) patients, whereas surgery was necessary in the remaining 16 cases. The risk of surgery was distinctly higher within 2 years post-dilatation than in the next 2 years (26.4% versus 8.3%, respectively; P = 0.078). No clear clinical, endoscopic or radiological predictive factors for a successful outcome were identified. CONCLUSIONS: Endoscopic pneumatic dilatation is an effective and safe procedure to be applied to patients with stenosing Crohn's disease, offering a very long-term benefit in a sub-group of patients.

[Italian translation and validation of the ICNP Beta (International Classification for Nursing Practice]. / Traduzione e validazione italiana della Classificazione Internazionale per la Pratica infermieristica (ICNP Beta).

The visibility of nursing care can be measured through the results on the patient and studying the existing data on patient care. An important area is tied up for a common language and terminology because it is important to have a universal understanding. For this reason the International Council of Nurses (ICN) has elaborated an international terminology for Nursing Practice that can be useful to pick up and to catalogue the problems of nursing nature in diagnosis also finding a system of classification of the activities The Consociazione Association, as representative of the ICN in Italy, through the School of Advanced Nursing of the University "La Sapienza" of Rome, has set up a Working group for the translation of the document ICNP version Beta. The present article explains the difficulties related to the Italian translation, the working group, the procedure, the validation and the met problems along with a vision for the future development and utilization.

Peyronie's disease: prevalence and association with cigarette smoking. A multicenter population-based study in men aged 50-69 years.

OBJECTIVES: We present a multicenter, population-based epidemiological survey aimed at assessing the prevalence of Peyronie's disease (PD) and its potential risk factors in the general population. METHODS: In each of the ten centers throughout Italy, a uroandrologist contacted all the men in the age range 50-69 years registered with a general practitioner (GP). The subjects recruited were evaluated on the basis of their medical history, including alcohol consumption and cigarette smoking. The following questionnaires were administered: IIEF, IIPSS symptom score, premature ejaculation and PD. RESULTS: All the subjects registered with a GP were invited to participate in the study. Of the 1,180 subjects, 647 (53%) entered over survey. In this population, 46 cases of PD were identified, accounting for a prevalence of 7.1%. The prevalence rate increased with age even if the trend is not statistically significant. The multivariate analysis showed a significant correlation between cigarette smoking and PD, with an odds ratio (OR) of 4.6 (CL 95%) confidence limit 1.506- 14.287). Smoking as single variable had an OR of 7.2 (95% CL 2.34-24.93). No significant association was observed between PD and the other variables such as cardiovascular diseases, diabetes, hypertension and alcohol consumption. CONCLUSIONS: PD is a much more frequent condition in the general population than previously reported. According to our results, cigarette smoking may be considered a risk factor for developing PD. If further and more targeted studies confirm that giving up smoking may reduce the risk of developing PD, then there will be new prospects for primary and secondary prevention and for curbing the progression of the disease.

Histomorphometric assessment of bone turnover in uraemic patients: comparison between activation frequency and bone formation rate.

AIMS: The histomorphometric assessment of bone formation rate (BFR/BS) in bone biopsies from uraemic patients is of crucial importance in differentiating low from high turnover types of renal osteodystrophy. However, since BFR/BS relies on osteoblasts, activation frequency (Ac.f), encompassing all remodelling phases, has recently been preferred to BFR/BS. This study was carried out to consider whether estimation of Ac.f is superior, in practical terms, to that of BFR/BS in distinguishing between different rates of bone turnover in uraemic patients. METHODS AND RESULTS: Bone biopsies from 27 patients in predialysis (20 men and seven women; mean age 53 +/- 12 years) and 37 in haemodialysis (22 men and 15 women; mean age 53 +/- 12 years) were examined. The types of renal osteodystrophy were classified on the basis of morphology. Bone formation rate and Ac.f were evaluated according to standardized procedures. The Ac.f was calculated both as a ratio between BFR/BS and wall thickness (W.Th) and as a reciprocal of erosion, formation and quiescent periods (EP, FP and QP). Patients were affected by renal osteodystrophy with predominant hyperparathyroidism (two predialysis and 16 dialysis), predominant osteomalacia (three predialysis and seven dialysis) or that of advanced (nine predialysis and five dialysis) or mild (seven predialysis and four dialysis) mixed type or adynamic type (six predialysis and five dialysis). Activation frequency, which with either formula requires the measurement of W.Th, i.e. the thickness of bone structural units (BSUs), was not calculated in three dialysis patients with severe hyperparathyroidism and in one predialysis and four dialysis patients with severe osteomalacia, because only incomplete BSUs were found. In dialysis, EP was higher in the adynamic than in the other types of osteodystrophy. During both predialysis and dialysis, FP was higher in osteomalacia than in the other forms of osteodystrophy, and in adynamic osteopathy than in hyperparathyroidism or in advanced and mild mixed osteodystrophy. During predialysis and dialysis, QP was higher in the adynamic than in the other forms of osteodystrophy. Correlations were found between BFR/BS and Ac.f, during predialysis (r=0.97) and dialysis (r=0.95). CONCLUSIONS: The superiority of Ac.f in assessing bone turnover, in comparison to BFR/BS, is conceptual rather than practical. The highest values for FP in osteomalacia and for QP in adynamic bone allow a clearer characterization of these low turnover conditions.

Urinary deoxypyridinoline excretion for the evaluation of bone turnover in chronic renal failure.

BACKGROUND: The urinary excretion of deoxypyridinoline (DPD) was evaluated in predialysis chronic renal failure (CRF), together with intact PTH and several classic markers of bone turnover in order to assess whether urine free and total DPD excretion are equivalent parameters of bone turnover in CRF, and to evaluate the relationship between urine DPD excretion, PTH and the other bone markers. METHODS: The study was carried out in 94 patients with different degrees of renal failure due to various kidney diseases. Besides urinary DPD expressed as free DPD, total DPD, free/total DPD, free DPD/Cr and total DPD/Cr, the following determinations were made: intact PTH, bone alkaline phosphatase (BALP), total alkaline phosphatase (AP), osteocalcin (BGP), serum C-terminal telopeptide of collagen type I (ICTP) and hydroxyproline (OHpro). The patients were divided into 3 groups according to the increasing severity of renal failure (Ccr >40, 40-20, <20 ml/min). RESULTS: The ratio free/total DPD decreased (NS) with advancing renal failure, and was inversely correlated with total DPD excretion. While PTH increased progressively to about four times the values observed in the Ccr >40 group, there was a parallel increase only in BGP and ICTP, parameters retained in the serum with decreasing renal function, while AP, BALP, total DPD and OHpro did not change. However, significant correlations between total DPD/Cr and PTH, BALP, BGP and ICTP were also found. CONCLUSIONS: In CRF free DPD is an unreliable index of bone turnover due to a probable interference in its production from the peptide-bound DPD. Total DPD or total DPD/Cr are better used. In spite of the significant correlations observed in advanced renal failure between PTH and most of the parameters examined, a resistance of bone tissue to PTH action in CRF must be considered.

Cumulant analysis of charge recombination kinetics in bacterial reaction centers reconstituted into lipid vesicles.

The kinetics of charge recombination between the primary photoxidized donor (P(+)) and the secondary reduced quinone acceptor (Q(B)(-)) have been studied in reaction centers (RCs) from the purple photosynthetic bacterium Rhodobacter sphaeroides incorporated into lecithin vesicles containing large ubiquinone pools over the temperature range 275 K = (50 +/- 15) nm). Following these premises, we describe the kinetics of P(+)Q(B)(-) recombination with a truncated cumulant expansion and relate it to P(Q) and to the free energy changes for Q(A)(-)Q(B) --> Q(A)Q(B)(-) electron transfer (DeltaG(AB)(o)) and for quinone binding (DeltaG(bind)(o)) at Q(B). The model accounts well for the temperature and quinone dependence of the charge recombination kinetics, yielding DeltaG(AB)(o) = -7.67 +/- 0.05 kJ mol(-1) and DeltaG(bind)(o) = -14.6 +/- 0.6 kJ mol(-1) at 298 K.