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M Zappa

Publications and source records attributed to M Zappa.

At least 73 records · Page 4Linked to original sources
PubMed1996

Study of the molecular defects in glucose phosphate isomerase-deficient patients affected by chronic hemolytic anemia.

We have studied four unrelated Italian patients with chronic hemolytic anemia associated with glucose phosphate isomerase (GPI) deficiency. Using intronic primers, we were able to detect the gene alterations on the genomic DNA of the patients. Five different mutations were identified among the eight mutated alleles found: three missense mutations (301A,584T,1028G), one nonsense mutation (286T), and a four nucleotides deletion [Del 1473-IVS16(+2)]. All of these were new except for mutation 1028G, which was previously identified in a Japanese variant (GPI Narita). Two patients were homozygotes (301A/301A and 1028G/1028G), whereas the other two were compound heterozygotes sharing a common mutation [286T/584T and Del 1473-IVS16(+2)/584T]. The missense mutations were found to involve highly conserved amino acids, suggesting that these residues are crucial for the maintenance of the enzyme function. The mutation 286T results in a truncated protein of 95 amino acids in comparison with the 558 of the normal one. The four nucleotides deletion located at the junction of exon/intron 16(5'-TTGGTCGgtgagt-3') is the first GPI mutation affecting a splice site. Moreover one difference from the published sequence (473T-->G) was found in exon five in all of the eight alleles studied and in 30 normal subjects. Correlation was made between mutations, biochemical characteristics of the enzyme, and clinical course of the disease.

Adult↗
PubMed1996

Antenatal diagnosis of short-limb dwarfism: sonographic approach.

Based on the findings in 12 patients with skeletal dysplasia diagnosed antenatally, the authors propose a tailored approach to the evaluation of foetuses with shortened long bones, depending on the time of discovery, the degree of shortening and the associated findings. During the second trimester, a very short femur [2 standard deviations (SD) - 5 mm and less] most probably corresponds to a bone dysplasia, although the differential diagnosis is mainly early intra-uterine growth retardation, and the foetal skeleton should be surveyed completely in order to find supplementary features suggestive of dwarfism. Anomalies of long bones in their shape, thickness or contour, or spinal ossification disorders or undermineralisation (best evaluated at the level of calvarial bones) are most helpful in determining the type of dysplasia. A short femur (between 2 SD and 2 SD - 4 mm) may indicate growth retardation, a chromosomal anomaly or dwarfism. Follow-up examinations are mandatory in order to differentiate between them. During the third trimester a very short femur may indicate a bone dysplasia and the work-up should be the same as in the second trimester. A short femur may correspond to dwarfism of late development, a growth-retarded foetus or constitutional shortness. Various ratios, especially that of the femur/foot, are helpful in differentiating between them. In case of previous family history, a short or very short femur usually indicates recurrence of the dwarfism. In all cases of antenatal diagnosis, confirmation of the sonographic findings should be obtained either by foetal or neonatal radiographs. The approach proposed by the authors should provide sufficient information to counsel the family not only for the ongoing pregnancy but also for subsequent ones.

Bone and Bones↗
PubMed1996

Immunochemical vs guaiac faecal occult blood tests in a population-based screening programme for colorectal cancer.

Two faecal occult blood tests (FOBTs), Hemoccult II (guaiac based) and Hemeselect (immunochemical) were compared in a population screening for colorectal cancer on 24 282 subjects aged 40-70. Hemeselect was interpreted according to a lower (+ and +/-) and a higher (+) positivity threshold. A total of 8008 compliers were enrolled in the study. Positivity rates: Hemoccult = 6.0%, Hemeselect (+ and +/) = 8.2%, Hemeselect (+) = 3.1%. Among FOBT-positive subject complying with the diagnostic work-up, 22 had colorectal cancer (17 Hemeselect-positive (+), four Hemeselect-borderline (+/-), 15 Hemoccult-positive) and 166 subjects had adenomas (62 Hemeselect(+), 56 Hemeselect-borderline (+/-), 79 Hemoccult-positive) were detected. The positive predictive values (PPVs) for cancer were as follows: Hemoccult = 3.7%, Hemeselect (+ and +/-) = 3.8%, Hemeselect (+) = 8.4%. The PPVs for adenoma(s) were: Hemoccult = 19.7%, Hemeselect (+ and +/-) = 21.4%, Hemeselect (+) = 30.5%. The specificity for cancer was: Hemoccult = 94.1%, Hemeselect (+ +/-) = 92%, Hemeselect (+) = 97.1%. Ratios between detection rates of each test and expected incidence of colorectal cancer suggest that Hemoccult anticipates cancer diagnosis by approximately 2 years on average whereas the mean diagnostic anticipation of Hemeselect ranges between 2.5 and 3.2 years. Hemeselect is superior to Hemoccult as it is at least as effective but more efficient and acceptable than guaiac testing. Further evaluation of Hemeselect cost-effectiveness and sensitivity is needed in order to assess the optimal threshold of positivity and screening frequency.

Adult↗
PubMed1996

Erythropoietin production and erythropoiesis in compensated and anaemic states of hereditary spherocytosis.

A compensated haemolytic state is defined by decreased red cell life-span without anaemia, i.e. by increased erythropoiesis in the absence of the physiological stimulus for erythropoietin (Epo) production. We evaluated s-Epo levels and the expansion of erythropoiesis (as measured by circulating transferrin receptor, s-TfR) in 32 patients with hereditary spherocytosis (HS) with the aim of verifying whether the enhanced erythropoiesis of compensated haemolysis was Epo-dependent. 20 of the patients (62.5%) had normal Hb values (> 12 g/dl in females and > 13 g/dl in males). Their compensated haemolytic state was the result of up to 8.2 times normal s-Epo and up to 3.9 times normal s-TfR levels, which were maintained by physiological regulation of erythropoiesis, as documented by the inverse dependence of Hb on s-Epo levels. Considering that patients with iron-deficiency anaemia represented the predicted physiological Epo response to anaemia, the observed/predicted in s-Epo ratio (O/P ratio) was calculated in HS patients with anaemia and was used as an index of the adequateness of Epo production. All the anaemic HS patients had an O/P ratio > 1, documenting inappropriately high s-Epo levels. This work demonstrates that the compensated haemolytic state of HS patients is produced by an inappropriately high s-Epo level, and that the pattern of Epo overproduction is a biological characteristic of the disease.

Adolescent↗
PubMed1996

Colorectal cancer survival--population-based rates in the province of Florence.

This study aimed to evaluate survival in 2,339 colorectal cancer patients diagnosed in 1985-87 in the province of Florence, where the Tuscany Tumour Registry is active. The effect of sex, site (colon, rectum), sub-site, disease diffusion (localized, regional, distant, unspecified), year of diagnosis, place of residence (municipalities involved in the screening programme, Florence, others) and source of diagnosis (Center for the Study and Prevention of Cancer-CSPO, others) were evaluated. Five-year observed and relative survivals were 37.9 and 48.1% respectively. Five-year prognosis was worse in men, in older age groups, in advanced stages and in patients not diagnosed at the CSPO. No differences were shown in residents of municipalities involved in the screening programme. Relative 5-year survival in Florence was among the highest in Europe for cancers of both the colon and the rectum. Sex, age, disease diffusion and source of diagnosis showed an independent prognostic effect. The effect of screening was not evident, probably due to the low compliance during the period under study and to the use of a low sensitivity test.

Adult↗
PubMed1996

Does the classification system fit disease progression in perinatal human immunodeficiency virus infection?

The objective was to test the applicability of the new classification for paediatric human immonodeficiency virus infection. The person-time of each state, transition probabilities and survival (+/- standard errors) at 5 years, and median sojourn-time were calculated on 39 perinatally infected children followed up from the first month of life for a median of 64.5 (1.2-120.1) months. The person-times of the N2, N3, B1, C1, and C2 states were low. The transition probabilities and sojourn-times were similar for A (48.1 +/- 10.8%; 63.5 months), B (50.5 +/- 15.5%; 44.9 months) and C (74.6 +/- 15.1%; 43.1 months) clinical categories, which differed (p < 0.025) from the N category (87.9 +/- 5.5%; 12.05 months). The survival probabilities after 5 years of entering the A, B and C categories were 84.8 +/- 10.7%, 60.5 +/- 19.8% and 14.8 +/- 13.5%, respectively (p < 0.001). Immunological category 3 had lower transition probabilities and longer sojourn-times (58.8 +/- 16.6%; 53.3 months) than categories 1 (71.3 +/- 8.1%; 33.2 months) and 2 (75.6 +/- 10.5%; 19.8 months) (p < 0.01). The transition probabilities to C3 for states N3, A3 or B3 were 52.5 +/- 13.5%. In conclusion, the classification fits the clinical history better than the immunological history.

Age Factors↗
PubMed1995

Trends in cervical cancer incidence in the district of Florence.

The trend in cervical cancer incidence in the District of Florence from 1975 to 1989 was investigated. Tuscany Cancer Registry data were available since 1985. Incidence data from 1975 to 1985 were obtained through a retrospective survey of all the Departments of Pathology and Gynaecology in the district. Cytological screening for cervical cancer has been available in the district since 1973, and since 1980 active invitation of residents aged 25 to 59 years has been in use. A significant trend in decreasing incidence was evident for the overall population (P = 0.003) and for 40-49 (P = 0.028), 50-59 (P < 0.001) and 60-69 (P = 0.002) year age groups, whereas no significant trend was observed for the age group 30-39 years. An association between attendance to screening and reduced incidence was evident, in that a greater reduction was evident for those cohorts (ages 50-59 and 60-69) who had a higher compliance to screening 10-15 years before. If the decrease in cervical cancer incidence was spontaneous, a parallel decrease of CIN3, which is commonly assumed to be the precursor of invasive carcinoma, would be expected. On the contrary, the detection rate of CIN3 at first Pap test showed a significant increase in the study period. All these findings suggest that the observed reduction in cervical cancer incidence was mostly due to the effect of screening, and stress the need for optimising the coverage of the invited population.

Adult↗
PubMed1995

A model-based prediction of the impact on reduction in mortality by a breast cancer screening programme in the city of Florence, Italy.

The efficacy of breast cancer screening for women older than 50 years has been shown in several studies. Service screening is now ongoing or planned in several countries in Europe. MISCAN, a computer simulation programme, has been used to analyse data from the Florence District Programme (FDP) breast cancer experience. First, the model was fitted to the screening results for the period 1975-1986. A good correspondence between the model outcomes and the FDP results was achieved. It was then used to predict the impact on mortality of the new starting programme of the city of Florence (63,000 women, 50-69 years old). Assuming a 70% attendance rate, then for the city of Florence, 2563 screen-detected breast cancers are predicted for the period 1991-2020 out of the total number of 9095 breast cancers for all ages (28%). A total of 3720 deaths for breast cancer are expected without screening. An absolute reduction of 472 deaths (13%) is predicted for the whole population. The estimated number of years of life gained by screening until 2020 is 4354. Simulation by MISCAN has previously been a useful support tool for decision-making about screening. The present paper is the first based on a southern European experience. The possibility of applying MISCAN to predict the impact of a national programme in Italy is discussed.

Adult↗
PubMed1995

The detectability of breast cancer by screening mammography.

We reviewed 134 patients with breast cancer (screen detected = 85, interval = 49) who had been reported as negative at previous mammographic screening in the Florence District Programme. At prior mammograms review, 12% of the cases were classified as 'screening error' (suspicious signs missed owing to misperception or poor imaging technique), 26% as 'minimal signs present', 54% as 'radiographically occult' and 7% as 'radiographically occult at diagnosis'. These results are quite consistent with those recently reported for the Nijmegen screening programme. Screening errors may be reduced either by reducing the risk of misperception (double reading) or by improving imaging quality, but this would achieve earlier detection in a minority of cancer cases. Minimal signs of cancer were present 2 years before the diagnosis in over one-third of screen-detected cancers. Increasing screening frequency (from biennial to annual) may advance detection time of most 'screening errors' and of some cancers in the 'minimal signs present' and 'mammographically occult' categories, but this would almost double screening costs, and the benefit would probably be inferior to that obtained by doubling the population invited to biennial screening. Adopting less stringent criteria for referral to diagnostic assessment would probably lead to the detection of some cases in the 'minimal signs present' category. This seems to us a more convenient policy to adopt to advance cancer detection time, although it will also sharply increase referral rates and costs. As diagnostic assessment of minimal lesions is far from being 100% accurate, this policy would also considerably increase the frequency of unnecessary benign biopsies. All these negative effects might turn out to be unacceptable.

Adult↗
PubMed1995

Independent double reading of screening mammograms.

OBJECTIVE: To evaluate the cost effectiveness of independent double reading of screening mammograms. SETTING: Prospective study of 18,817 women undergoing first or repeat screening in a population based programme in the Florence district. METHODS: Mammograms were independently double read by experienced radiologists. Subjects with mammographic abnormalities reported by at least one reader were recalled for diagnostic assessment. The mean increase in recall rate, cancer detection rate, and screening costs attributable to double reading was calculated. RESULTS: Eleven of 125 cancers were detected by only one reader. The mean increase in cancer detection rate attributable to double reading compared with single reading was 4.6% (95% confidence interval (CI) 1.1 to 8.9). From a total of 748 cases referred for diagnostic assessment, 196 subjects were referred by one reader only. The mean increase in referral rate attributable to double reading compared with single reading was 15.1% (CI 12.3 to 17.8). Double reading caused a marked increase in the cost for each woman screened -8.5% at the first screening and 6.2% at repeat screening and a more limited increase in the cost for each cancer detected -3.5% at the first screening and 2.7% at repeat screening. Cancers detected by only one screener were at an earlier stage than those detected by both screeners (P = 0.6, not significant). CONCLUSIONS: Independent double reading results in only a modest increase in the detection of cancers and therefore may not be cost effective.

Aged↗
PubMed1995

Measurement of the costs in two mammographic screening programmes in the province of Florence, Italy.

OBJECTIVES: To estimate and to compare the cost per woman examined and per breast cancer detected in two mammographic screening programmes in the province of Florence. SETTING: Two ongoing, population based, mammographic screening programmes in the province of Florence. The first (district project) was started in the seventies in a rural area, whereas the second (city project) was started in the city at the end of 1990. METHODS: All relevant resources consumed by the programmes (costs) were listed and measured. The costs are related to 1993. The unit cost for each phase (recruitment, screening, assessment) of the screening process was estimated by dividing the total cost of the phase by the number of women examined. The cost per cancer detected was obtained by dividing the total cost of the programme by the number of cancers detected at screening. RESULTS: The costs per woman examined were $38.1 and $41.1 in the district and city programmes respectively. The cost per breast cancer detected was $7424 in the district programme and $5180 in the city programme. Staff accounted for more than 50% of the total cost. The unit cost in the screening phase was higher in the district programme, whereas it was lower in the assessment phase. CONCLUSIONS: Our results are consistent with, although slightly lower than, published estimates of the cost per woman screened. Important parameters for determining the efficiency of a mammographic screening programme are the compliance rate and the recall rate.

Breast Neoplasms↗
PubMed1995

Onset of clinical signs in children with HIV-1 perinatal infection. Italian Register for HIV Infection in Children.

OBJECTIVE: To investigate the timing of onset of each clinical sign in infants and children with HIV-1 perinatal infection. DESIGN AND METHODS: A total of 200 HIV-1-infected children followed-up from birth were studied. Failure and conditional probabilities were estimated by the Kaplan-Meier product-limit method. Cox proportional hazard analysis was used to evaluate independently associated factors. Results of 934 seroreverters were used to calculate reference values of CD4+ cell counts and predictivity of early signs. RESULTS: Median age at the onset of any sign was 5.2 months (range, 0.03-56 months). The probability of remaining asymptomatic was 19% [95% confidence interval (CI), 14-25.1] at 12 months and 6.1% (95% CI, 2.6-11.7) at 5 years. Lymphadenopathy (69.5%), splenomegaly (62.4%) and hepatomegaly (58.4%) were the most common signs in the first year of life. Peculiar to the first year of life (compared with subsequent ages) was the onset of primary HIV-1 hepatitis and diarrhoea (rate ratios, 23.3 and 15.2, respectively). When CD4+ cell counts in the asymptomatic stage (age, 2 months; range, 0.03-5.9 months) were below rather than above the fifth percentile in seroreverters, onset of signs was earlier [3 range, 0.03-19) versus 5 (range, 0.03-56) months]. Children manifesting signs before the 5.2-month breakpoint had a lower survival rate [74% (range, 65.9-82%) at 12 months and 45% (range, 32.9-57%) at 5 years] than children manifesting signs later [98% (range, 92.2-100%) at 12 months and 74% (range, 60.3-87.7%) at 5 years]. Children whose birthweight was < or = 2400 g had an earlier onset (24 months; range, 1-57 months) of severe conditions than children with higher birthweight (71 months; range, 1-71 months). Development of lymphadenopathy or hepatosplenomegaly within 3 months of life were reliable indicators of infection. CONCLUSIONS: This study describes the sequence of onset of signs in perinatal HIV-1 infection. Infection is shown to progress faster than in adults and in a different manner. Low birthweight, early decreased CD4+ cell counts, and early onset of signs are predictive of rapid progression.

AIDS-Related Complex↗
PubMed1995

[Letter].

Explore the source record for details and available documents.

Environmental Monitoring↗
PubMed1995

[Evaluation of the costs of mammographic screening program in the city of Florence].

This paper investigated differential direct costs determined by the difference between implementation of mammographic screening program for breast cancer detection in the city of Florence (PFD) and the "absence" of the PFD. The involved resources have been identified, quantified and evaluated. The results of the I round (1991/92) of the PFD involve the following different phases: invitations, mass screening, diagnostic assessment. Differential net costs aumonted to 780 million for total cost, and to 53,000 per screened woman. The PFD invited 27,325 women per year; at the I round, the PFD registered an attendance rate of 53.9% and a recall rate of 4.3%, with a total cost of about one thousand million and a cost per screened woman of about L. 64,000. Instead, economic results of alternative "absence" of screening registered a total cost of 170 million and a cost per screened woman of about L. 100,000. Costs for detected cancer amount about to 8.2 million for PFD and 5.7 million for "absence" of the Program. Sensitivity analysis has been performed texting the fundamental parameters of the PFD: attendance rate, recall rate and life time average of the investiments. The sensitivity analysis, performed on the PFD, registered a variation of total cost from 859 million to 1,216 million and a variation of the total cost per woman screened from L. 43,500 to L. 80,000. Sensitivity analysis results highlighted the fundamental role played by women's attendance and by the percentage of women recalled for diagnostic assessment.

Breast Neoplasms↗
PubMed1994

Population-based breast cancer survival. Mammographic screening activities in central Italy.

BACKGROUND: The aim of this study was to evaluate the effect on 5-year survival of patients with invasive breast cancer relative to demographic and clinical variables (age, residence, and disease diffusion) and to early diagnostic procedures performed in the area. METHODS: The observed (Kaplan-Meier method) and relative 5-year survival in 1263 patients with invasive breast cancer in the Province of Florence, Italy, between 1985-1986 (source: Tuscany Cancer Registry) are presented. The results were compared with those of other European areas and of the Surveillance, Epidemiology, and End Results Program. The Cox model is used to evaluate the effects of age at diagnosis (5-year age groups), disease diffusion (localized, regional, distant, unspecified), residence (Municipality of Florence, screening area, other municipalities), and source of diagnosis (Center for the Study and Prevention of Cancer, hospitals) on observed survival. RESULTS: Observed 5-year survival was 68.4% (Kaplan-Meier method) and relative 5-year survival was 75.4%. Relative survival for patients younger than age 35 at diagnosis was high (82.3%); it decreased slowly from 80.5% in the group of patients 35-44 years of age, to 74.0% in those 65-74 years of age, and steeply decreased to 68.1% in those 75 years of age and older. Relative 5-year survival in Florence was lower only than that observed in Switzerland (Geneva) and in the USA (whites). Five-year prognosis was worse in women 70 years of age or older, in advanced stages, in residents of municipalities not involved in the screening program, and in cases diagnosed in hospitals. The gain in survival may be explained partially by lead-time effect and by length bias due to early diagnosis both in self-referred women and in screening-detected cases. In these cases, though, the better prognosis, although attenuated, persisted after adjustment by disease diffusion. CONCLUSIONS: The results suggest that the early diagnosis of breast cancer in self-referred women affects prognosis, at least concerning 5-year survival. Moreover, although lead-time effect and length bias cannot be excluded in this study, screening by personal invitation may reduce the disadvantage in the survival of patients with breast cancer often observed in rural areas.

Adult↗
PubMed1994

Breast cancer early diagnosis experience in Florence: can a self referral policy achieve the results of service screening?

STUDY OBJECTIVE: To assess the impact of a breast clinic on a specific target population and evaluate early diagnosis performance indicators for breast cancer in the presence of a self referral policy. DESIGN: Women living in Florence between 1980 and 1989 who had undergone mammography at a self referral breast clinic were studied. Main outcome measures were the use of mammography in relation to age, symptoms, and the interval between two subsequent tests, and early diagnosis performance indicators were the detection rate (DR), the prevalence/incidence ratio, and the proportion of early detected cancers. Performance indicators were compared with those from formal screening programmes. SETTING: Florence, Italy. PATIENTS: All mammograms performed at the clinic from 1980-89 in 40-69 year old women living in Florence were examined (n = 42,226). Records included the date of birth and of the examination, the reason for testing (asymptomatic/presence of pain/presence of symptoms other than pain), and the TNM classification for breast cancer cases. MAIN RESULTS: The total number of mammograms performed per annum increased by 70% over the decade, but much of this was routine repeat mammography (54.1% in 1989). Rates of first examinations in asymptomatic women increased in the second half of the decade from 17 per 1000 in 1985 to 31 per 1000 in 1989. Mammographic coverage decreased with increasing age from 12.6% in 40-49 year olds to 6.0% in 60-69 years old. Performance indicators of the activity in asymptomatic women were comparable with those expected in service screening. The proportion of not advanced cancers detected in asymptomatic women was 62.3% with a DR of 5.3 per 1000, and the average prevalence/incidence ratio was 2.9. CONCLUSIONS: High quality mammography performed in a breast clinic in self referred asymptomatic women can achieve as good results as a formal invitation screening service. Only a few of these women will benefit, but those who do are likely to be younger (40-49 year old women).

Adult↗