The structural arteriolar changes in diabetes mellitus and essential hypertension. The relative contribution of ageing and high blood pressure

AIM

To evaluate the relative contribution of blood pressure, non-insulin dependent diabetes mellitus and ageing on arteriolar structural changes in essential hypertension and diabetes mellitus.

POPULATION AND METHODS

One hundred subjects, 25 with hypertension (A), 25 with hypertension and diabetes (B), 25 with diabetes (C) and 25 healthy subjects (D). Blood pressure average values, obtained with non-invasive monitoring, and minimal vascular resistance, calculated with strain-gauge plethysmography, were statistically correlated. Multiple regression analysis was performed to assess the contribution of blood pressure and age.

RESULTS

Minimal vascular resistance was higher in A, B and C than in D, and higher in B than in A and C. The coefficient of blood pressure in the multiple regression analysis was significant for all the parameters in A and B but not in C and D; that of age was significant only in A and only for the average values of mean and diastolic blood pressure.

CONCLUSION

Hypertension and diabetes show arteriolar structural changes of similar gravity. Age does play a role in hypertension but a smaller one than that played by blood pressure. In hypertension and diabetes the lack of significance of the contribution of age to the correlation between minimal vascular resistance and pressure could be ascribed to other neurohumoral factors. These factors play a much more important role in diabetes; where neither blood pressure nor age show any correlation with high vascular resistance.

[Analysis of quality of life. Development of an evaluation instrument]

OBJECTIVE

To develop a questionnaire about quality of life (QV) suitable for Intensive Care Unit (ICU) patients.

DESIGN

Two prospective studies by direct interviews; in the first one the questionnaire was answered before and after surgical intervention and in the second during ICU stay and six months after hospital discharge.

SETTING

Surgical ward and surgical-medical ICU.

MATERIALS AND METHODS

Adult, co-operative patients, resident near the hospital, who gave informed consent have been interviewed. The following items of QOL were investigated: residence, physical activity, social life, perceived QV, oral communication and functional limitation, considering age. The last two items were assessed by the interviewer.

RESULTS

Inter-observer reliability on oral communication and functional limitation, assessed by two interviewers in 87 surgical patients, was good (p = 0.68 and p = 0.72 respectively). Validation of the questionnaire in 37 surgical cases showed worsening in all the items, consistent with theoretical prediction. In the 152 ICU consecutively admitted eligible patients, physical activity, social life, functional limitation and global QV (sum of all the investigated items) significantly changed. Residence, perceived QV and oral communication did not change. Internal consistency of the instrument was good (p < 0.05).

CONCLUSIONS

The evaluative instrument studied shows good reliability and validity. The authors suggest a shorter questionnaire could be tested in future investigations.

Biological activity of particle exhaust emissions from light-duty diesel engines

Whole diesel exhaust has been classified recently as a probable carcinogen, and several genotoxicity studies have found particulate exhaust to be clearly mutagenic. Moreover, genotoxicity of diesel particulate is greatly influenced by fuel nature and type of combustion. In order to obtain an effective environmental pollution control, combustion processes using alternative fuels are being analyzed presently. The goal of this study is to determine whether the installation of exhaust after treatment-devices on two light-duty, exhaust gas recirculation (EGR) valve-equipped diesel engines (1930 cc and 2500 cc) can reduce the mutagenicity associated with particles collected during U.S.A. and European driving cycles. Another interesting object was to compare the ability of alternative biodiesel and conventional diesel fuels to reduce the mutagenic activity associated with collected particles from two light duty diesel engines (both 1930 cc) during the European driving cycle. SOF mutagenicity was assayed using the Salmonella/microsome test (TA 98 and TA 100 strains, +/- S9 fraction). In the first part of our study, the highest mutagenicity was revealed by TA98 strain without enzymatic activation, suggesting a direct-acting mutagenicity prevalence in diesel particulate. The 2500 cc engine revealed twofold mutagenic activity compared with the 1930 cc engine (both EGR valve equipped), whereas an opposite result was found in particulate matter amount. The use of a noncatalytic ceramic trap produced a decrease of particle mutagenic activity in the 2500 cc car, whereas an enhancement in the 1930 cc engine was found. The catalytic converter and the electrostatic filter installed on the 2500 cc engine yielded a light particle amount and an SOF mutagenicity decrease. A greater engine stress was obtained using European driving cycles, which caused the strongest mutagenicity/km compared with the U.S.A. cycles. In the second part of the investigation, even though a small number of assays were available, exhaust emission generation by biodiesel fuel seemed to yield a smaller environmental impact than that of the referenced diesel fuel. The results point out the usefulness of mutagenicity testing in the research of both newer, more efficient automotive aftertreatment devices and less polluting fuels.

Immune response prevalence to formaldehyde-human serum albumin molecular adduct in a healthy population

Formaldehyde (F) covalently binds human serum albumin (HSA), giving rise to the molecular adduct, F-HSA, with F as a hapten. Humoral immune response to the adduct provides a biological marker of F exposure. A new indirect competitive enzyme immunoassay (displacement assay) using an in vitro conjugate F-HSA adduct with a 10:1 ratio was developed to titrate serum anti-F-HSA antibodies. 219 healthy subjects were examined using this assay. Examination of the data using multivariate regression analysis revealed a significant association between the F exposure marker and smoking variables in both smokers (p < 0.001) and ex-smokers (p < 0.01). No association was found between F exposure marker values and age, sex, residence, or profession. Except for the fact that the smoking variable subdivided the population into smokers, ex-smokers, and non-smokers, a significant association was found in non-smokers concerning professional exposure (p < 0.03). Results confirm that the Displacement Assay (sensitivity 96% and specificity 71%) is a useful method of evaluating F exposure, especially in large-scale public health monitoring. In order to evaluate the importance of other exposure sources, such as F pollution in indoor and outdoor air, an interesting follow up to our study would be an evaluation of a possible increase of anti-F-HSA immune response in non-smokers.

Prognosis of childhood epilepsy: a community-based study in Copparo, Italy

We performed a community-based study among children and adolescents with idiopathic and cryptogenic epilepsy and onset of the seizures between 0 and 19 years of age on the prognosis of being seizure-free. The study population was recruited during a descriptive investigation in the Local Health Service of Copparo (USL 34), Ferrara, Northern Italy. We included 111 patients (61 males and 50 females). The average length of follow-up was 18.8 years (ranging from 7 to 24 years). The cumulative probability of being in remission was 81.2% at 15 years after onset and the estimated percentage of patients in remission without therapy was 56% for the same time period. At 15 years after the onset of epilepsy, approximately 20% of patients continued to have seizures; nearly 25% continued to take antiepileptic drugs but had been free of seizures for at least 5 years; nearly 56% had been without seizures and free of medication for at least 5 years. Seizure type, gender, age at onset of the illness, epileptic abnormalities on EEG, family history of convulsive disorders, number and frequency of seizures prior to the start of treatment were found not to be helpful as prognostic factors. This community study, carried out on patients without the well known factors that adversely affect prognosis, confirms that the prospect of seizure control and for withdrawal of therapy is (generally) good.

Geographical distribution of benzene in air in northwestern Italy and personal exposure

Benzene is a solvent strictly related to some industrial activities and to automotive emissions. After the reduction in lead content of fuel gasoline, and the consequent decrease in octane number, an increase in benzene and other aromatic hydrocarbons in gasoline occurred. Therefore, an increase in the concentration of these chemicals in the air as primary pollutants and as precursors of photochemical smog could occur in the future. The objectives of this study were to describe the benzene air pollution at three sites in northwestern Italy throughout 1991 and 1994; to examine the relationship between benzene air pollution in indoor, outdoor, and personal air as measured by a group of nonsmoking university students; and to determine the influence of environmental tobacco smoke on the level of benzene exposure in indoor air environments. The results indicate a direct relationship between population density and levels of contamination; an indoor/outdoor ratio of benzene air pollution higher than 1 during day and night; a similar level of personal and indoor air contamination; and a direct relationship between levels of personal exposure to benzene and intensity of exposure to tobacco smoke. Human exposure to airborne benzene has been found to depend principally on indoor air contamination not only in the home but also in many other confined environments.

Binding thermodynamics of 5-HT1A receptor ligands

The thermodynamic parameters delta G degree, delta H degree and delta S degree of the binding equilibrium of 15 ligands (eight agonists and seven antagonists) to the 5-HT1A receptor subtype have been determined by affinity measurements carried out on rat cortex membranes (minus striatum) at six different temperatures (0, 10, 20, 25, 30, 35 degrees C), and by van't Hoff plots. Most of the compounds studied are tryptamine, phenylpiperazine and tetralin derivatives. Affinity constants were measured by saturation experiments for the selective 5-HT1A receptor agonist [3H]8-hydroxy-N,N-dipropyl-2-aminotetralin ([3H]8-OH-DPAT) and by inhibition assays of [3H]8-OH-DPAT binding for the other compounds. Scatchard plots were monophasic in the full range of temperatures, indicating a single class of high affinity binding sites. Van't Hoff plots of all ligands were linear in the temperature range investigated (0-30 degrees C or 0-35 degrees C). 5-Hydroxytryptamine (serotonin) and 5-methoxy-tryptamine (mexamine) displayed a positive slope. Experimental data indicate that for 5-HT1A receptor subtype agonists and antagonists are not thermodynamically discriminated. The results are discussed from a quantitative point of view with the aim of obtaining new details on the nature of the forces driving the 5-HT1A binding at a molecular level.

Binding thermodynamics at A1 and A2A adenosine receptors

Only recently the binding equilibrium of a number of ligands at adenosine A1 and A2a receptors has been analyzed from a thermodynamic point of view. This approach presents the advantage, with respect to usual affinity constant measurements, of a greater capability to give information about the molecular mechanisms underlying the binding process. All available data agree in indicating that, for both A1 and A2a receptors, agonist binding of adenosine derivatives was totally entropy-driven, while xanthine antagonist binding was essentially enthalpy-driven. The differences in thermodynamic behaviour of A1 and A2a agonists and antagonists could be interpreted in terms of a simplified general model of drug-receptor interaction, which accounted for the role played by the ribose moiety and N6-substituents of adenosinic drugs in determining both affinity and intrinsic activity properties. In the frame of this model, measurements of thermodynamic parameters of N6-monosubstituted agonists allowed to hypothesize, for the first time, the existence of partial agonists to adenosine A1 receptors, as now confirmed experimentally. All thermodynamic data concerning the interaction of all ligands studied with A1 and A2a receptors are briefly discussed in terms of the enthalpy-entropy compensation phenomenon which appears to be widely determined by the reorganization of solvent molecules in the binding process.

Thermodynamics of 5-HT3 receptor binding discriminates agonistic from antagonistic behaviour

Thermodynamic parameters delta G degree, delta H degree and delta S degree of the binding equilibrium of eleven ligands (seven agonists and four antagonists) to the serotonin 5-HT3 receptor subtype have been determined by affinity measurements carried out on rat cortex membranes at six different temperatures (0, 10, 20, 25, 30, 35 degrees C) and van't Hoff plots. Affinity constants were obtained from saturation experiments of [3H]endo-N-(9-methyl-9-azabicyclo[3.3.1]non-3-yl)-1-methyl-1-H-indazole- 3- carboxamide ([3H]BRL 43694, a selective 5-HT3 ligand) or by its displacement in inhibition assays for the other compounds. Van't Hoff plots were essentially linear in the temperature range investigated, showing that the delta Cp degree of the binding equilibrium is nearly zero. Thermodynamic parameters are in the range 18 < or = delta H degree < or = 53 kJ mol-1 and 202 < or = delta S degree < or = 320 J K-1 mol-1 for agonists and -16 < or = delta H degree < or = 0 kJ mol-1 and 70 < or = delta S degree < or = 179 J K-1 mol-1 for antagonists indicating that agonistic binding is totally entropy-driven while antagonistic binding is relatively less entropy- and more enthalpy-driven in the -T delta S degree versus delta H degree plot the thermodynamic data are clearly arranged in separate clusters for agonists and antagonists, which, therefore, turn out to be thermodynamically discriminated. Experimental results are discussed according to the following main points: (i) the approximate linearity of the delta H degree versus delta S degree plot in terms of enthalpy-entropy compensation and (ii) the fact that delta Cp degree approximately equal to 0 for practically all membrane receptors at variance with most reactions involving biomacromolecules in solution. Finally, the phenomenon of thermodynamical discrimination is reviewed and found to occur in five distinct membrane receptorial systems.

Involuntary exposure to tobacco smoke in adolescents: urinary cotinine and environmental factors

The relationship between environmental tobacco smoke exposure and urinary cotinine was studied in 434 14-y-old schoolchildren. To estimate the independent contribution of physiological and environmental variables to cotinine concentrations, we conducted a multiple regression analysis of log-transformed cotinine (R(2) = .21, p < .0001). Environmental tobacco smoke exposure was associated with sharing a household with members who smoked. The most profound associations were linked to (a) the smoking habits of the mother (beta = 5.135, p = .0397); (b) the combined smoking habits of the mother and other family members (beta = 8.201, p = .0020); and (c) the total number cigarettes smoked each day by family members in the household (beta = 0.217, p = .0008). Passive smoke exposure of adolescents is a preventable risk that could be reduced by improving ventilation and by increasing the living space available to each family member. Parents should avoid smoking at home in the presence of their children.

The combination of cisplatin, doxorubicin, and mitomycin (PAM) compared with the FAM regimen in treating advanced gastric carcinoma. A phase II randomized trial of the Italian Oncology Group for Clinical Research

BACKGROUND

In a randomized Phase II study, the authors evaluated the activity and toxicity of the new cisplatin, doxorubicin, and mitomycin C (PAM) combination, that includes cisplatin (P) instead of 5-fluorouracil as in the 5-fluorouracil, doxorubicin, and mitomycin C (FAM) combination, in patients with advanced gastric carcinoma. FAM was utilized as a control treatment arm.

METHODS

Fifty eligible patients were assigned to the FAM (5-fluorouracil 600 mg/m2 intravenous (i.v.) on Days 1, 8, 29, 36; doxorubicin 30 mg/m2 i.v. on Days 1 and 29; mitomycin C 10 mg/m2 i.v. on Day 1; every 8 weeks) and 52 to the PAM combination (cisplatin 60 mg/m2 i.v. on Days 1 and 29; doxorubicin 30 mg/m2 i.v. on Days 1 and 29; mitomycin C 10 mg/m2 i.v. on Day 1; every 8 weeks). All eligible patients were included in the evaluation of response, toxicity and survival.

RESULTS

The PAM combination complete response (CR) rate was 8%, and the CR plus partial response (PR) rate was 21% (95% confidence interval [CI] from 10% to 32%). The median time to progression, duration of response, and duration of survival were 15, 26, and 29 weeks, respectively. The FAM combination CR rate was 2% and the CR plus PR rate was 26% (95% CI from 14% to 38%). The median time to progression, duration of response, and duration of survival were 17, 27, and 23 weeks, respectively. Hematologic and nonhematologic toxicity were mild with both regimens.

CONCLUSIONS

This study shows that this new combination, that does not include 5-fluorouracil, is active in patients with advanced gastric carcinoma. Since treatment with 5-fluorouracil alone is still considered the standard according to some authors, the PAM combination may be included among the sequential clinical options before or after treatment with 5-fluorouracil alone.

Cost analysis of long-term feeding by percutaneous endoscopic gastrostomy in cancer patients in an Italian health district

The aim of this study was to evaluate prospectively the cost of long-term feeding by percutaneous endoscopic gastrostomy (PEG). Cost analysis was carried out in 34 head and neck cancer patients, followed from the time of PEG placement to the death or the end of the study. Three main items were considered: (a) PEG placement (on an inpatient basis), subdivided into five subitems: the Freka FK-07 gastrostomy kit, materials and anaesthetic drugs used, antibiotics and antisecretory drugs, gastroscope amortization expenses and staff; (b) nutrition, considering the costs of enteral-feeding products, nutrition container and flexible tube connecting the container to the PEG; (c) patient care, dividing the patients into three groups: outpatients, home-care patients and outpatients shifting to home care during the follow-up. All patients had one medical and two nursing visits/month, and, if necessary, immediate additional access to a physician or nurse. The mean daily cost per patient of long-term feeding via PEG was obtained by adding up the mean daily costs per patient of the three items, and was compared with that of feeding via nasogastric tube, calculated in 11 patients using the same criteria. No procedure-related death nor periprocedural major or minor complications were observed. The 60-day mortality was 3/34. Seventeen patients were always seen on an outpatient basis and 8 were followed by our home-care unit: 9 outpatients shifted to home care during the follow-up. The mean duration of PEG use was 180.5 days (range 47-639). Two wound infections, treated with antibiotics, occurred during the follow-up. The mean daily costs of placement, nutrition and patient care were (Italian Iiras) L 2500, 24 510 and 1880 respectively (Deutschemarks: DM 2.08, 20.42 and 1.56), for a total mean daily cost of L 28,890 (DM 24.06), slightly higher than that of feeding via a nasogastric tube (L 27,340; DM 22.78). On the basis of the improved quality of life, as well as from the economic point of view, PEG can be considered the procedure of choice for enteral feeding of cancer patients, provided that a reasonably long survival can be expected.

The assessment of skeletal maturation

The measurement of skeletal maturity is important for the analysis of growth and growth disorders. Several methods are available for the assessment of skeletal age. They are all based on the recognition of maturity indicators, that is, of changes in the radiographic appearance of hand-wrist bones. The most commonly used methods are the Greulich and Pyle Atlas and the Tanner-Whitehouse (TW2) method. More recently, the FELS method has been described by Roche and coworkers. The assessments made using the Greulich and Pyle Atlas are often very inaccurate, whereas experience with the FELS method is still very limited. At the present time, the TW2 is still the method of choice. It is hoped that the development of a computerized method of assessment will lead to greater accuracy in the determination of skeletal maturity.

Platelet activation and fibrinolysis in large bowel cancer

Four coagulation indices [fibrinopeptide A (FpA), X degradation products (XDPs), platelet factor (PF4), beta-thromboglobulin (beta-TG)] were assessed in 38 patients affected by large bowel cancer at different stages before surgery, 7 and 30 days after it, to evaluate the capacity of such neoplasia to influence coagulation. The reported study showed that (1) FpA levels were elevated in nearly all cases both before and after surgery (thus it is a useful index for the diagnosis of such neoplasia, although its levels are not influenced by the presence of metastases), (2) increased levels of XDPs were found in a significantly (p < 0.05) higher percent of patients 7 days after surgery (no significant differences were observed in relation to the cancer stage), (3) PF4 levels were in the normal range throughout the study, and (4) beta-TG levels were increased throughout the study in a high percentage of cases. It may be inferred that large bowel cancers may affect coagulation in either way(s), by triggering platelet activation and/or fibrinolysis. The most useful index for the diagnosis and follow-up of this neoplasia is FpA, although its levels are unaffected by the presence of metastases. The comprehensive evaluation of the four above-mentioned coagulation indices may give rise to the suspicion of large bowel cancer.

Binding thermodynamics of serotonin to rat-brain 5-HT1A, 5HT2A and 5-HT3 receptors

The thermodynamic parameters delta G degrees, delta H degrees and delta S degrees of the binding equilibrium of serotonin to 5-HT1A, 5-HT2A and 5-HT3 rat-brain membrane receptors have been determined by means of affinity constant measurements at six temperatures in the range 0 -35 degrees C and van't Hoff plots. At variance with 5-HT1A and 5-HT3, the binding at the 5-HT2A receptors is strongly endothermic and entropy-driven. Comparison with the results obtained by other authors on 5-HT2A receptors in rats and humans suggests that the observed differences can be explained by a single amino acid difference in the receptor sequence between these two species.

Updating about reductions of air and blood lead concentrations in Turin, Italy, following reductions in the lead content of gasoline

Considering its well-know toxicity and the chronic human exposure to lead, international law-makers enforced some directives or laws calling for the reduction of lead content of gasoline. All of these legislative acts aimed to reduce health risks for the general population. The aim of this study was to consider the effectiveness of these laws on air lead levels and consequently on blood lead levels in a randomly selected urban Italian population. In particular, these markers were analyzed over the course of several years, corresponding to the periods just before and after enforcements of the reductions of lead in petrol. Data presented point out some considerations: (1) enforcement of legislative measures concerning the reduction of lead in petrol has reduced atmospheric levels of lead. This result demonstrates a major environmental success in primary prevention efforts. (2) This success is clear especially considering that the actual Pb-B levels can be extended to the urbanized populations. Pb-B levels were consistently higher for drinkers, for older adults, and for males. The mean of Pb-B level for the present urbanized population is higher than the U.S. overall population (6.4 vs 3 microgram/dl). This difference can be also explained considering the different historical period of enforcement of the restriction laws.

Impaired glucose tolerance leads to delayed diagnosis of Alström syndrome

OBJECTIVE

To emphasis the need for timely diagnosis of Alström syndrome.

CASE

We report a case of late-detected Alström syndrome in a boy 15 1/2 years of age who was admitted because of poor wound healing and hyperglycemia.

RESULTS

Diagnosis was made and the patient's impaired glucose tolerance improved by diet.

CONCLUSIONS

Regular follow-ups are needed to recognize and possibly prevent late-appearing complications.

Binding thermodynamics of adenosine A2a receptor ligands

The thermodynamic parameters delta G degree, delta H degree, and delta S degree of the binding equilibrium of seven adenosine agonists and five xanthine antagonists binding specifically to adenosine A2a receptors were determined by means of affinity measurements at six different temperatures (0, 10, 20, 25, 30 and 35 degrees) and van't Hoff plots. Affinity constants were measured on rat striatum membranes by saturation experiments for the selective A2a agonist 2-[p-(carboxy-ethyl)-phenethylamino-]5'-(N-ethyl)carboxamidoadenos ine ([3H]CGS 21680) and by inhibition assays of [3H]CGS 21680 binding for all other compounds. Scatchard plots were monophasic in the full range of temperatures, indicating a single class of high affinity binding sites whose receptor density, BMAX, is essentially temperature independent. Van't Hoff plots were linear in the temperature range 0-30 degrees for agonists and 0-35 degrees for antagonists; their thermodynamic parameters fall, respectively, in the ranges 7 < or = delta H degree < or = 50 kJ/mol and 177 < or = delta S degree < or = 278 J K-1 mol-1 and -36 < or = delta H degree < or = -7 kJ/mol and -33 < or = delta S degree < or = 94 J K-1 mol-1, showing that agonist binding is entropy-driven while antagonist binding is enthalpy-driven. The results are compared with those already reported for the binding of the same compounds to rat brain minus striatum adenosine A1 receptors obtained by displacing [3H]CHA as A1 selective radioligand (Borea PA et al., Mol Neuropharmacol 2: 273-281, 1992). The comparison suggests that the two receptors are very similar as far as their binding sites are concerned and possibly philogenetically related. The analysis of thermodynamical data makes it possible to propose an analogical model of drug-receptor interaction which may account for both affinity and intrinsic activity properties.

[Primary lymphoma of the breast. Clinico-pathologic description of a case]

Primary malignant lymphomas of the breast are extremely rare, accounting for only 0.04% to 0.53% of all breast malignancies. Recently a connection between some primary breast lymphomas and mucosa-associated lymphoid tissue (MALT) has been reported identifying an extranodal lymphoma as MALT-type bears some biologic relevance, especially in terms of its spread to other mucosal sites, which sometimes occurs before disseminating into peripheral lymphoid tissue. The Authors report a case of primary breast lymphoma associated with a possible connective disease. Nevertheless the case reported cannot confirm a precise time relationship between malignant lymphomas and autoimmunity, we think that it can be possible.

Benzene, toluene and xylenes in air, geographical distribution in the Piedmont region (Italy) and personal exposure

The objectives of this study were the determination of: (a) benzene (B), toluene (T) and xylene (X) air pollution in three sites of the Piedmont region (north-western Italy), (b) the relationship between BTX pollution in indoor, outdoor and personal air measured for a group of non-smoking university students, (c) the influence of environmental tobacco smoke on the level of BTX exposure for indoor air environments. Results indicate (i) a direct relationship between human density and level of contamination and higher toluene pollution, (ii) an indoor/outdoor ratio of > 1 for all the three aromatics, (iii) a similar level of personal and indoor air contamination. Human exposure to BTX air pollution has been found to depend principally on indoor air contamination, not only on home pollution, but also, probably on many other confined environments.