Showing papers by "University of Siena published in 1989"

A case-control study of gastric cancer and diet in Italy.

Abstract: A case-control study was conducted in high- and low-risk areas of Italy to evaluate reasons for the striking geographic variation in gastric cancer (GC) mortality within the country. Personal interviews with 1,016 histologically confirmed GC cases and 1,159 population controls of similar age and sex revealed that the patients were more often of lower social class and resident in rural areas and more frequently reported a familial history of gastric (but not other) cancer. After adjusting for these effects, case-control differences were found for several dietary variables, assessed by asking about the usual frequency of consumption of 146 food items and beverages. A significant trend of increasing GC risk was found with increasing consumption of traditional soups, meat, salted/dried fish and a combination of cold cuts and seasoned cheeses. The habit of adding salt and the preference for salty foods were associated with elevated GC risk, while more frequently storing foods in the refrigerator, the availability of a freezer and use of frozen foods lowered risk. Reduced GC risk were associated with increasing intake of raw vegetables, fresh fruit and citrus fruits. Lowered risk was also related to consumption of spices, olive oil and garlic. Neither cigarette smoking nor alcoholic beverage drinking were significantly related to GC risk. The case-control differences tended to be consistent across geographic areas, despite marked regional variations in intake levels of certain foods. The high-risk areas tended to show higher consumption of food associated with elevated risk (traditional soups, cold cuts) and lower consumption of foods associated with reduced risks (raw vegetables, citrus fruits, garlic). Our findings indicate that dietary factors contribute to the regional variation of stomach cancer occurrence in Italy, and offer clues for further etiologic and prevention research.

Cytotoxin production by Campylobacter pylori strains isolated from patients with peptic ulcers and from patients with chronic gastritis only.

Abstract: A total of 66.6% of Campylobacter pylori strains isolated from patients with peptic ulcers produced a cytotoxin active against mammalian cells in vitro, versus 30.1% of strains isolated from patients with chronic gastritis of various degrees of severity only. This difference was statistically significant and suggests that the toxic substance could be involved in the development of peptic ulcers.

Protective Effect of Inhaled Furosemide on Allergen-Induced Early and Late Asthmatic Reactions

Abstract: The movement of ions and water across the membranes of bronchial cells is part of the control of the bronchial obstructive response to physical stimuli. In a double-blind, randomized, crossover study, we compared the effect of an aerosol of the loop diuretic furosemide with that of a placebo on the early (within 60 minutes) and late (4 to 12 hours) asthmatic responses to a specific inhaled allergen. We studied 11 subjects with mild allergic asthma, who had both early and late asthmatic responses to a specific inhaled allergen in a preliminary challenge. After placebo administration, the maximal changes (mean +/- SE) from base line in the forced expiratory volume in one second (FEV1) and specific airway resistance were, respectively, a decrease of 35 +/- 4 percent and an increase of 288 +/- 56 percent between 0 and 60 minutes after inhalation of the allergen (early response) and a decrease of 35 +/- 5 percent and an increase of 301 +/- 40 percent between 4 and 12 hours (late response). After furosemide administration (4 ml; 10 mg per milliliter), the early response to inhaled allergen was markedly attenuated in all the subjects, and the late response in all but one. The maximal changes in the FEV1 and specific airway resistance were, respectively, a decrease of 11 +/- 2 percent and an increase of 61 +/- 2 percent between 0 and 60 minutes and a decrease of 20 +/- 4 percent and an increase of 178 +/- 25 percent between 4 and 12 hours (P less than 0.05 for all comparisons). No significant differences were seen in the bronchoconstrictor response to inhaled methacholine after furosemide or placebo administration. We conclude that a furosemide-sensitive mechanism in the airways is involved in the pathogenesis of the reactions of patients with allergic asthma. Whether inhaled furosemide might be useful in the treatment of allergic asthma is uncertain and will require further study.

Peritoneal vascular changes in continuous ambulatory peritoneal dialysis (CAPD): an in vivo model for the study of diabetic microangiopathy.

Abstract: Replication of the basement membrane of the peritoneal capillaries and the mesothelium is observed in all uremic patients after a period of continuous ambulatory peritoneal dialysis (CAPD). Biopsy specimens of the parietal peritoneum were taken in diabetic and non-diabetic patients on insertion or repositioning of the CAPD catheter. The basement membrane of the capillaries and mesothelium was normal in non-diabetics on insertion of the catheter, but after 2 to 66 months of CAPD, multiple replication was found. In nearly all the diabetics there was already replication of the basement membrane of the peritoneal capillaries before CAPD was begun but the basement membrane of the mesothelium was intact. After several months of CAPD thickening of the basement membrane of the capillaries was found in 36% of diabetics, sometimes to the point of occlusion. After CAPD, replication of the basement membrane of the mesothelium has been observed in both diabetics and non-diabetics although it is initially perfectly normal in both. CAPD is proposed as an experimental model for diabetic microangiopathy in man.

Diagnostic specificity of sensory and motor nerve conduction variables in early detection of carpal tunnel syndrome.

Abstract: In the carpal tunnel syndrome (CTS) sensory nerve conduction is more sensitive than motor conduction. However, 8%-25% of the sensory distal latencies in symptomatic hands may still be normal. A systematic study was made of the median, ulnar and radial orthodromic nerve conduction velocities (SNCV) stimulating each of the fingers separately. Four SNCVs from the median nerve, two SNCVs from the ulnar nerve and one from the radial nerve were obtained, and the ratio of the median to radial SNCV and the ratios of the median and ulnar SNCVs were estimated. The significance of these parameters in the diagnosis of the CTS was studied, and a rapid technique for the screening of nerve entrapment in the initial stages of the disease is proposed. Three hundred and seventy-five symptomatic hands were examined. Seventy-five hands showed normal distal latency, in which cases, however, the SNCV of the ring finger was always outside the normal range, while the SNCVs of the thumb, index and middle fingers were abnormal in 64%, 80% and 92% of cases respectively. The amplitudes of the sensory responses were the least sensitive of the parameters studied. Our results suggest that a study of the median nerve digital branch to the ring finger may be of value in providing an easily performed and rapid technique for screening an early median nerve entrapment at the wrist.

Metabolic and clinical effects of ipriflavone in established post-menopausal osteoporosis.

Abstract: Twenty patients with post-menopausal osteoporosis were randomly divided into two groups of ten patients and treated under double-blind conditions with ipriflavone (Osteofix) or placebo. The dosage was 600 mg/day given in three doses and treatment lasted 6 months. All the patients received an oral calcium supply (1 g per day). At baseline and then after 3 and 6 months, the following parameters were controlled: bone mineral content at the lumbar spine, distal radius and femoral shaft; parameters of bone metabolism (alkaline phosphatase, PTH, osteocalcin, calcitonin, calciuria and hydroxyprolinuria); clinical conditions (pain at rest and on movement, motility). Ipriflavone facilitated the conservation of bone mass, that increased in one of the tested areas (distal radius). On the contrary, a bone mineral loss was found in the group treated with placebo, which was significant in the spine. Pain and motility significantly improved in the group treated with ipriflavone; there was an initial improvement in the control group, followed by a sharp worsening. The parameters investigated showed a significant reduction of osteocalcin in the ipriflavone group that indicates a modulation on bone turnover. The drug was well tolerated and compliance to oral treatment was excellent.

Morphogenesis of the decapitated and decaudated sperm defect in two brothers

Abstract: The "decapitated sperm" defect, found in both of two sterile brothers, may be assumed to have a genetic origin. The present material suggests that the term "decapitated spermatozoa" is not exact, because detached heads and tails were found in the brothers' ejaculate that could be regarded as "decapitated tails" and "decaudated heads." The present report describes frequent, more or less advanced stages of detachment. Both heads and tails showed a normal structure in which only the postnuclear region was deficient, lacking basal plate and implantation fossa. A break at a different level of the midpiece, and therefore three kinds of separation, were observed. The defect, according to the present research, must originate in the testicular region, whereas the detachment occurs in the epididymis.

Cytoskeletal changes during generative cell division and sperm formation in Tradescantia virginiana

Abstract: Cytoskeletal organization and chromosome behavior were studied inTradescantia generative cells prior to and during sperm formation using in vitro grown pollen tubes and fluorescence staining methods. Before pollen germination, the crescent-shaped generative cell contains a reticulate microtubule (Mt) system. The cell elongates dramatically after germination, and its Mts assume a helical to longitudinal arrangement. Chromosome condensation is evident approximately 3hr after germination. Kinetochores appear as dark interruptions in the Mt array, and thus seem to attach directly to interphase fibers. No metaphase plate typical of other cells is observed with either DAPI or anti-tubulin staining. Instead, the chromosomes adopt a twisted or braided arrangement, with kinetochores distributed along the length of the cell and kinetochore fibers linked to each other and to surrounding fibers. Anaphase is characterized by a staggered, overlapping separation of chromosomes and by elongation of Mt branches connecting opposing kinetochore fibers. Cytokinesis appears to utilize a furrowing process; a phragmoplast or cell plate was never seen. As a result of these events, the sperm directly inherit their cytoskeleton from generative cell Mts involved in division. No actin fibers are observed at any stage using rhodamine-phalloidin staining. The results are discussed in terms of other reports on sperm formation, possible mitotic and cytokinetic mechanisms, and past distinctions between Mt arrays in higher plant somatic cells.

Determination of metal deposition patterns by epiphytic lichens

Abstract: The use of epiphytic lichens as quantitative monitors of airborne heavy metals needs a standardization of collection, analytical procedures and of data elaboration. Evidence is given of a patterned metal accumulation in lichens and for the foliose species, the analysis of the outermost edge of the thallus is suggested. Moreover, the raw concentrations of metals must be normalized to the earth's crustal abundance, as lichens entrap atmospheric particulates which are mostly constituted by soil and rock dust suspended by wind.

Effects of inducers of drug metabolism on basic hepatic forms of mouse glutathione transferase.

Abstract: The cytosolic glutathione transferases (GSTs) with basic pI values have been studied in mouse liver after treatment with 2,3-t-butylhydroxyanisole (BHA), cafestol palmitate (CAF), phenobarbital (PB), 3-methylcholanthrene (3-MC) and trans-stilbene oxide (t-SBO). The cytosolic GST activity was induced by all compounds except for 3-MC. Three forms of GST were isolated by means of affinity chromatography and f.p.l.c. The examination of protein profiles and enzymic activities with specific substrates showed that the three GSTs correspond to those found in control animals, i.e. GSTs MI, MII and MIII. The class Mu GST MIII accounted for the major effect of induction, whereas the class Alpha GST MI and the class Pi GST MII were unchanged or somewhat down-regulated. The greatest induction was obtained with BHA, PB and CAF. The activities of other glutathione-dependent enzymes were also studied. An increase in glutathione reductase and thioltransferase activities was observed after BHA, PB or CAF treatment; glyoxalase I and Se-dependent glutathione peroxidase were depressed in comparison with the control group in all cases studied.

Epidemiology of hip fractures in Siena, Italy, 1975-1985.

Abstract: A survey of 1567 fractures of the proximal end of the femur due to minor trauma occurring in elderly people was performed. The fracture incidence rate per 100,000 individuals in the population at risk was calculated. Hip fracture prevailed in women with a sex ratio of women to men of 3.81; in both sexes the incidence was more closely related to age than any other factor. The incidence rate of fracture increased significantly in women during the period from 1975 to 1985, whereas there was no significant increase in men during this time. This change may be related to the continuing trend toward a greater proportion of elderly women in the population. The incidence rate in men showed a long-cycle periodic behavior correlated with the long-cycle trend of cloud cover and rainfall; it is possible that precipitation and a greater occurrence of femoral fractures might be interrelated in men. This parallelism was not evident in women. In women the rise in fracture rate was not continuous but decreased periodically. The zeniths of fracture incidence were preceded two years by a decrease in temperature and an increase in cloud cover and rainfall, suggesting a possible relationship between fractures and the diminution of ultraviolet radiation. Language: en

Metal biomonitoring in bird eggs: a critical experiment.

Abstract: Bird eggs have been widely used as an indicator of exposure to persistent contaminants. Recent advances in biomonitoring tend to use multimedia environmental models including wildlife for mass balances of chemicals or in a monitor strategy for food quality. Theoretically the high protein and lipid content of the egg binds both polar and apolar chemicals. High concentrations of lipophilic contaminants and methylmercury have been described in experimental birds and wild species throughout the world but metals such as cadmium and lead have always been found at natural levels even in the eggs of birds heavily exposed to metals. These findings pose the question of the relationship between environmental and egg levels of metals. The existence of a metabolic mechanism preventing the transfer of metals into the eggs would disqualify this as a method of monitoring metals. The air of the present paper is to investigate the capacity of bird eggs to reflect the environmental input of inorganic forms of mercury, cadmium and lead so that the validity of this biological sample in environmental studies can be assessed.

Biotransformation of mercury by bacteria isolated from a river collecting cinnabar mine waters.

Abstract: One hundred six strains of aerobic bacteria were isolated from the Fiora River which drains an area of cinnabar deposits in southern Tuscany, Italy. Thirty-seven of the strains grew on an agar medium containing 10μg/ml Hg (as HgCl2) with all of these strains producing elemental mercury. Seven of the 37 strains also degraded methylmercury. None of 106 sensitive and resistant strains produced detectable monomethylmercury although 15 strains produced a benzene-soluble mercury species. Two strains of alkylmercury (methyl-, ethyl- and phenylmercury) degrading bacteria were tested for the ability to degrade several other analogous organometals and organic compounds, but no activity was detected toward these compounds. Mercury methylation is not a mechanism of Hg resistance in aerobic bacteria from this environment. Growth of bacteria on the agar medium containing 10μg/ml HgCl2 was diagnostic for Hg detoxification based on reduction.

Ultrastructure of the vegetative cell ofBrassica napus pollen with particular reference to microbodies

Abstract: The ultrastructure of the vegetative cell ofBrassica napus tricellular pollen grains, just before anthesis with standard chemical fixation, is reported. The vegetative cell may be regarded as a highly differentiated and metabolically active fat-storage cell. It contains many mitochondria with a well developed internal membrane system, starchless plastids, microbodies, lipid bodies, dictyosomes and numerous vesicles thought to originate from the dictysomes. Rough endoplasmic reticulum organized in stacks of cisternae is also spatially associated with certain organelles, mainly lipid bodies, microbodies and plastids. There are also randomly distributed polyribosome areas. The microbodies are mainly polymorphic in shape and are often observed in contact with lipid bodies. The above spatial relationship implies that the microbodies may have a glyoxysomal function. In the late period of vegetative cell maturation, the microbodies are probably involved in the process of glyconeogenesis in which the conversion of lipid reserves to sugar takes place.

Growing skull fractures: progressive evolution of brain damage and effectiveness of surgical treatment.

Abstract: The growing skull fracture of childhood is a well-known but variously interpreted syndrome. Attempts have been made to find different pathogeneses for clinical and pathological patterns that are really successive phases of a single process, arising from the interaction of three basic conditions: (1) head injury with a large gaping fracture; (2) corresponding dural tear; (3) occurrence nearly always in infancy (the first year of life or period of maximum brain growth). This combination of factors alters the normal distribution of the intracranial pressure vectors and the fracture behaves like a "neosuture" with abnormal growth of the skull on the injured side. Simultaneously, the ventricular system tends to deform, dilating and shifting towards the side of the fracture. Three cases, successfully treated at a very late stage, are described. The good surgical results confirm the validity of the surgical method and its underlying theoretical basis.

Ontogeny of intruding non-periplasmodial tapetum in the wild chicory,Cichorium intybus (Compositae)

Abstract: The tapetal development ofCichorium intybus L. is investigated using LM and TEM and discussed in relation to the development in other species. During the second meiotic division the tapetal cells become binucleate and lose their cell walls. They intrude the loculus at the time of microspore release from the meiotic callose walls, which means that a locular cavity is never present in this species. During pollen development they tightly junct the exine, especially near the tips of the spines. During the two-celled pollen grain stage they degenerate and most of their content turns into pollenkitt. Until anther dehiscence they keep their individuality, which means that these intruding tapetal cells never fuse to form a periplasmodium. The ultrastructural cytoplasmatic changes during this development are discussed in relation to possible functions.