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Alberti G, Biesuz R, Pesavento M. Determination of the total concentration and speciation of Uranium in natural waters by the Resin Titration method. Microchem J 2007. [DOI: 10.1016/j.microc.2007.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Alberti G, Fernandez NA, Coineau Y. Fine structure of spermiogenesis, spermatozoa and spermatophore of Saxidromus delamarei (Saxidromidae, Actinotrichida, Acari). ARTHROPOD STRUCTURE & DEVELOPMENT 2007; 36:221-231. [PMID: 18089101 DOI: 10.1016/j.asd.2006.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2006] [Accepted: 11/01/2006] [Indexed: 05/25/2023]
Abstract
Ultrastructural details of spermiogenesis, spermatozoa and the spermatophore of the early derived actinedid mite Saxidromus delamarei are described. Spermatids and mature sperm cells are provided with up to four acrosomal complexes and nuclei derivatives (chromatin bodies). Due to this reason, the sperm cells may be classified as synspermia, a sperm type found only in some spiders until now. The acrosomal complex is composed of a remarkably complicated vacuole and filament. Other peculiarities of sperm structure correspond to those found in prostigmatic mites, i.e. penetration of the chromatin body by the acrosomal filament and the presence of peripheral invaginations of the plasmalemma. The sperm cells are covered by a thin secretion layer of probably proteinaceous material. Stalked spermatophores are rather large, but simply structured and contain relatively few sperm cells. The results are discussed taking systematical and behavioural aspects into account. In particular, it is suggested that the peculiar mating behaviour of these mites secures both sperm transfer and first male's sperm priority and that this allowed reduction of sperm numbers.
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Galceran J, Huidobro C, Companys E, Alberti G. AGNES: A technique for determining the concentration of free metal ions. The case of Zn(II) in coastal Mediterranean seawater. Talanta 2007; 71:1795-803. [DOI: 10.1016/j.talanta.2006.08.027] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Revised: 08/04/2006] [Accepted: 08/21/2006] [Indexed: 10/24/2022]
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Stranges S, Turchini S, Alagia M, Alberti G, Contini G, Decleva P, Fronzoni G, Stener M, Zema N, Prosperi T. Valence photoionization dynamics in circular dichroism of chiral free molecules: the methyl-oxirane. J Chem Phys 2007; 122:244303. [PMID: 16035753 DOI: 10.1063/1.1940632] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The dynamical behavior of circular dichroism for valence photoionization processes in pure enantiomers of randomly oriented methyl-oxirane molecules has been studied by circularly polarized synchrotron radiation. Experimental results of the dichroism coefficient obtained for valence photoionization processes as a function of photon energy have been compared with theoretical values predicted by state-of-the-art ab initio density-functional theory. The circular dichroism measured at low electron kinetic energies was as large as 11%. Trends in the experimental dynamical behavior of the dichroism coefficients D(i)(omega) have been observed. Agreement between experimental and theoretical results permits unambiguous identification of the enantiomer and of the individual orbitals.
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Alberti G, Boccali L, Dionigi C, Vivani R, Kalchenko VI, Atamas LI. Preparation and first characterization of a layered γ-zirconium phosphate derivative containing benzo 15-crown-5 groups covalently attached to inorganic layers. Supramol Chem 2006. [DOI: 10.1080/10610279608035187] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Alberti G, Boccali L, Dionigi C, Vivani R, Kalchenko VI. Preparation and First Characterisation of a Pillared γ-Zirconium Phosphate Derivative Containing Dibenzo 18-Crown-6 Groups Covalently Bound to Inorganic Layers. Supramol Chem 2006. [DOI: 10.1080/10610279808034973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Perseghin G, Burska A, Lattuada G, Alberti G, Costantino F, Ragogna F, Oggionni S, Scollo A, Terruzzi I, Luzi L. Increased serum resistin in elite endurance athletes with high insulin sensitivity. Diabetologia 2006; 49:1893-900. [PMID: 16685503 DOI: 10.1007/s00125-006-0267-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2006] [Accepted: 03/12/2006] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Resistin is an adipokine associated with obesity and type 2 diabetes in animal models, but in humans its role remains uncertain. This study was undertaken to test whether serum resistin is related to insulin resistance and markers of low-grade inflammation in elite athletes taken as a model of extreme insulin sensitivity. SUBJECTS MATERIALS AND METHODS: In 23 elite athletes (sprinters, middle-distance and marathon runners) and in 72 sedentary men including lean and obese individuals with NGT, and obese individuals with IGT or new-onset type 2 diabetes, we assessed insulin sensitivity using a whole-body insulin-sensitivity index (WBISI) derived from a 3-h OGTT; energy homeostasis was also assessed by means of indirect calorimetry, along with circulating adipokines and low-grade pro-inflammatory cyto-chemokines. RESULTS Professional athletes had increased WBISIs (p<0.001) and lipid oxidation (p<0.03); they also showed higher serum resistin concentrations (p<0.001), although the pro-inflammatory chemokines were not increased in comparison with the other study groups. Resistin was independently associated only with fasting plasma NEFA. Increased resistin was detected in the middle-distance and marathon runners, but not in the sprinters when compared with the lean, young, sedentary individuals. CONCLUSIONS/INTERPRETATION Serum resistin concentration is increased in elite athletes, providing evidence against the notion that resistin levels reflect insulin resistance in humans, as seen in animal studies. Increased resistin was observed in aerobic-endurance, but not sustained-power athletes and this feature appeared to be independently associated with parameters of fatty acid metabolism.
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D'Agostino G, Alberti G, Biesuz R, Pesavento M. Potentiometric sensor for atrazine based on a molecular imprinted membrane. Biosens Bioelectron 2006; 22:145-52. [PMID: 16815698 DOI: 10.1016/j.bios.2006.05.014] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2006] [Revised: 04/21/2006] [Accepted: 05/04/2006] [Indexed: 11/21/2022]
Abstract
A molecular imprinted polymer (MIP) membrane for atrazine, not containing macropores, was synthesized and implemented in a potentiometric sensor. It is expected to work like a solid ISE (where the specific carrier are the imprinted sites) the specific carrier being the imprinted site. The active ion is the protonated atrazine, positively charged. To form this species the determination is carried out in acidic solution at pH lower than 1.8, in which atrazine is prevalently monoprotonated. At these conditions the membrane potential increases with atrazine concentration over a wide concentration range (3 x 10(-5) to 1 x 10(-3)M). The slope of the function E versus logc is about 25 mV/decade, showing that the atrazine form sorbed on MIP is the biprotonated one. The detection limit is determined by the relatively high concentration of atrazine released by the membrane in the sample solution at the considered conditions. It seems to be independent of the atrazine concentration in the internal solution of the sensor, but it depends on the acidity of the solution. The response time is less than 10s and the sensor can be used for more than 2 months without any divergence.
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Alberti G, Mondani PM, Parodi V. Eruption of supernumerary permanent teeth in a sample of urban primary school population in Genoa, Italy. EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY 2006; 7:89-92. [PMID: 16842030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
AIM The aim of this epidemiological study was to describe the incidence and distribution of hyperdontia in the primary school population in Genoa (Italy) and to check its influence on the development of orthodontic problems in children. The collected data should also help to find out what is the best age range among children to direct a program for early diagnosis and prevention of malocclusion and oral diseases related to hyperdontia. METHODS The participating children (total number 1577, 814 males and 763 females, between 6 and 10 years of age) chosen in 19 public primary schools in Genoa have been examined by the same specialist through year 2004. Erupted permanent teeth, presence, position and form of supernumerary teeth, malocclusion presence and class, presence of orthodontic devices, age and sex have been noted down for each child. RESULTS The global percentage of hyperdontia was 0.38%, more frequent in males (0.49%) than in females (0.26%). The most common kind of supernumerary tooth was mesiodens (83%). A significant increase of hyperdontia prevalence (from 0.64% to 1.06%) was noticed in children 9 years old. The incidence of malocclusion among children presenting hyperdontia was 83.3%, while the global incidence of malocclusion was 40%. An orthodontic treatment had been planned and started for 20% of children presenting malocclusion. CONCLUSION The study has revealed an incidence of hyperdontia much more frequent in males than in females (2:1). The most common site of eruption of supernumerary teeth is maxillary anterior region. Hyperdontia is strictly related with dental malocclusion. The best age range to direct a program of early diagnosis and prevention of malocclusion and hyperdontia is 9 years old children.
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Michalik P, Dallai R, Giusti F, Mercati D, Alberti G. Spermatozoa and spermiogenesis of Holocnemus pluchei (Scopoli, 1763) (Pholcidae, Araneae). Tissue Cell 2005; 37:489-97. [PMID: 16289178 DOI: 10.1016/j.tice.2005.09.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Revised: 09/25/2005] [Accepted: 09/29/2005] [Indexed: 11/21/2022]
Abstract
Until now, the knowledge on pholcid spermatozoa is based on two species, Pholcus phalangioides and, incompletely, Holocnemus pluchei. To complete this knowledge and to reveal more potential phylogenetic characters, we have investigated sperm ultrastructure and spermiogenesis of H. pluchei. We found that the sperm cells of this species are clearly different from those of P. phalangioides with respect to: (1) the lack of specialization in the cylindrical acrosomal vacuole; (2) a nuclear canal which is located in the periphery and not in the center of the nucleus; (3) a more prominent postcentriolar elongation of the nucleus; (4) the presence of "inner microtubules" in the implantation fossa in early and mid-spermatids; (5) the absence of a helical band of nuclear material; (6) the proximal centriole which is not prolonged; (7) the types of secretion in the seminal fluid (only two types in H. pluchei). Similarities in the spermatozoa of both species concern: (1) a large implantation fossa which contains large amounts of glycogen in mature spermatozoa; (2) absence of a centriolar adjunct; (3) an axonemal basis located in the posterior part of the implantation fossa; (4) the formation of the so-called cleistospermia in the vas deferens. Our results strongly support systematic relationships within Pholcidae placing these two species in different subgroups.
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La Torre A, Impellizzeri FM, Rampinini E, Casanova F, Alberti G, Marcora SM. Cardiovascular responses to aerobic step dance sessions with and without appendicular overload. J Sports Med Phys Fitness 2005; 45:264-9. [PMID: 16230975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
AIM Several studies showed that exercise intensity during aerobic step dance can be modified varying stepping rate, bench height and manipulating body mass using hand held or adding loads to the torso. The aim of this study was to determine the cardiovascular responses during aerobic step dance using an overload strategy not yet investigated: appendicular overload. METHODS Ten healthy and moderately trained women (mean+/-SD: age 27+/-3.4 years, height 167.8+/-4.6 cm, body mass 55.7+/-4.7 kg, body mass index 19.8+/-1.6, VO2max44.4+/-6.1 mLxkg-1xmin-1) performed an incremental treadmill test to determine VO2peak, the VO2-heart rate (HR) and rating of perceived exertion (RPE)-HR relationships. Within 1 week from the laboratory test, the subjects performed two identical aerobic step dance routines: one using a track suit with loads placed in pockets close to the legs and arms and another without overload. RESULTS The appendicular overload (10% of body mass) significantly increased the exercise intensity from 84.5% to 89.8% of HRmax corresponding to 68.9% and 78.3% of VO2peak, respectively (P<0.01). Similarly, RPE increased from 12.1 to 15.7 (P<0.001). The estimated VO2 and the caloric expenditure rose from 30.3 to 34.7 mLxkg-1xmin-1 and from 251 to 288 kcal, respectively. CONCLUSION This study shows that the use of appendicular overload significantly increases the energy cost of aerobic step session similarly to other overload strategies already reported in the literature.
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Alberti G, D'Agostino G, Palazzo G, Biesuz R, Pesavento M. Aluminium speciation in natural water by sorption on a complexing resin. J Inorg Biochem 2005; 99:1779-87. [PMID: 16055193 DOI: 10.1016/j.jinorgbio.2005.06.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Revised: 06/14/2005] [Accepted: 06/16/2005] [Indexed: 11/16/2022]
Abstract
Very stable aluminium complexes may be present in natural waters, which can be detected only using appropriate methods. One of them is the resin titration based on the sorption of aluminium on a strongly sorbing resin, Chelex 100. It was here used to detect strong aluminium complexes, and to characterize them by determining their concentration, and the corresponding stability constant. High and low salinity waters were sampled in different sites in the North of Italy. In all the samples aluminium complexes with high stability constant, up to 10(17.4) M(-1) in the less acidic solution, were detected. The stability constant depends mainly on the solution acidity, increasing with increasing pH up to 7. The concentration of the ligands responsible for the strong complexation is similar to that of aluminium (from 0.5 to 1.5 microM), or somewhat lower in the case of estuarine and sea waters. A small fraction of aluminium (from 0% to 2%) in freshwaters, higher in estuarine and sea waters (14% and 10%, respectively), is present in weakly bound forms which could also be the hydrolysis products. The conditional constants of the strong complexes were determined for the different samples examined. They were found to be slightly lower in the case of the high salinity waters, in which a value of 10(16.1) M(-1) at pH 7.5 was obtained. This is probably due to the higher ionic strength in marine water, which strongly influences the complexation of trivalent metal ions, as seen for example also in the hydrolysis. It could be deduced that similar substances, but at different concentration, would be responsible for the aluminium complexation in the sea and freshwaters here examined. They could be natural organics like fulvic substances, or better some particular complexing sites in this substances with very high affinity for aluminium.
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Cavaletti G, Marmiroli P, Alberti G, Michielon G, Tredici G. Sport–related peripheral nerve injuries: part 2. SPORT SCIENCES FOR HEALTH 2005. [DOI: 10.1007/s11332-2005-004-0012-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Michalik P, Dallai R, Giusti F, Alberti G. The ultrastructure of the peculiar synspermia of some Dysderidae (Araneae, Arachnida). Tissue Cell 2004; 36:447-60. [PMID: 15533460 DOI: 10.1016/j.tice.2004.08.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2004] [Revised: 07/28/2004] [Accepted: 08/09/2004] [Indexed: 11/17/2022]
Abstract
The present study reports on the ultrastructure features of spermatozoa and spermatogenesis of several species of Dysderidae (Dysdera crocata, Dysdera erythrina, Dysdera ninnii, Harpactea arguta, Harpactea piligera, Dasumia taeniifera). Dysderid spiders are known to possess a peculiar sperm transfer form known as synspermia, characterized by fused spermatozoa surrounded by a secreted sheath. Until now the exact mode of formation of the synspermia is unknown. The present study demonstrates that the spermatids are connected via narrow cell bridges during the entire spermiogenesis as is usual, although in Dysderidae they do not separate at end of the spermiogenesis. Instead, they fuse completely within the testes shortly after the spermatid has coiled to get a spherical shape. The number of fusing sperm cells is different in the different observed species. The species of the genus Harpactea thus have synspermia consisting of two fused spermatozoa; whereas in the species of the genus Dysdera four sperm cells are fused and in D. taeniifera at least three spermatozoa are fused. In contrast with other known families with this peculiar form transfer of sperm, the synspermia in Dysderidae are mainly characterized by a conspicuous vesicular area which extends through the entire synspermium surrounding the cell organelles. Thus, all main cell components (e.g., nucleus, acrosomal vacuole, and axoneme) are covered by the vesicular membrane. The vesicular area seems to be functional and probably it is important during sperm activation in female genital system. Simultaneously to the extension of the vesicular area, the synspermium accumulates large amounts of glycogen. The glycogen is mainly located around the centriolar adjunct and along the axoneme accompanying the postcentriolar elongation of the nucleus. A further peculiar feature is the extremely elongated acrosomal vacuole, which seems to be synapomorphic trait for sperm cells of dysderids. Interestingly, spermatogenesis, including the fusion, exclusively occurs within the testes (in contrast to the formation of coenospermia). In the vas deferens only synspermia were found. The secreted sheath surrounding the spermatozoa is finally synthesized in the parts of the vasa deferentia, which are close to the genital opening where numerous vacuoles and microvilli are seen in the epithelial cells.
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Michalik P, Haupt J, Alberti G. On the occurrence of coenospermia in mesothelid spiders (Araneae: Heptathelidae). ARTHROPOD STRUCTURE & DEVELOPMENT 2004; 33:173-181. [PMID: 18089032 DOI: 10.1016/j.asd.2004.02.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2004] [Accepted: 02/02/2004] [Indexed: 05/25/2023]
Abstract
Two species of the early derivative spider family Heptathelidae (Heptathela kimurai yanbaruensis and Ryuthela nishihirai nishihirai) have been investigated with respect to spermiogenesis, focussing on late events during which peculiar transfer forms are developed. It is shown, for the first time in detail, that these spiders produce coenospermia. The coenospermia of these species are large aggregates containing more than 20 individual encapsulated spermatozoa. The coenospermia possess a likely flexible envelope formed by a thick multilayered secretion, which protects the spermatozoa during transfer to the female genital system and storage in the receptacula. In addition, a short description of the main cell components of the individual spermatozoa is given as a complement to previous studies. With the observation presented here, the suggestion that coenospermia are an ancestral character in the Araneae is further confirmed, and plesiomorphic features of spider sperms are consolidated.
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Michalik P, Gray MR, Alberti G. Ultrastructural observations of spermatozoa and spermiogenesis in Wandella orana Gray, 1994 (Araneae: Filistatidae) with notes on their phylogenetic implications. Tissue Cell 2003; 35:325-37. [PMID: 14517100 DOI: 10.1016/s0040-8166(03)00054-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Spermatozoa and spermiogenesis of the prithine filistatid spider Wandella orana are described. The spider produces coenospermia, i.e. sperm aggregations that include several single sperm cells commonly surrounded by a secretion sheath. One sectioned coenospermium in W. orana contains at least five spermatozoa. During copulation many coenospermia are transferred into the female. Coenospermia are regarded as a peculiar transfer form of sperm which occurs in early derivative spiders such as Liphistiomorphae and Mygalomorphae. The only exception which was found in Araneomorphae until now was the filistatine spider Filistata insidiatrix. Our observation is the second case and supports the view that Filistatidae represent an early derivative taxon. Furthermore, the individual sperm cells show characteristics which also may be regarded as being plesiomorphic. There is a cone-shaped acrosomal vacuole, a very long acrosomal filament, a rather stout nucleus and a small implantation fossa. The axoneme shows the 9x2+3 pattern of microtubules which is synapomorphic in Megoperculata (Uropygi, Amblypygi and Araneae). The finding of coenospermia in two distant taxa of Filistatidae may have consequences for phylogenetic and systematic considerations.
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Pesavento M, Biesuz R, Alberti G. Determination of the metal complexation capacity of natural waters by ligand titration in the presence of complexing resins. ACTA ACUST UNITED AC 2003. [DOI: 10.1051/jp4:20030478] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Alberti G, Meyer-Rochow VB. Ultrastructural investigations of testes and spermiogenesis in two species of halacarid mites (Halacaridae, Actinedida, Actinotrichida): Thalassarachna basteri from the Baltic Sea and Halacarellus thomasi from McMurdo Sound (Antarctica). ARTHROPOD STRUCTURE & DEVELOPMENT 2002; 30:315-328. [PMID: 18088964 DOI: 10.1016/s1467-8039(02)00008-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2001] [Accepted: 12/03/2001] [Indexed: 05/25/2023]
Abstract
Testes and sperm cells of two species of halacarid mites, Thalassarachna basteri from the Baltic Sea and Halacarellus thomasi from McMurdo Sound (Antarctica), were investigated. Testes are paired structures, composed of a glandular and a germinal part. The testicular lumen is filled with a very complex secretion that contributes to sperm cell aggregates. Early spermatids of T. basteri display unusual chromatin condensation within the nucleus, but the formation of an acrosomal complex with a small acrosomal vesicle and a long acrosomal filament can be regarded as typical for the group. Tubular invaginations of the plasmalemma occur at the cell periphery. A deep, ring-like infold divides the cell into one part containing the chromatin body and another containing mainly the invaginations and the acrosomal complex. The mature sperm cell is ovoid, aflagellate and surrounded by a distinct secretion sheath. In H. thomasi only a limited number of spermiogenesis stages were observable. Chromatin condensation was rather similar and peripheral invaginations also occurred. However, no acrosomal complex was observed in the early stages. The division of the mature sperm cells into two halves was even more pronounced in H. thomasi, since one half of the cell contained masses of convoluted structures. The same half also contained a structure that remotely resembled an acrosomal complex. The observed differences between T. basteri and H. thomasi sperms support the placing of the two halacarids in separate genera.
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Alberti G, Casciola M, Vivani R, Biswas RK. Preparation and characterization of zirconium phosphate phosphonates, ZrPO4(H2PO4)1-x(RPO2OH)x.nH2O, with .gamma.-layer structure (R = CH3, C3H7, C6H11). Inorg Chem 2002. [DOI: 10.1021/ic00073a022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Alberti G, Griffiths S, Hall D, Hakesley-Brown R, Cox J. Open letter: health professions on the aftermath of terrorism. West J Med 2001. [DOI: 10.1136/bmj.323.7319.1004a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Alberti G, Griffiths S, Hall D, Hakesley-Brown R, Cox J. Open letter: health professions on the aftermath of terrorism. BMJ (CLINICAL RESEARCH ED.) 2001; 323:1004. [PMID: 11679398 PMCID: PMC1121480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Alberti G, Griffiths S, Hall D, Hakesley-Brown R. Testing times for nurses everywhere. NURSING TIMES 2001; 97:19. [PMID: 11966074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Keighley B, Alberti G, Chicholm J, Fradd S, Jackson B, MacSween R, Meldrum H, Pickersgil D, Pringle M. GMC: approaching the abyss. Preservation is well worth the effort. BMJ (CLINICAL RESEARCH ED.) 2001; 322:1599. [PMID: 11458891 PMCID: PMC1120633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Alberti G, Casciola M, Massinelli L, Bauer B. Polymeric proton conducting membranes for medium temperature fuel cells (110–160°C). J Memb Sci 2001. [DOI: 10.1016/s0376-7388(00)00635-9] [Citation(s) in RCA: 507] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Di Palma A, Alberti G. Fine structure of the female genital system in phytoseiid mites with remarks on egg nutrimentary development, sperm-access system, sperm transfer, and capacitation (Acari, Gamasida, Phytoseiidae). EXPERIMENTAL & APPLIED ACAROLOGY 2001; 25:525-591. [PMID: 11989482 DOI: 10.1023/a:1014741808835] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The fine structure of the female genital system is described in two phytoseiid species: Phytoseiulus persimilis Athias-Henriot (mating females) and Typhlodromus rhenanoides Athias-Henriot (overwintering females). The female genital tract is composed of an unpaired gonad, the uterus (oviduct I), and the vaginal duct (oviduct II). The latter leads to the vagina (genital atrium), into which a pair of vaginal glands opens. The gonad (ovary s.l.) has two components: the ovary (s.str) where germ cells develop and the lyrate organ serving as a nutrimentary compartment. In the ovary (s.str.), somacells and germ cells are observed. The germ cells surround a central tissue, to which they have direct contact with a nutritive cord at least in the previtellogenic phase during oogenesis. In fertilized females, cells likely representing capacitated sperm cells are also found in the ovary. The lyrate organ has two arms that extend anteriorly but join in their posterior part in front of the ovary (s.str.). The lyrate organ is composed of a somatic (supporting) and a nutritive tissue. The nutritive tissue, which is a syncytium, is continuous with the central tissue. The uterus starts from the ventral region of the central tissue. Finally, the ultrastructure of the sperm-access system, composed of paired solenostomes, major and minor ducts, emboli, calyces, and vesicles, is reported and functional aspects are discussed. The minor ducts end in the somatic tissue of the ovary s.str. However, because of its extremely reduced lumen and the peculiar morphology of its beginning, it seems unlikely that the minor duct lumen serves as a simple route for the sperm towards the ovary.
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Alberti G. Noncommunicable diseases: tomorrow's pandemics. Bull World Health Organ 2001; 79:907. [PMID: 11693971 PMCID: PMC2566675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
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78
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Senette C, Meloni S, Alberti G, Melis P. Effects of fire on the state of several elements in some soils of Sardinia. ANNALI DI CHIMICA 2000; 90:733-40. [PMID: 11218261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
In order to individuate the modifications induced in the soil by fires relatively to the mobility of metals and rare earth three soils of Sardinia which differ in their mineralogical and physico-chemical characteristics were sampled. The analytical results obtained on the samples drawn at different depths (0-5 and 10-30 cm) three months after a fire and on the tests indicate that only the surface layer underwent significant modifications. The dynamics of metals and the distribution of the rare earths were found to depend, besides the amount and quality of the burned material, on the different behaviour of elements towards leaching. The diffractometric analysis showed that the soil surface layer of all the samples did not exceed 400 degrees C.
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79
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Alberti G, Gegner A, Witaliñski W. Fine structure of the spermatophore and spermatozoa in inseminated females of Pergamasus mites (Acari: Gamasida: Pergamasidae). J Morphol 2000; 245:1-18. [PMID: 10861828 DOI: 10.1002/1097-4687(200007)245:1<1::aid-jmor1>3.0.co;2-a] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This study describes the spermatophore of Pergamasus mites after transfer into the female endogynial sac and modifications of the structure of the female-penetrating spermatozoa. The spermatophore is saccular and contains largely unmodified spermatozoa and variously structured secretions. The spermatozoa that leave the spermatophore reach the inner (proximal) end of the vaginal duct where they presumably escape from the genital tract to continue their route through the hemocoel into the ovarian tissue where fertilization occurs. During this transit, the structure of such spermatozoa changes considerably, in particular when in contact with the ovary. These alterations include modifications of the cell periphery and of certain inclusion bodies. Furthermore, the spermatozoa form protrusions that fit into corresponding invaginations of the somatic tissue of the ovary.
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80
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Petrie J, MacKay C, Alberti G, Williams B. Funding of long term care for older people needs to be publicly debated. BMJ (CLINICAL RESEARCH ED.) 2000; 320:936. [PMID: 10742012 PMCID: PMC1117847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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81
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Alberti G. A desktop guide to Type 2 diabetes mellitus. European Diabetes Policy Group 1998-1999 International Diabetes Federation European Region. Exp Clin Endocrinol Diabetes 1999; 107:390-420. [PMID: 10595591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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82
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Alberti G, Brunet E, Dionigi C, Juanes O, Rodríguez-Ubis JC, Vivani R. Shaping Solid-State Supramolecular Cavities: Chemically Induced Accordionlike Movement of gamma-Zirconium Phosphate Containing Polyethylenoxide Pillars. Angew Chem Int Ed Engl 1999; 38:3351-3353. [PMID: 10602191 DOI: 10.1002/(sici)1521-3773(19991115)38:22<3351::aid-anie3351>3.0.co;2-v] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The hydrophilic oxygen atoms of polyethylenoxide chains inserted as pillars in gamma-zirconium phosphate form hydrogen bonds with the acid groups of the host. As a result the pillars are almost perpendicular to the gamma layers. Upon changing the pH level of the supernatant solution the hydrogen bonds are broken and the pillars become almost perpendicular to the layers (shown schematically). Thus there is a reversible enlargement-shortening of the interlayer space.
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83
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Alberti H, Alberti G. Maybe the time has come for the primacy of the patient in the NHS. BMJ (CLINICAL RESEARCH ED.) 1999; 318:1700. [PMID: 10373191 PMCID: PMC1116041 DOI: 10.1136/bmj.318.7199.1700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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84
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Angius A, Pisano M, Sanca A, Casu G, Persico I, Pitzalis S, De Gioia E, Grignolo FM, Loi A, Sole G, Cao A, Spinelli P, Ghillotti G, Bonomi L, Fossarello M, Serra A, Gandolfi S, Alberti G, Maraini G, Serru A, Orzalesi N, Pirastu M. Molecular basis of open-angle glaucoma in Italy. ACTA OPHTHALMOLOGICA SCANDINAVICA. SUPPLEMENT 1999:16-7. [PMID: 9972327 DOI: 10.1111/j.1600-0420.1998.tb00865.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Glaucoma is a group of ocular diseases characterized by an optic neuropathy in which degeneration of retinal ganglion cells leads to a characteristic excavation of the optic nerve head. Primary open-angle glaucoma (POAG) can be subdivided into two groups according to age of onset:- 1. the more common middle- to late-age onset, chronic open-angle glaucoma (COAG) diagnosed after the age of 40 years; 2. the rarer juvenile open-angle glaucoma (JOAG), which is diagnosed between the age of 3 years and early adulthood. Recently, the gene coding for the trabecular meshwork-induced glucocorticoid response protein (TIGR), located in chromosome 1 (1q23-25), was found mutated in patients affected by POAG. In this work we describe the clinical and molecular genetic features of several Italian families affected by autosomal dominant POAG, collected in various regions of Italy.
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Alberti G, Vivani R, Murcia Mascarós S. First structural determination of layered and pillared organic derivatives of γ-zirconium phosphate by X-ray powder diffraction data. J Mol Struct 1998. [DOI: 10.1016/s0022-2860(98)00472-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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86
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Alberti G, Giontella E, Murcia-Mascarós S, Vivani R. Mechanism of the Topotactic Formation of gamma-Zirconium Phosphate Covalently Pillared with Diphosphonate Groups. Inorg Chem 1998; 37:4672-4676. [PMID: 11670620 DOI: 10.1021/ic980400b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The topotactic reaction of gamma-ZrPO(4)[O(2)P(OH)(2)].2H(2)O (gamma-ZrP) with benzenediphosphonic acid was examined in water and in acetone-water mixtures. This reaction was found to take place in water only on the external surface of the microcrystals, and pillared compounds were never obtained, even after very long reaction times. On the contrary, covalently pillared compounds were quickly obtained in acetone-water mixtures. The mechanism of the latter topotactic reaction was investigated by determining the rate of the phosphate groups released and the rate of the benzenediphosphonates taken up by gamma-ZrP over a long time (50 days). These data showed that pillared derivatives of gamma-ZrP can be obtained because colloidal dispersions of exfoliated lamellae are formed in acetone-water mixtures. The diphosphonate group acts initially as a monovalent species, replacing only one dihydrogen phosphate group on the surface of the exfoliated gamma-lamellae. The colloidal and partially derivatized lamellae thus formed can interact with each other by forming polylamellar pillared systems. When the number of pillared lamellae exceeds a given value (usually 5-6), flocculation of the colloidal gamma-ZrP takes place. Topotactic reactions between packets of pillared lamellae may also continue in the flocculated system. Therefore, the average number of the pillared lamellae slowly increases over time.
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Alberti G, Murcia-Mascarós S, Vivani R. Pillared Derivatives of γ-Zirconium Phosphate Containing Nonrigid Alkyl Chain Pillars. J Am Chem Soc 1998. [DOI: 10.1021/ja981565m] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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88
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Zimmet P, Alberti G, de Courten MP. New classification and criteria for diabetes: moving the goalposts closer. Med J Aust 1998; 168:593-4. [PMID: 9673619 DOI: 10.5694/j.1326-5377.1998.tb141443.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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89
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Unwin N, Alberti G, Aspray T, Edwards R, Mbanya JC, Sobngwi E, Mugusi F, Rashid S, Setel P, Whiting D. Economic globalisation and its effect on health. Some diseases could be eradicated for the cost of a couple of fighter planes. BMJ (CLINICAL RESEARCH ED.) 1998; 316:1401-2. [PMID: 9572743 PMCID: PMC1113110 DOI: 10.1136/bmj.316.7142.1401] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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90
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Alberti G, Giontella E, Murcia-Mascarós S. Mechanism of the Formation of Organic Derivatives of gamma-Zirconium Phosphate by Topotactic Reactions with Phosphonic Acids in Water and Water-Acetone Media. Inorg Chem 1997; 36:2844-2849. [PMID: 11669920 DOI: 10.1021/ic970048m] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The rates of the topotactic reactions between gamma-zirconium phosphate and phenylphosphonic acid in water and water-acetone mixtures at various temperatures were investigated. The slow rates of the process in aqueous medium or in water-acetone mixtures at temperatures lower than 50 degrees C were attributed to a slow interdiffusion of O(2)P(OH)(2)(-) and O(2)P(OH)(C(6)H(5))(-) groups in the interlayer region of gamma-ZrP. Similar to ion-exchange processes, the replacement begins in the external part of the interlayer region and progresses toward the central region with the formation of an advancing phase boundary. In water-acetone mixtures at temperatures higher than 60 degrees C an exfoliation of gamma-ZrP was found. Thus, the initial process is very fast since the substitution can take place directly on the surface of the exfoliated gamma-lamellae. However, after a certain degree of substitution, a flocculation of the colloidal dispersion, which slows down the rate of the further topotactic substitution, was observed. Some considerations on the topotactic substitution occurring on the surface of the exfoliated lamellae and on the mechanism of the diffusion of the exchanging species in the interlayer region are also reported.
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91
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Zanger M, Gräff S, Braunbeck T, Alberti G, Köhler HR. Detection and induction of cytochrome P450IA (CYP 1A)-like proteins in Julus scandinavius (Diplopoda) and Oniscus asellus (Isopoda): a first analysis. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1997; 58:511-517. [PMID: 9060366 DOI: 10.1007/s001289900364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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92
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Zimmet P, Hodge A, Nicolson M, Staten M, de Courten M, Moore J, Morawiecki A, Lubina J, Collier G, Alberti G, Dowse G. Serum leptin concentration, obesity, and insulin resistance in Western Samoans: cross sectional study. BMJ (CLINICAL RESEARCH ED.) 1996; 313:965-9. [PMID: 8892415 PMCID: PMC2352310 DOI: 10.1136/bmj.313.7063.965] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To measure serum leptin concentrations in the Polynesian population of Western Samoa and to examine epidemiological associations of leptin with anthropometric, demographic, behavioural, and metabolic factors in this population with a high prevalence of obesity and non-insulin dependent diabetes mellitus. DESIGN Cross sectional study, leptin concentration being measured in a subgroup of a population based sample. SUBJECTS 240 Polynesian men and women aged 28-74 years were selected to cover the full range of age, body mass index, and glucose tolerance. MAIN OUTCOME MEASUREMENTS Serum leptin, insulin, and glucose concentrations; anthropometric measures; physical activity; and area of residence. RESULTS Leptin concentrations were correlated with body mass index (r = 0.80 in men, 0.79 in women) and waist circumference (r = 0.82 in men, 0.78 in women) but less so with waist to hip ratio. At any body mass index, leptin concentration was higher in women than men (geometric mean adjusted for body mass index 15.3 v 3.6 pg/l, P < 0.001). Leptin concentration also correlated with fasting insulin concentration (r = 0.63 in men, 0.64 in women) and insulin concentration 2 hours after a glucose load (r = 0.58 in men, 0.52 in women). These associations remained significant after controlling for body mass index; effects of physical activity and of rural or urban living on leptin concentration were eliminated after adjusting for obesity, except values remained high in urban men. 78% of variance in leptin was explained by a model including fasting insulin concentration, sex, body mass index, and a body mass index by sex interaction term. Similar results were obtained if waist circumference replaced body mass index. CONCLUSIONS The strong relation of leptin with obesity is consistent with leptin production being proportional of mass to adipose tissue. The relation with insulin independent of body mass index suggests a possible role for leptin in insulin resistance or hyperinsulinaemia.
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Mandò M, Margiacchi GP, Alioto R, Ferri L, Bernardoni F, Alberti G, Teti A, Simone LD, Bardelli M. [Introduction of definite molecular weight heparan sulfate in a protocol of prevention of deep venous thrombosis in prosthetic orthopedic surgery]. Minerva Cardioangiol 1996; 44:457-60. [PMID: 8999370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Use of definite molecular weight heparan sulphate in a protocol for the prevention of deep venous thrombosis in the total joint replacement surgery. The authors propose a working protocol for the prevention of deep venous thrombosis in prosthetic orthopaedic surgery. It requires that integration of pharmacological, anaesthesiological, rheological and physiokinesitherapic measures, it has permitted a very good prevention of thromboembolic disease and it is well-tolerated and safe. The protocol requires: peripheral anaesthesia (sub-arachnoidal block), pre and post-operative pharmacological treatment with heparan-sulphate of a fixed molecular weight, haemodilution with maintenance of the haematocrit at no more than 30%, early physiokinesitherapy associated with the use of elastic stockings graduated tension. The fifty patients treated with this protocol were controlled during the pre-operative and post-operative stage and one month later and no thrombo-embolic complications resulted.
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Alberti G, Oguni M, Podgor M, Sperduto RD, Tomarev S, Grassi C, Williams S, Kaiser-Kupfer M, Maraini G, Hejtmancik JF. Glutathione S-transferase M1 genotype and age-related cataracts. Lack of association in an Italian population. Invest Ophthalmol Vis Sci 1996; 37:1167-73. [PMID: 8631631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
PURPOSE To investigate possible associations between the gene number and allelic forms of glutathione S-transferase M1 (GSTM1) and the occurrence of nucleic and cortical age-related cataracts. METHODS Patients with cortical cataract, nuclear cataract, mixed and cortical cataract, and no cataract were sytematically selected from subjects evaluated in the Italian-American Study of the Natural History of Age-Related Cataract. The patients were typed for the A, B, and null alleles of GSTM1 using a variation of the amplification refractory mutation system. RESULTS Forty-nine percent of patients (50/102) with cortical cataracts, 45% (13/29) with nuclear cataracts, 51% (36/71) with mixed nuclear and cortical cataracts, and 50% of controls (49/98) were homozygous for the null GSTM1 allele. Twenty-five percent of patients (26/102) with cortical cataracts, 24% (7/29) with nuclear cataracts, 31% with mixed nuclear and cortical cataracts, and 27% of controls (26/98) displayed only the A allele for GSTM1. Twenty-four percent of patients (24/102) with cortical cataract, 24% (7/29) with nuclear cataracts, 14% (10/71) with mixed nuclear and cortical cataract, and 18% of controls showed only the B allele for GSTM1. Two percent of patients (2/102) with cortical cataracts, 7% (2/29) with nuclear cataracts, 4% (3/71) with mixed nuclear and cortical cataracts, and 5% of controls (5/98) showed both A and B alleles for GSTM1. CONCLUSIONS No associations between the GSTM1 alleles, including the null allele, and cataracts were detected in this study.
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95
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Zanger M, Alberti G, Kuhn M, K�hler HR. The stress-70 protein family in diplopods: induction and characterization. J Comp Physiol B 1996. [DOI: 10.1007/bf00301130] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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96
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Alberti G, Costantino U, Dionigi C, Murcia-Mascarós S, Vivani R. Layered and pillared zirconium phosphate-phosphonates and their inclusion chemistry. Supramol Chem 1995. [DOI: 10.1080/10610279508032517] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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97
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Köhler HR, Wein C, Reiss S, Storch V, Alberti G. Impact of heavy metals on mass and energy flux within the decomposition process in deciduous forests. ECOTOXICOLOGY (LONDON, ENGLAND) 1995; 4:114-137. [PMID: 24197619 DOI: 10.1007/bf00122172] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
: Laboratory experiments on microbial decomposition and on the contribution of diplopods to organic matter decomposition in soil were combined with field studies to reveal the major points of heavy metal effects on the leaf litter decomposition process. The study focused on the accumulation of organic litter material in heavy metal-contaminated soils. Microbial decomposition of freshly fallen leaves remained quantitatively unaffected by artificial lead contamination (1000 mg kg(-1)). The same was true for further decomposed leaf litter material, provided that the breakdown of this material was not influenced by faunal components. Although nutrient absorption in diplopods is affected by high lead contents in the food, this effect alone, however, was shown not to be sufficient for the massive deceleration of the decomposition process under heavy metal influence which could not only be observed in the field but occurred in microcosm studies as well. Reduced reproduction and lower activity of the diplopods most likely were responsible for the observation that lead-influenced diplopods enhanced microbial activity in soil only in a lesser degree than uncontaminated animals did. This effect is assigned to represent the main reason for decreased decomposition rates and the subsequent accumulation of organic material in heavy metal-contaminated soils.
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Sanjust E, Rinaldi AC, Rescigno A, Porcu MC, Alberti G, Rinaldi A, Finazzi-Agrò A. A hydroxyquinone with amine oxidase activity: preparation and properties. Biochem Biophys Res Commun 1995; 208:825-34. [PMID: 7695641 DOI: 10.1006/bbrc.1995.1411] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The preparation and some properties of a hydroxyquinone showing an amine oxidase-like activity are described. The compound, 2-hydroxy-5-methyl-1,4-benzoquinone, oxidizes a wide range of primary amines, both benzylic and non-benzylic, at the expenses of molecular oxygen in the presence of Cu2+ ions, and reacts with hydrazine derivatives leading to stable, inactive adducts. This behaviour is similar to that of 2,4,5-trihydroxyphenylalanine quinone-containing amine oxidases and therefore the present compound could be a useful model to understand the reaction mechanism of those enzymes.
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100
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Alberti G, Gandolfi SA, Maraini G. Lens sodium channels are inactivated by anti-MIP26 antibodies. Exp Eye Res 1993; 57:653-8. [PMID: 8150018 DOI: 10.1006/exer.1993.1173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Sodium-specific channels can be functionally identified in phosphatidylcholine liposomes incorporating detergent-solubilized membrane proteins from pig lens epithelium and outer cortex. The transport of sodium is saturable, specific and protease-sensitive. MIP26 was identified in the solubilized membrane fraction and in the liposomes by means of Western blot analysis. Pre-treatment of liposomes with anti-MIP26 antiserum abolished the transport of sodium. These data indicate that MIP26 is associated to a sodium selective transport activity.
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