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1.
Plant Physiol Biochem ; 165: 47-56, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34034160

ABSTRACT

Water stress triggers acclimation responses and can damage plants, which varies by species and stress levels. Ongoing climate change is projected to result in longer and more intense water stress conditions leading to an alarming increase in drought-induced forest decline. The aim of this study was to evaluate the physiological responses of leaves and stem wood anatomy from Araucaria araucana pot-grown three-year old seedlings, a conifer tree from northwestern Patagonia. Plants were subjected to moderate and severe water restriction regimes and compared to well-watered controls. Severe water stress reduced relative leaf water content and triggered an accumulation of free proline in leaves, regardless of age. Epicuticular wax extrusions increased in apical leaf stomata while photosynthetic pigments decreased, resulting in differential oxidative damage. The concentration of phenolic compounds was not affected by water restrictions. Plants exposed to restricted water regimes showed diminished middle leaf biomass and expansion (~60% of total leaves), increased stem wood density, and experienced 7% and 30% mortality rates under moderate and severe water stress, respectively. Our findings suggest that under moderate water stress, analogous to short-term droughts, A. araucana seedlings activate physiological mechanisms that allow them to withstand short periods of drought, while more severe water stress and longer droughts can be severely harmful.


Subject(s)
Seedlings , Water , Araucaria araucana , Droughts , Photosynthesis , Plant Leaves , Stress, Physiological
2.
Vox Sang ; 98(3 Pt 1): e295-363, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20432515

ABSTRACT

A critical aspect of blood transfusion is the timely provision of high quality blood products. This task remains a significant challenge for many blood services and blood systems reflecting the difficulty of balancing the recruitment of sufficient donors, the optimal utilization of the donor's gift, the increasing safety related restrictions on blood donation, a growing menu of specialized blood products and an ever-growing imperative to increase the efficiency of blood product provision from a cost perspective. As our industry now faces questions about our standard practices including whether or not the age of blood has a negative impact on recipients, it is timely to take a look at our collective inventory management practices. This International Forum represents an effort to get a snap shot of inventory management practices around the world, and to understand the range of different products provided for patients. In addition to sharing current inventory management practices, this Forum is intended to foster an exchange of ideas around where we see our field moving with respect to various issues including specialty products, new technologies, and reducing recipient risk from blood transfusion products.


Subject(s)
Blood Banks/organization & administration , Inventories, Hospital/organization & administration , Adult , Americas , Asia , Blood Banks/statistics & numerical data , Blood Preservation/methods , Blood Preservation/standards , Blood Preservation/statistics & numerical data , Blood Transfusion/standards , Blood Transfusion/statistics & numerical data , Child , Cryopreservation , Erythrocyte Aging , Europe , Humans , Infant, Newborn , Medical Records , Surveys and Questionnaires , Time Factors
4.
Monaldi Arch Chest Dis ; 63(3): 158-62, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16312206

ABSTRACT

BACKGROUND: Correct identification of individuals with latent tuberculosis infection (LTBI) is a crucial element of the elimination strategy, allowing their adequate treatment. In addition to tuberculin skin test (TST), the Quantiferon test (QFT, based on whole blood gamma-interferon release) had been recently proposed. Aim of the study is to compare this test to TST for identification of LTBI in a non-selected population, in order to verify their value in identifying truly infected individuals (entitled to receive preventive chemotherapy), and to exclude from treatment those having a positive TST for other reasons (e.g. after BCG vaccination). METHODS: 136 consecutive persons (78 males, mean age 34 +/- 9 years) referred to the clinic for TST were recruited (78 born in low--or middle--income countries). Based on their history, the cases were divided into 4 groups: 1) recently traced contacts of whom 18 TST negative and 28 TST positive; 2) 22 screening subjects, all TST negative; 3) BCG vaccinated subjects (14); and 4) 54 subjects already undergoing treatment of LTBI for exposure to TB. RESULTS: The overall agreement between TST and QFT was 72% (64% in TST positive and 88.4% in TST negative subjects). The proportion of TST positive/QFT negative BCG vaccinated individuals was 23.1%. The K coefficient was 0.474 in recently traced contacts, 0.366 in BCG vaccinated individuals and 0.451 overall. CONCLUSIONS: The study results suggest that agreement between TST and QFT is lower in TST positive than in negative subjects, being lower in individuals treated for LTBI. Quantiferon does not seem to have brought significant improvement in the diagnosis of LTBI.


Subject(s)
Antibodies, Bacterial/analysis , Interferon-gamma/immunology , Mycobacterium tuberculosis/immunology , Tuberculin Test/methods , Tuberculosis/diagnosis , Adult , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Interferon-gamma/blood , Male , Observer Variation , Reproducibility of Results , Retrospective Studies , Tuberculosis/blood
5.
Sci Rep ; 5: 17771, 2015 Dec 08.
Article in English | MEDLINE | ID: mdl-26644220

ABSTRACT

We report on the intriguing evolution of the dynamical spin correlations of the frustrated spinel ZnMn2O4. Inelastic neutron scattering and magnetization studies reveal that the dynamical correlations at high temperatures are 1D. At lower temperature, these dynamical correlations become 2D. Surprisingly, the dynamical correlations condense into a quasi 2D Ising-like ordered state, making this a rare observation of two dimensional order on the spinel lattice. Remarkably, 3D ordering is not observed down to temperatures as low as 300 mK. This unprecedented dimensional crossover stems from frustrated exchange couplings due to the huge Jahn-Teller distortions around Mn(3+) ions on the spinel lattice.

6.
Pediatr Infect Dis J ; 18(5): 414-9, 1999 May.
Article in English | MEDLINE | ID: mdl-10353513

ABSTRACT

BACKGROUND: Describing the epidemiology of varicella is relevant to the development of specific prevention strategies and to building up of economic models evaluating the cost:efficiency ratios of these strategies. AIM: Our study was designed to describe the epidemiology of chickenpox among Italian children and to assess the resulting economic and health burden on the country. METHODS: Thirty-nine Italian pediatricians participated in a sentinel network on pediatric infectious diseases representing a total pediatric population of 30 168 children. Each case of varicella observed from January through December, 1997, was recorded. Economic analysis was conducted from the societal point of view. All costs were broken down into two groups: direct and indirect costs. RESULTS: A total of 1599 cases of varicella were reported among children 0 to 14 years old. There were 1266 primary cases (mean age, 4.5 +/- 2 years) and 333 secondary cases (mean age, 3.6 +/- 3.2 years). The global incidence of chickenpox was 51.01/1000/year. Complications were seen in 56 cases (3.5%). Drugs were prescribed in 672 cases. A group of adults (364 susceptible and 193 with uncertain status) were exposed to primary cases. Seventy (12.5%) were eventually infected among whom there were 4 pregnant women. For pediatric patients an average cost of $146.90 (250 400 lire) was estimated; this is largely accounted for by indirect costs. CONCLUSIONS: The epidemiology of varicella in Italy is consistent with that found in previous studies in industrialized countries. Severe complications did not occur in our population. We believe that the health arguments in favor of universal vaccination of children > 18 months of age do not differ in our own country from those of other industrialized nations. Our data could now be incorporated into pharmacoeconomic models to establish cost-efficient strategies for Italy.


Subject(s)
Chickenpox/economics , Chickenpox/epidemiology , Adolescent , Adult , Age Distribution , Child , Child, Preschool , Cohort Studies , Cost of Illness , Humans , Incidence , Infant , Infant, Newborn , Italy/epidemiology , Pediatrics , Prospective Studies , Sentinel Surveillance
7.
Clin Microbiol Infect ; 10(11): 1017-9, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15522008

ABSTRACT

This report describes the characterisation of a mycobacterium involved in a case of septic arthritis in an AIDS patient that was treated successfully with specific anti-mycobacterial drugs. The biochemical and cultural features, and the mycolic acid pattern as assessed by high-performance liquid chromatography, were fully compatible with the isolate being Mycobacterium flavescens. However, the isolate's 16S rDNA sequence differed by five nucleotides from the two known sequevars of M. flavescens, thus indicating that this isolate belonged to a new 16S rDNA sequevar.


Subject(s)
AIDS-Related Opportunistic Infections/microbiology , Mycobacterium Infections/microbiology , Nontuberculous Mycobacteria/classification , Nontuberculous Mycobacteria/genetics , Synovial Fluid/microbiology , Adult , Base Sequence , DNA, Ribosomal/analysis , HIV Infections/complications , Humans , Male , Molecular Sequence Data , Nontuberculous Mycobacteria/isolation & purification , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
8.
Clin Implant Dent Relat Res ; 2(3): 152-8, 2000.
Article in English | MEDLINE | ID: mdl-11359260

ABSTRACT

BACKGROUND: Implant restorations first started with total edentulism. Later, the scientific community gave its approval for restorations in partial edentulism, and only recently some studies confirmed the validity of the treatment for single-tooth replacement. PURPOSE: The purpose of the study was to evaluate implant survival and prosthesis stability of Brånemark implants (titanium screws) when used routinely for single-tooth replacement in all regions. MATERIALS AND METHODS: Two hundred and fourteen patients received 252 implants for single-tooth replacement over a period of 8 years at five private clinics in Italy. The patients were treated in accordance with the protocol for Brånemark implants, and the data gathered have been analyzed according to established evaluation methods. RESULTS: During the observation period, 10 failures were recorded and 229 restorations were carried out. After the first year of loading, the total cumulative survival rate (CSR) was 96%, which then remained stable over the study time. The most frequent complication was loosening of the abutment screws (n = 22), amounting to 35% of all of the complications. This problem was related mainly to earlier types of abutments, whereas the more recent design, CeraOne abutment, showed a low frequency of screw loosening. CONCLUSIONS: The high survival rate, which is similar to that presented for prospective multicenter studies for single-tooth restorations with Brånemark implants, led to the conclusion that the use of this treatment modality is a reliable treatment for routine use in all oral regions.


Subject(s)
Dental Implants, Single-Tooth/statistics & numerical data , Practice Patterns, Dentists'/statistics & numerical data , Adolescent , Adult , Age Distribution , Aged , Dental Abutments , Dental Prosthesis Design , Dental Restoration Failure , Female , Humans , Male , Middle Aged , Retrospective Studies
9.
Minerva Med ; 88(10): 405-10, 1997 Oct.
Article in Italian | MEDLINE | ID: mdl-9417535

ABSTRACT

A new autosomal-dominant genetic disorder, which has been recently identified by our group is described. The disease is clinically characterized by the combination of a substantial increase of serum ferritin and early-onset bilateral cataract. Moreover, it is clearly distinguishable from genetic hemochromatosis because of: 1) normal to low serum iron and transferrin saturation, without evidence of parenchymal iron overload; 2) the dominant transmission; 3) the lack of any relation with HLA; 4) the rapid development of iron-deficient anemia when unnecessary phlebotomies are performed. The molecular basis of the new syndrome is a mutation in the L-subunit ferritin gene on chromosome 19 (19q13.3-->19qter). The mutation involves a five nucleotide sequence [CAGUG] of the iron-responsive-element (IRE), which is critical for the post-transcriptional regulation of ferritin synthesis by means of the binding with an Iron Regulatory Protein. As a consequence, ferritin synthesis is up-regulated, irrespective of cell iron status.


Subject(s)
Cataract , Ferritins/blood , Adult , Cataract/diagnosis , Cataract/genetics , Ferritins/genetics , Humans , Male , Syndrome
10.
Minerva Stomatol ; 38(4): 461-6, 1989 Apr.
Article in Italian | MEDLINE | ID: mdl-2659960

ABSTRACT

The high incidence of third molar extraction is related to their frequent pathology. The use of an uncomplicated and reliable diagnostic and therapeutic protocol therefore became extremely important. The protocol has to include careful selection and preparation as well as the appropriate choice of instruments and surgical techniques. This is even more important, considering the elective nature of the procedure and the local and more rarely, systemic complications that could develop.


Subject(s)
Molar, Third , Tooth Extraction/methods , Humans , Mandible , Tooth Extraction/instrumentation
11.
G Ital Nefrol ; 21(4): 387-90, 2004.
Article in Italian | MEDLINE | ID: mdl-15526404

ABSTRACT

BACKGROUND: Red cell Cartwright antigen (Yta) is very common in the general population therefore patients without red cell Cartwright antigen and with anti-Yta alloantibodies due to previous exposure to the antigen are rare. Report about clinical significance of Yta red cell alloantibodies in hemodialysis (HD) patients are scarce. CASE REPORT: We report a cirrhotic uremic patient with anti-Yta antibodies who received Yta positive red cells. No adverse reactions nor hemolysis were detected. CONCLUSIONS: We concluded that dialysis patients with anti-Yta antibodies could be safely transfused with blood from Cartwright positive donors.


Subject(s)
Blood Transfusion , Erythrocytes/immunology , Isoantibodies/blood , Isoantigens/immunology , Renal Dialysis , Uremia/blood , Uremia/therapy , Adult , Humans , Male
12.
Pathologica ; 106(4): 315-21, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25845046

ABSTRACT

The homeodomain-containing transcription factor pancreatic duodenal homeobox 1 (PDX-1) plays a key role in pancreatic development and ß-cell function. It is a major regulator of transcription in pancreatic cells, and transactivates the insulin gene by binding to a specific DNA motif in its promoter region. Glucose also regulates insulin gene transcription through PDX-1. It has been shown that PDX-1 is required for maintaining pancreatic islet functions by activating gene expression and has a dual role in pancreatic development. It initially contributes to pancreatic formation during embryogenesis and subsequently regulates the pancreatic islet cell physiology in mature islet cells. Because of this key role in the embryologic development of the pancreas, PDX-1 expression has been investigated in pancreatic cancer cell lines and human tumors. Moreover, a few reports have described expression of PDX-1 in other human neoplasms and have investigated its potential role in differential diagnosis, but data on normal human tissues are lacking. Understanding the molecular mechanisms of pancreas formation, and especially the function of PDX-1, may contribute to the improved treatment and prevention of debilitating diseases such as diabetes, insulinomas and pancreatic carcinomas. Nevertheless, further studies are needed concerning its possible application in routine practice.


Subject(s)
Genes, Homeobox/physiology , Homeodomain Proteins/metabolism , Islets of Langerhans/metabolism , Trans-Activators/metabolism , Animals , DNA-Binding Proteins/metabolism , Diabetes Complications/metabolism , Diabetes Complications/therapy , Humans , Islets of Langerhans/pathology , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/therapy , Pancreatic Neoplasms
13.
Toxicol Lett ; 192(1): 29-33, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-19900514

ABSTRACT

Assessing CYP2E1 phenotype in vivo may be important to predict individual susceptibility to those chemicals, including benzene, which are metabolically activated by this isoenzyme. Chlorzoxazone (CHZ), a specific CYP2E1 substrate, is readily hydroxylated to 6-OH-chlorzoxazone (6-OH-CHZ) by liver CYP2E1 and the metabolic ratio 6-OH-CHZ/CHZ in serum (MR) is a specific and sensitive biomarker of CYP2E1 activity in vivo in humans. We used this MR as a potential biomarker of effect in benzene-treated rats and, also, in humans occupationally exposed to low levels of benzene. Male Sprague-Dawley rats (375-400g b.w.) were treated i.p. for 3 days with either a 0.5ml solution of benzene (5mmol/kg b.w.) in corn oil, or 0.5ml corn oil alone. Twenty-four hours after the last injection, a polyethylene glycol (PEG) solution of CHZ (20mg/kg b.w.) was injected i.p. in both treated and control animals. After 2, 5, 10, 15, 20, 30, 45, 60, 90, 120, 180, and 240min from injection, 0.2ml blood was taken from the tip tail and stored at -20 degrees C until analysis. A modified reverse phase HPLC method using a 5microm Ultrasphere C18 column equipped with a direct-connection ODS guard column, was used to measure CHZ and its metabolite 6-OH-CHZ in serum. No statistically significant difference in the MR was observed, at any sampling time, between benzene-treated and control rats. The concentration-versus-time area under the curve (AUC), however, was lower (p<0.05, Mann-Whitney test), whereas the systemic clearance was higher (p<0.05) in treated than in control rats. Eleven petrochemical workers occupationally exposed to low levels of airborne benzene (mean+/-SD, 25.0+/-24.4microg/m(3)) and 13 non-exposed controls from the same factory (mean+/-SD, 6.7+/-4.0microg/m(3)) signed an informed consent form and were administered 500mg CHZ p.o. Two hours later a venous blood sample was taken for CHZ and 6-OH-CHZ measurements. Despite exposed subjects showed significantly higher levels of t,t-MA and S-PMA, two biomarkers of exposure to benzene, than non-exposed workers, no difference in the MR mean values+/-SD was found between exposed (0.59+/-0.29) and non-exposed (0.57+/-0.23) subjects. So, benzene was found to modify CHZ disposition, but not CYP2E1 phenotype in benzene-treated rats, nor in workers exposed to benzene, probably due to the levels of exposure being too low.


Subject(s)
Benzene/pharmacokinetics , Chlorzoxazone/analogs & derivatives , Chlorzoxazone/pharmacokinetics , Cytochrome P-450 CYP2E1/metabolism , Occupational Exposure/analysis , Acetylcysteine/analogs & derivatives , Acetylcysteine/urine , Animals , Area Under Curve , Benzene/toxicity , Biomarkers/blood , Biomarkers/metabolism , Chlorzoxazone/blood , Chromatography, High Pressure Liquid , Humans , Male , Phenotype , Random Allocation , Rats , Rats, Sprague-Dawley , Sorbic Acid/analogs & derivatives , Sorbic Acid/analysis , Statistics, Nonparametric
16.
Haematologica ; 76(1): 8-13, 1991.
Article in English | MEDLINE | ID: mdl-1676012

ABSTRACT

BACKGROUND: The role of HLA-DP as transplantation antigen in contributing to GvHD is a matter of current debate. HLA-DP, is encoded centromeric to DR-DQ and its alleles are in weak linkage disequilibrium with the rest of the MHC; thus a certain number of HLA matched pairs could be actually DP incompatible to study a possible correlation between HLA-DP matching and GvHD, 24 HLA identical BMT/donor-recipient sibling pairs (serologically tested for HLA Class I and DR antigens) were tested for DQ and DP genes using restriction fragment length polymorphism (RFLP) analysis. METHODS: DNA extracts were digested according to a standard procedure with two different restriction enzymes (HIND III and MSP I) and hybridised with DQ (alpha and beta) and DP (alpha and beta) specific probes. Highly stringent hybridization and washing conditions were used to prevent cross-hybridizations. RESULTS: Twenty four out of 24 pairs proved to be DQ and DP identical. GvHD developed in 16 out of 24 (66.6%) recipients. DISCUSSION: These data suggest that DNa analysis of DQ-DP regions, with the probes and enzymes used, does not give predictive informations for GvHD in HLA genotypically identical pairs.


Subject(s)
Bone Marrow Transplantation , Graft vs Host Disease/diagnosis , HLA-DP Antigens/genetics , HLA-DQ Antigens/genetics , Adolescent , Adult , Blotting, Southern , Bone Marrow/immunology , Bone Marrow/ultrastructure , DNA , Female , Genotype , Graft vs Host Disease/immunology , HLA-DP Antigens/immunology , HLA-DQ Antigens/immunology , Humans , Male , Middle Aged , Oligonucleotide Probes , Polymorphism, Restriction Fragment Length
17.
Eur J Clin Microbiol Infect Dis ; 21(4): 283-9, 2002 Apr.
Article in English | MEDLINE | ID: mdl-12072939

ABSTRACT

The performance of two commercial chromogenic media for the isolation and presumptive identification of urinary tract pathogens, the CPS ID2 (bioMérieux, France) and the CHROMagar Orientation (BBL Becton Dickinson, USA), was evaluated and compared with that of cystine-lactose-electrolyte-deficient agar and tryptic soy agar with 5% sheep blood. The detection, determination of bacterial counts, and presumptive identification of bacteria causing urinary tract infections were evaluated in 3,000 urine specimens. The two chromogenic media showed excellent correlation with the standard media for the detection and the bacterial count of urinary pathogens. The Escherichia coli strains produced the expected colour on the CHROMagar Orientation and the CPS ID2 media in 99% and 90% of the cases, respectively. The Klebsiella-Enterobacter-Citrobacter and the Proteus-Morganella-Providencia groups were easily identified on both chromogenic media, but further biochemical tests were needed to differentiate them to a species level. Both media enabled the differentiation, with varying degrees of difficulty, of Pseudomonas spp. strains from members of the family Enterobacteriaceae. All isolates of Enterococcus spp. were correctly identified and were easily distinguished from the Streptococcus agalactiae isolates. Staphylococcus saprophyticus isolates were easy to identify only on the CHROMagar Orientation medium. No substantial difference was observed when comparing the results of the susceptibility tests, which were performed according to the standardized disk diffusion method as described by the National Committee for Clinical Laboratory Standards, for colonies recovered from the blood agar versus those recovered from the chromogenic media. In conclusion, the CPS ID2 and CHROMagar Orientation media enabled excellent detection, count determination, and presumptive identification of urinary pathogens, both in pure and mixed cultures, and reliable and accurate antimicrobial susceptibility testing directly from primary isolates. Moreover, these media allowed a remarkable reduction in the workload and a significant savings of time. On the basis of their performance, these media can replace the standard primary plating media used in the routine diagnosis of urinary tract infections.


Subject(s)
Chromogenic Compounds , Culture Media , Urinary Tract Infections/microbiology , Urinary Tract Infections/urine , Urine/microbiology , Candida/isolation & purification , Colony Count, Microbial , Drug Resistance, Bacterial , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Humans , Microbial Sensitivity Tests
18.
Plant Physiol ; 125(4): 2053-8, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11299384

ABSTRACT

Azospirillum species are plant growth-promotive bacteria whose beneficial effects have been postulated to be partially due to production of phytohormones, including gibberellins (GAs). In this work, Azospirillum brasilense strain Cd and Azospirillum lipoferum strain USA 5b promoted sheath elongation growth of two single gene GA-deficient dwarf rice (Oryza sativa) mutants, dy and dx, when the inoculated seedlings were supplied with [17,17-2H2]GA20-glucosyl ester or [17,17- 2H2]GA20-glucosyl ether. Results of capillary gas chromatography-mass spectrometry analysis show that this growth was due primarily to release of the aglycone [17,17-2H2]GA20 and its subsequent 3beta-hydroxylation to [17,17-2H2]GA1 by the microorganism for the dy mutant, and by both the rice plant and microorganism for the dx mutant.


Subject(s)
Azospirillum brasilense/metabolism , Azospirillum/metabolism , Gibberellins/metabolism , Oryza/microbiology , Oryza/physiology , Azospirillum/growth & development , Azospirillum brasilense/growth & development , Deuterium , Gas Chromatography-Mass Spectrometry , Genes, Plant , Gibberellins/chemistry , Hydrolysis , Oryza/genetics , Plant Roots/metabolism
19.
Inorg Chem ; 39(14): 2970-6, 2000 Jul 10.
Article in English | MEDLINE | ID: mdl-11196891

ABSTRACT

Single crystals of A2ThP3Se9 (A = K (I), Rb (II)) and Cs4Th2PsSe17 (III) form from the reaction of Th and P in a molten A2Se3/Se (A = K, Rb, Cs) flux at 750 degrees C for 100 h. Compound I crystallizes in the triclinic space group P1 (No. 2) with unit cell parameters a = 10.4582(5) A, b = 16.5384(8) A, c = 10.2245(5) A, alpha = 107.637(1); beta = 91.652(1); gamma = 90.343(1) degrees, and Z = 2. Compound II crystallizes in the triclinic space group P1 (No. 2) with the unit cell parameters a = 10.5369(5) A, b = 16.6914(8) A, c = 10.2864(5) A, alpha = 107.614(1) degrees, beta = 92.059(1) degrees, gamma = 90.409(1) degrees, and Z = 2. These structures consist of infinite chains of corner-sharing [Th2Se14] units linked by (P2Se6)4- anions in two directions to form a ribbonlike structure along the [100] direction. Compounds I and II are isostructural with the previously reported K2UP3Se9. Compound III crystallizes in the monoclinic space group P2(1)/c (No. 14) with unit cell parameters a = 10.238(1) A, b = 32.182(2) A, c = 10.749(1) A; beta = 95.832(1) degrees, and Z = 4. Cs4Th2P5Se17 consists of infinite chains of corner-sharing, polyhedral [Th2Se13] units that are also linked by (P2Se6)4- anions in the [100] and [010] directions to form a layered structure. The structure of III features an (Se2)2- anion that is bound eta 2 to Th(2) and eta 1 to Th(1). This anion influences the coordination sphere of the 9-coordinate Th(2) atom such that it is best described as bicapped trigonal prismatic where the eta 2-bound anion occupies one coordination site. The composition of III may be formulated as Cs4Th2(P2Se6)5/2(Se2) due to the presence of the (Se2)2- unit. Raman spectra for these compounds and their interpretation are reported.

20.
Mondo Ortod ; 14(5): 609-14, 1989.
Article in Italian | MEDLINE | ID: mdl-2640946

ABSTRACT

In this paper, the Authors present epidemiology, ethiopatology, diagnosis and treatments elements of the impacted canines. Furthermore they describe the different surgical techniques needed for the exposure of these teeth.


Subject(s)
Cuspid/pathology , Tooth Movement Techniques , Tooth, Impacted/surgery , Cuspid/surgery , Humans , Maxilla , Tooth, Impacted/therapy
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