Intercollegiate usage schedule and the impact resistance of used football helmet faceshields.

PURPOSE: Although new polycarbonate helmet faceshields can withstand impacts exceeding forces of 2,400 N, repeated impacts and ultraviolet radiation degrade the structural integrity. In this study, the impact resistances of unused, solar-radiated, and of game-used faceshields were analyzed. Also, Division 1 National Collegiate Athletic Association football programs were surveyed concerning their faceshield practices. METHODS: Impact resistance was tested by impacting faceshields with baseballs at velocities exceeding 67.1 m/s. Twenty-four new faceshields were exposed to southern daylight, 3 hours per day for 3 months before testing. Subsequent testing was performed on 60 game-used faceshields. Additionally, a faceshield utilization survey was distributed to 117 college programs. RESULTS: Solar-irradiated shields did not fail at maximum test velocity. The survivability of nonimpacted shields was greater than game-worn shields (P = 0.0003). Fifty-nine surveys were returned with 58 programs reporting faceshield use. Approximately 21 players per program use a faceshield. The main reason reported for use was aesthetic. Only 21% of reporting programs require a faceshield for players with reduced visual acuity in 1 eye. CONCLUSION: Faceshields lose impact resistance with typical use. Programs should incorporate a policy for replacement and require that players with reduced vision in at least 1 eye wear a faceshield.

First Report of Lethal Yellowing Group (16Sr IV) of Phytoplasmas in Vernonia cinerea in Jamaica.

Coconut lethal yellowing disease (CLY) has had a devastating effect on the coconut (Cocos nucifera L.) industry in Jamaica and Latin America. A study was conducted in Jamaica during 2005 to identify alternate hosts of the CLY phytoplasma. Since weeds are known to act as reservoir hosts of numerous pathogens, Vernonia cinerea (L.) (Asteraceae), a prevalent weed species on coconut farms island-wide, was collected from coconut farms in areas of high and low levels of CLY incidence, although none of the plants displayed disease symptoms. DNA was extracted from plant samples by the method of Dellaporta et al. (1) and analyzed by nested PCR assay employing phytoplasma universal rRNA operon primers P1/P7 (2,4) and LY16Sf/LY16-23Sr (3). DNA derived from CLY-diseased or healthy coconut palm served as positive and negative controls, respectively, in each assay. Amplification of an rDNA product of the expected size (1.7 kb) confirmed phytoplasma infections in 53 of 118 (44.9%) V. cinerea test plants. Twenty-seven of the rDNA PCR products were analyzed by digestion with restriction enducleases RsaI, MspI, MseI, TaqI, HinfI, and HhaI. The restriction fragment length polymorphism profiles obtained were similar to that observed in the CLY-infected coconut palm. V. cinerea rDNA amplicons were cloned and sequenced (in both directions) and a representative sequence was deposited in GenBank (Accession No. EU057983). Blast analysis determined this sequence to be most similar (99%) to that of CLY phytoplasma in Jamaica (Accession No. AF49807) and Florida (Accession No. AF498309). To our knowledge, this is the first report of the 16Sr IV group of phytoplasmas infecting V. cinerea. Presence of the lethal yellowing phytoplasmas in dicotyledonous plant species has important epidemiological implications concerning vector identity and ecology. Futhermore, it is now evident that weed control on coconut farms could assist in the management of CLY disease in Jamaica. References: (1) S. L. Dellaporta et al. Plant Mol. Biol. Rep. 1:19, 1993. (2) S. Deng and C. Hiruki. J. Microbiol. Methods 14:53, 1991. (3) N. A. Harrison et al. Ann. Appl. Biol. 141:183, 2002. (4) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996.

First Report of Lethal Yellowing Disease of Coconut Palms Caused by Phytoplasma on Nevis Island.

Coconuts (Cocos nucifera) are an important small-holder's crop in many tropical countries and are used to enhance esthetics of coastal areas. Lethal yellowing (LY) is the single most important plant disease affecting the coconut industry in Jamaica. It affects many palm species in Jamaica, Florida, and Guatemala. This coconut disease was first recorded in Grand Cayman Island in 1834 and Jamaica in 1884. Symptoms of LY disease include premature nut fall, necrosis of the inflorescence, yellowing of the leaves, and defoliation. Thirty-eight coconut palms displaying symptoms indicative of LY disease were sampled in April, 2005 at several locations in Nevis. Immature leaf tissues (leaf bases adjacent to the apical meristem) and nondestructive (boring with a bit and braces) samples were collected from disease and healthy control coconut trees. DNA was extracted (2). The first round of polymerase chain reaction (PCR) with phytoplasma universal primer pair P1/P7 (1,3) resulted in an rDNA fragment of 1.8 kb, and a subsequent nested PCR using LY16-23Sr/LY16Sf primers yielded an amplicon of 1.74 kb (4). Purified product was cloned for sequencing. Sequences obtained were analyzed with Vector NTI Software Suite. The sequence of LYN 18-3 was entered in Genbank and Accession No. DQ378279 was assigned. LYN 18-3 has approximately 99% homology with LY Phytoplasma U18747 from Florida (Manila palm [Veitchia merrillii]). The disease-associated phytoplasma was reliably detected in immature tissues and trunk phloem at the onset of foliar symptoms in palms by PCR. On the basis of the results obtained from this study, it is clear that LY phytoplasma (16SrIV group) was found in the samples collected from Nevis. To our knowledge, this is the first report on lethal yellowing disease in Nevis. References: (1) S. Deng and C. Hiruki. J. Microbiol. Methods 14:53 1991. (2) J. J. Doyle and J. L. Doyle. Focus 12:13, 1990. (3) N. A. Harrison et al. Ann. Appl. Biol. 141:183, 2002. (4) C. D. Smart et al. Appl. Environ. Microbiol. 62:2988, 1996.

Canine transposition following trauma and loss of a central incisor: treatment options.

The aim of this article is to make clinicians aware of the possibility of canine transposition following loss of the upper central incisor. Using two case reports it considers the opportunities for rehabilitation of the occlusion, and discusses surgical, orthodontic and restorative considerations.

A conceptual model of community capacity development for health promotion in the Alberta Heart Health Project.

PURPOSE: The objective of this study was to derive a conceptual model of community capacity development for health promotion based on the 5-year demonstration phase of the Alberta Heart Health Project. METHOD: Community actions associated with successful implementation and uptake of initiatives in four diverse target sites were identified by case study evaluation. RESULTS: Thirteen common elements of capacity development were found across the projects and categorized to define three primary dimensions of the process: (a) leadership that provided a driving force for implementation, (b) policy making that ensured diffusion and sustainability, and (c) use of local community resources and infrastructure. A conceptual model was constructed using these 3 dimensions and their interactions. CONCLUSION: Effective implementation of community health initiatives to promote heart health can be conceptualized as the involvement of local leadership, policy advocacy, and enhancement of existing infrastructure. The model highlights building these dimensions of community capacity development for health promotion.

Special Care Dentistry: attitudes of Specialists in Paediatric Dentistry practising in the UK to the creation of a new specialty.

OBJECTIVES: This study was designed to examine the attitudes of Specialists in Paediatric Dentistry (SPDs) practising in the UK towards the creation of a specialty of Special Care Dentistry (SCD). DESIGN: Data were collected by postal questionnaire. Sample and methods. Two hundred and eleven dentists whose names were entered on the General Dental Council's Specialist List in Paediatric Dentistry, and who were resident and practising in the UK, were asked to complete a questionnaire consisting of both open and closed questions. RESULTS: Questionnaires were returned by 167 (79.2%) of the eligible SPDs. One hundred and sixty respondents (95.8%) expressed an opinion in relation to the creation of a specialty of SCD. One hundred and forty-three respondents (85.6%) stated that they supported such a proposal. However, slightly fewer (n = 149) respondents were prepared to indicate what they considered to be the remit of the proposed specialty. Ninety-two respondents (55.1%) considered that it should be restricted to the provision of specialist care for adults with 'special needs'; the remaining 57 respondents felt that it should provide specialist care across the entire age spectrum. CONCLUSIONS: Among SPDs, there is overwhelming support for the creation of a specialty of SCD, the majority view being that this should be dedicated to the provision of specialist care for adults with 'special needs'.

Characteristics and performance of the Sunna high dose dosemeter using green photoluminescence and UV absorption readout methods.

Growth in the use of ionising radiation for medical sterilisation and the potential for wide-scale international food irradiation have created the need for robust, mass-producible, inexpensive, and highly accurate radiation dosemeters. The Sunna dosemeter, lithium fluoride injection-moulded in a polyethylene matrix, can be read out using either green photoluminescence or ultraviolet (UV) absorption. The Sunna dosemeter can be mass-produced inexpensively with high precision. Both the photoluminescent and the UV absorption reader are simple and inexpensive. Both methods of analysis display negligible humidity effects, minimal dose rate dependence, acceptable post-irradiation effects, and permit measurements with a precision of nearly 1% 1sigma. The UV method shows negligible irradiation temperature effects from -30 degrees C to +60 degrees C. The photoluminescence method shows negligible irradiation temperature effects above room temperature for sterilisation dose levels and above. The dosimetry characteristics of these two readout methods are presented along with performance data in commercial sterilisation facilities.

RGD-independent binding of integrin alpha9beta1 to the ADAM-12 and -15 disintegrin domains mediates cell-cell interaction.

ADAMs (a disintegrin and metalloproteases) mediate several important processes (e.g. tumor necrosis factor-alpha release, fertilization, and myoblast fusion). The ADAM disintegrin domains generally lack RGD motifs, and their receptors are virtually unknown. Here we show that integrin alpha(9)beta(1) specifically interacts with the recombinant ADAMs-12 and -15 disintegrin domains in an RGD-independent manner. We also show that interaction between ADAM-12 or -15 and alpha(9)beta(1) supports cell-cell interaction. Interestingly, the cation requirement and integrin activation status required for alpha(9)beta(1)/ADAM-mediated cell adhesion and cell-cell interaction is similar to those required for known integrin-extracellular matrix interaction. These results are quite different from recent reports that ADAM-2/alpha(6)beta(1) interaction during sperm/egg fusion requires an integrin activation status distinct from that for extracellular matrix interaction. These results suggest that alpha(9)beta(1) may be a major receptor for ADAMs that lack RGD motifs, and that, considering a wide distribution of ADAMs and alpha(9)beta(1), this interaction may be of potential biological and pathological significance.

Multiple discontinuous ligand-mimetic antibody binding sites define a ligand binding pocket in integrin alpha(IIb)beta(3).

Integrin alpha(IIb)beta(3), a platelet fibrinogen receptor, is critically involved in thrombosis and hemostasis. However, how ligands interact with alpha(IIb)beta(3) has been controversial. Ligand-mimetic anti-alpha(IIb)beta(3) antibodies (PAC-1, LJ-CP3, and OP-G2) contain the RGD-like RYD sequence in their CDR3 in the heavy chain and have structural and functional similarities to native ligands. We have located binding sites for ligand-mimetic antibodies in alpha(IIb) and beta(3) using human-to-mouse chimeras, which we expect to maintain functional integrity of alpha(IIb)beta(3). Here we report that these antibodies recognize several discontinuous binding sites in both the alpha(IIb) and beta(3) subunits; these binding sites are located in residues 156-162 and 229-230 of alpha(IIb) and residues 179-183 of beta(3). In contrast, several nonligand-mimetic antibodies (e.g. 7E3) recognize single epitopes in either subunit. Thus, binding to several discontinuous sites in both subunits is unique to ligand-mimetic antibodies. Interestingly, these binding sites overlap with several (but not all) of the sequences that have been reported to be critical for fibrinogen binding (e.g. N-terminal repeats 2-3 but not repeats 4-7, of alpha(IIb)). These results suggest that ligand-mimetic antibodies and probably native ligands may make direct contact with these discontinuous binding sites in both subunits, which may constitute a ligand-binding pocket.

Management of molar teeth with periodontal disease.

Over the years patients' attitudes towards maintaining a functional and aesthetic masticatory apparatus have improved, and their expectations of delivery of care by the dental professional have risen. With the advance of new techniques and materials, the periodontist can now offer an ever-expanding range of treatments in the management of molar teeth with periodontal disease. This paper considers such treatment in relation to the levels of disease present and within the overall context of adult restorative dental healthcare.

A New Tomato-Infecting Begomovirus in Barbados.

In September 1998, tomato plants in Barbados exhibited symptoms of severe leaf curling without marginal chlorosis. These symptoms were often associated with an increase in whitefly (Bemisia tabaci) populations. DNA was extracted from leaf tissue from symptomatic tomato plants. Polymerase chain reaction (PCR) was performed with DNA-A degenerate primer pair PAC1v1978/PAV1c715, which amplifies part of the rep gene, the cp gene, and the common region (CR), and with DNA-B primer pair PBC1v2039/PBV1c800, which amplifies part of the bc1 and bv1 genes and the CR (2). The amplified PCR fragments of DNA-A and DNA-B were 1.3 and 1.4 kb, respectively, which are the expected sizes from bipartite, whitefly-transmitted geminiviruses of the Western Hemisphere (2). DNA sequence of the cloned fragments of DNA-A and DNA-B are available as GenBank No. AF213013 and AF213014, respectively. The 181 nucleotides of the CR of DNA-A had a nucleotide identity of 96% with the CR of DNA-B, which indicates that this is a bipartite begomovirus. Pairwise comparisons using DNASTAR (DNASTAR, Madison, WI) of the sequenced part of DNA-A was most similar to Cabbage leaf curl virus (CaLCuV, 69%, U65529) and Squash leaf curl virus extended host range isolate (SqLCV-E, 64%, M38183), and <59% to 13 other bipartite Western Hemisphere geminiviruses and Tomato yellow leaf curl virus from Israel (X15656). Pairwise comparisons of the DNA-B fragment sequence was 59 and 55% similar to CaLCuV (U65530) and SqLCV-E (M38182), respectively. Phylogenetic analysis of DNA-A of the major groups of Western Hemisphere begomoviruses placed the Barbados tomato-infecting geminivirus in the cluster with CaLCuV and SqLCV-E (1), while DNA-B analysis placed it with CaLCuV. The DNA-A amplified fragment was used as a probe at high stringency with the dot blot hybridization assay using the Genius II labeling and detection kit (Boeringer Mannheim) to detect this geminivirus in tomato and several other plant species, which had typical geminiviral symptoms. Strong hybridization signals were obtained for all 23 tomato plants with symptoms, weak signals were observed for two of three muskmelon and two of seven watermelon plants, all with leaf curling symptoms. No hybridization signals were observed for peppers with leaf curling symptoms and two weed species, Macroptilium lathyroides and Rhynchosia minima, with golden mosaic symptoms or with the symptomless plant species used as negative controls. The weak signals observed from watermelon and muskmelon samples indicated the presence of low virus titer or geminiviruses distinct from this tomato virus. The presence of viral DNA in these two plant species was confirmed by PCR with degenerate primers described above. Resulting database searches of sequences in the GenBank revealed that the Barbados tomato virus appears to be a previously unreported virus. This new virus is given the provisional name Tomato leaf curl Barbados virus (ToLCBBV). References: (1) J. C. Faria et al. Phytopathology 84:321, 1994. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993.

The effect of multiple anticonvulsant therapy on the expression of phenytoin-induced gingival overgrowth.

The potential effect of co-medication with phenobarbitone, primidone and carbamazepine on plasma and saliva concentrations of 5-(4-hydroxyphenyl)-5-phenylhydantoin (4-HPPH), the major metabolite of phenytoin in man and on the incidence of phenytoin-induced gingival overgrowth was investigated in a group of 36 adult epileptic patients. There were no significant differences in plasma or saliva concentrations of 4-HPPH or phenytoin in patients prescribed phenytoin alone, compared to those who received phenytoin with either phenobarbitone, primidone, or carbamazepine. In addition, the extent and the incidence of gingival overgrowth were similar in the 2 groups. The results suggest that chronic co-medication with other anti-convulsant drugs which induce phenytoin metabolism, does not affect the plasma or saliva 4-HPPB steady-state levels, nor the degree of gingival overgrowth in adult epileptic patients on therapy with phenytoin.

Alpha 3 beta 1 adhesion to laminin-5 and invasin: critical and differential role of integrin residues clustered at the boundary between alpha 3 N-terminal repeats 2 and 3.

Integrin/ligand interaction is a therapeutic target for many diseases. We previously reported that residues critical for ligand binding are clustered in N-terminal repeat 3 (in the predicted 2-3 loop) of alpha 4, alpha 5 and alpha IIb. Here we have localized residues critical for ligand binding in the alpha 3 subunit of integrin alpha 3 beta 1 with distinct ligand specificity (laminin-5). We identified an alpha 3 epitope common to several function-blocking anti-alpha 3 antibodies at the boundary between repeats 1 and 2 (residues 75-80). We found that swapping the predicted 4-1 loop (residues 153-165) at the boundary between repeats 2 and 3 with the corresponding alpha 4 sequence and mutating Thr-162 and Gly-163 residues in this predicted loop block laminin-5 binding. Thr-162 and Gly-163 and the antibody epitope are separated in the primary structure; however, they are close to each other in the proposed beta-propeller model. Mutating residues recently reported to block (Tyr-186 and Trp-188) or enhance (Asp-122) laminin-5 binding to alpha 3 beta 1 [Krukonis, E. S., Dersch, P., Eble, J. A., and Isberg, R. R.(1998) J. Biol. Chem. 273, 31837-31843] did not affect laminin-5 binding under the assay conditions used. Thr-162 and Gly-163 are not critical for adhesion to invasin, indicating that laminin-5 and invasin may use different recognition mechanisms, and that mutation of Thr-162 and Gly-163 does not drastically affect the integrity of alpha 3 beta 1. These results suggest that residues critical for ligand binding may be similarly (but not identically) located in repeat 3 of the alpha subunit regardless of ligand specificity.

Phenytoin metabolism to 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH) in man, cat and rat in vitro and in vivo, and susceptibility to phenytoin-induced gingival overgrowth.

Interspecies differences in phenytoin (PHT) metabolism to 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH) were examined in human, cat and rat hepatic microsomes in vitro. Rat liver microsomes were 25 and 650 times more efficient at the conversion of PHT to HPPH than human and cat liver microsomes, respectively. Sulphaphenazole (83%) and tolbutamide (TOL) (64%) were the most potent inhibitors of HPPH formation in human liver microsomes, while ciprofloxacin (27%), enoxacin (27%) and TOL (26%) produced the greatest inhibition in cat liver microsomes. TOL was tested for its effect on HPPH formation and gingival overgrowth in cats in vivo. Eight cats received PHT sodium (4 mg/kg/d) and another 8 cats received PHT sodium together with TOL (20 mg/kg/d) for 10 wk. Six cats (75%) in the PHT group and 4 cats (50%) in the PHT & TOL group developed significant gingival overgrowth by the end of the study. However, the extent and incidence of the overgrowth were similar in the 2 groups. There were no significant differences in mean AUC 0-10 weeks for plasma PHT (552.90 +/- 29.6 micrograms.d/mL [PHT alone] vs. 582.41 +/- 24.49 micrograms.d/mL [PHT & TOL]) and unconjugated HPPH (1016.4 +/- 295.5 ng.d/mL [PHT alone] vs. 1174.5 +/- 397.2 ng.d/mL [PHT & TOL]) concentrations between the 2 groups of cats. Neither PHT nor HPPH were detectable in the plasma of 8 rats which received PHT (4 mg/kg/d) over a 10-wk period. The rats showed no sign of gingival inflammation (mean gingival index = 0) or gingival overgrowth (mean gingival overgrowth index = 0). Thirty-six adult epileptic patients on chronic PHT therapy were examined; 17 (47%) of the patients demonstrated clinically significant overgrowth. The mean steady-state plasma PHT concentration was comparable to, and the mean plasma unconjugated HPPH concentration 5-fold greater than, that observed in the cats. The results suggest that the rapid metabolism and elimination of PHT and HPPH in the rat may enable it to become more resistant towards developing gingival overgrowth, compared to the cat and man.

Integrin alpha3beta1 expressed by human colon cancer cells is a major carrier of oncodevelopmental carbohydrate epitopes.

Oncodevelopmental carbohydrate epitopes are a common feature of human colorectal carcinoma, yet their biological significance remains unclear. We have shown previously that monoclonal antibody (MAb) 3A7, which recognizes a determinant on type 2 chain blood group A and B oligosaccharides, detects oncodevelopmental changes in azoxymethane-induced rat colon tumors and some human colon cancer cell lines. (Laferté S et al. [19951 J. Cell. Biochem. 57:101-119). In this study, we set out to purify gp140, the major glycoprotein carrier of the 3A7 epitope expressed by human colon cancer cells, as a first step towards elucidating the contribution of the 3A7 epitope and its major glycoprotein carrier to colon cancer progression. To this end, gp140 was purified from HT29 cells and used for the preparation of polypeptide-specific monoclonal antibodies. Five monoclonal antibodies (7A8, 7B11, 8C7, 8H7, and 11D4) immunoprecipitated a 3A7-immunoreactive glycoprotein complex of 140 kDa which was subsequently identified by partial protein sequencing as alpha3beta1 integrin. Flow cytometric analysis of Chinese hamster ovary (CHO) cells expressing different human integrin chains revealed that MAbs 7A8 and 7B11 detect the alpha3 integrin subunit whereas MAbs 8C7 and 8H7 detect the beta1 integrin subunit. MAb 11D4, which did not bind to any of the CHO transfectants, detected type 2 chain blood group A determinant. Flow cytometric analysis of a panel of human colon carcinoma cell lines obtained from blood group A, AB, or B individuals revealed a direct correlation between cell-surface expression of the 3A7 epitope and alpha3 integrin subunit, suggesting that alpha3beta1 integrin is a preferred target of the 3A7 epitope in colon cancer cells. Using lectins and glycosidases to examine further the carbohydrate structure of alpha3beta1 integrin, we demonstrated that it is a sialoglycoprotein containing both N- and O-linked oligosaccharides. In addition, both alpha3 and beta1 integrin subunits express beta1-6 branched Asn-linked oligosaccharides and short poly-N-acetyllactosamine units (Galbeta1-4GlcNAc-R; n < or = 3), glycans previously implicated in cancer metastasis.Thus, alpha3beta1 integrin expressed by human colon carcinoma cells is a major carrier of oncodevelopmental carbohydrate epitopes whose presence may modulate tumor cell adhesion, migration, and/or invasion.

Telemicrobiology: feasibility study.

BACKGROUND: Rural hospitals generally lack staffing with infectious disease specialists or pathologists. Without on-site pathologists, the range of microbiology services offered by clinical laboratories may be limited as well. OBJECTIVE: To study the feasibility of using static-image telepathology to evaluate Gram stains of microbiologic preparations. MATERIALS AND METHODS: In this retrospective feasibility study, three pathologists evaluated Gram stains of slides from 50 cases by two viewing modalities: static-image telepathology and conventional light microscopy. Digital video images of slides were captured at two magnifications (using 40x and 100x objective lenses) at 1024 x 768 x 24-bit color and transmitted over standard telephone lines at 14,400 kbps. Pathology reports and culture results served as "truth diagnoses." Categories of interpretations were correct, minor discrepancy, or major discrepancy with regard to the implications for patient care. RESULTS: The diagnostic accuracy of video image readings and conventional light microscopy readings were nearly identical, with no statistically significant differences in the performances of specialty and nonspecialty pathologists (P > 0.05). The mean accuracies of readings of the video images and light microscopy images were 95.3% and 95.4%, respectively. Taking into account the time required by a referring pathologist to capture video digital images, telemicrobiology was somewhat less efficient than conventional light microscopy. CONCLUSIONS: Pathologists can accurately evaluate digital video images of preselected fields on Gram-stained slides. In clinical practice, however, a limiting factor may be the availability of local personnel qualified to select the microscopic fields for evaluation by telepathologists. The adequacy of the video images suggests that telepathology may also be used for remote supervision of quality assurance programs in microbiology laboratories, as well as for remote proficiency training of laboratory personnel.