Determining the Optimal Technique for Bar Fixation in the Repair of Pectus Excavatum

Introduction: Pectus bar stabilizers are routinely used for bar fixation in the repair of pectus excavatum. We aimed to determine the optimum technique for bar fixation by reviewing our institutional experience with the use of bilateral, unilateral, and no stabilizer placement. Methods: Retrospective single pediatric center review of patients who underwent minimally invasive bar placement for pectus excavatum and subsequent bar removal between December 2001 and July 2019 was performed. Demographic data, details about the surgery, the number of bars and stabilizers used, and follow-up information were collected. Stabilizer-related complications included pain requiring stabilizer removal, surgical site infections (SSIs), and bar displacement. Data are presented as medians with interquartile ranges (IQRs) and frequencies with percentages. Results: A total of 561 patients were included. The cohort was predominantly male (83.1%, n = 466) with a median age at the time of bar placement of 15 years (IQR 12.4, 16.3) and a median Haller index of 3.8 (IQR 3.4, 4.5). Pain attributed to the stabilizer site that required removal was observed only in the bilateral stabilizer group (2.5%, n = 13). SSI related to the stabilizer site occurred in 1.8% (n = 9) of the bilateral stabilizer cases and 2.1% (n = 1) of the unilateral stabilizer cases. Bar displacement was observed in 0.6% (n = 3) of the bilateral stabilizer cases and 2 of those patients also had an SSI. There were no complications in the no stabilizer group. Conclusion: As the trend moves toward unilateral and no stabilizer use, we observe fewer cases of pain requiring stabilizer removal with no increase in bar displacements.

Relation of Crown Failure Load to Flexural Strength for Three Contemporary Dental Polymers

Polymeric materials show great promise for use in a variety of dental applications. Manufacturers generally provide flexural strength information based on standardized (ISO and ASTM) specimen dimensions and loading conditions. It is not clear, however, if flexural strength data are predictive of the clinical performance of dental crowns. The objectives of this study were, therefore, to determine whether flexural strengths, as measured via three-point bending (3PB), would be predictive of failure loads assessed via crunch-the-crown (CTC) tests. Three brands of polymers (Trilor, Juvora, and Pekkton) were fabricated into rectangular bars and fully contoured crowns (10 specimens of each polymer brand, 30 specimens of each shape). Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and burn off tests were used to characterize/confirm the materials. Bars were tested blindly in 3PB to determine flexural strength, and crowns were CTC-tested to determine failure load after luting to resin abutments. The statistical significance of the test results was evaluated via one-way ANOVA (α = 0.05) and Pearson's correlation coefficient, while regression analysis was used to test for a correlation between 3PB and CTC results. The fracture mechanisms and failure surface characteristics were characterized using scanning electron microscopy (SEM). There were significant differences (p < 0.05) in the mean crown failure loads (Trilor (7033 N) > Juvora (5217 N) > Pekkton (3023 N)) and mean flexural strengths of the bars (Trilor (468 MPa) > Juvora (197 MPa) = Pekkton (192 MPa)). The mode of crown fracture was different between the materials and included deformation (Juvora), ductile-to-brittle fracture (Pekkton), and a combination of cracks and deformation (Trilor). Flexural strengths did not correlate with the corresponding crown failure loads for any of the materials tested. These results suggest that dental practitioners should not rely on the flexural strengths reported from three-point bending tests, as advertised by the manufacturer, to predict the performance of polymeric crowns.

ABA supports AMA regarding monkeypox name change: A satire

The names of organizations, teams, and medical conditions can elicit controversy when presumedly unintentional defamation of a subset of individuals is perceived. Indeed, this has recently resulted in changing the names of sports teams and diseases. Previously, the ABA (American Baboon Association) solicited the other ABA (American Bar Association), and the drug reaction initially described to as baboon syndrome is now appropriately referred to as symmetrical drug-related intertriginous and flexural exanthema (SDRIFE). Currently, the AMA (American Monkey Association)-with the support of the ABA (American Baboon Association) -has notified the other AMA (American Medical Association) that they consider the name monkeypox unacceptable for this viral infection. The ABA (American Baboon Association) and the AMA (American Monkey Association) are fictional organizations created by the author for the purpose of this satire.

A Citywide Analysis of DWI Events in Association with Bar Reopening and Increased Restaurant Capacity

BACKGROUND

During the COVID-19 pandemic many bars closed. Simultaneously, many persons experienced stay at home orders linked to an increase in alcohol use. The net impact of these restrictions on the incidence of driving while intoxicated (DWI) events is unclear.

METHODS AND MATERIAL

We conducted a retrospective observational analysis using publicly reported data regarding police traffic encounters. We analyzed changes in DWI encounters in the San Antonio, TX metropolitan area before (1-14 October 2020) versus after (15-28 October 2020) bars reopened during the COVID-19 pandemic. We made these comparisons by comparing medians and through regression modelling to control for potential confounders.

RESULTS

During the study period, 16,609 police traffic encounters met inclusion criteria. Of these, 353 were DWI encounters, 594 were officer traffic stop encounters, 14,565 were traffic related encounters, 113 were wrong way driver encounters, and 984 were other traffic violations. In the before and after analysis, there was no difference in the daily median numbers of DWI encounters (12 versus 10, p=0.461), wrong way driver incidents (3 versus 2, p=0.328), or other traffic violations (34 versus 35, p=0.854). The multivariable regression model similarly identified no change in the daily incidence of DWI encounters (p=0.281).

CONCLUSIONS

We detected no change in the incidence of DWI encounters immediately following the reopening of bars in the San Antonio metropolitan area.

A one-year randomized trial

INTRODUCTION

This study aimed to evaluate peri-implant tissue health and patient satisfaction of vertical and inclined posterior implants for mandibular bar overdentures.

MATERIALS AND METHODS

Thirty edentulous participants received four implants in the interforaminal area of the mandible. The patients were randomly assigned into two equal groups; (1) vertical group (control): all implants were inserted vertically parallel to each other. Inclined group (study): the anterior implants were placed vertically, and the posterior implants were tilted 30° distally. Hader bar attachment with two 7 mm-distal cantilevers (vertical group) and without cantilevers (inclined group) was used to connect the implants to mandibular overdentures. Peri-implant tissue health (Plaque [PL] and gingival [GI] indices, pocket depth [PD], and crestal bone loss [CBL]) were evaluated after denture insertion (T0), 6 (T6), and 12 (T12) months after insertion. Patient satisfaction was evaluated using a visual analog scale after 12 months.

RESULTS

At T12, the vertical group showed significantly higher PL, PD, and CBL than the inclined group for anterior (p < 0.037) and posterior (p < 0.017) implants. The vertical group showed significantly higher GI than the inclined group for anterior implants (p = 0.003), and the inclined group showed significantly higher GI than the vertical group for posterior implants (p = 0.016). The inclined group showed significantly higher scores for general satisfaction (p = 0.049), prosthesis as a part of you (p = 0.013), appearance (p < 0.001), stability (p = 0.002), ease of cleaning (p < 0.001), and comfort (p = 0.001) than the vertical group.

CONCLUSION

Inclined posterior implants used to support mandibular bar overdentures are recommended than vertical implants, as it was associated with improved patient satisfaction and peri-implant tissue health.

Experimental and numerical investigations of fracture and fatigue behaviour of implant-supported bars with distal extension made of three different materials

The aim of this study was to investigate experimentally the fatigue and stability of three bar materials with distal extension at the molar region and to numerically analyse the biomechanical properties of the bar materials connected to overdentures in a patient individual model. A milled bar was designed for the mandible on four implants in the canine and second premolar region. Three bar materials were investigated: titanium (Ti), cobalt chromium (CoCr), and polyetherketonketon (PEKK). Firstly, static and fatigue tests were performed based on EN ISO 14801 in a commercial permanent loading set-up. Unilateral axial force was applied on the distal extension of the bars. Secondly, numerical models were created. Different bar materials and loading scenarios were analysed. The static fracture limit of the three materials was 1,750 N, 780 N, 310 N for Ti, CoCr, and PEKK, respectively. The Wöhler curves showed comparable fatigue limits of 200 N, 160 N, and 150 N for titanium, CoCr, and PEKK, respectively. The stress at the distal extension was 2,600 MPa (Ti), 1,000 MPa (CoCr), and 270 MPa (PEKK). All loading simulations with the PEKK bar showed higher stresses in the implants and in the bone bed as well as higher displacements of the over denture in comparison to metal bars. PEKK showed different mechanical behaviour compared to Ti and CoCr. The distribution of stresses within the PEKK bar was wider than the area of loading which probably leads to fatigue of the whole bar and not only the part under load.

A Comparison of Biomechanical Properties of Implant-Retained Overdenture Based on Precision Attachment Type

This paper aims to compare, in vitro, the biomechanical properties of an overdenture retained by two bar-retained implants and an overdenture retained by two bar-retained implants with ball attachments. An edentulous mandible model was prepared for the study based on the FRASACO mold with two implants. In the first system, the “rider” type (PRECI-HORIX, CEKA) retention structure and the complete mandibular denture with the matrix were made. In the second system, the “rider” type retention suprastructure was also used. In the distal part, (CEKA) clips were placed symmetrically, and a complete mandibular denture, together with the matrix on the bar, and the clip patrices were made. A numerical model was developed for each system where all elements were positioned and related to geometric relations, as in reality. The FEA analysis (finite element analysis) was carried out for seven types of loads: with vertical forces of 20, 50, and 100 N and oblique forces of 20 and 50 N acting on individual teeth of the denture, namely central incisor, canine, and first molar. Displacements, stresses, and deformations within the systems were investigated. Maximum denture displacement in the first system was 0.7 mm. Maximum bar stress amounted to 27.528 MPa, and implant stress to 23.16 MPa. Maximum denture displacement in the second system was 0.6 mm. Maximum bar stress amounted to 578.6 MPa, that of clips was 136.99 MPa, and that of implants was 51.418 MPa. Clips cause smaller displacement of the overdenture when it is loaded but generate higher stress within the precision elements and implants compared to a denture retained only by a bar. Regardless of the shape of the precision element, small deformations occur that mainly affect the mucosa and the matrix.

Sizing and Topology Optimization of Trusses Using Genetic Algorithm

Genetic algorithms are a robust method for a solution of wide variety optimization problems. It explores a big space of design variables in order to find the best solution. From the point of view of a user, the algorithm requires the encoding of design variables into the form of strings and the procedure of optimization uses them for optimization. Here, for the structural engineer, it is crucial to find the form of objective function including the constraints of the task and also to avoid critical states during the solution of structural responses. This paper presents the use of genetic algorithm for solving truss structures. The use of genetic algorithm approach is shown on three cases of truss structures.

Feasibility of Reduced Ingot Hot-Top Height for the Cost-Effective Forging of Heavy Steel Ingots

Feasibility studies have been performed on ingots with reduced hot-top heights for the cost-effective hot forging of heavy ingots. The quality of the heavy ingots is generally affected by internal voids, which have been known to be accompanied by inclusions and segregation. To guarantee the expected mechanical performance of the forged products, these voids should be closed and eliminated during the hot open die forging process. Hence, to effectively control the internal voids, the optimum hot-top height and forging schedules need to be determined. In order to improve the utilization ratio of ingots, the ingot hot-top height needs to be minimized. To investigate the effect of the reduced hot-top height on the forged products, shaft and bar products have been manufactured via hot forging of ingots having various hot-top heights. From the operational results, the present work suggests effective forging processes to produce acceptable shaft and bar products using ingots having reduced hot tops. The mechanical properties of shop-floor products manufactured from ingots with reduced hot tops have also been measured and compared with those of conventional ingot products.

A Cohort Study of Edentulous Patients

Background and objectives: To compare the medium- to long-term mechanical behavior of overdentures with two different retention systems: overdentures with Locator® axial retention, and vertical insertion overdentures with bar retention, used to rehabilitate edentulous maxillar. Material and Methods: This prospective study assessed patients presenting complete maxillary edentulism, rehabilitated by means of implant-supported overdentures (n = 20), 10 with Locator® axial retention (ODA group) and 10 with overdentures on bars (ODB group). Patients also completed a questionnaire to determine their satisfaction with treatment. Results: The mean follow-up time in both groups was 11.4 years, with follow-up times in both groups ranging from 5 to 14 years. The ODA group suffered mechanical complications such as retention loss, need for nylon retention insert changes, resin fracture, and need for relining. In the ODB group, prosthetic dental wear, screw loosening, and complete prosthetic failure were more common. A total of 19 implants failed (23.8%); of these, 11 were in the ODA group (failure rate = 27.5%) and eight in the ODB group (failure rate = 20%). The patient satisfaction questionnaire obtained a mean score of 7.9 out of 10 in the ODA group, and 9.75 in the ODB group. Conclusions: in rehabilitations of edentulous maxillar by means of implant-supported overdentures, both the systems assessed were shown to be effective in the medium to long term. Patients expressed a high level of satisfaction with the treatments received.

A General Safety Assessment for Purified Food Ingredients Derived From Biotechnology Crops: Case Study of Brazilian Sugar and Beverages Produced From Insect-Protected Sugarcane

Insect-protected sugarcane that expresses Cry1Ab has been developed in Brazil. Analysis of trade information has shown that effectively all the sugarcane-derived Brazilian exports are raw or refined sugar and ethanol. The fact that raw and refined sugar are highly purified food ingredients, with no detectable transgenic protein, provides an interesting case study of a generalized safety assessment approach. In this study, both the theoretical protein intakes and safety assessments of Cry1Ab, Cry1Ac, NPTII, and Bar proteins used in insect-protected biotechnology crops were examined. The potential consumption of these proteins was examined using local market research data of average added sugar intakes in eight diverse and representative Brazilian raw and refined sugar export markets (Brazil, Canada, China, Indonesia, India, Japan, Russia, and the USA). The average sugar intakes, which ranged from 5.1 g of added sugar/person/day (India) to 126 g sugar/p/day (USA) were used to calculated possible human exposure. The theoretical protein intake estimates were carried out in the “Worst-case” scenario, assumed that 1 μg of newly-expressed protein is detected/g of raw or refined sugar; and the “Reasonable-case” scenario assumed 1 ng protein/g sugar. The “Worst-case” scenario was based on results of detailed studies of sugarcane processing in Brazil that showed that refined sugar contains less than 1 μg of total plant protein /g refined sugar. The “Reasonable-case” scenario was based on assumption that the expression levels in stalk of newly-expressed proteins were less than 0.1% of total stalk protein. Using these calculated protein intake values from the consumption of sugar, along with the accepted NOAEL levels of the four representative proteins we concluded that safety margins for the “Worst-case” scenario ranged from 6.9 × 10⁵ to 5.9 × 10⁷ and for the “Reasonable-case” scenario ranged from 6.9 × 10⁸ to 5.9 × 10¹⁰. These safety margins are very high due to the extremely low possible exposures and the high NOAELs for these non-toxic proteins. This generalized approach to the safety assessment of highly purified food ingredients like sugar illustrates that sugar processed from Brazilian GM varieties are safe for consumption in representative markets globally.

Locator Versus Bar Attachment Effect on the Retention and Stability of Implant-Retained Maxillary Overdenture: An In Vitro Study

PURPOSE

To compare retention and stability of Locator and bar attachments for implant-retained maxillary overdentures.

MATERIALS AND METHODS

Four implants were inserted into a maxillary acrylic resin model in canines and second premolar areas. Experimental overdentures were connected to the implants with bar (group I) or Locator (group II) attachments. Locators were divided into 3 subgroups according the degree of retention of the patrix nylon insert: Locator blue (group IIa), Locator pink (group IIb), and Locator transparent (group IIc). Retention (vertical dislodging) and stability (lateral, anterior, posterior dislodging) forces (N) were measured at the start of the experiment (initial retention) and after 540 cycles of denture insertion and removal (final retention).

RESULTS

The highest initial and final stability was recorded with group IIc, followed by group IIb and group IIa, and the lowest retention and stability was noted with group I. For all groups, the highest final retention and stability forces were noted with vertical dislodging, followed by posterior dislodging, anterior dislodging, and lateral dislodging. The highest loss of retention and stability was recorded with group I, followed by group IIc, group IIb, and group IIa.

CONCLUSION

Locator attachments are recommended to retain maxillary overdentures over Dolder bar attachments, as Locator attachments were associated with high retention and stability after wear simulation with minimal retention loss.

Long-term clinical and prosthetic outcomes of soft liner and clip attachments for bar/implant overdentures: a randomised controlled clinical trial

Long-term clinical and prosthetic outcomes of soft liner attachments for bar/implant overdentures were not sufficiently investigated. The aim of this trial was to evaluate clinical and prosthetic outcomes of resilient liner and clip attachments for bar/implant-retained mandibular overdenture after 7 years. Thirty edentulous male participants received two implants in the canine areas of the mandible. Three months later, implants were splinted with a resilient bar. Mandibular overdentures were connected to the bars with either clip (CR group, n = 15) or resilient liner (RR group, n = 15) attachments. Plaque index (PI), gingival index (GI), probing depth (PD), vertical bone loss (VBL), horizontal bone loss (HBLO) and prosthetic complications (PCs) were evaluated at denture delivery (T0), 6 (T_6m ), 12 (T1), 24 (T2), 36 (T3), 48 (T4), 60 (T5), 72 (T6) and 84 (T7) months after insertion. PI and GI increased significantly with time for CR and decreased significantly for RR (P < 0·001). PD increased at T1 (CR) and T6 m (RR) and then decreased thereafter (P < 0·05). VBL increased significantly with time in both groups (P < 0·005). HBLO increased at T2 (CR) and T1 (RR) and then decreased thereafter. CR recorded significant higher PI, GI, PD, VBLO and HBLO compared to RR at all observation times (P < 0·042). The survival rates were 96·6% and 100% for CR and RR after 7 years. The most common PCs for CR and RR were clip wears and separation of the resilient liner from the denture base, respectively. Within the limitations of this study, resilient liner attachments are recommended for bar/implant-retained mandibular overdentures than clip attachments in terms of peri-implant tissue health and prosthetic complications after 7 years.

Detection of Bar Transgenic Sugarcane with a Rapid and Visual Loop-Mediated Isothermal Amplification Assay

Genetic engineering offers an attractive alternative in sugarcane breeding for increasing cane and sugar yields as well as disease and insect resistance. Bar transgenic sugarcane employing the herbicide tolerance is a useful agronomical trait in weed control. In this study, a loop-mediated isothermal amplification (LAMP) assay for rapid detection of the bar gene in transgenic sugarcane has been developed and evaluated. A set of six primers was designed for LAMP-based amplification of the bar gene. The LAMP reaction conditions were optimized as follows: 5.25 mM of Mg(2+), 6:1 ratio of inner vs. outer primer, and 6.0 U of Bst DNA polymerase in a reaction volume of 25.0 μL. The detection limit of the recombinant plasmid 1Ac0229 was as low as 10 copies in the developed LAMP, which was 10-fold higher sensitive than that of conventional PCR. In 100 putative transgenic lines, the bar gene was detected in 100/100 cases (100%) by LAMP and 97/100 cases (97%) by conventional PCR, respectively. In conclusion, the developed LAMP assay is visual, rapid, sensitive, reliable, and cost-effective for detection of the bar specific transgenic sugarcane.

Co-transforming bar and CsALDH Genes Enhanced Resistance to Herbicide and Drought and Salt Stress in Transgenic Alfalfa (Medicago sativa L.)

Drought and high salinity are two major abiotic factors that restrict the productivity of alfalfa. By application of the Agrobacterium-mediated transformation method, an oxidative responsive gene, CsALDH12A1, from the desert grass Cleistogenes songorica together with the bar gene associated with herbicide resistance, were co-transformed into alfalfa (Medicago sativa L.). From the all 90 transformants, 16 were positive as screened by spraying 1 mL L(-1) 10% Basta solution and molecularly diagnosis using PCR. Real-time PCR analysis indicated that drought and salt stress induced high CsALDH expression in the leaves of the transgenic plants. The CsALDH expression levels under drought (15 d) and salt stress (200 mM NaCl) were 6.11 and 6.87 times higher than in the control plants, respectively. In comparison to the WT plants, no abnormal phenotypes were observed among the transgenic plants, which showed significant enhancement of tolerance to 15 d of drought and 10 d of salinity treatment. Evaluation of the physiological and biochemical indices during drought and salt stress of the transgenic plants revealed relatively lower Na(+) content and higher K(+) content in the leaves relative to the WT plants, a reduction of toxic on effects and maintenance of osmotic adjustment. In addition, the transgenic plants could maintain a higher relative water content level, higher shoot biomass, fewer changes in the photosystem, decreased membrane injury, and a lower level of osmotic stress. These results indicate that the co-expression of the introduced bar and CsALDH genes enhanced the herbicide, drought and salt tolerance of alfalfa and therefore can potentially be used as a novel genetic resource for the future breeding programs to develop new cultivars.

Chewing efficiency and electromyographic activity of masseter muscle with three designs of implant-supported mandibular overdentures. A cross-over study

PURPOSE

The aim of this study was to compare the effect of three designs for implant-supported mandibular overdenture on the chewing efficiency and electromyographic (EMG) activity of masseter muscles.

MATERIAL AND METHODS

Eighteen edentulous patients received new maxillary and mandibular dentures (control, CD) before implant placement. After using the dentures for 3 months, patients were randomly divided into six blocks (three patients/block) and received four implants in canine and first molar areas of the mandible. Following osseointegration period, new duplicate mandibular overdentures were successively connected to the implants with: (i) ball attachment on two implants (2BOD), (ii) bar attachment on two implants (2ROD), and (iii) bar attachments on four implants (4ROD) in a random order. Chewing efficiency was measured using chewing gum, and EMG was recorded during clenching (with or without food). Evaluations were made 3 months after using each of the following prostheses: CD, 2BOD, 2ROD, and 4ROD.

RESULTS

All implant-supported overdentures showed a significant increase in chewing efficiency and EMG values when compared to CD. These values increased significantly with 4ROD when compared to 2BOD or 2ROD prostheses. There was no significant difference in chewing efficiency and EMG between 2BOD and 2ROD prostheses.

CONCLUSION

Four-implant-supported overdentures seem to present a functional advantage vs. two-implant-supported overdentures, independent of the chosen attachment system.

Trans-iliac-sacral-iliac-bar procedure to treat insufficiency fractures of the sacrum

BACKGROUND

Osteoporosis is an increasing problem attributed to the greater longevity of the population and the incidence of fractures related to osteoporosis. The presence of osteoporotic bone, comorbidities, and functional status of the patient require adequate solutions to improve the clinical outcome of sacral insufficiency fractures. Conservative treatment by means of prolonged bed rest and analgesics are associated with increased risks and complications. A sacroplasty significantly improves the functional outcome. We describe the trans-iliac-sacral-iliac-bar (TISIB) procedure and our clinical experience to treat insufficiency fractures of the sacrum.

MATERIALS AND METHODS

The records of 19 consecutive patients with a mean age of 71.7 years (range: 57-82 years) who had been managed with a TISIB procedure from 2005 till 2007 were reviewed retrospectively. There were 15 females and 4 males. Predisposing factors for sacral insufficiency fractures were osteoporosis (n = 12, 63%), radiotherapy (n = 6, 32%), and rheumatoid arthritis (n =1). Diagnosis with a mean delay of 3.7 months was mainly made by CT. All patients were preoperatively and at follow-up assessed by means of the visual analogue score (VAS), analgesic consumption, and the ability to perform activities of daily living (ADLs) using a 5-point pain scale: 1, without pain; 2, mild pain; 3, moderate pain; 4, severe pain and, 5 unable to perform ADLs because of pain.

RESULTS

The average duration of postoperative follow-up was 9 months (range: 3-24.5 months). No neurological complications occurred during the surgery. A postoperative radiographic study showed a well-positioned bar in every case. The mean VAS improved 44.7 mm (preoperative: 67.8; at follow-up: 23.2). Fifteen patients (79%) consumed narcotic analgesics before surgery, and only one (5%) at follow-up; two patients (10%) consumed NSAIDS before surgery and three (15%) after. Two patients (10%) consumed minor analgesics before, and 11 (58%) after the procedure. Finally, four patients (21%) were not taking any analgesics at follow-up. Before surgery, 9 patients (47%) were able to perform ADLs with a pain score of 4; 6 (32%) with a score of 3, and 4 (21%) a score of 2. At follow-up 1 (5%) did have a score of 4; 1 (5%) a score of 3, 8 (42%) a score of 2 and 9 (47%) a pain score of 1.

CONCLUSION

A TISIB PROCEDURE RELIES ON THE PRINCIPLES OF FRACTURE TREATMENT: fracture stabilisation and compression. The incapacitating problem of an insufficiency fracture of the sacrum can be elegantly solved by means of this minimally invasive procedure. A near-immediate improvement is noticed when looking at the VAS score, analgesics consumption, and the ability to perform ADLs.

Transgenic plants of cassava (Manihot esculenta) with resistance to Basta obtained by Agrobacterium-mediated transformation

 Transgenic plants of cassava (Manihot esculenta) resistant to the herbicide Basta were obtained through Agrobacterium-mediated transformation. The plants also expressed the uidA gene and two were positive for PCR- and/or Southern-based detection of the nptII gene. Somatic-embryo-derived cotyledons were used as source of explants. A non-disarmed Agrobacterium strain (CIAT 1182) was used to transfer the genes of interest into cassava cultivar MPer183. Greenhouse tests of resistance to Basta (Hoechst) showed three plant lines with different levels of tolerance to the herbicide. Based on Southern tests of transgenesis, the transformation efficiency was 1%. The results constitute the first report of the bar gene conferring herbicide resistance to cassava plants.

Stable transformation of Eustoma grandiflorum by particle bombardment

Explants (7.5±2.5 mm) cut from stems and roots of 3-week-old Eustoma grandiflorum Grise, (lisianthus) cv. Glory White seedlings were bombarded with plasmid pBI221, which harbors the uidA gene encoding β-glucuronidase (GUS) driven by the cauliflower mosaic virus (CaMV) 35S promoter. More than 800 blue spots of GUS-expressing cells were observed per 90 explants. Explants bombarded with pARK22 harboring the bar gene encoding phosphinothricin acetyltransferase driven by the CaMV 35S promoter were selected for bialaphos resistance. Putative transgenic plants were obtained about 3 months after bombardment. Southern blot analysis of putative transgenic plants revealed the presence of the bar gene in their genome.

Harm Reduction as an Alcohol-Prevention Strategy

Harm-reduction programs, first developed in an attempt to mitigate the adverse consequences of illicit drug use, can be applied to alcohol-prevention programs as well. In fact, the movement toward harm reduction in illicit drug prevention may be closely paralleled by a similar trend in the alcohol-prevention field. Harm-reduction approaches to alcohol aim to diminish the negative consequences of intoxication (e.g., by using special glassware that breaks into fine particles instead of sharp pieces, thus reducing the chance of injury during pub fights). Such measures may receive increased attention as public support declines for restrictions on alcohol availability and new evidence emerges on the potential benefits of moderate alcohol consumption. In addition, analyses suggest that harm reduction may be an efficient approach, because it often focuses on minimizing heavy-drinking occasions, which predict drinking problems more strongly than level of consumption.