Molecular Diversity of Terpene Synthases in the Liverwort Marchantia polymorpha.

Marchantia polymorpha is a basal terrestrial land plant, which like most liverworts accumulates structurally diverse terpenes believed to serve in deterring disease and herbivory. Previous studies have suggested that the mevalonate and methylerythritol phosphate pathways, present in evolutionarily diverged plants, are also operative in liverworts. However, the genes and enzymes responsible for the chemical diversity of terpenes have yet to be described. In this study, we resorted to a HMMER search tool to identify 17 putative terpene synthase genes from M. polymorpha transcriptomes. Functional characterization identified four diterpene synthase genes phylogenetically related to those found in diverged plants and nine rather unusual monoterpene and sesquiterpene synthase-like genes. The presence of separate monofunctional diterpene synthases for ent-copalyl diphosphate and ent-kaurene biosynthesis is similar to orthologs found in vascular plants, pushing the date of the underlying gene duplication and neofunctionalization of the ancestral diterpene synthase gene family to >400 million years ago. By contrast, the mono- and sesquiterpene synthases represent a distinct class of enzymes, not related to previously described plant terpene synthases and only distantly so to microbial-type terpene synthases. The absence of a Mg2+ binding, aspartate-rich, DDXXD motif places these enzymes in a noncanonical family of terpene synthases.

The Causal Effect of Student Mobility on Standardized Test Performance: A Case Study with Possible Implications for Accountability Mandates within the Elementary and Secondary Education Act.

This paper presents a limited case study examining the causal inference of student mobility on standardized test performance, within one middle-class high school in suburban Connecticut. Administrative data were used from a district public high school enrolling 319 10th graders in 2010. Propensity score methods were used to estimate the causal effect of student mobility on Math, Science, Reading, and Writing portions of the Connecticut Academic Performance Test (CAPT), after matching mobile vs. stable students on gender, race/ethnicity, eligibility for free/reduced lunches, and special education status. Analyses showed that mobility was associated with lower performance in the CAPT Writing exam. Follow-up analyses revealed that this trend was only significant among those who were ineligible for free/reduced lunches, but not among eligible students. Additionally, mobile students who were ineligible for free/reduced lunches had lower performance in the CAPT Science exam according to some analyses. Large numbers of students transferring into a school district may adversely affect standardized test performance. This is especially relevant for policies that affect student mobility in schools, given the accountability measures in the No Child Left Behind that are currently being re-considered in the recent Every Student Succeeds Act.

Effect of SORT1, APOB and APOE polymorphisms on LDL-C and coronary heart disease in Pakistani subjects and their comparison with Northwick Park Heart Study II.

BACKGROUND: Many SNPs have been identified in genes regulating LDL-C metabolism, but whether their influence is similar in subjects from different ethnicities is unclear. Effect of 4 such SNPs on LDL-C and coronary heart disease (CHD) was examined in Pakistani subjects and was compared with middle aged UK men from Northwick Park Heart Study II (NPHSII). METHODS: One thousand nine hundred sixty-five (1770 non CHD, 195 CHD) UK and 623 (219 non CHD, 404 CHD) Pakistani subjects were enrolled in the study. The SNPs SORT1 rs646776, APOB rs1042031 and APOE rs429358, rs7412 were genotyped by TaqMan/KASPar technique and their gene score was calculated. LDL-C was calculated by Friedewald equation, results were analyzed using SPSS. RESULTS: Allele frequencies were significantly different (p= <0.05) between UK and Pakistani subjects. However, the SNPs were associated with LDL-C in both groups. In UK non CHD, UK CHD, Pakistani non CHD and Pakistani CHD respectively, for rs646776, per risk allele increase in LDL-C(mmol/l) was 0.18(0.04), 0.06(0.11), 0.15(0.04) and 0.27(0.06) respectively. For rs1042031, per risk allele increase in LDL-C in four groups was 0.11(0.04), 0.04(0.14), 0.15(0.06) and 0.25(0.09) respectively. For APOE genotypes, compared to Ɛ3, each Ɛ2 decreased LDL-C by 0.11(0.06), 0.07(0.15), 0.20(0.08) and 0.38(0.09), while each Ɛ4 increased LDL-C by 0.43(0.06), 0.39(0.21), 0.19(0.11) and 0.39(0.14) respectively. Overall gene score explained a considerable proportion of sample variance in four groups (3.8%, 1.26% 13.7% and 12.3%). Gene score in both non-CHD groups was significantly lower than CHD subjects. CONCLUSIONS: The SNPs show a dose response association with LDL-C levels and risk of CHD in both populations.

Adolescent risk factors for purging in young women: findings from the national longitudinal study of adolescent health.

BACKGROUND: There exists a dearth of prospective adolescent eating disorder studies with samples that are large enough to detect small or medium sized effects for risk factors, that are generalizable to the broader population, and that follow adolescents long enough to fully capture the period of development when the risk of eating disorder symptoms occurring is highest. As a result, the purpose of this study was to examine psychosocial risk factors for purging for weight control in a nationally representative sample of adolescents. Data were extracted from the restricted-use data sets of the National Longitudinal Study of Adolescent Health (Waves I-III), selecting females with valid demographic and purging information (N = 5,670). RESULTS: The prevalence of purging was 0.88% at Wave II and 0.56% at Wave III. In multivariable multinomial logistic regressions, purging at Wave II was predicted by parental poverty and low levels of self-esteem at Wave I; purging at Wave III was predicted by body mass index and the frequency of delinquent behaviors at Wave I. CONCLUSIONS: Individuals with high body mass index, individuals with low self-esteem, and individuals in families experiencing economic hardship appear specifically at risk for the development of purging behaviors in later years and may benefit from more targeted prevention efforts.

Prevalence and correlates of unhealthy weight control behaviors: findings from the national longitudinal study of adolescent health.

BACKGROUND: A recent study examined the prevalence, clinical correlates, age trends, and stability of unhealthy weight control behaviors (UWCB; purging and diet pill use) in a nationally representative sample of Norwegian boys and girls. The purpose of this study was to provide similar, comparative analyses for a nationally representative sample of American youth. METHODS: Data were extracted from the restricted use data files of survey Waves I, II, and III of the National Longitudinal Study of Adolescent Health (Add Health), selecting all participants who at Wave I had provided information on age, sex, and UWCB. Using UWCB information, three groups were created (purging, diet pill use, and no recent UWCB "controls") and compared on indicators of adverse health or mental health. RESULTS: Girls consistently were more likely than boys to report UWCB. UWCB were significantly associated with higher body mass index, self-perception of being overweight, low self-esteem, depression, and delinquency. Prevalence estimates for purging remained relatively constant across the three survey waves; in contrast, diet pill use was especially common at Wave III. CONCLUSIONS: Age trends, gender differences, and clinical correlates of change in the likelihood of UWCB between Waves I-III were all identified in analyses comparing purging and diet pill use in American adolescents. Females and older adolescents were specifically more likely to engage in pill use than purging, and individuals with increased weight dissatisfaction, a history of delinquent behaviors, more depression symptoms, or lower self-esteem were more likely to engage in an unhealthy weight control behavior over time. While the Norwegian study found that prevalence of purging was lower among young adult participants, our results suggested that there were no significant differences in prevalence between age groups.

Aerosol and nasal delivery of vaccines and antiviral drugs against seasonal and pandemic influenza.

Influenza is primarily a respiratory tract infection involving the exacerbation and inflammation of the respiratory tract, which can progress to life-threatening pneumonia, hypercytokinemia, edema, acute lung injury, respiratory failure and death. Viral mutations and drug resistance are the leading challenges in influenza prevention and treatment. Aerosol inhalation provides rapid availability and sustained therapeutic levels of antiviral drugs in the respiratory tract, without causing a systemic burden to unaffected tissues and organs. Furthermore, aerosol delivery enhances the bioavailability of antiviral drugs with poor oral adsorption. Nasal spray delivery of vaccines provides a safe and needle-free means of vaccination, and contains live-attenuated virus that induces mucosal immunity and provides long-lasting immunity relative to injectable inactivated vaccines. Since influenza is a disease with respiratory clinical manifestations, specific delivery of antiviral drugs or vaccines to the respiratory tract may represent a safe and effective approach to combat influenza.

Arsenic in the hair of the individuals in Santana-AP-Brazil: significance of residence location.

The concentration of arsenic in the hair of the individuals living in Santana city was measured. 121 donors in urban and the periphery area were studied. The periphery of the city shows the highest levels of arsenic (5.94 +/- 6.54 mg kg(-1) - mean; 0.27-23.85 mg kg(-1)). 47.83% in the urban area showed arsenic concentrations of less than 1.00 mg kg(-1), while in the periphery only 11.22% had results below this value. The results showing the influence of residence location. The Principal Component Analysis showed that the variable residence location were responsible for the correct formation of the periphery group.

Healthcare Waste Management in Clinics in a Rural Health District in Kwazulu-Natal

The handling of healthcare waste (HCW) was investigated in 30 rural healthcare facilities in KwaZulu-Natal. Using a semi-structured questionnaire; interviews were carried out with the person in charge of the facility and observations were made to establish current practices in sorting; handling and disposal of HCW. It was found that improper sorting and management of HCW occurred on most sites with implications for cost; infection control and education. It is imperative therefore that improved HCW management measures be implemented and that healthcare facility staff receive appropriate and repeated training to ensure minimising risk

Comparison of tensile strength of resorbable plating systems used in monocortical mandible angle osteotomy repair.

OBJECTIVE: To determine the usefulness of resorbable plating systems in load-bearing applications of the mandible and the location of critical failure. METHODS: An osteotomy was created in 24 fresh cadaveric mandibles at the angle and fixated by the Champy technique with similar resorbable craniofacial plating systems from 4 manufacturers. Each mandible was held rigid as a material test system applied a downward force anteriorly. The critical tolerance was measured and the type of failure was noted. RESULTS: Critical failure occurred at forces from 34.6 to 137.8 N. We found a statistically significant difference between the plating groups (P<.001 for all comparisons). The point of failure was almost uniformly at the plate. CONCLUSIONS: Critical failure was overwhelmingly due to rupture of the plate rather than to stripping or shearing of the screws as had been strongly expected. We found differences in plate strengths for this particular application and did not evaluate their respective long-term resorptive properties. We do not advocate that single resorbable plate fixation be the sole means of mandible angle fracture fixation, regardless of the plating system used.

Long-term blockade of angiotensin AT1 receptors increases survival of obese Zucker rats.

Despite the well-documented effect of irbesartan, an angiotensin AT1 receptor antagonist, on diabetic nephropathy, its effect on mortality related to multiple metabolic risk factors is unknown. To address this question, obese fa/fa Zucker rats were submitted to a 13-month treatment by irbesartan (30 mg/kg/day p.o.). Vehicle-treated obese fa/fa Zucker rats exhibited an important mortality (72%), which was markedly reduced by irbesartan (22%, P<0.05). Mortality in control lean fa/+ rats attained 12%. Irbesartan diminished the elevation in urinary protein excretion, plasma creatinine and urea nitrogen levels, and reduced the extent of glomerular and tubulo-interstitial lesions together with a reduction of urinary monocyte chemoattractant protein-1 excretion in fa/fa Zucker rats. Irbesartan treatment prevented the rise in plasma total cholesterol, triglycerides and glucose levels, and partially corrected low-density lipoprotein/high-density lipoprotein (LDL/HDL) cholesterol ratio in fa/fa Zucker rats. Therefore, prolonged irbesartan treatment preserves renal function and metabolic profile, and substantially increases survival in obese fa/fa Zucker rats.

A comparison of resistance to fracture among four commercially available forms of hydroxyapatite cement.

Hydroxyapatite cement is a relatively new biomaterial that has found widespread use in craniomaxillofacial surgery. Despite its common usage, complication rates as high as 32% have been reported. When failed implants are removed, implant fracture has been cited as a potential cause of failure. The purpose of this study was to evaluate resistance to fracture among 4 commercially available hydroxyapatite cement formulations. The materials tested included Norian Craniofacial Repair System (carbonated apatite cement) (AO North America, Devon, PA), Norian CRS Fast Set Putty (carbonated apatite cement) (AO North America), BoneSource (hydroxyapatite cement) (Stryker Leibinger, Portage, MI), and Mimix (hydroxyapatite cement) (Walter Lorenz Surgical, Inc, Jacksonville, FL). To ensure consistency, all materials were embedded in acrylic wells. Each material was placed into a well 2.54 cm in diameter and 0.953 cm in thickness. The materials were prepared per manufacturer specifications. All materials were incubated at 37.0 degrees C, in 6% CO2, 100% humidity for 36 hours. Using the Bionix MTS Test System, a 12-mm-diameter probe applied incremental force to the center of the disk at a rate of 0.1 mm per second. The transmitted force was measured using a Bionix MTS Axial-Torsional Load Transducer for each disk. The force which resulted in fracture was recorded for each material. Ten disks of each material were processed by this method, for a total of 40 disks. The significance of resistance to fracture for the 4 compounds was analyzed using 1-way analysis of variance with post hoc Scheffe method. Mean fracture force with related P values was plotted for direct comparison of group outcomes. Material type contributed significantly to variance in fracture force for the biomaterials studied. Norian CRS required the greatest mean fracture force (1385 N, SD+/-292 N), followed by Norian CRS Fast Set Putty (1143 N, SD+/-193 N). Mimix required a mean fracture force of 740 N, SD+/-79 N. BoneSource required a mean fracture force of 558 N, SD+/-150 N. Mimix and BoneSource required significantly less force for fracture when compared with Norian CRS and Fast Set Putty (P<0.01). Comparisons of fracture load resistance between 4 commonly used bone substitute materials have not been previously reported. Increasing biomaterial strength may reduce complications resulting from reinjury to cranioplasty sites. In this model, Norian CRS and Norian CRS Fast Set Putty demonstrated a significantly greater resistance to fracture when compared with BoneSource and Mimix.

Comparison of bacterial inoculation and transcutaneous oxygen tension in the rabbit S1 perforator and latissimus dorsi musculocutaneous flaps.

Muscle and musculocutaneous flaps have been used reliably in reconstruction of soft-tissue defects for many years. Previous experimental studies have shown musculocutaneous flaps to be superior to the random pattern and fasciocutaneous flaps in the management of infected wounds. Over the past decade, perforator flaps have gained acceptance as alternative methods of reconstruction in the clinical setting that can decrease donor-site morbidity and hospital stay, and increase patient satisfaction. The authors theorized that perforator flaps may be able to handle infected wounds better than random pattern and fasciocutaneous flaps because their blood supply is essentially the same as many of their musculocutaneous counterparts. The goal of this study was to compare the S1 perforator-based skin flap and latissimus dorsi musculocutaneous flap in the dorsal flank of the rabbit with the introduction of bacteria to simulate both superficial and deep wound infection. Measurements of oxygen tension and regional perfusion index were performed on both types of flaps to ascertain their viability and capacity to heal. The authors found no statistical significance between latissimus dorsi musculocutaneous and S1 perforator flaps in the rabbit with respect to superficial and deep wound infections. The regional perfusion index was calculated for postoperative days 1, 2, and 4. No statistically significant difference between the two flaps using the regional perfusion index could be identified. Additionally, regional perfusion for both types of flaps was greater than 0.6, indicating that their capacity to heal wounds is similar.

A comparison of combinations of titanium and resorbable plating systems for repair of isolated zygomatic fractures in the adult: a quantitative biomechanical study.

Multiple studies have sought to determine the postreduction stability of internal fixation in zygomaticomaxillary complex (ZMC) fractures. Three-point fixation with titanium miniplates is increasingly recommended to repair these injuries. Use of bioresorbable plates has been suggested to eliminate potential postoperative hardware complications. By quantitatively comparing different combinations of titanium and resorbable plating systems, this study attempts to demonstrate which combinations will provide stable fixation of the fractured ZMC. Osteotomies were performed on 40 zygomas in 20 fresh-frozen cadaver skulls, simulating noncomminuted ZMC fractures. The control group (group 0) consisted of titanium plates at the zygomaticofrontal (ZF) suture, infraorbital rim (IOR), and zygomaticomaxillary buttress (ZMB). Group 1 consisted of titanium plates at the ZF and IOR, and a resorbable plate at the ZMB. Group 2 used a titanium plate at the ZF, and resorbable plates at the IOR and ZMB. Group 3 consisted of resorbable plates at the ZF, IOR, and ZMB. A mechanical test system was used to apply loads in the vectorial direction of the masseter. Critical forces and patterns of hardware failure were recorded. Group 0 failed at a mean force of 589 +/- 146 N (60 kg). Group 1 failed at a mean force of 507 +/- 124 N (52 kg). No statistically significant differences between groups 0 and 1 were found. The mean force required for failure in groups 2 and 3 was lower. Differences in the force required for failure between groups 2 and 3 and the control group was significant (P <0.05). Failure patterns were analyzed. The ZF plate tended to stretch predominantly in groups 1, 2, and 3, whereas it tended to break in group 0 (P = 0.005). The IOR plate demonstrated predictable screw failure in groups 2 and 3 (P = 0.007). For group 0, the ZF was the site of the majority of critical failures. For groups 2 and 3, the IOR was almost invariably the site of critical failure (P = 0.004). At the ZMB, there was no significant association between failure modes and it was rarely the site of critical failure, regardless of the method of fixation. However, the strength of fixation was proportional to the number of titanium plates used. Overall, the method of fixation significantly affected the force required for mechanical failure of ZMC fractures (P <0.0001). The presence of teeth significantly increases the force required for implant failure in ZMC fracture fixation when combinations of plates are used (P = 0.038). All combinations of titanium and resorbable plates may be sufficient to overcome the displacing forces produced by the masseter and may be used for internal fixation of isolated ZMC fractures in the adult.

Diagnosing and treating nasal septal perforations.

The authors present a comprehensive treatment guide to nasal septal perforations. Successful surgical repair requires vascularized tissue flaps, interpositional tissue scaffolding, and tension-free closure. However, surgical techniques vary with the size of the defect, and there is no single universally effective procedure.

The thoracodorsal artery perforator-scapular osteocutaneous (TDAP-SOC) flap for reconstruction of palatal and maxillary defects.

Despite technical advances over the past 3 decades, subtotal, total, and extended total maxillectomy defects remain challenging reconstructive problems. In particular, postoncologic resection of the maxilla results in complex 3-dimensional defects of the midface, which cause severe functional and esthetic deformities. Such defects generally require composite tissue flaps for reconstruction. Rebuilding the palate and maxilla is especially challenging because it requires reconstitution of the facial buttresses, occlusion, replacement of bony hard palate, and the thin intraoral and intranasal lining which normally constitute the soft palate. Various methods of reconstruction have been applied to this area in search of an ideal soft tissue-bone flap to restore the bony framework of the maxilla and palate while providing an internal lining. Osteocutaneous and osteomuscular flaps such originating from the scapular, iliac, peroneal, and radial vascular systems have been attempted with good success. We devised an osteocutaneous flap based on the scapular vascular system, which provided bone and soft tissue to successfully reconstruct the palate and maxilla in 2 patients. The skin paddle received its blood supply from the major perforating vessels of the thoracodorsal artery, and the scapular bone was nourished by the angular vessels. Although free tissue transfer using thoracodorsal perforator flaps has been described, this flap has not been previously reported in the literature as an osteocutaneous tissue transfer. With the use of rigid fixation, excellent results have been obtained with this technique for palatal and maxillary reconstruction.

Advantages of perforator flaps in reconstruction of complex defects of the head and neck.

Microsurgical transfer of vascularized tissue during the past three decades has allowed highly complicated postoncologic defects in the head and neck region to be reconstructed. Recently, perforator flaps have been used to reduce postoperative pain, shorten hospital stay, and lessen donor-site complications. These flaps are offsprings of previously known musculocutaneous and fasciocutaneous flaps and are harvested with preservation of the underlying muscular and fascial structures. The vascularized skin and soft-tissue envelope is supplied by perforating branches from the parent vessel. Less is known about the performance of these flaps in the head and neck region. During a 4-year period, 22 patients at our institution underwent reconstruction of the head and neck region with deep inferior epigastric perforator (DIEP) or thoracodorsal artery perforator (TDAP) flaps. All but one of the flaps survived. Advantages noted include: (1) longer vascular pedicles, (2) less postoperative pain, (3) less donor-site deformity, (4) improved aesthetic outcome, (5)potential for a neurosensory flap, (6) potential for an osteocutaneous flap, and (7) ease of postoperative radiologic follow-up. The DIEP flap can be harvested concurrent with oncologic resection, with the patient in the supine position. The TDAP flap is dissected with the patient in the decubitus position, creating an additional step to change operative position, and separates extirpative and reconstructive stages.

Simultaneous bilateral breast reconstruction with superior gluteal artery perforator (SGAP) flaps.

The superior gluteal artery perforator (SGAP) flap is a useful technique for restoration of the breast after mastectomy. If appropriately planned, the soft-tissue envelope supplied by the superior gluteal artery perforator vessels can be harvested with minimal donor site morbidity and often results in a highly esthetic restoration of the breasts. Dissection of the flap is performed with complete preservation of gluteus maximus muscle function. The resulting vascular pedicle obtained via dissection through the muscle is longer than that of gluteal musculocutaneous flaps and affords the surgeon the luxury of avoiding vein grafts in the anastomotic phase of surgery. Despite these advantages, use of the SGAP flap is not popular among reconstructive surgeons. Many practitioners are not familiar with the vascular anatomy of the gluteal area and may not be comfortable with the dissection of the parent vessels or lack the desire to practice microsurgery. On the other hand, our group has reported the largest experience to date with this method of breast reconstruction and has found the SGAP flap to be a reliable and safe method of autologous breast restoration in unilateral absence of the breast. Although the indications to perform single-stage gluteal tissue transplantation for bilateral breast restoration are uncommon, they do occasionally arise in clinical practice. We have carried out concurrent bilateral breast reconstruction using SGAP flaps on 6 patients with acceptable overall morbidity. All flaps went on to survive and resulted in highly esthetic restorations of the breast. Though a challenging undertaking, in-unison transfer of bilateral SGAP flaps serves as a useful option for a subset of patients desiring 1-stage bilateral breast reconstruction.

Variability of the postauricular muscle complex: analysis of 40 hemicadaver dissections.

BACKGROUND: The postauricular area is often explored by reconstructive and otologic surgeons. We previously reported on the use of postauricular tissues as a graft for wrapping hydroxyapatite implants in orbital reconstruction. This procedure reduced the incidence of implant exposure, while achieving acceptable cosmetic results. Although much is known about the postauricular area, muscle and fascial relationships and potential variations in anatomy remain ill defined. OBJECTIVES: To identify and analyze variations in the patterns of the postauricular muscle complex (PMC) and to study the relationships of the fascial contributions from the components that make up the PMC. METHODS: Dissections were performed using 40 fresh specimens. Muscular and fascial components of the PMC were dissected, analyzed, and photographed. RESULTS: The PMC receives contributions from the occipitalis and trapezius muscles, the deep temporal and sternocleidomastoid fasciae, and the superior and posterior auricular and platysma muscles. Major contributors to the PMC were present in every specimen. Minor contributors were more variable in their presence and contributions. The posterior auricular muscle was identified as having several muscle bundles in 1 specimen and absent in 2 specimens (5%). The occipitalis fascia was seen to insert superior to the auricle and to blend with the deep temporal fascia in 3 cases (7%). The platysma muscle contributed to the PMC in 8 cases (20%). CONCLUSIONS: This study demonstrated important variations in the presence and contributions of 7 previously known muscular structures and their role in forming the PMC. Seven distinct patterns are identified, and the potential clinical implications of these anatomical variations are illustrated.

Use of the deep inferior epigastric perforator flap in a 15-month-old boy after resection of lymphatic malformation.

Lymphatic malformations are benign tumors that arise from congenital defects of the lymphatic system. Despite the fact that all lymphatic malformations develop embryologically, their presence may not be detected until the tumor enlarges from hemorrhage or infection. Typical of these tumors is a slow-growing, asymptomatic phase with the potential for rapid and massive expansion and a tendency to infiltrate into surrounding tissues. These tumors are associated with a high rate of recurrence, especially with incomplete excisions. To minimize the chance of recurrence, a complete resection of a groin microcystic lymphatic malformation was performed on this 15-month-old boy, creating a significant defect in the upper thigh. Immediate coverage was felt to be the best option for reducing any associated morbidity. We used a skin-soft tissue flap supplied by perforators of the deep inferior epigastric artery to repair the wound. Using this technique, the musculofascial structures in the abdominal wall were completely spared, and the skin and fat were transferred on a vascular leash to the desired location. The donor site was closed by approximating the fascial edges without tension. The defect on the thigh was filled with tissue of similar thickness and characteristics, avoiding potential contour irregularities and color mismatch. The deep inferior epigastric perforator (DIEP) flap is a useful option for groin defects and can be applied safely in the pediatric population.