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100 kV is investigated as the operating voltage for single-particle electron cryomicroscopy (cryoEM). Reducing the electron energy from the current standard of 300 or 200 keV offers both cost savings and potentially improved imaging. The latter follows from recent measurements of radiation damage to biological specimens by high-energy electrons, which show that at lower energies there is an increased amount of information available per unit damage. For frozen hydrated specimens around 300 Šin thickness, the predicted optimal electron energy for imaging is 100 keV. Currently available electron cryomicroscopes in the 100-120 keV range are not optimized for cryoEM as they lack both the spatially coherent illumination needed for the high defocus used in cryoEM and imaging detectors optimized for 100 keV electrons. To demonstrate the potential of imaging at 100 kV, the voltage of a standard, commercial 200 kV field-emission gun (FEG) microscope was reduced to 100 kV and a side-entry cryoholder was used. As high-efficiency, large-area cameras are not currently available for 100 keV electrons, a commercial hybrid pixel camera designed for X-ray detection was attached to the camera chamber and was used for low-dose data collection. Using this configuration, five single-particle specimens were imaged: hepatitis B virus capsid, bacterial 70S ribosome, catalase, DNA protection during starvation protein and haemoglobin, ranging in size from 4.5 MDa to 64 kDa with corresponding diameters from 320 to 72 Å. These five data sets were used to reconstruct 3D structures with resolutions between 8.4 and 3.4 Å. Based on this work, the practical advantages and current technological limitations to single-particle cryoEM at 100 keV are considered. These results are also discussed in the context of future microscope development towards the goal of rapid, simple and widely available structure determination of any purified biological specimen.

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BACKGROUND: Limited data exist describing broodmare longevity and reproductive efficiency after surgical correction of ≥360 degree large colon volvulus (° LCV). OBJECTIVES: Compare career duration and foals delivered for broodmares before and after ≥360° LCV surgery. STUDY DESIGN: Retrospective case series. METHODS: Broodmares registered with The Jockey Club that had surgical correction of ≥360° LCV and survived to hospital discharge at Rood and Riddle Equine Hospital from 1 January 2000 to 31 December 2015 were included. Information was collected from the hospital's medical data base and The Jockey Club produce records about the mares' reproductive careers. Data were evaluated using parametric and nonparametric tests, P≤0.05. RESULTS: Mares that were bred but never foaled prior to surgery (n = 19) had shorter careers (mean ± standard deviation [s.d.]), 4.4 ± 4.5 years, and fewer foals, 3.1 ± 3.3, compared with mares that delivered ≥1 foal before surgery (n = 565), 10.4 ± 4.5 years and 7.4 ± 3.4 foals, respectively, P<0.001. Broodmares that delivered foals before surgery produced more foals in the years before surgery, 4.8 ± 3.0, than after surgery, 2.6 ± 2.4, P<0.001, and had longer breeding careers, 5.9 ± 3.8 vs. 4.5 ± 3.3 years before compared with after surgery, P<0.001. No significant differences in career length or number of foals delivered were detected for mares with a single compared with multiple LCV surgeries. Mares that were 3-11 years old at the time of surgery had significantly more foals after surgery compared with mares ≥12 years old, P<0.001, as expected. MAIN LIMITATIONS: Retrospective collection of data. CONCLUSIONS: Broodmares had productive careers following surgery for ≥360° LCV that were largely influenced by the mares' age at the time of surgery.

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Tendon injuries affect all levels of athletic horses and represent a significant loss to the equine industry. Accumulation of microdamage within the tendon architecture leads to formation of core lesions. Traditional approaches to tendon repair are based on an initial period of rest to limit the inflammatory process followed by a controlled reloading program designed to promote the maturation and linear arrangement of scar tissue within the lesion. However, these treatment protocols are inefficient, resulting in prolonged recovery periods and frequent recurrence. Current alternative therapies include the use of bone marrow-derived mesenchymal stem cells (BMSC) and a population of nucleated cells from adipose containing adipose-derived mesenchymal stem cells (AdMSC). Umbilical cord blood-derived stem cells (UCB) have recently received attention for their increased plasticity in vitro and potential as a therapeutic aid. Both BMSC and AdMSC require expansion in culture before implantation to obtain a pure stem cell population, limiting the time frame for implantation. Collected at parturition, UCB can be cryopreserved for future use. Furthermore, the low immunogenicity of the UCB population allows for allogeneic implantation. Current research indicates that BMSC, AdMSC, and UCB can differentiate into tenocyte-like cells in vitro, increasing expression of scleraxis, tenascin c, and extracellular matrix proteins. When implanted, BMSC and AdMSC engraft into the tendon and improve tendon architecture. However, treatment with these stem cells does not decrease recovery period. Furthermore, the resulting regeneration is not optimal, as the resulting tissue is still inferior to native tendon. Umbilical cord blood-derived stem cells may provide an alternate source of stem cells that promote improved regeneration of tendon tissue. A more naïve cell population, these cells may have a greater rate of engraftment as well as an increased ability to secrete bioactive factors and recruit additional reparative cells. Further work should clarify the role of distinct stem cell sources in the regenerating tendon and the need for a naïve or differentiated cell type for implantation.

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REASONS FOR PERFORMING STUDY: The main goal of feeding elite 3-day event horses is to deliver nutrients in optimal amounts to allow the horse to maximize its health and performance. However, improper nutritional management and/or physiological stressors related to intense training and competition may increase the risk of nutrition-associated disorders in these horses. An understanding of the nutrition-associated problems contributing to poor performance is critical to the health and welfare of the horse. OBJECTIVES: To characterize the nutrition-associated problems affecting top level 3-day event horses during 2008. METHODS: Contact information for riders competing in the 2 highest levels of 3-day eventing in 2008 was obtained from the United States Eventing Association. A survey containing 10 questions pertaining to participant demographics and nutrition-associated problems experienced by their horses was mailed and e-mailed to the 81 individuals fitting our criteria of living in USA and Canada. Data was collected in April and May 2009. RESULTS: Twenty-nine of 81 riders completed the survey (35.8%). Respondents rode a total of 45 horses in top level 3-day events in 2008. The top 5 nutrition-associated problems that horses faced at a significantly higher level than the other problems (P < 0.0001) were gastric ulcers (42.2%), joint problems (37.7%), decreased appetite (31.1%), weight loss (31.1%) and hyperexcitability (22.2%). There was no significant difference in frequency of problems between home and competition (P = 0.22). CONCLUSIONS: Horses competing at a high level of 3-day eventing in 2008 were at risk of reduced performance given the significant rate of gastric ulcers, decreased appetite and weight loss. Research addressing specific causes of and/or feeding management changes that would reduce the incidence of these problems in these horses is needed to ensure optimal health and performance.

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The structure-based design and progression of a screening lead to a 3nM factor VIIa/TF inhibitor with improved selectivity versus related enzymes is described.

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The development of potent and selective small molecule inhibitors of factor Xa is described.

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In July 1995, 40 Montana residents were identified with laboratory-confirmed Escherichia coli O157:H7 infection; 52 residents had bloody diarrhea without laboratory confirmation. The median age of those with laboratory-confirmed cases was 42 years (range, 4- 86); 58% were female. Thirteen patients were hospitalized, and 1 developed hemolytic-uremic syndrome. A case-control study showed that 19 (70%) of 27 patients but only 8 (17%) of 46 controls reported eating purchased (not home-grown) leaf lettuce before illness (matched odds ratio, 25.3; 95% confidence interval, 3.9-1065.6). Pulsed-field gel electrophoresis identified a common strain among 22 of 23 isolates tested. Implicated lettuce was traced to two sources: a local Montana farm and six farms in Washington State that shipped under the same label. This outbreak highlights the increasing importance of fresh produce as a vehicle in foodborne illness. Sanitary growing and handling procedures are necessary to prevent these infections.

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OBJECTIVE: To determine the effects of different prompted voiding schedules on urinary incontinence on a continence unit (CU) and the maintenance of benefits on normal nursing units. DESIGN: Multiphase study with both intra- and inter-subject comparisons. PARTICIPANTS: Subjects were 41 consenting incontinent nursing home residents. Based on clinical criteria, subjects were assigned to one of four treatment groups that varied as to the schedule of prompted voiding received. MEASUREMENT: The study used chart review, Katz ADL, and MMSE. Urologic status, self-initiated toileting, urine volumes voided, and incontinence assessed by pad/pants checks were measured by research nurses. Baseline pad check data were collected on residents' normal nursing units. Residents were transferred to the CU where baseline measurement was repeated, and the effects of different prompted voiding schedules were then assessed. Indigenous staff were trained to use prompted voiding, and nurse supervisors were instructed in special procedures for enhancing maintenance of the intervention. Residents were returned to their normal units and the maintenance of improvements in continence status was assessed at 2 weeks and 3 months post-CU discharge. RESULTS: One of the four groups showed significant improvement on the CU in response to the 2-hour schedule; two groups improved on the less intensive 3-hour schedule (P < 0.05). Two groups maintained this improvement on their normal nursing units (P < 0.05); one group showed a non-significant trend toward improvement. Self-initiated toileting decreased (P < 0.05) and volume voids in an appropriate receptacle increased (P < 0.05) during training. CONCLUSIONS: Prompted voiding is an effective treatment for urinary incontinence, and a less intensive 3-hour schedule may be superior to the standard 2-hour schedule for some residents. These improvements in dryness can be maintained by normal nursing home staff if formal staff management procedures are utilized by nurse supervisors.

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Continence improves from 44.7% dryness at baseline to 54.7% at the end of treatment, an improvement of 22%, or about one incontinent episode per day. Urinary incontinence is improved in cognitively impaired residents by augmenting the prompted voiding procedure with a bellpad. Bladder behavior changes with behavioral treatment strategies, because the volume voided into an appropriate receptacle increased an average of 26 mL per 2 hours. Reimbursement policies should not exclude treatment of the severely cognitively impaired nor the immobile in nursing homes.

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A 10-year review of 39 patients who underwent a superiorly based pharyngeal flap for severe velopharyngeal insufficiency was performed. The effectiveness of the operation, as scored by standardized preoperative and postoperative evaluations, was related to age at operation, type of defect, and duration of velopharyngeal inadequacy. There was no statistical difference between those who were under the age of 6 years (100 percent were improved) at the time of the operation versus those 6 years and older (74 percent improved). Likewise, there was no difference between those patients who received an early flap (92 percent were improved) versus those who received a flap 2 or more years after initial palatorrhaphy (90 percent were improved). The type of palatal defect also was not a significant factor, and none of the patients exhibited a postoperative decrease in function (p less than or equal to 0.001). The operation offered reliable salvage of velopharyngeal competency regardless of the above-mentioned factors.

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The management and treatment of incontinence represent two interrelated areas--providing enough providers of care and describing the types of management and treatment options available to the incontinent patient. This article has stressed that adequate staffing underlies any successful program of continence management and treatment. In addition, many options for the management and treatment of incontinence in the elderly have been presented. Of importance are the specific nursing implications that will make many continence protocols successful. These guidelines can provide the basis for planning patient care through the nursing process. This article has also addressed management and treatment strategies for incontinence that not only improve incontinence in patients but may cure it. These include behavioral management strategies which nurses should be encouraged to use in treating incontinent patients in the community. These same behavioral management strategies are being studied in inpatient settings, and the results indicate that nurses in inpatient settings and long-term care facilities should implement behavioral treatment programs for incontinent patients.

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The nude mouse has been successfully employed for the propagation of human tumors, without the need for immunosuppression. In light of the limited data on embryonic gene expression in such tumors, we undertook a study of fetal isoenzyme expression during tumor growth. HeLa TCRC-1 which has been shown to produce the placental Regan isoenzyme was used in these studies. The isoenzyme produced by these cells in culture is initially replaced by an isoenzyme referred to as chorionic. In the later stages of tumor growth, the so-called oncoamniotic (FL) isoenzyme then becomes the dominant enzyme form. The chorionic isoenzyme is produced by the early chorionic membranes of the developing conceptus, while the oncoamniotic (FL) isoenzyme is most similar to that found in the fetal human intestine. The alteration in the expression of fetal isoenzymes in tumors growing in the nude mouse is similar to that seen in the immunosuppressed rat and hamster host animals, indicating that the phenomenon is not related to immunosuppression per se.

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We have grown 7 bona fide non-HeLa contaminated cell lines in the cheek pouch of immunosuppressed adult hamsters. Six of the cell lines studied produced or continued to express the chorionic form of alkaline phosphatase under these conditions. The Regan isoenzyme produced in culture by the J82, T24, HCT-8, and COLO 16 cell lines disappeared in vivo with a concomitant appearance of the chorionic isoenzyme. The other cell lines, however, maintained the expression of the Regan isoenzyme when grown as a xenograft: the C41 line produced the Regan isoenzyme in culture, and continued to do so in vivo, while the BeWo cells, which synthesized the chorionic enzyme in culture were induced by in vivo growth to produce both the Regan and chorionic isoenzymes. No expression of the oncoamniotic (FL) isoenzyme was observed in any of the lines studied. Our results indicate a convergence of human tumor xenografts with respect to the production of the chorionic form of alkaline phosphatase. Furthermore, the loss of production of the Regan isoenzyme was seen in most, but not all cell lines studied. Since the oncoamniotic (FL) isoenzyme was only observed by HeLa cells growing as a xenograft, the expression of this enzyme form may be a HeLa specific phenomenon. We must now look to the regulation of the chorionic isoenzyme as the most promising avenue of approach to understanding the biological significance of altered isoenzyme expression in human tumor xenografts.

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