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In recent years several interspecific hybrids have been reported in the plant pathogenic oomycete genus Phytophthora . Due to the large genotypic and phenotypic changes, these hybrids might have broader or more limited host ranges compared with their parental species. It is crucial to understand the host range of Phytophthora hybrids to minimize the economic losses caused by their infection. The potential host range of four hybrids belonging to Clade 8a of the Phytophthora phylogenetic tree was investigated in this study. Thirty species of herbaceous plants as well as eight species of woody plants were inoculated and monitored for any symptom of infection. In addition, the detached twigs of 32 tree species, fruits of six plant species, tubers of potato, and roots of carrot and sugar beet were investigated for susceptibility to these hybrids. Almost all hybrids caused severe rot on all tested fruits, tubers, and roots, although different isolates showed different pathogenicity on detached tree twigs. All hybrids tested had a different host range compared with their parental species: they were able to infect plants outside the host range of their parents, infect hosts of both parental species, although these parents did not have overlapping hosts, or, in some cases, they were not able to infect hosts infected by the parents.

In recent years several interspecific hybrids have been reported in the plant pathogenic oomycete genus Phytophthora . Due to the large genotypic and phenotypic changes, these hybrids might have broader or more limited host ranges compared with their parental species. It is crucial to understand the host range of Phytophthora hybrids to minimize the economic losses caused by their infection. The potential host range of four hybrids belonging to Clade 8a of the Phytophthora phylogenetic tree was investigated in this study. Thirty species of herbaceous plants as well as eight species of woody plants were inoculated and monitored for any symptom of infection. In addition, the detached twigs of 32 tree species, fruits of six plant species, tubers of potato, and roots of carrot and sugar beet were investigated for susceptibility to these hybrids. Almost all hybrids caused severe rot on all tested fruits, tubers, and roots, although different isolates showed different pathogenicity on detached tree twigs. All hybrids tested had a different host range compared with their parental species: they were able to infect plants outside the host range of their parents, infect hosts of both parental species, although these parents did not have overlapping hosts, or, in some cases, they were not able to infect hosts infected by the parents.

Background: Ileostomy reversals are commonly performed procedures after colon and rectal operations. Laparoscopic ileostomy reversal (LIR) with lysis of adhesions has potential benefits over conventional open surgery. The aim of this study was to compare outcomes of laparoscopic and open ileostomy reversal. Methods: 133 consecutive patients undergoing ileostomy reversal at our institution between June 2009 and August 2013 were analyzed using a retrospective database. The group comprised 53 laparoscopic cases and 80 open cases, performed by four surgeons at a single center. The data were analyzed for patient demographics, operative characteristics, postoperative outcomes, and 30-day morbidity and mortality. Results: The two groups had comparable mean age, gender distribution, ASA scores, and BMI. The laparoscopic group had a significantly longer duration of surgery compared to the open reversal group (109 versus 93 min, p < 0.05). However, this group underwent more lysis of adhesions (60.4 % versus 26.3 %, p < 0.01) as well as concurrent stoma site mesh reinforcement (32.1 % versus 6.3 %, p < 0.01). In the laparoscopy group, 20.7 % of patients underwent intra-corporeal ileo-ileal anastomosis. There were no significant differences between the laparoscopic and open groups with regard to estimated blood loss (31 versus 40 ml, respectively) or mean length of stay (5.3 vs. 5.7 days, respectively). The rates of overall 30-day morbidity (16.9 % for laparoscopic vs. 21.3 % for open) as well as rates of specific complications were equivalent between groups. 30-day mortalities were not noted in either group. Conclusion: LIR is safe and effective with low perioperative morbidity and mortality. The use of laparoscopy as an option in terms of concomitant hernia repair and lysis of adhesions may be considered in selected patients.

Background: Ileostomy reversals are commonly performed procedures after colon and rectal operations. Laparoscopic ileostomy reversal (LIR) with lysis of adhesions has potential benefits over conventional open surgery. The aim of this study was to compare outcomes of laparoscopic and open ileostomy reversal. Methods: 133 consecutive patients undergoing ileostomy reversal at our institution between June 2009 and August 2013 were analyzed using a retrospective database. The group comprised 53 laparoscopic cases and 80 open cases, performed by four surgeons at a single center. The data were analyzed for patient demographics, operative characteristics, postoperative outcomes, and 30-day morbidity and mortality. Results: The two groups had comparable mean age, gender distribution, ASA scores, and BMI. The laparoscopic group had a significantly longer duration of surgery compared to the open reversal group (109 versus 93 min, p < 0.05). However, this group underwent more lysis of adhesions (60.4 % versus 26.3 %, p < 0.01) as well as concurrent stoma site mesh reinforcement (32.1 % versus 6.3 %, p < 0.01). In the laparoscopy group, 20.7 % of patients underwent intra-corporeal ileo-ileal anastomosis. There were no significant differences between the laparoscopic and open groups with regard to estimated blood loss (31 versus 40 ml, respectively) or mean length of stay (5.3 vs. 5.7 days, respectively). The rates of overall 30-day morbidity (16.9 % for laparoscopic vs. 21.3 % for open) as well as rates of specific complications were equivalent between groups. 30-day mortalities were not noted in either group. Conclusion: LIR is safe and effective with low perioperative morbidity and mortality. The use of laparoscopy as an option in terms of concomitant hernia repair and lysis of adhesions may be considered in selected patients.

Purpose: To evaluate mutations in the visual system homeobox gene 1 (VSX1) and superoxide dismutase 1 (SOD1) genes with keratoconus (KTCN), direct sequencing was performed in an Iranian population. Methods: One hundred and twelve autosomal dominant KTCN patients and fifty-two unaffected individuals from twentysix Iranian families, as well as one hundred healthy people as controls were enrolled. Genomic DNA was extracted from whole blood sample. Then to study the possible linkage between KTCN and six known loci linkage analysis was performed using 12 short tandem repeat (STR) markers. Also, the entire coding region and intron-exon boundaries of VSX1 and SOD1 were amplified by the PCR technique in each proband. Subsequently, PCR products were subjected to direct sequencing. Co-segregation analysis of the identified mutation was conducted in the family members. An Amplification Refractory Mutation System PCR (ARMS-PCR) was additionally employed for detection of the identified mutation in healthy controls. Results: Linkage analysis of aforementioned loci did not detect evidence for linkage to KTCN. Direct PCR sequencing revealed two single nucleotide polymorphisms (SNPs; g.1502T>G and g.9683C>T), as well as two missense mutations that have been previously reported (R166W and H244R) in VSX1. We also found three undescribed SNPs (g.4886G>A, g.4990C>G, and g.9061T>A) in SOD1. The R166W and H244R mutations were co-segregated in affected family members but not in those that were unaffected. Moreover, the ARMS-PCR strategy did not detect the identified mutations in controls. Conclusions: Our data suggest a significant association between KTCN patients and VSX1 genetic alterations (p.R166W and p.H244R). Although our findings support VSX1 as a plausible candidate gene responsible for keratoconus, other chromosomal loci and genes could be involved in KTCN development. Taken together, our results suggest that p.R166W and p.H244R could have possible pathogenic influences on KTCN.

Purpose: To evaluate mutations in the visual system homeobox gene 1 (VSX1) and superoxide dismutase 1 (SOD1) genes with keratoconus (KTCN), direct sequencing was performed in an Iranian population. Methods: One hundred and twelve autosomal dominant KTCN patients and fifty-two unaffected individuals from twentysix Iranian families, as well as one hundred healthy people as controls were enrolled. Genomic DNA was extracted from whole blood sample. Then to study the possible linkage between KTCN and six known loci linkage analysis was performed using 12 short tandem repeat (STR) markers. Also, the entire coding region and intron-exon boundaries of VSX1 and SOD1 were amplified by the PCR technique in each proband. Subsequently, PCR products were subjected to direct sequencing. Co-segregation analysis of the identified mutation was conducted in the family members. An Amplification Refractory Mutation System PCR (ARMS-PCR) was additionally employed for detection of the identified mutation in healthy controls. Results: Linkage analysis of aforementioned loci did not detect evidence for linkage to KTCN. Direct PCR sequencing revealed two single nucleotide polymorphisms (SNPs; g.1502T>G and g.9683C>T), as well as two missense mutations that have been previously reported (R166W and H244R) in VSX1. We also found three undescribed SNPs (g.4886G>A, g.4990C>G, and g.9061T>A) in SOD1. The R166W and H244R mutations were co-segregated in affected family members but not in those that were unaffected. Moreover, the ARMS-PCR strategy did not detect the identified mutations in controls. Conclusions: Our data suggest a significant association between KTCN patients and VSX1 genetic alterations (p.R166W and p.H244R). Although our findings support VSX1 as a plausible candidate gene responsible for keratoconus, other chromosomal loci and genes could be involved in KTCN development. Taken together, our results suggest that p.R166W and p.H244R could have possible pathogenic influences on KTCN.

It is well known from the seminal Brockett's theorem that the openness property of the mapping on the right-hand side of a given nonlinear ODE control system is a necessary condition for the existence of locally asymptotically stabilizing continuous stationary feedback laws. However, this condition fails to be sufficient for such a feedback stabilization. In this paper we develop an approach of variational analysis to continuous feedback stabilization of nonlinear control systems with replacing openness by the linear openness property, which has been well understood and characterized in variational theory. It allows us, in particular, to obtain efficient conditions via the system data supporting the sufficiency in Brockett's theorem and ensuring local exponential stabilization by means of continuous stationary feedback laws. Furthermore, we derive new necessary conditions for local exponential and asymptotic stabilization of continuous-time control systems by using both continuous and continuously differentiable stationary feedback laws and establish also some counterparts of the obtained sufficient conditions for local asymptotic stabilization by continuous stationary feedback laws in the case of nonlinear discrete-time control systems. © 2018 American Institute of Mathematical Sciences. All rights reserved.