An electrophoretic study of representatives of subgenus Diploxylon of Pinus

1989 ◽  
Vol 67 (6) ◽  
pp. 1750-1759 ◽  
Author(s):  
Roopa R. Karalamangala ◽  
Daniel L. Nickrent

Relationships among 14 taxa in subgenus Diploxylon of Pinus from Mexico and the United States were analyzed using 15 isozyme loci obtained from both frozen and fresh needle tissue. The phenogram obtained from cluster analysis of genetic distance values and phylogenetic trees implementing the distance Wagner procedure were in general agreement with classifications based on morphological features. Pinus leiophylla is genetically distinct from other species. Two groupings, one comprising P. oocarpa and P. pringlei and another comprising P. lawsonii and P. teocote, correspond to sections Serotinus and Teocote (sensu Martínez), respectively. Classification of the remaining eight taxa has varied, ranging from their placement in three, two, or only one section. Isozyme analysis resulted in a group that included P. cooperi, P. douglasiana, P. durangensis, P. michoacana, and P. montezumae, which suggests genetic affinity between Sections Pseudostrobus and Montezumae (sensu Martínez). This result corresponds more closely to the placement of these species in subsection Pseudostrobi. The distant relationship between P. engelmannii and the ponderosa pines may be anomalous (an artifact of small sample size) or may indicate greater genetic divergence than previously recognized.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e17502-e17502
Author(s):  
Anahat Kaur ◽  
Shuai Wang ◽  
Tarek N. Elrafei ◽  
Lewis Steinberg ◽  
Abhishek Kumar

e17502 Background: Glassy cell carcinoma of cervix (GCCC) is a rare histological subtype of cervical cancer which has historically been associated with rapidly progressive disease, early development of metastases and overall poor prognosis. We attempt to define real-world trends in GCCC in the United States based on data from SEER (Surveillance, Epidemiology and End Results) database. Methods: We extracted data from the US National Cancer Institute's SEER 2018 dataset using ICD-O code for ‘Cervix Uteri Glassy Cell Carcinoma’. All patients who were diagnosed between 1973-2015 were included. Statistical analysis was done using SPSS 26. Kaplan Meier curve was used for survival analysis. Results: Data for a total of 57 patients with GCCC was available from 1975 to 2017. Median age at diagnosis was 38 years (range 30.5-44.5). Increased frequency of cases was noted in white females (77.2%) as compared to black population (22.2%). Most cases initially presented with localized or regional spread (47.4% and 40.4% respectively) with distant metastasis seen in only 10.5% patients. Data analysis revealed that 63.2% patients had Grade III poorly differentiated carcinoma, 66.7% received radiation therapy, 57.9% underwent chemotherapy and 59.6% had cancer direceted surgery performed. Calculated mean overall survival was 121.9 months. We were unable to calculate 5 year and 10 year median overall survival due to small sample size and censored data. Conclusions: GCCC is a rare histologic type of cervical cancer that presents at a younger age, is more frequently seen in white females and is commonly associated with localized or regional spread at time of initial presentation.[Table: see text]


2021 ◽  
Vol 12 ◽  
Author(s):  
Joshua Ong ◽  
Andrew G. Lee ◽  
Heather E. Moss

Astronauts who undergo prolonged periods of spaceflight may develop a unique constellation of neuro-ocular findings termed Spaceflight Associated Neuro-Ocular Syndrome (SANS). SANS is a disorder that is unique to spaceflight and has no terrestrial equivalent. The prevalence of SANS increases with increasing spaceflight duration and although there have been residual, structural, ocular changes noted, no irreversible or permanent visual loss has occurred after SANS, with the longest spaceflight to date being 14 months. These microgravity-induced findings are being actively investigated by the United States' National Aeronautics Space Administration (NASA) and SANS is a potential obstacle to future longer duration, manned, deep space flight missions. The pathophysiology of SANS remains incompletely understood but continues to be a subject of intense study by NASA and others. The study of SANS is of course partially limited by the small sample size of humans undergoing spaceflight. Therefore, identifying a terrestrial experimental model of SANS is imperative to facilitate its study and for testing of preventative measures and treatments. Head-down tilt bed rest (HDTBR) on Earth has emerged as one promising possibility. In this paper, we review the HDTBR as an analog for SANS pathogenesis; the clinical and imaging overlap between SANS and HDTBR studies; and potential SANS countermeasures that have been or could be tested with HDTBR.


Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Navdeep S Sangha ◽  
Duy Le ◽  
Raeesa Dhanji ◽  
Denise Gaffney ◽  
David McCartney ◽  
...  

Background: IV tPA is established as an effective treatment for acute ischemic stroke. Currently it is endorsed up to 4.5 hours of last known well time by major guidelines. A randomized trial, WAKE-UP, displayed its safety and efficacy in patients who presented within 4.5 hours of waking up with their symptoms. Objective: To establish a practical tPA protocol for patients who wake up or are found with stroke symptoms at a large Comprehensive Stroke Center (CSC) and its 13 telestroke spokes (TS) based on the WAKE-UP trial. Methods: A wake up tPA protocol was created and given to all teleneurologists. Door to needle times (DTN) and reasons for no tPA were collected for 12 months post implementation and evaluated for differences between wake up (WU) and non-wake up (NW) patients. Results: 93 WU patients were identified; 23 at CSC and 70 at TS. 11 (47.8%) vs. 4 (5.7%) patients received tPA at CSC and TS, respectively. Median DTN was not significantly different for WU patients at CSC vs. TS (64 vs. 89 mins, p=0.54). Median DTN at CSC was shorter for NW vs. WU (37 vs. 64 mins; p=0.003). Similarly, median DTN at TS trended toward being shorter for NW vs. WU (44 vs. 89 mins; p=0.062). The reasons for no tPA at CSC were no mismatch found in 6 (50%), and MRI unavailability in 6 (50%); at TS were no mismatch found in 11 (16.6%), MRI unavailability in 54 (81,1%) and MRI was contraindicated in 1 (1.5%). Conclusion: Treating WU patients using a CSC Hub and TS model is feasible. DTN are longer for WU vs. NW. In the United States, MRI availability is the main barrier to WU tPA at both CSC and community hospitals. The difference between median DTN for WU between CSC and TS did not reach statistical significance, likely due to the small sample size.


2020 ◽  
Author(s):  
michael e johansen

Introduction: I attempted to determine rates of use and associations with use of acid-suppressing medications in infants under 2 years old given these are not well studied. Methods: The 2002-2018 Medical Expenditure Panel Survey (MEPS) was used for the analysis. The survey is sponsored by the Agency of Healthcare Research and Quality and is conducted on households to be nationally representative of the non-institutionalized population of the United States. The survey is comprised of two overlapping panels that are each included in the survey for two years. Newborns and infants under 2 years old on December 31 of a survey year were included in the study. Additionally, adult men and women living in the same household between 18-45 years old were considered fathers and mothers of infants. Histamine2-receptor antagonists (H2RA) and proton pump inhibitors (PPI) were identified for infants. H2RA, PPIs, and anti-depressant (selective serotonin re-uptake inhibitors and serotonin-norepinephrine re-uptake inhibitors) were identified for parents. Sex, age (by month for child), race/ethnicity (White non-Hispanic, Black non-Hispanic, Hispanic, or other), region (Northeast, Midwest, South, and West), and poverty category were identified. Chi-squared and adjusted Wald tests were used to determine statistical significance with acid-suppressing medication use between 2010-2018. A multivariable logistic regression predicted any acid suppressing medication use with month of age and month of age2 as independent variables of use for the population between 2009-2018. The study was considered exempt by the OhioHealth Institutional Review Board. Survey weighting was included in all analyses. Results: The study included a total of 16,604 infants between 2002-2018. The rate of any acid suppressing medication increased between 2002-2004. H2RA use was more common than PPI use, especially after 2012. H2RA use appeared to increase after 2015. PPI use initially increased, but then remained relatively stable before appearing to decrease in 2015-2018. Ranitidine clearly had the most users of the H2RA, which was maintained throughout the study period. Lansoprazole had the most users among users of PPIs, but this decreased notably after 2010. Of the infants with a reported PPI, 34.0% (95%CI:23.6-46.3) also had an H2RA reported during the year. In total, 40.8% (95%CI:35.0-46.8) had only 1 reported fill of an acid suppresser. There were 8,075 infants under 2 years of age between 2010-2018. The rate of use was highest in infants between 4-11 months of age at the end of the survey year at 8.6% (95%CI:6.9-10.6). Acid-suppressing medication use was more common among infants in higher income families, White (non-Hispanic) race/ethnicity, infants with private health insurance, parents who reported acid-suppressing medication, maternal anti-depressant use, and certain regions of the country. Discussion: Between 6.9-10.6% of infants used an acid suppressing medication before their second birthday between 2010-2018, of which around 60% had multiple medication fills. It appears that there has been a small increases in use over the last few decades, of which ranitidine appears to be the medication driving the increase. Numerous socio-economic and demographic characteristics were associated with acid suppressing medication use. This study has numerous limitations, including potential under-reporting of acid-suppressing medications, an imperfect identification of parent, unreliable diagnoses (not included in the analysis), and a relatively small sample size. We opted not to run a multivariable logistic regression of socio-economic and demographic characteristics given concern for table 2 fallacy and relatively small sample size. Acid suppressing medication use was common in infants before their second birthday. Additional research should be conducted on efficacy and safety of these medications given the level of use and very low quality of available evidence.


Author(s):  
Susan Kemper Patrick ◽  
Francisco Arturo Santelli

Educational leaders throughout the United States have repeatedly emphasized the importance of increasing the number of Black and Latinx teachers in American schools. Prior qualitative work suggests that Black and Latinx teachers who are demographically isolated in their schools often report negative experiences. Drawing on theories of proportional representation in organizations, we use Tennessee statewide survey and administrative data to examine whether self-reported professional experiences of Black and Latinx teachers are different when they are demographically isolated. We estimate models using two measures of demographic isolation: a continuous measure and a theoretically generated ordinal measure. We find that, for Black teachers, the percentage of Black teachers in the school is positively associated with teachers’ perceived satisfaction and support and with the frequency of collaboration. There is also some evidence of threshold effects of demographic isolation for Black teachers, as Black teachers in schools in which at least 60% of fellow teachers are Black report significantly higher satisfaction and support than other Black teachers. Our models do not find any associations between isolation and professional experience for Latinx teachers, but a small sample size and lack of variation in demographic isolation among Latinx teachers makes it difficult to estimate these associations. Our findings suggest that both ordinal and continuous measures of demographic isolation may be useful when examining relationships between demographic isolation and workplace experiences. Because we study factors linked to turnover in prior research, these analyses can contribute to the broader discussion about the retention of Black and Latinx teachers.


Author(s):  
Lewis M. Cowardin ◽  
Virginia Carter ◽  
Francis C. Golet ◽  
Edward T. Laroe

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