Risk factors and outcomes of peptic ulcer bleed in a Pakistani population: A single-center observational study

BACKGROUND

Peptic ulcer disease (PUD) remains a significant healthcare burden, contributing to morbidity and mortality worldwide. Despite advancements in therapies, its prevalence persists, particularly in regions with widespread nonsteroidal anti-inflammatory drugs (NSAIDs) use and Helicobacter pylori infection.

AIM

To comprehensively analyse the risk factors and outcomes of PUD-related upper gastrointestinal (GI) bleeding in Pakistani population.

METHODS

This retrospective cohort study included 142 patients with peptic ulcer bleeding who underwent upper GI endoscopy from January to December 2022. Data on demographics, symptoms, length of stay, mortality, re-bleed, and Forrest classification was collected.

RESULTS

The mean age of patients was 53 years, and the majority was men (68.3%). Hematemesis (82.4%) and epigastric pain (75.4%) were the most common presenting symptoms. Most patients (73.2%) were discharged within five days. The mortality rates at one week and one month were 10.6% and 14.8%, respectively. Re-bleed within 24 h and seven days occurred in 14.1% and 18.3% of patients, respectively. Most ulcers were Forrest class (FC) III (72.5%). Antiplatelet use was associated with higher mortality at 7 and 30 d, while alternative medications were linked to higher 24-hour re-bleed rates. NSAID use was associated with more FC III ulcers. Re-bleed at 24 h and 7 d was strongly associated with one-week or one-month mortality.

CONCLUSION

Antiplatelet use and rebleeding increase the risk of early mortality in PUD-related upper GI bleeding, while alternative medicines are associated with early rebleeding.

First-Principles Investigation of Novel Alkali-Based Lead-Free Halide Perovskites for Advanced Optoelectronic Applications

Lead-free halide perovskites are considered promising candidates as visible light absorbers with outstanding optoelectronic properties. In this work, novel kinds of lead-free halide perovskites were studied for their electronic, optical, and thermoelectric properties by employing the most precise and enhanced modified Trans-Blaha Beck-Johnson potential. The estimated band spectra of the studied materials were comparable. The materials are confirmed to have an indirect band gap semiconducting nature due to the existence of energy band gaps. Among the studied materials, CsSnI3 has a smaller band gap, confirming the excitation to be more energy efficient. Examining the predicted density of states and true electronic orbital contributions, we observed a progressive fluctuation along the energy axis was observed. Furthermore, the linear optical properties are calculated and studied in terms of possible optoelectronic applications. The absorption in KSnI3 was greater compared to the other two materials. The studied materials could be used for antireflecting coatings against UV radiation, owing to the prominent peaks in their reflectivity spectra. The Seebeck coefficient and electrical properties, as well as the positive value of RH all pointed to a p-type nature in these materials. From the anticipated thermoelectric properties, the materials also appear to be suitable for application in thermoelectric devices.

Revisiting phylogeny, systematics, and biogeography of a Pleistocene radiation

PREMISE

Pilosocereus (Cactaceae) is an important dry forest element in all subregions and transitional zones of the neotropics, with the highest diversity in eastern Brazil. The genus is subdivided into informal taxonomic groups; however, most of these are not supported by recent molecular phylogenetic inferences. This lack of confidence is probably due to the use of an insufficient number of loci and the complexity of cactus diversification. Here, we explored the species relationships in Pilosocereus in more detail, integrating multilocus phylogenetic approaches with the assessment of the ancestral range and the effect of geography on diversification shifts.

METHODS

We used 28 nuclear, plastid, and mitochondrial loci from 54 plant samples of 31 Pilosocereus species for phylogenetic analyses. We used concatenated and coalescent phylogenetic trees and Bayesian models to estimate the most likely ancestral range and diversification shifts.

RESULTS

All Pilosocereus species were clustered in the same branch, except P. bohlei. The phylogenetic relationships were more associated with the geographic distribution than taxonomic affinities among taxa. The genus began diversifying during the Plio-Pleistocene transition in the Caatinga domain and experienced an increased diversification rate during the Calabrian age.

CONCLUSIONS

We recovered a well-supported multispecies coalescent phylogeny. Our results refine the pattern of rapid diversification of Pilosocereus species across neotropical drylands during the Pleistocene and highlight the need for taxonomic rearrangements in the genus. We recovered a pulse of diversification during the Pleistocene that was likely driven by multiple dispersal and vicariance events within and among the Caatinga, Cerrado, and Atlantic Forest domains.

Investigation of Structural, Mechanical, Optoelectronic, and Thermoelectric Properties of BaXF3 (X = Co, Ir) Fluoro-Perovskites: Promising Materials for Optoelectronic and Thermoelectric Applications

Coded within Wien2K, we carry out DFT-based calculations for investigations of the structural, elastic, optoelectronic, and thermoelectric properties of BaXF₃ (X = Co, Ir) fluoro-perovskites. The Birch-Murnaghan fit to the energy-vs-volume data and formation energy shows that these fluoro-perovskites are structurally stable. The phonon calculation confirms the thermodynamic stability, while the relation between elastic constants such as C ₁₁ - C ₁₂ > 0, C ₁₁ > 0, C ₁₁ + 2C ₁₂ > 0, and B > 0 validates the mechanical stability of the compounds. BaIrF₃ exhibits a strong ability to endure compressive and shear stresses. BaCoF₃ shows a weaker capacity of withstanding changes in volume, attributed to a lower bulk modulus. Demonstrating a higher G-modulus of rigidity than the BaIrF₃, BaCoF₃ demonstrates stronger resistance to change the shape and both compounds are found to be anisotropic and brittle. The determined band structure profiles reveal that both BaCoF₃ and BaIrF₃ demonstrate a metallic nature. In addition, the metallic nature of BaCoF₃ and BaIrF₃ is reinforced by the density-of-states (DOS) study, where Co and F atoms contribute significantly to the total DOS in the valence band in the case of BaCoF₃, while that of BaIrF₃ is predominated by the Ba and F atoms. The computed values of ε₁(0) for BaCoF₃ and BaIrF₃ are approximately 30 and 19, respectively, which are in line with Penn's model. The researched materials are confirmed to be strong contenders for optoelectronics by the lack of absorption in the visible range. For their potential use in thermoelectric device applications, thermoelectric parameters such as temperature-dependent Seebeck coefficient, specific heat capacity, thermal conductivity, power factor, and figure of merit are also investigated, which show that these materials are thermally stable and promising for applications in thermoelectric devices.

Computational evaluation of novel barium zinc chalcogenides Ba2ZnCh3 (Ch = S, Se, Te) for advanced optoelectronic applications

Due to their outstanding optoelectronic characteristics, ternary chalcogenides are considered an attractive choice for absorbers of visible light. Here, a novel family of ternary chalcogenides, Ba₂ZnCh₃ (Ch = S, Se, Te), is examined in the context of density functional theory calculations. The atomic locations in these materials are determined before the bulk modulus, cohesive energy, and lattice constant predictions. Our examined materials are semiconductors by nature, as indicated by the electronic band profiles with both the WC-GGA potential and TB-mBJ potential revealing an energy gap between the valence and conduction bands. Using full geometrical optimization and the force minimization technique based on Broyden's scheme, the interior atomic positions and the relaxed structures were obtained. The formation energies are likely more consistent with a convex hull near the configuration of interest. The cohesive energies confirmed that Ba₂ZnS₃ has the most cohesive nature as compared to the other two materials. Likewise, the calculated components of the dielectric function of the individual materials were anisotropic having dissimilar values along different dimensions. The computed sharp peaks of the absorption coefficient for Ba₂ZnS₃, Ba₂ZnSe₃, and Ba₂ZnTe₃ confirm their improved absorption behavior in the UV range. Moreover, the thermoelectric characteristics were computed, and the findings are detailed, indicating that all of these materials are efficient for thermoelectric device applications.

First-principles structural, elastic and optoelectronics study of sodium niobate and tantalate perovskites

The intensified quest for efficient materials drives us to study the alkali (Na)-based niobate (NaNbO₃) and tantalate (NaTaO₃) perovskites while exploiting the first-principles approach based on density functional theory, coded within WIEN2K. While using the Birch Murnaghan fit, we find these materials to be stable structurally. Similarly, the ab-initio molecular dynamics simulations (AIMD) at room temperature reveals that the compounds exhibit no structural distortion and are stable at room temperature. By using the recommended modified Becke-Johnson potential, we determine the electronic characteristics of the present materials providing insight into their nature: they are revealed to be indirect semiconductors with the calculated bandgaps of 2.5 and 3.8 eV for NaNbO₃ and NaTaO₃, respectively. We also determine the total and partial density of states for both materials and the results obtained for the bandgap energies of these materials are consistent with those determined by the band structure. We find that both compounds exhibit transparency to the striking photon at low energy and demonstrate absorption and optical conduction in the UV region. The elastic study shows that these compounds are mechanically stable, whereas NaNbO₃ exhibits stronger ability to withstand compressive as well as shear stresses and resists change in shape while NaTaO₃ demonstrates weaker ability to resist change in volume. We also find that none of the compound is perfectly isotropic and NaNbO₃ and NaTaO₃ are ductile and brittle in nature, respectively. By studying the optical properties of these materials, we infer that they are promising candidates for applications in optoelectronic devices. We believe that this report will invoke the experimental studies for further investigation.

Comparative simulations study of radiations shielding properties of 69P2O5–10Gd2O3/10GdF3–10BaO–10ZnO–1Er2O3 glasses

We study the theoretical and simulated shielding properties of 69P2O5–10Gd2O3–10BaO–10ZnO–1Er2O3 and 69P2O5–10GdF3–10BaO–10ZnO-1Er2O3 glasses. We exploit advanced simulation (MCNPX) and Phy-X, an online Photon Shielding and Dosimetry software, in the 0.001–15 MeV energy range, to calculate the linear attenuation coefficient and mass attenuation coefficients of the samples. The obtained mass attenuation coefficient is then used to calculate the critical radiation shielding characteristics, such as the half-value layer, mean free path, tenth value layer, and effective atomic number. The calculated LAC values range from 108.759 to 0.097 and from 84.124 to 0.087 cm−1 while HVL values range from 0.006 to 7.164 and from 0.008 to 8.013 cm, and MFP values vary from 0.009 to 10.335 and from 0.012 to 11.561 cm for ZBaOEr and ZBaFEr, respectively, with energy ranging from 0.015 to 15 MeV. We find that the results obtained from MCNPX and Phy-X are consistent with each other, based on the computed relative difference. The glass sample containing Gd2O3 exhibits better shielding properties than the one with GdF3, over the entire energy range. Our examined glass samples are thick enough to substantially lessen the intensity of incident X-rays and gamma rays.

Development and Testing of the A1 Volumetric Air Sampler, an Automatic Pollen Trap Suitable for Long-Term Monitoring of eDNA Pollen Diversity

Airborne pollen surveys provide information on various aspects of biodiversity and human health monitoring. Such surveys are typically conducted using the Burkard Multi-Vial Cyclone Sampler, but have to be technically optimized for eDNA barcoding. We here developed and tested a new airborne pollen trap, especially suitable for autonomous eDNA-metabarcoding analyses, called the A1 volumetric air sampler. The trap can sample pollen in 24 different tubes with flexible intervals, allowing it to operate independently in the field for a certain amount of time. We compared the efficiency of the new A1 volumetric air sampler with another automated volumetric spore trap, the Burkard Multi-Vial Cyclone Sampler, which features shorter and fewer sampling intervals to evaluate the comparability of ambient pollen concentrations. In a sterile laboratory environment, we compared trap performances between the automated volumetric air samplers by using pure dry pollen of three species-Fagus sylvatica, Helianthus annuus and Zea mays-which differ both by exine ornamentation and pollen size. The traps had a standard suction flow rate of 16.5 L/min, and we counted the inhaled pollen microscopically after a predefined time interval. Our results showed that though we put three different pollen types in the same container, both the traps inhaled all the pollens in a statistically significant manner irrespective of their size. We found that, on average, both traps inhaled equal an number of pollens for each species. We did not detect any cross-contamination between tubes. We concluded that the A1 volumetric air sampler has the potential to be used for longer and more flexible sampling intervals in the wild, suitable for autonomous monitoring of eDNA pollen diversity.

Reassessment of the Phylogeny and Systematics of Chinese Parnassia (Celastraceae): A Thorough Investigation Using Whole Plastomes and Nuclear Ribosomal DNA

Parnassia L., a perennial herbaceous genus in the family Celastraceae, consists of about 60 species and is mainly distributed in the Pan-Himalayan and surrounding mountainous regions. The taxonomic position and phylogenetic relationships of the genus are still controversial. Herein, we reassessed the taxonomic status of Parnassia and its intra- and inter-generic phylogeny within Celastraceae. To that end, we sequenced and assembled the whole plastid genomes and nuclear ribosomal DNA (nrDNA) of 48 species (74 individuals), including 25 species of Parnassia and 23 species from other genera of Celastraceae. We integrated high throughput sequence data with advanced statistical toolkits and performed the analyses. Our results supported the Angiosperm Phylogeny Group IV (APG IV) taxonomy which kept the genus to the family Celastraceae. Although there were topological conflicts between plastid and nrDNA phylogenetic trees, Parnassia was fully supported as a monophyletic group in all cases. We presented a first attempt to estimate the divergence of Parnassia, and molecular clock analysis indicated that the diversification occurred during the Eocene. The molecular phylogenetic results confirmed numerous taxonomic revisions, revealing that the morphological characters used in Parnassia taxonomy and systematics might have evolved multiple times. In addition, we speculated that hybridization/introgression might exist during genus evolution, which needs to be further studied. Similarly, more in-depth studies will clarify the diversification of characters and species evolution models of this genus.

Dispersal into the Qinghai-Tibet plateau: evidence from the genetic structure and demography of the alpine plant Triosteum pinnatifidum

Triosteum pinnatifidum Maxim., an alpine plant, is traditionally used for several medicinal purposes. Here, both chloroplast DNA sequences and nuclear low copy sequence markers were used to investigate the genetic diversity and population structure of T. pinnatifidum. Materials were collected from thirteen localities in the northeast Qinghai-Tibet Plateau (QTP) and adjacent highlands and advanced analytical toolkits were used to access their origin and range shifts. The results revealed a higher level of population differentiation based on chloroplast DNA (cpDNA) concatenated sequences compared with the nuclear DNA sequences (F _ST = 0.654 for cpDNA, F _ST = 0.398 for AT103), indicating that pollen flow was still extensive in T. pinnatifidum. A decline in haplotype variation was observed from the plateau edge and adjoining highlands toward the platform of the QTP. The hypothesis "dispersal into the QTP," proposing that T. pinnatifidum experienced migration from the plateau edge and adjacent highlands to the platform, was supported. These results were in line with the hypothesis that multiple refugia exist on the plateau edge and adjacent highlands rather than on the plateau platform. Our unimodal mismatch distribution, star-like network supported a recent expansion in T. pinnatifidum.

Plastome sequencing reveals phylogenetic relationships among Comastoma and related taxa (Gentianaceae) from the Qinghai-Tibetan Plateau

Genus Comastoma (subt. Swertiinae, Gentianaceae) contains species, such as "Zangyinchen," that are important herbs in Tibetan medicine. The phylogenetic relationship of this within Gentianaceae and the circumscriptions of its species have long been controversial with conflicting morphological and molecular data reported. Here, we used whole chloroplast genome sequences for Comastoma species and related taxa to reconstruct their phylogeny and clarify their taxonomic relationships. The results revealed that the length of all plastome sequenced varied from 149 to 151 kb and have high similarity in structure and gene content. Phylogenomic analysis showed that Comastoma is a monophyletic group, closely related to the genus Lomatogonium. The divergence time estimation showed that Gentianaceae diverged at about 21.81 Ma, while the split of Comastoma occurred at 7.70 Ma. However, the results suggested the crown age of species formation in this genus is after 4.19 Ma. Our results suggest that QTP uplift, the alternation of Quaternary glaciation and interglaciation, and monsoon changes might have acted as drivers of speciation in Comastoma.

Incongruent phylogenies and their implications for the study of diversification, taxonomy, and genome size evolution of Rhododendron

PREMISE

Classification of taxa depends on the quality of inferred phylogenies. Rhododendron, a highly species-rich genus (>1156 species) of woody plants, has a highly debated infrageneric classification, due to its huge diversity, homoplasy in key characters, and incongruence among data sets. We provide a broad coverage of representative species to resolve Rhododendron infrageneric phylogeny and highlight the areas of incongruence. We further investigate the effect of polyploidy and genome size evolution on diversification of Rhododendron.

METHODS

We generated two plastid and two nuclear loci for 260 Rhododendron species. We analyzed the loci separately as well as concatenated, utilizing both likelihood and Bayesian methods. We tested incongruence both among the data sets and with previous studies. We estimated genome sizes for 125 species through flow cytometry.

RESULTS

Our results suggest stronger support for larger subgenera; however, the smaller subgenera pose several problems; for example, R. tomentosum (former genus Ledum) occupies incongruent positions based on different DNA regions. The main shift to higher diversification in the genus occurs in the Himalayan/Southeast Asian clade of R. subg. Hymenanthes. We found that polyploidy occurs in almost all subgenera but most frequently within R. subg. Rhododendron sections Rhododendron and Schistanthe.

CONCLUSIONS

We endorse the recognition of five major clades at the subgeneric level, but a number of species cannot be confidently assigned to these clades due to incongruency. With regard to genome size evolution, results support previous reports that genome sizes of tropical plants are lower than those of colder and temperate regions and that genome downsizing promotes diversification.

Comparative Phylogeography of Veronica spicata and V. longifolia (Plantaginaceae) Across Europe: Integrating Hybridization and Polyploidy in Phylogeography

Climatic fluctuations in the Pleistocene caused glacial expansion-contraction cycles in Eurasia and other parts of the world. Consequences of these cycles, such as population expansion and subsequent subdivision, have been studied in many taxa at intraspecific population level across much of the Northern Hemisphere. However, the consequences for the potential of hybridization and polyploidization are poorly understood. Here, we investigated the phylogeographic structure of two widespread, closely related species, Veronica spicata and Veronica longifolia, across their European distribution ranges. We assessed the extent and the geographic pattern of polyploidization in both species and hybridization between them. We used genome-scale SNP data to clarify phylogenetic relationships and detect possible hybridization/introgression events. In addition, crossing experiments were performed in different combination between V. spicata and V. longifolia individuals of two ploidy levels and of different geographic origins. Finally, we employed ecological niche modeling to infer macroclimatic differences between both species and both ploidy levels. We found a clear genetic structure reflecting the geographical distribution patterns in both species, with V. spicata showing higher genetic differentiation than V. longifolia. We retrieved significant signals of hybridization and introgression in natural populations from the genetic data and corroborated this with crossing experiments. However, there were no clear phylogeographic patterns and unequivocal macroclimatic niche differences between diploid and tetraploid lineages. This favors the hypothesis, that autopolyploidization has happened frequently and in different regions. The crossing experiments produced viable hybrids when the crosses were made between plants of the same ploidy levels but not in the interploidy crosses. The results suggest that hybridization occurs across the overlapping areas of natural distribution ranges of both species, with apparently directional introgression from V. spicata to V. longifolia. Nevertheless, the two species maintain their species-level separation due to their adaptation to different habitats and spatial isolation rather than reproductive isolation.

Clinical and Radiological Study of Serum Fluoride in Relation to Knee Osteoarthritis

Introduction

Fluorosis has been associated with an increased risk of degenerative changes in the knee. Multiple studies have found an association between arthritis and elevated fluoride levels. We aim to delineate if elevated fluoride level has any direct correlation with the degree of radiological grading and clinical symptoms in knee arthritis.

Materials and Methods

A cross-sectional study of 80 knee arthritis patients was conducted from February 2017 to April 2018. Serum fluoride levels were measured and patient's pain scores, WOMAC scores and radiological grading were correlated with the elevated fluoride levels.

Results

In our study, 30 out of 80 patients had increased serum fluoride level. Statistically significant differences were noted in VAS score, WOMAC score and Kellgren and Lawrence radiological grades between patients with normal serum fluoride level and those with elevated fluoride level.

Conclusion

There is an increased risk of knee arthritis in patients with elevated blood fluoride levels and patients with increased fluoride levels are associated with more severe symptoms and radiographic disease.

Enhanced photocatalytic activity of Ag-coated ZnO nanorods for the degradation of methylene blue

Worldwide water pollution is a serious issue, which needs special attention. Among these pollutants, methylene blue (MB) is dangerous for aquatic life as well as for human beings. Researchers are trying their best to degrade the various pollutants found in water. In the present work, we synthesized ZnO nanorods (NRDs) by one-step hydrothermal method. The synthesized samples were then characterized with the help of X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). ZnO nanostructures were composed of rod-shaped NRDs with flat edges and were highly crystalline with hexagonal shaped morphology. UV/Visible spectroscopy was carried out to investigate the optical properties, which shows the absorption in UV range and highly transmittance in the visible range. Finally, the photocatalytic activity was performed for the degradation of MB. The results show that MB was not fully degraded by bare ZnO NRDs. After all, we coated Ag NPs on the surfaces of ZnO NRDs through the simple solution-based method. The UV/Visible data reveal absorption in the UV as well as in the visible range due to the surface plasmonic effect of Ag NPs. Hybrid Ag-coated ZnO NRDs successfully degraded MB within 60 min. Therefore, we found that Ag-coated ZnO NRDs show good photocatalytic properties as compared to uncoated ZnO NRDs.

Population subdivision and hybridization in a species complex of Gentiana in the Qinghai-Tibetan Plateau

BACKGROUND AND AIMS

Hosting several global biodiversity hotspots, the region of the Qinghai-Tibetan Plateau (QTP) is exceptionally species-rich and harbours a remarkable level of endemism. Yet, despite a growing number of studies, factors fostering divergence, speciation and ultimately diversity remain poorly understood for QTP alpine plants. This is particularly the case for the role of hybridization. Here, we explored the evolutionary history of three closely related Gentiana endemic species, and tested whether our results supported the mountain geo-biodiversity hypothesis (MGH).

METHODS

We genotyped 69 populations across the QTP with one chloroplast marker and 12 nuclear microsatellite loci. We performed phylogeographical analysis, Bayesian clustering, approximate Bayesian computation and principal components analysis to explore their genetic relationship and evolutionary history. In addition, we modelled their distribution under different climates.

KEY RESULTS

Each species was composed of two geographically distinct clades, corresponding to the south-eastern and north-western parts of their distribution. Thus Gentiana veitchiorum and G. lawrencei var. farreri, which diverged recently, appear to have shared at least refugia in the past, from which their range expanded later on. Indeed, climatic niche modelling showed that both species went through continuous expansion from the Last Interglacial Maximum to the present day. Moreover, we have evidence of hybridization in the northwest clade of G. lawrencei var. farreri, which probably occurred in the refugium located on the plateau platform. Furthermore, phylogenetic and population genetic analyses suggested that G. dolichocalyx should be a geographically limited distinct species with low genetic differentiation from G. lawrencei var. farreri.

CONCLUSIONS

Climatic fluctuations in the region of the QTP have played an important role in shaping the current genetic structure of G. lawrencei var. farreri and G. veitchiorum. We argue that a species pump effect did occur prior to the Last Interglacial Maximum, thus lending support to the MGH. However, our results do depart from expectations as suggested in the MGH for more recent distribution range and hybridization dynamics.

Expanded inverted repeat region with large scale inversion in the first complete plastid genome sequence of Plantago ovata

Plantago ovata (Plantaginaceae) is an economically and medicinally important species, however, least is known about its genomics and evolution. Here, we report the first complete plastome genome of P. ovata and comparison with previously published genomes of related species from Plantaginaceae. The results revealed that P. ovata plastome size was 162,116 bp and that it had typical quadripartite structure containing a large single copy region of 82,084 bp and small single copy region of 5,272 bp. The genome has a markedly higher inverted repeat (IR) size of 37.4 kb, suggesting large-scale inversion of 13.8 kb within the expanded IR regions. In addition, the P. ovata plastome contains 149 different genes, including 43 tRNA, 8 rRNA, and 98 protein-coding genes. The analysis revealed 139 microsatellites, of which 71 were in the non-coding regions. Approximately 32 forward, 34 tandem, and 17 palindromic repeats were detected. The complete genome sequences, 72 shared genes, matK gene, and rbcL gene from related species generated the same phylogenetic signals, and phylogenetic analysis revealed that P. ovata formed a single clade with P. maritima and P. media. The divergence time estimation as employed in BEAST revealed that P. ovata diverged from P. maritima and P. media about 11.0 million years ago (Mya; 95% highest posterior density, 10.06-12.25 Mya). In conclusion, P. ovata had significant variation in the IR region, suggesting a more stable P. ovata plastome genome than that of other Plantaginaceae species.

Maintaining genetic integrity with high promiscuity: Frequent hybridization with low introgression in multiple hybrid zones of Melocactus (Cactaceae)

Hybridization and introgression between species in contact/hybrid zones provide important insight into the genetic and ecological mechanisms of speciation. Cactaceae represents the most important radiation of true succulent angiosperms in the New World. This diversification continues to date, with species experiencing few intrinsic barriers to gene flow and the frequent occurrence of natural hybridization. Here, we used RAD-Seq single-nucleotide polymorphism (SNP) data to investigate the genetic architecture of hybridization in four hybrid zones hosting Melocactus concinnus and four congeneric species (M. ernestii, M. glaucescens, M. paucispinus, and M. zehntneri). Our results revealed that M. concinnus is highly promiscuous in sympatric areas and hybridizes with various species distributed in Morro do Chapéu (Diamantina Plateau, Bahia), eastern Brazil. However, the contemporary genomic introgression among the investigated species is very low (c. 2-5%), confirming that even in the face of hybridization, Melocactus species maintain their genetic integrity. The genomic cline approach showed a large fraction of loci deviating from a model of neutral introgression, where most of the loci are consistent with selection favoring parental genotypes. Our results suggest the occurrence of weak premating but strong postmating reproductive isolation in the analyzed cactus species. Furthermore, as most of the Melocactus species are restricted in distribution, hybridization might negatively affect their integrity if hybrids replace the parental species.

P2668Causes and predictors of 30 and 90 days readmission after cardiac arrest: insights from the nationwide readmission database

Background

Cardiac arrest (CA) is a lethal condition with high public health burden and grave long-term implications. We aimed to evaluate the rate and predictors of readmission after CA

Methods

We used the Nationwide Readmission Database 2014 to determine patient with index admission CA by using relevant ICD-9 codes. We excluded patients <18 years and admissions in October, November, and December to allow 90 days readmission follow up. We evaluated rates and causes of 30 and 90 days readmission. We investigated disposition options for CA survivors and rates of readmissions. Multivariable analysis was done for relevant variables to demonstrated predictors of readmission.

Results

A total cohort of 71,780 patients suffered CA and survived to hospital discharge. Mean age was 63.9±15 years and 61.3% were males. Mean length of stay was 14.2±18.3 days, primary payer was Medicare 58%, 42.2% were discharged home, 33% to skilled nursing/intermediate care facility, 18.5% to home with home health services, 5% to short term hospital, and 0.8% left against medical advice (AMA). All-cause 30 and 90 days readmission rates were 18% and 28.9%, respectively. According to each disposition group 30/90 days readmission rates were; home 13.6/23%, facility 22/35.7%, home health 21/31.9%, short term hospital 16.8/24.1%, and 33.7/42.4% left AMA. The most common causes of readmission at 30 and 90 days were congestive heart failure and infection (11% each). CA on readmission was 1.5% at 30 and 90 days. The most common predictors of readmission were CHF odds ratio (OR) 1.3, (95% CI: 1.3–1.4; P<0.001), renal failure OR 1.7, (95% CI: 1.7–1.8; P<0.001), chronic lung disease OR 1.3, (95% CI: 1.2–1.; P<0.001), and depression OR 1.1 (95% CI: 1.1–1.2; P<0.001).

Conclusion

Readmissions are common at 30 and 90 days in CA survivors and are associated with high cost. CHF and infection are the most common causes of 30 and 90-day readmission, while renal failure is the strongest predictor of readmission after adjusting for unbalanced covariates. Discharge to home was the most common disposition, and had the lowest rate for readmission. Leaving AMA had the highest rate of readmission.

Complete chloroplast genome sequence of Parnassia brevistyla (Celastraceae) and phylogenetic analysis with related species

The taxonomic status of Parnassia has been widely discussed, which has been placed in more than five families, Parnassiaceae, Droseraceae, Saxifragaceae, and Celastraceae. Due to the lack of reliable genetic data, we sequenced and analyzed P. brevistyla chloroplast genome for future genetic study. The complete chloroplast genomes of Parnassia brevistyla was sequenced with NovaSeq 6000. The full length of P. brevistyla chloroplast genomes is 151,728 bp. A total of 114 unique genes, including 30 tRNA genes, four rRNA genes, and 80 protein-coding genes were found in the chloroplast genome. Using the whole chloroplast genome sequences alignment of 10 species from Celastraceae and Saxifragaceae, the phylogenetic relationship was built. The phylogenetic position of P. brevistyla was closely clustered with Celastraceae. The complete chloroplast genome of P. brevistyla provides utility information for further research of phylogenetic relationship and taxonomic status of Parnassia.

Deep Intraspecific Divergence in the Endemic Herb Lancea tibetica (Mazaceae) Distributed Over the Qinghai-Tibetan Plateau

Qinghai-Tibetan Plateau (QTP) is an important biodiversity hub, which is very sensitive to climate change. Here in this study, we investigated genetic diversity and past population dynamics of Lancea tibetica (Mazaceae), an endemic herb to QTP and adjacent highlands. We sequenced chloroplast and nuclear ribosomal DNA fragments for 429 individuals, collected from 29 localities, covering their major distribution range at the QTP. A total of 19 chloroplast haplotypes and 13 nuclear genotypes in two well-differentiated lineages, corresponding to populations into two groups isolated by Tanggula and Bayangela Mountains. Meanwhile, significant phylogeographical structure was detected among sampling range of L. tibetica, and 61.50% of genetic variations was partitioned between groups. Gene flow across the whole region appears to be restricted by high mountains, suggesting a significant role of geography in the genetic differences between the two groups. Divergence time between the two lineages dated to 8.63 million years ago, which corresponded to the uplifting of QTP during the late Miocene and Pliocene. Ecological differences were found between both the lineages represent species-specific characteristics, sufficient to keep the lineages separated to a high degree. The simulated distribution from the last interglacial period to the current period showed that the distribution of L. tibetica experienced shrinkage and expansion. Climate changes during the Pleistocene glacial-interglacial cycles had a dramatic effect on L. tibetica distribution ranges. Multiple refugia of L. tibetica might have remained during the species history, to south of the Tanggula and north of Bayangela Mountains, both appeared as topological barrier and contributed to restricting gene flow between the two lineages. Together, geographic isolation and climatic factors have played a fundamental role in promoting diversification and evolution of L. tibetica.

Westwards and northwards dispersal of Triosteum himalayanum (Caprifoliaceae) from the Hengduan Mountains region based on chloroplast DNA phylogeography

The varying topography and environment that resulted from paleoorogeny and climate fluctuations of the Himalaya–Hengduan Mountains (HHM) areas had a considerable impact on the evolution of biota during the Quaternary. To understand the phylogeographic pattern and historical dynamics of Triosteum himalayanum (Caprifoliaceae), we sequenced three chloroplast DNA fragments (rbcL-accD, rps15-ycf1, and trnH-psbA) from 238 individuals representing 20 populations. Nineteen haplotypes (H1–H19) were identified based on 23 single-site mutations and eight indels. Most haplotypes were restricted to a single population or neighboring populations. Analysis of molecular variance revealed that variations among populations were much higher than that within populations for the overall gene pool, as well as for the East Himalayan group (EH group) and the North Hengduan group (NHM group), but not for the Hengduan Mountains group (HM group). Ecoregions representing relatively high genetic diversity or high frequencies of private haplotypes were discovered, suggesting that this alpine herbaceous plant underwent enhanced allopatric divergence in isolated and fragmented locations during the Quaternary glaciations. The current phylogeographic structure of T. himalayanum might be due to heterogeneous habitats and Quaternary climatic oscillations. Based on the phylogeographic structure of T. himalayanum populations, the phylogenetic relationship of identified haplotypes and palaeodistributional reconstruction, we postulated both westwards and northwards expansion from the HM group for this species. The westwards dispersal corridor could be long, narrow mountain areas and/or the Yarlung Zangbo Valley, while the northwards movement path could be south–north oriented mountains and low-elevation valleys.

Spiroides shrubs on Qinghai-Tibetan Plateau: Multilocus phylogeography and palaeodistributional reconstruction of Spiraea alpina and S. Mongolica (Rosaceae)

A common hypothesis for the rich biodiversity found in mountains is uplift-driven diversification. Using a multilocus approach, here we assessed the influence of Qinghai-Tibetan Plateau (QTP) uplift and fluctuating regional climate on genetic diversity of two sister spiroides shrubs, Spiraea alpina and S. mongolica. Combined with palaeodistributional reconstruction modelling, we investigated the current and past-predicted distribution of these species under different climatic episodes. The study demonstrated that continuous pulses of retreat and expansion during last glacial-interglacial episodes, combined with the uplifting of QTP shaped the current distribution of these species. All the populations showed high level of genetic diversity based on both cpDNA and SSR markers. The average gene diversity within populations based on cpDNA markers was 0.383 ± 0.052 for S. alpina and 0.477 ± 0.048 for S. mongolica. The observed and expected heterozygosities based on SSR for both Spiraea alpina and S. mongolicawere H_E(0.72-0.90)/H_O(0.35-0.78) and H_E(0.77-0.92)/H_O(0.47-0.77) respectively. Palaeodistributional reconstruction indicated species' preferences at southeastern edge of the plateau during last glacial maximum, at higher altitude areas of QTP and range expansion to central plateau during the interglacial episodes. Assignment tests in STRUCTURE, discriminant analysis of principal coordinates and Immigrants analysis in GENECLASS based on nuclear SSR markers did not support the hypothesis of gene flow between both the species. However, maximum likelihood approach based on cpDNA showed sharing of haplotypes between both species.

A comparison of stimulus dosing methods for electroconvulsive therapy

Aims and Methods

A prospective study comparing initial electroconvulsive therapy treatment doses determined by empirical dose titration with estimates derived from two simple dose prediction methods and a fixed-dose regimen (275 mC).

Results

Thirty-three patients had seizure thresholds between 25 mC and 403 mC. The dose titration method led to a mean initial treatment dose of 195 mC that was intermediate between those predicted by the age method (275 mC) and the half-age method (137 mC). Estimates were within acceptable limits in 33% of cases for the age method, 64% for the half-age method and 40% for the fixed-dose method.

Clinical Implications

Either dose prediction or dose titration methods may be more appropriate in different clinical situations. The half-age method appears to be a more accurate predictor of optimum initial treatment dose.

Patterns of superior articular facet and morphometric study of Nepalese dry Calcanei

Introduction: The three important articulating facets in the superior aspect of the calcaneum are the anterior, middle and posterior articulating facet. Descriptions of the posterior talar facet on the dorsum of the calcaneus are similar. However, there are differences when facet for the head of the talus on the calcaneus is considered. Four types (pattern I, II, III, IV) of calcaneus having different talar facets are reported in the literature. Objective: This study aims to describe the calcaneal bone by measuring its dimensions and determining the variations of talar articulating facet. Materials and methods: Overall 142 calcanei (68 right, 74 left) with unidentified gender, were assessed. Vernier calipers and Goniometry were used. Results: In this study Type I calcaneus (56.34 %) was the most prevalent type with Type II calcaneus (42.25 %) as the second most common type followed by Type IV (1.41 %) as the third frequently found pattern of calcaneus. Conclusion: Type I calcaneus was the most frequent type in the Nepalese showing similarity to the results of the studies performed in Spanish, American, African and various Indian population. Bohler's angle of the right and left calcanei was 34.92° ± 8.09° and 35.4° ± 7.30° respectively. Development of database of calcaneal measurements in various populations is recommended.

Prevalence of psychological distress and its association with socio-demographic and HIV-risk factors in South Africa: Findings of the 2012 HIV prevalence, incidence and behaviour survey

BACKGROUND

In South Africa, there are limited nationally representative data on the prevalence and factors associated with psychological distress. This study used a 2012 nationally representative population-based household survey to investigate factors associated with psychological distress in South Africa.

METHODS

The survey is based on a multistage stratified cross-sectional design. Univariate and multivariate logistic regression models were fitted to identify factors associated with psychological distress.

RESULTS

Out of a total 25860 participants, 23.9% reported psychological distress. Higher likelihood of reporting psychological distress was significantly associated with being female [OR = 1.68 (95% CI: 1.34-2.10), p < 0.001], aged 25 to 49 years [OR = 1.35 (95% CI: 1.08-1.70), p = 0.010] and 50 years and older [OR = 1.44 (95% CI: 1.06-1.97), p = 0.023)], Black Africans [OR = 1.61 (95% CI: 1.24-2.10), p < 0.001)], a high risk drinker [OR = 1.37 (95% CI: 1.02-1.83), p = 0.037], a hazardous drinker [OR = 4.76 (95% CI: 2.69-8.42), p < 0.001] and HIV positive, [OR = 1.79 (95% CI:1.55-2.08) p < 0.001], while lower likelihood of reporting psychological distress was significantly associated with being married [OR = 0.78 (95% CI: 0.62-0.98), p = 0.031), employed [OR = 0.71 (95% CI: 0.57-0.88), p = 0.002], and living in a rural formal area [OR = 0.73 (95% CI: 0.55-0.97), p = 0.033].

CONCLUSION

There is a need to develop strategies to alleviate psychological distress in the general population, with a particular focus on those who may be more vulnerable to distress such as females, the aged, excessive alcohol users, the unemployed, people living with HIV and those residing in urban areas as identified in the current findings.

Intimate partner violence as a factor associated with risky sexual behaviours and alcohol misuse amongst men in South Africa

Globally intimate partner violence (IPV) is a public health problem that can be perpetrated by both males and females, although males are more likely to inflict severe IPV-related injuries on their female partners. In low- and middle-income countries like South Africa, few studies have conducted research to determine whether IPV perpetration by men may be a risk factor for engaging in other risk behaviours. The aim of this study is to determine whether IPV perpetration by men is a risk factor for engaging in other risk behaviours with a particular focus on risky sexual behaviours and alcohol misuse. The data for this study were drawn from a multilevel intervention study, which addressed the nexus of alcohol abuse and HIV prevention among men in South Africa. Men were screened and recruited from informal drinking places within 12 communities situated in one of the oldest, predominantly Xhosa-speaking African townships in Cape Town. Univariate and multivariate logistic regression models were used to analyse the associations between IVP and potential explanatory variables. Of the 975 men included in the survey, 39.9% reported to have been involved in Intimate Partner Violence. IPV perpetration was significantly more likely among men who reported having a child [OR 1.51 (1.07-2.14) p = .019], having a casual sexual partner [OR 1.51 (1.11-2.05) p = .008], and those with possible alcohol dependence [OR 3.46 (1.17-10.20) p = .024]. IPV was significantly less likely among men with matric educational qualification than those with no education [OR 0.30 (95% CI: 0.09-1.02) p = .053] and among those who reported using a condom at last sex [OR 0.69 (0.50-0.97) p = .034]. We therefore recommend that interventions aimed at reducing IPV need to address risky sexual and drinking behaviours amongst men simultaneously, while also focusing on intimate relationship power dynamics and gendered norms amongst couples.

Development and characterization of polymorphic microsatellite loci for Saxifraga egregia (Saxifragaceae)

PREMISE OF THE STUDY

Saxifraga egregia (Saxifragaceae) is a perennial herb that is endemic to the Qinghai-Tibet Plateau. We developed 12 polymorphic microsatellite loci for S. egregia to investigate its population genetics.

METHODS AND RESULTS

Forty-eight pairs of microsatellite primers (including 36 monomorphic loci) were isolated and characterized by magnetic bead enrichment. Twelve of these markers showed polymorphism, and the number of alleles per locus ranged from four to 14 across 50 individuals from three populations of S. egregia. No linkage disequilibrium was detected in any pair of loci.

CONCLUSIONS

These polymorphic markers are expected to be helpful in further studies on the systematics and phylogeography of S. egregia in the Qinghai-Tibet Plateau.

Isolation of microsatellite loci for Rhodiola alsia (Crassulaceae), an important ethno-medicinal herb endemic to the Qinghai-Tibetan plateau

Rhodiola alsia, which has been used widely in traditional Chinese medicine for a considerable time, grows on moist habitats at high altitude near the snow line. Microsatellite loci were developed for R. alsia to investigate its population genetics. In total, 17 polymorphic microsatellites were developed based on ESTs from the Illumina HiSeq(TM) 2000 platform. The microsatellite loci were checked for variability using 80 individuals of R. alsia sampled from four locations on the Qinghai-Tibet Plateau. The total number of alleles per locus ranged from 10 to 20, and the observed heterozygosity ranged from 0.000 to 1.000. The null allele frequency ranged from 0.000 to 0.324. These microsatellites are expected to be helpful in future studies of population genetics in R. alsia and related species.

Comparative transcriptome analysis of aboveground and underground tissues of Rhodiola algida, an important ethno-medicinal herb endemic to the Qinghai-Tibetan Plateau

Transcriptome sequencing is a powerful tool for the assessment of gene expression and the identification and characterization of molecular markers in non-model organisms. Rhodiola algida L. (Crassulaceae), endemic to the Qinghai-Tibetan Plateau, has long been used in traditional Chinese medicine to prevent altitude sickness and eliminate fatigue. Illumina-based high-throughput transcriptome sequencing of aboveground and underground tissues of R. algida respectively yielded 5.40 million and 5.18 million clean reads. A total of 82,664 unigenes averaging 577 bp in length were generated from the aboveground clean reads, with 86,237 unigenes of 502-bp mean length obtained from the underground tissues. Of 55,028 unigenes compared with sequences in UniProt databases, 20,413 unigenes had significant similarities with existing sequences in NR, NT, Swiss-Prot, GO, KEGG, and COG databases. Single nucleotide polymorphism (SNP) analysis identified 237,294 SNPs from 154,636 contigs of aboveground tissues and 197,540 SNPs from 144,963 underground-derived contigs. The information uncovered in this study should serve as a valuable resource for the characterization of important traits related to secondary metabolite formation and for the identification of associated molecular mechanisms.

Isolation of 16 microsatellite markers for Spiraea alpina and S. mongolica (Rosaceae) of the Qinghai-Tibet Plateau

PREMISE OF THE STUDY

A set of microsatellite markers were developed to characterize the level of genetic diversity and gene flow in two plant species endemic to the Qinghai-Tibet Plateau, Spiraea alpina and S. mongolica. •

METHODS AND RESULTS

Using the Fast Isolation by AFLP of Sequences COntaining repeats (FIASCO) method, 16 microsatellite loci showed polymorphisms in both species. In two populations of each species, the number of alleles per locus ranged from three to 18 in S. alpina and from four to 30 in S. mongolica. •

CONCLUSIONS

These microsatellite markers provide an efficient tool for population genetic studies and will be used to assess the genetic diversity and spatial genetic structure of S. alpina and S. mongolica.