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1.
Astrobiology ; 2024 May 02.
Article in English | MEDLINE | ID: mdl-38696654

ABSTRACT

Ribose is the defining sugar in ribonucleic acid (RNA), which is often proposed to have carried the genetic information and catalyzed the biological reactions of the first life on Earth. Thus, abiological processes that yield ribose under prebiotic conditions have been studied for decades. However, aqueous environments required for the formation of ribose from materials available in quantity under geologically reasonable models, where the ribose formed is not immediately destroyed, remain unclear. This is due in large part to the challenge of analysis of carbohydrates formed under a wide range of aqueous conditions. Thus, the formation of ribose on prebiotic Earth has sometimes been questioned. We investigated the quantitative effects of pH, temperature, cation, and the concentrations of formaldehyde and glycolaldehyde on the synthesis of diverse sugars, including ribose. The results suggest a range of conditions that produce ribose and that ribose could have formed in constrained aquifers on prebiotic Earth.

2.
Biodivers Data J ; 12: e119476, 2024.
Article in English | MEDLINE | ID: mdl-38655011

ABSTRACT

Background: The genus Monoctonus Haliday, 1833 is a small group which consists of 24 species worldwide. In South Korea, Chang and Youn (1983) recorded one species, M.similis Starý & Schlinger, 1967, but the evidence for identification of this species is doubtful and further confirmation is required (personal communication with Prof. Jong-Cheol Paik). New information: An additional Monoctonus species is recorded as new to science from South Korea. Descriptions and illustrations of the new species -Monoctonuskoreanus sp. nov. - are provided, together with its mitochondrial cytochrome c oxidase subunit I (COI) data and phylogenetic position. A key to the female of the two species present in Korea is provided.

3.
Biodivers Data J ; 12: e118599, 2024.
Article in English | MEDLINE | ID: mdl-38524900

ABSTRACT

Background: The genus Trioxys Haliday, 1833 consists of more than 80 species worldwide with three species being recorded in South Korea. In this study, we report the first observation of the two additional species, T.liui Chou & Chou, 1993 from Takecallisarundinariae (Essig, 1917) on Phyllostachysbambusoides Siebold & Zucc., 1843 and T.remaudierei Starý & Rakhshani, 2017 from T.taiwana (Takahashi, 1926) on Sasaborealis (Hack.) Makino & Shibata, 1901. New information: Trioxysliui and T.remaudierei are described and reported with phototographs of the diagnostic morphological characters and the mitochondrial cytochrome c oxidase subunit I (COI) data (barcode region) and Bayesian tree of the phylogenetic analysis amongst the closely-related taxa are provided.

4.
Zookeys ; 1193: 219-243, 2024.
Article in English | MEDLINE | ID: mdl-38496801

ABSTRACT

Four new species, Xynobiusazoniussp. nov., X.brevifemorasp. nov., X.duoferussp. nov., and X.stipitoidessp. nov., are described and illustrated, and one species X.geniculatus (Thomson, 1895) is newly reported from South Korea. Xynobiusgeniculatus (Thomson, 1895) is redescribed and illustrated, and a new combination, Xynobius (Stigmatopoea) cubitalis (Fischer, 1959), comb. nov. is suggested. An identification key to the Xynobius species known from South Korea is provided.

5.
Zookeys ; 1160: 61-74, 2023.
Article in English | MEDLINE | ID: mdl-37180818

ABSTRACT

Two new and very similar species of the genus Xynobius Foerster, 1863 are described and illustrated, X.subparallelus Han & van Achterberg, sp. nov. from Japan (Honshu) and X.setosiscutum van Achterberg, sp. nov. from Norway. Three species are newly reported from Norway: Xynobiusaciculatus (Thomson, 1895), X.comatus (Wesmael, 1835), and X.polyzonius (Wesmael, 1835). X.polyzonius (Wesmael, 1835) and X.sapporanus (Fischer, 1963) are new combinations. Identification keys to the Xynobius species known from Norway and Japan are added.

6.
J Am Chem Soc ; 2023 Apr 10.
Article in English | MEDLINE | ID: mdl-37036666

ABSTRACT

Chemists have now synthesized new kinds of DNA that add nucleotides to the four standard nucleotides (guanine, adenine, cytosine, and thymine) found in standard Terran DNA. Such "artificially expanded genetic information systems" are today used in molecular diagnostics; to support directed evolution to create medically useful receptors, ligands, and catalysts; and to explore issues related to the early evolution of life. Further applications are limited by the inability to directly sequence DNA containing nonstandard nucleotides. Nanopore sequencing is well-suited for this purpose, as it does not require enzymatic synthesis, amplification, or nucleotide modification. Here, we take the first steps to realize nanopore sequencing of an 8-letter "hachimoji" expanded DNA alphabet by assessing its nanopore signal range using the MspA (Mycobacterium smegmatis porin A) nanopore. We find that hachimoji DNA exhibits a broader signal range in nanopore sequencing than standard DNA alone and that hachimoji single-base substitutions are distinguishable with high confidence. Because nanopore sequencing relies on a molecular motor to control the motion of DNA, we then assessed the compatibility of the Hel308 motor enzyme with nonstandard nucleotides by tracking the translocation of single Hel308 molecules along hachimoji DNA, monitoring the enzyme kinetics and premature enzyme dissociation from the DNA. We find that Hel308 is compatible with hachimoji DNA but dissociates more frequently when walking over C-glycoside nucleosides, compared to N-glycosides. C-glycocide nucleosides passing a particular site within Hel308 induce a higher likelihood of dissociation. This highlights the need to optimize nanopore sequencing motors to handle different glycosidic bonds. It may also inform designs of future alternative DNA systems that can be sequenced with existing motors and pores.

7.
Front Insect Sci ; 3: 1154651, 2023.
Article in English | MEDLINE | ID: mdl-38469524

ABSTRACT

Anastatus orientalis, native to northern China, is an egg parasitoid wasp of the spotted lanternfly (Lycorma delicatula) and is being tested as a potential biological control agent for invasive L. delicatula in the United States. As a component of these evaluations, live A. orientalis collected from Beijing and Yantai in China were reared in containment in the U.S. These specimens showed different responses in diapause behaviors to rearing conditions used previously by other researchers. To understand the primary mechanism potentially driving discrepancies in important life history traits, we used molecular tools to examine the genetic composition of A. orientalis from China and from South Korea, where the parasitoid has been introduced to aid in the population management of invasive L. delicatula. Molecular analysis of mitochondrial DNA recovered six haplotype groups, which exhibit biased frequency of abundance between collection sites. Some haplotypes are widespread, and others only occur in certain locations. No apparent pattern is observed between wasps collected from different years or emergence seasons. Uncorrected genetic distances between haplotype groups range from 0.44% to 1.44% after controlling for within-group variation. Genetic variance of A. orientalis is characterized by high levels of local diversity that contrasts with a lack of a broad-scale population structure. The introduced Korean population exhibits lower genetic diversity compared to native populations. Additionally, we created iso-female lines for major haplotype groups through laboratory rearing. Differences in diapause behavior were correlated with mitochondrial haplotype. Our results indicate that the observed life history traits in A. orientalis have a genetic base.

8.
Insects ; 13(10)2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36292830

ABSTRACT

We compared the population genetic structure between populations of the blueberry gall midge-Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae)-from blueberry and cranberry and determined the genetic relationships among geographical subgroups by genotyping 632 individuals from 31 different populations from their native USA regions (New Jersey, Michigan, and Georgia) and from invaded Korean regions using 12 microsatellite loci. Our population genetic analyses showed a clear separation between the two host-associated D. oxycoccana populations from blueberry and cranberry. Using data from only the blueberry-associated D. oxycoccana populations, we identified five genetically isolated subgroups. An analysis of the approximate Bayesian computation suggests that the invasive D. oxycoccana population from Korea appears to have been introduced from an unsampled source population rather than directly from its native range. Our findings will allow for an easier identification of the source of D. oxycoccana into newly invaded regions, as well as to determine their association with blueberry and cranberry, which based on our results can be considered as two distinct species.

9.
Astrobiology ; 22(6): 629-636, 2022 06.
Article in English | MEDLINE | ID: mdl-35588195

ABSTRACT

Reported here are experiments that show that ribonucleoside triphosphates are converted to polyribonucleic acid when incubated with rock glasses similar to those likely present 4.3-4.4 billion years ago on the Hadean Earth surface, where they were formed by impacts and volcanism. This polyribonucleic acid averages 100-300 nucleotides in length, with a substantial fraction of 3',-5'-dinucleotide linkages. Chemical analyses, including classical methods that were used to prove the structure of natural RNA, establish a polyribonucleic acid structure for these products. The polyribonucleic acid accumulated and was stable for months, with a synthesis rate of 2 × 10-3 pmoles of triphosphate polymerized each hour per gram of glass (25°C, pH 7.5). These results suggest that polyribonucleotides were available to Hadean environments if triphosphates were. As many proposals are emerging describing how triphosphates might have been made on the Hadean Earth, the process observed here offers an important missing step in models for the prebiotic synthesis of RNA.


Subject(s)
Earth, Planet , RNA , Catalysis , Glass , RNA/chemistry
10.
Zookeys ; 1097: 209-216, 2022.
Article in English | MEDLINE | ID: mdl-36761684

ABSTRACT

Separatatusmegagnathus sp. nov. is recorded as new to science from South Korea. Due to this record, the genus Separatatus Chen & Wu, 1994 (Braconidae: Alysiinae) is recognized for the first time from South Korea. The genus and species are described and illustrated herein plus an identification key including the Korean new species is provided. In addition, the DNA barcode region of the mitochondrial cytochrome c oxidase subunit I (COI) has been analyzed for the new species.

11.
Zookeys ; 1070: 31-40, 2021.
Article in English | MEDLINE | ID: mdl-34819769

ABSTRACT

The species of the genus Hylcalosia Fischer, 1967 (Braconidae: Alysiinae) from South Korea are revised. One species, Hylcalosiabicolor sp. nov., is new to science. They are described and illustrated herein and an identification key to the Korean species is added. In addition, the DNA barcode region of the mitochondrial cytochrome c oxidase subunit I (COI) has been analysed for the new species and H.sutchanica is used for genetic comparison.

12.
Insects ; 12(10)2021 Sep 22.
Article in English | MEDLINE | ID: mdl-34680620

ABSTRACT

To infer the introduction sources of the oriental fruit fly, Bactrocera dorsalis, we used a mitochondrial marker to reconstruct the haplotype network and 15 microsatellite loci to reveal genetic structure and relationships between the geographically or temporally different collections from Asia. We performed Approximate Bayesian computations to infer a global origin and a source of the quarantine collections found in Korea. As a result, the 40 populations were divided into three groups, of which genetic similarity is not related to the geographic vicinity. Korean samples had a similar genetic structure to Taiwan and Thailand ones. Our results suggest that the place of origin of the B. dorsalis specimens found in Korea's border quarantine is likely to be Taiwan or Thailand. As the global origin of B. dorsalis, we estimated that Taiwan and Thailand were most likely the global origins of Southeast Asian populations by testing hypothetical scenarios by the approximate Bayesian computation analyses. Our results will allow easier identification of the source region of the forthcoming invasion of quarantined B. dorsalis specimens.

13.
Insects ; 12(6)2021 Jun 10.
Article in English | MEDLINE | ID: mdl-34200556

ABSTRACT

Lycorma delicatula (White) suddenly arrived in Korea where it rapidly spread out in the central region of Korea and caused serious damage to grape vineyards. To trace the source region of its invasiveness, population genetic structures were compared between the native region, China, and the introduced regions, Korea and Japan. We examined 762 individuals from 38 different population collections using 15 microsatellite loci. Both principal coordinate and structure analyses displayed that the Chinese populations were separated into three subgroups which were located significantly far apart from each other. Among them, the Shanghai population was located closest to most Korean populations. Based on the genetic relationships and structures, it was revealed that the multiple introductions into Korea occurred at least three times. In addition, the Shanghai population was strongly estimated to be a source of initial invasive populations of Korea. In addition, analysis of the approximate Bayesian computation suggested simultaneous spread from two distant locations early in the invasion by artificial transportation of the host plants bearing egg masses. Our population genetics study can provide a precedent case with regards to identifying spreads by anthropogenic outcomes in other invasive regions.

14.
Medicina (Kaunas) ; 57(5)2021 May 12.
Article in English | MEDLINE | ID: mdl-34066172

ABSTRACT

INTRODUCTION: Leriche syndrome is an aortoiliac occlusive disease caused by atherosclerotic occlusion. We report a case of Leriche syndrome with a fracture that was suspected as complex regional pain syndrome (CRPS), as the post-traumatic pain gradually worsened in the form of excruciating neuropathic pain. CASE REPORT: A 52-year-old woman with a history of hypertension was referred to the Department of Pain Medicine from a local orthopedic clinic because of suspected CRPS for excruciating neuropathic pain for one month. She complained of gait dysfunction and severe pain in the right foot following an incident of trauma with the right first toe. The average pain intensity assessed using the visual analog scale (VAS) was 90 (0: no pain, 100: the worst pain imaginable), and the neuropathic pain was evident as a score of 6/10 on Douleur neuropathique 4. Allodynia, hyperalgesia, blue discoloration of the skin, asymmetric temperature change (1.38 °C), and edematous soft tissue changes were observed. Ultrasonography showed a chip fracture in the first distal phalanx of the right first toe. The diagnosis was most probably CRPS type I according to the Budapest research criteria for CRPS. However, multiple pain management techniques were insufficient in controlling the symptoms. A month and a half later, an ankle-brachial index score of less than 0.4 suggested severe peripheral artery disease. Computed tomography angiography showed total occlusion between the infrarenal abdominal aorta and the bilateral common iliac arteries. Therefore, she underwent aortic-bifemoral bypass surgery with a diagnosis of Leriche syndrome. Three months after the surgery, the average pain intensity was graded as 10 on the VAS (0-100), the color of the skin of the right first toe improved and no gait dysfunction was observed. CONCLUSION: A chip fracture in a region with insufficient blood flow could manifest as excruciating neuropathic pain in Leriche syndrome.


Subject(s)
Complex Regional Pain Syndromes , Leriche Syndrome , Neuralgia , Aorta, Abdominal , Complex Regional Pain Syndromes/diagnosis , Complex Regional Pain Syndromes/etiology , Diagnostic Errors , Female , Humans , Leriche Syndrome/complications , Leriche Syndrome/diagnosis , Middle Aged , Neuralgia/diagnosis , Neuralgia/etiology
15.
Zookeys ; 1022: 51-64, 2021.
Article in English | MEDLINE | ID: mdl-33762867

ABSTRACT

The species of the genus Cratospila Foerster, 1863 (Braconidae, Alysiinae) from South Korea are revised, and the genus is recorded for the first time from South Korea. All four species are new to science, and Cratospila albifera sp. nov., C. ejuncida sp. nov., C. luteocephala sp. nov., and C. syntoma sp. nov. are described and illustrated herein. In addition, COI has been sequenced of three species. A key to the Korean species is provided.

16.
Astrobiology ; 21(3): 298-306, 2021 03.
Article in English | MEDLINE | ID: mdl-33533695

ABSTRACT

While nucleoside 5'-triphosphates are precursors for RNA in modern biology, the presumed difficulty of making these triphosphates on Hadean Earth has caused many prebiotic researchers to consider other activated species for the prebiotic synthesis of RNA. We report here that nickel(II), in the presence of borate, gives substantial amounts (2-3%) of nucleoside 5'-triphosphates upon evaporative heating in the presence of urea, salts, and cyclic trimetaphosphate (CTMP). Also recovered are nucleoside 5'-diphosphates and nucleoside 5'-monophosphates, both likely arising from 5'-triphosphate intermediates. The total level of 5'-phosphorylation is typically 30%. Borate enhances the regiospecificity of phosphorylation, with increased amounts of other phosphorylated species seen in its absence. Experimentally supported paths are already available to make nucleosides in environments likely to have been present on Hadean Earth soon after a midsized 1021 to 1023 kg impactor, which would also have delivered nickel to the Hadean surface. Further, sources of prebiotic CTMP continue to be proposed. Thus, these results fill in one of the few remaining steps needed to demystify the prebiotic synthesis of RNA and support a continuous model from atmospheric components to oligomeric RNA that is lacking only a mechanism to obtain homochirality in the product RNA.


Subject(s)
Borates , Nucleosides , Nickel , Nucleotides , RNA
17.
PLoS One ; 16(2): e0245604, 2021.
Article in English | MEDLINE | ID: mdl-33539375

ABSTRACT

Aphids provide a good model system to understand the ecological speciation concept, since the majority of the species are host-specific, and they spend their entire lifecycle on certain groups of host plants. Aphid species that apparently have wide host plant ranges have often turned out to be complexes of host-specialized biotypes. Here we investigated the various host-associated populations of the two recently diverged species, Aphis gossypii and A. rhamnicola, having multiple primary hosts, to understand the complex evolution with host-associated speciation. Using mitochondrial DNA marker and nine microsatellite loci, we reconstructed the haplotype network, and analyzed the genetic structure and relationships. Approximate Bayesian computation was also used to infer the ancestral primary host and host-associated divergence, which resulted in Rhamnus being the most ancestral host for A. gossypii and A. rhamnicola. As a result, Aphis gossypii and A. rhamnicola do not randomly use their primary and secondary host plants; rather, certain biotypes use only some secondary and specific primary hosts. Some biotypes are possibly in a diverging state through specialization to specific primary hosts. Our results also indicate that a new heteroecious race can commonly be derived from the heteroecious ancestor, showing strong evidence of ecological specialization through a primary host shift in both A. gossypii and A. rhamnicola. Interestingly, A. gossypii and A. rhamnicola shared COI haplotypes with each other, thus there is a possibility of introgression by hybridization between them by cross-sharing same primary hosts. Our results contribute to a new perspective in the study of aphid evolution by identifying complex evolutionary trends in the gossypii sensu lato complex.


Subject(s)
Aphids/genetics , Evolution, Molecular , Host-Pathogen Interactions/genetics , Hybridization, Genetic , Sympatry , Animals , Bayes Theorem , DNA, Mitochondrial/genetics , Genetic Loci , Genetic Variation , Haplotypes , Microsatellite Repeats/genetics , Rhamnus/genetics
18.
Anesth Pain Med ; 11(5): e118627, 2021 Oct.
Article in English | MEDLINE | ID: mdl-35075414

ABSTRACT

BACKGROUND: When performing spinal anesthesia for cesarean section, it is important to determine the appropriate anesthetic dose as well as to predict the level of spinal anesthesia. In this study, it was hypothesized that some anthropometric measurements may be related to maximum sensory block and hemodynamic changes. OBJECTIVES: The aim of this study are to find maternal anthropometric values that are correlate with the level of spinal anesthesia. METHODS: Maternal anthropometric measurements, including height, weight, supine and standing abdominal circumference (AC), and hip circumference, were recorded before spinal anesthesia for cesarean section. Spinal anesthesia was induced by administering 8 mg of 0.5% hyperbaric bupivacaine and 20 µg of fentanyl at the L3-L4 interspace. The level of sensory block was determined using pin-prick at 1, 5, 10, and 15 minutes after spinal anesthesia. The sensory block level and hemodynamic adverse events were analyzed in relationship to anthropometric measurements. RESULTS: The supine AC/height ratios significantly correlate with the maximal sensory block level at 5, 10, and 15 minutes after the injection of spinal anesthetic (P = 0.001, P < 0.001 and P < 0.001, respectively). Further, there were significant correlations between body mass index (BMI) and sensory block level at every assessment (P = 0.041, P = 0.002, P = 0.001 and P < 0.001, respectively). When comparing the groups with and without hypotension, BMI, weight, and supine AC/height ratio were found to be significantly higher in the group with hypotension (P = 0.002, P = 0.004 and P = 0.006, respectively). CONCLUSIONS: We conclude that BMI and AC/height ratio correlate with the sensory block level of spinal anesthesia for cesarean section.

19.
Medicine (Baltimore) ; 99(28): e20946, 2020 Jul 10.
Article in English | MEDLINE | ID: mdl-32664094

ABSTRACT

BACKGROUND: The beach chair position (BCP), used during shoulder surgery, is associated with hypotension, bradycardia, and risk of cerebral hypoperfusion. Phenylephrine is commonly used as a first treatment of choice of intraoperative hypotension during surgery. We evaluated the hemodynamic effects of 2 doses of intravenous phenylephrine infusion administered before being placed in BCP for arthroscopic shoulder surgery. The primary endpoint was the incidence of hypotension after positional change. METHODS: Sixty-six patients were randomized to receive either intravenous normal saline (group NS) or intravenous phenylephrine infusion (0.5 µg/kg/min, group LP or 1.0 µg/kg/min, group HP) for 5 minutes before being placed in the BCP. Mean arterial pressure(MAP), heart rate, stroke volume variation, and cardiac index were measured before and after positional change. RESULTS: The total incidence of hypotension after the BCP was 93.65%, but was not significantly different among the 3 groups. However, there was a significant difference in trends between the groups for MAP for 5 minutes after BCP (P = .028). Comparison of changes in MAP at 1 minute compared to post-induction MAP was significantly different between group HP and group NS (P = .014). CONCLUSION: Infusion of 0.5 and 1.0 µg/kg/min of phenylephrine for 5 minutes before the BCP has no preventive effect for incidence of hypotension. However, this study showed that 1.0 µg/kg/min of phenylephrine infusion for 5 minutes can attenuate the severity of hypotension.


Subject(s)
Hypotension/etiology , Hypotension/prevention & control , Intraoperative Complications/etiology , Intraoperative Complications/prevention & control , Patient Positioning/adverse effects , Phenylephrine/administration & dosage , Aged , Female , Humans , Hypotension/epidemiology , Incidence , Infusions, Intravenous , Male , Middle Aged , Prospective Studies , Single-Blind Method
20.
Medicine (Baltimore) ; 99(20): e20001, 2020 May.
Article in English | MEDLINE | ID: mdl-32443302

ABSTRACT

Elderly patients with femoral fractures are anticipated to endure the most pain caused by positional changes required for spinal anesthesia. To improve pain relief, we compared the analgesic effects of intravenous dexmedetomidine-ketamine and dexmedetomidine-fentanyl combinations to facilitate patient positioning for spinal anesthesia in elderly patients with proximal femoral fractures. Forty-six patients were randomly assigned to two groups and received either 1 mg/kg of intravenous ketamine (group K) or 1 µg/kg of intravenous fentanyl (group F) concomitant with a loading dose of dexmedetomidine 1 µg/kg over 10 minutes, then dexmedetomidine infusion only was continued at 0.6 µg/kg/h for following 20 minutes, and titrated at a rate of 0.2 to 0.6 µg/kg/h until the end of surgery. After completion of the infusion of either ketamine or fentanyl, the patients were placed in the lateral position with the fracture site up. The pain score (0 = calm, 1 = facial grimacing, 2 = moaning, 3 = screaming, and 4 = unable to proceed because of restlessness or agitation) was used to describe the pain intensity in each step during the procedure (lateral positioning, hip flexion, and lumbar puncture), and quality score (0 = poor hip flexion, 1 = satisfactory hip flexion, 2 = good hip flexion, and 3 = optimal hip flexion) was used to describe the quality of posture. Group K showed a median pain score of 0 (0-1), 0 (0-0) and 0 (0-0) in lateral positioning, hip flexion and lumbar puncture, respectively, while group F showed a score of 3 (2.75-3), 3 (2-3) and 0 (0-1), respectively. The pain score in lateral positioning (P < .0001) and hip flexion (P < .0001) was significantly lower in group K than group F. Group K showed the significantly higher quality scores of spinal anesthesia positioning (P = .0044) than group F. Hemodynamic adverse effects, such as bradycardia, hypotension, and desaturation, were not significantly different between the groups. The administration of dexmedetomidine-ketamine showed a greater advantage in reducing pain intensity and increasing the quality with patient positioning during spinal anesthesia in elderly patients with proximal femoral fractures, without any serious adverse effects.


Subject(s)
Analgesia/methods , Analgesics/administration & dosage , Anesthesia, Spinal , Hip Fractures/surgery , Patient Positioning , Aged , Aged, 80 and over , Dexmedetomidine/administration & dosage , Double-Blind Method , Female , Fentanyl/administration & dosage , Humans , Ketamine/administration & dosage , Male
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