Disentangling earthworm taxonomic stumbling blocks using molecular markers

Taxonomic classification of earthworms based on anatomical features has created several challenges for systematics and population genetics. This study examines the application of molecular markers, in particular mitochondrial cytochrome oxidase (COI), to facilitate discrimination of closely related earthworm species. Molecular markers have also provided insights into population genetics by aiding assessment of genetic diversity, lineage sorting, and genealogical distributions of populations for several species. Phylogeography—a study that evaluates the geographical distribution of these genealogical lineages and the role of historical processes in shaping their distribution—has also provided insights into ecology and biodiversity. Such studies are also essential to understand the distribution patterns of invasive earthworm species that have been introduced in non-native ecosystems globally. The negative consequences of these invasions on native species include competition for food resources and altered ecosystems. We anticipate that molecular markers such as COI and DNA barcoding offer potential solutions to disentangling taxonomic impediments in earthworms and advancing their systematics and population genetics. 

Three uncharted endemic earthworm species of the genus Eutyphoeus (Oligochaeta: Octochaetidae) from Mizoram, India

Integrative approach of taxonomy drives us to the discovery of three new species of the genus Eutyphoeus Michaelsen 1900, namely Eutyphoeus phawngpuiensis sp. nov., Eutyphoeus serei sp. nov. and Eutyphoeus tawi sp. nov. from protected forests of Mizoram, India. E. phawngpuiensis sp. nov. belongs to the Eutyphoeus hastatus group, and is characterized by holandric male organs, having spermathecal pores at a or ab, bidiverticulate spermathecae, and lack of genital marking glands. While, E. tawi sp. nov. has spermathecal pores at b or lateral to b, without lateral intestinal caeca. E. serei sp. nov. belongs to the Eutyphoeus gigas group, and is distinguished by having metandric male organs, lacking female pore of right side, and having spoon shaped tip of penial setae without ornamentation. Molecular characterization using coi gene marker also supports the findings. The maximum intraspecific distances and distance to the nearest neighbour of E. phawngpuiensis sp. nov., E. serei sp. nov. and E. tawi sp. nov. were recorded 3.5%, 9.37%; 2.35%, 14.83%; and 2.28%, 12.86% respectively. The key to Eutyphoeus species of India was also updated.

Amiodarone use in elderly atrial fibrillation patients with preserved ejection fraction is associated with increased short-term mortality

Background

Amiodarone is commonly used in atrial fibrillation (AF). Long-term use of amiodarone is associated with significant toxicities, especially in elderly patients. However, in the short term after hospitalization of AF, it remains uncertain whether the use of amiodarone will increase mortality.

Methods

We conducted a retrospective cohort study including patients (Age≥60 years old) who were hospitalized between 07/01/2004 and 06/30/2019 with a primary diagnosis of AF and left ventricular ejection fraction (LVEF) ≥50%. Patients who were prescribed amiodarone during hospitalization but not before are considered as amiodarone group (348 patients). Patients who weren't prescribed amiodarone are considered as non-amiodarone group (2260 patients).

Univariate analysis solely analyzed amiodarone use on the all-cause mortality (Kaplan-Meier Curve), and possible confounders were adjusted in the multivariate analysis including age, gender, diabetes mellitus (DM), hypertension (HTN), coronary artery disease (CAD), as well as LVEF, left atrium internal diameter, use of other rate control medications (e.g. beta-blocker). The proportional-hazard assumption was tested by Log-rank test and a 2-sided P value of <0.05 is considered statistically significant. The hazard ratio and 95% confidence interval (CI) were calculated.

Results

Patients' baseline characteristics were listed in Table 1. Both Univariate and Multivariate analysis showed amiodarone group had higher in-hospital (hazard ratio 2.06; p=0.036) and 100-day mortality (hazard ratio 1.86; p=0.028). Other rate control medication use was also associated with increased mortality but not statistically significant. The results are showed in Figure 1.

Conclusion

Amiodarone use in elderly patients with preserved ejection fraction is associated with increased short-term all-cause mortality after hospitalization of AF.

Figure 1. KM Curve & ForestPlot of Mortality

Funding Acknowledgement

Type of funding source: None

Exploring new records of Eutyphoeus sp. (haplotaxida: Octochaetidae) from garo hills, Meghalaya, North Eastern state of India with use of DNA barcodes

The work was aimed to investigate earthworms species particularly Eutyphoeus endemic to India with the use of DNA barcodes and usual morpho-anatomical standards of earthworm taxonomy from protected areas of Garo Hills, Meghalaya, the north-east region (NER) of India. The study revealed two new records Eutyphoeus kempi Stephenson, E. nepalensis Michaelsen and confirms availability of three known sp. namely E. callosus Gates, E. gammiei Beddard and E. turaensis Stephenson. The neighbor-joining tree was constructed using the K2P substitution model and the genomic signature of each species using COI-1 gene was generated for the first time and were used to reconfirm the identification of species.

Recurrent hypoglycemia, a rare case of insulin autoimmune syndrome in a young African American male

Insulin autoimmune syndrome (IAS) is an uncommon cause of spontaneous hypoglycemia from hyperinsulinemia due to autoantibodies against endogenous insulin (Jian-Ping Chu, 2016). These individuals have no prior exposure to exogenous insulin. We report a case of a 35-year-old African American male, who presented to Vaughn Regional Medical Center in Selma, AL, after he was found to have seizures from hypoglycemia, with a blood sugar of 63 on presentation. He was never diagnosed with diabetes in the past, nor did he have a history of seizure disorder. He continued to be hypoglycemic during the initial period of his hospital stay. His fasting insulin level was 27 mIU/l (normal is less than 25, with presence of insulin autoantibodies (IAA), and a negative workup otherwise. This led us to include IAS as one of our differentials for his hypoglycemia.

Structural investigations of (Mn, Dy) co-doped ZnO nanocrystals using X-ray absorption studies

EXAFS measurements on sol gel derived (Mn, Dy) co-doped ZnO nanocrystals show that oxygen vacancies are created near the Dy sites into ZnO lattice. Thus, oxygen vacancy assisted bound magnetic polarons contribute to the RTFM in the Dy doped samples.

Structural and optical properties of sol–gel derived Cr-doped ZnO diluted magnetic semiconductor nanocrystals: an EXAFS study to relate the local structure

Structural, local structural and optical properties of sol–gel derived Zn_1−xCr_xO (0 ≤ x ≤ 0.06) nanoparticles have been thoroughly studied by several complementary techniques.

Investigations of some aspects of the spray process in a single wire arc plasma spray system using high speed camera

A high speed camera has been used to record and analyze the evolution as well as particle behavior in a single wire arc plasma spray torch. Commercially available systems (spray watch, DPV 2000, etc.) focus onto a small area in the spray jet. They are not designed for tracking a single particle from the torch to the substrate. Using high speed camera, individual particles were tracked and their velocities were measured at various distances from the spray torch. Particle velocity information at different distances from the nozzle of the torch is very important to decide correct substrate position for the good quality of coating. The analysis of the images has revealed the details of the process of arc attachment to wire, melting of the wire, and detachment of the molten mass from the tip. Images of the wire and the arc have been recorded for different wire feed rates, gas flow rates, and torch powers, to determine compatible wire feed rates. High speed imaging of particle trajectories has been used for particle velocity determination using time of flight method. It was observed that the ripple in the power supply of the torch leads to large variation of instantaneous power fed to the torch. This affects the velocity of the spray particles generated at different times within one cycle of the ripple. It is shown that the velocity of a spray particle depends on the instantaneous torch power at the time of its generation. This correlation was established by experimental evidence in this paper. Once the particles leave the plasma jet, their forward speeds were found to be more or less invariant beyond 40 mm up to 500 mm from the nozzle exit.

Update on pharmacological treatment of anxiety disorders: Where is the greatest room for imrpovement?

The ideal anxiolytic drug would be effective in all anxiety disorders, with a rapid onset of action, across all symptom domains and the spectrum of severity, in achieving remission and minimising disability, in preventing relapse, and in treating comorbid depression. Ideally, the drug would be suitable for once-daily dosage, would have minimal adverse effects or cause minimal interference with everyday life, not lead to the development of tolerance, have no discontinuation symptoms, be suitable in physically ill patients and free from interactions, and be safe in overdose.

But there are no ideal anxiolytic drugs. Response rates to initial treatment can be disappointing, it is not possible to reliably predict likelihood of response; a substantial proportion of patients experience unwanted effects; many will relapse despite treatment adherence; comparatively little is known about further management after initial non-response; and discontinuation symptoms can be troublesome.

Hence there is much room for improvement in identifying those patients who are most likely to benefit from treatment; in choosing between drug and psychological treatments; in choosing the right drug for the right patient groups; in optimising medication dosage to achieve maximum effectiveness whilst minimising adverse effects; in combining drug treatments to enhance efficacy; and in treating over the long term to prevent relapse and recurrence.

Actions of vitamin D are mediated by the TLR4 pathway in inflammation-induced colon cancer

Many chronic inflammatory diseases are associated with increased risk of developing cancer. In the colon, strong support for a link between chronic inflammation and cancer extends, in part, from population-based studies of persons with inflammatory bowel disease (IBD). Patients with IBD are at increased risk of developing colorectal cancer (CRC). The general consensus is that IBD results from the combined effects of genetics and environment factors known to affect the immune system. Vitamin D, an important regulator of the immune system, has been linked to IBD. Despite the strong potential reported for 1,25-dihydroxyvitamin D (1,25-OH)2D), its effects on calcium metabolism limits its application. Recently, less active vitamin D metabolites, cholecalciferol and 25-hydroxyvitamin D (25(OH)D), have gained considerable attention as promising agents against IBD-related colon cancer. Yet, their anti-proliferative properties and mechanism of action remain to be better defined. We present several signaling pathways commonly regulated by vitamin D compounds and highlight their regulation on TLR4. The efficacy of 25(OH)D and 1alpha-hydroxyviatmin D5 are evaluated using the azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced IBD-related colon carcinogenesis model. In summary, vitamin D supplementation may provide a cost-effective approach to reduce IBD related colon cancer.

Aggressive angiomyxoma of the jejunum: a rare cause of obscure gastrointestinal bleeding

Obscure gastrointestinal bleeding accounts for nearly 5% of all gastrointestinal haemorrhage and is frequently due to a lesion in the small bowel. We report the case of a male patient with obscure overt gastrointestinal bleed in whom repeated upper gastrointestinal endoscopy, colonoscopy, computed tomography scanning and exploratory laparotomy showed no specific pathology. However, on capsule endoscopy done subsequently, a small polyp in the jejunum was located and resected. Histology revealed an aggressive angiomyxoma. This type of small bowel lesion has not been reported in the literature before.

Protonation and Salting-in Behaviour of Weak Organic Bases in HClO4

Various protonation parameters (p

Replication factor C disengages from proliferating cell nuclear antigen (PCNA) upon sliding clamp formation, and PCNA itself tethers DNA polymerase delta to DNA

Replication factor C (RF-C) and proliferating cell nuclear antigen (PCNA) assemble a complex, called sliding clamp, onto DNA. The clamp in turn loads DNA polymerases (pol) delta and epsilon to form the corresponding holoenzymes, which play an essential role in replication of eukaryotic chromosomal DNA and in several DNA repair pathways. To determine the fate of RF-C after loading of PCNA onto DNA, we tagged the RF-C subunit p37 with a protein kinase A recognition motif, so that the recombinant five-subunit RF-C complex could be 32P-labeled and quantitatively detected in femtomolar amounts. Nonspecific binding of RF-C to DNA was minimized by replacing the p140 subunit with an N-terminally truncated p140 subunit lacking the previously identified nonspecific DNA binding domain. Neither of these modifications impaired the clamp loading activity of the recombinant RF-C. Using gel filtration techniques, we demonstrated that RF-C dissociated from the DNA after clamp loading or pol delta holoenzyme assembly, while PCNA or PCNA.pol delta complex remained bound to DNA. PCNA catalytically loaded onto the template-primer was sufficient by itself to tether pol delta and stimulate DNA replication. The readdition of RF-C to the isolated PCNA.DNA complex did not further stimulate pol delta DNA synthesis. We conclude that pol delta holoenzyme consists of PCNA and pol delta core and that RF-C serves only to load PCNA clamp.

Functional interactions among the subunits of replication factor C potentiate and modulate its ATPase activity

Replication factor C (RF-C), a complex of five subunits, and several subassemblies of RF-C, representing intermediates along the proposed protein assembly pathway (Podust, V. N., and Fanning, E. (1997) J. Biol. Chem. 272, 6303-6310), were expressed in insect cells using baculoviruses encoding individual subunits (p140, p40, p38, p37, and p36). Purified proteins were analyzed for ATPase activity to assess the role of individual subunits in ATP hydrolysis. His-tagged p40 contained low ATPase activity, but tagged p37 and p36 did not. Complexes of p40.p37.p36 bearing a His tag on any subunit displayed DNA-stimulated ATPase activity, in agreement with a recent report (Cai, J., Gibbs, E., Uhlmann, F., Philips, B., Yao, N., O'Donnell, M. , and Hurwitz, J. (1997) J. Biol. Chem. 272, 18974-18981). In contrast, complex p38.p37.p36-his displayed no ATPase, suggesting that p40 is essential for ATPase activity. Although p38 was not required for ATPase activity, the activity of the p40-his.p38.p37. p36 complex was more salt-resistant than that of the p40-his.p37.p36 complex. The p140 subunit further increased the specific ATPase activity of RF-C complex by enhancing its stimulation by DNA. Taken together, the data indicate that all five RF-C subunits constitute ATPase activity, although the contributions of the individual subunits differ. Predicted ATP-binding domains of all five subunits were mutated to assess the importance of multiple ATP-binding sites of RF-C. In each case, the Lys of the conserved P-loop motif was replaced by Glu. The ATP-binding domain of p38 was found to be dispensable for the activity of the five-subunit RF-C in polymerase delta DNA synthesis. In contrast, mutation of the ATP-binding domains in other RF-C subunits impaired RF-C assembly, function, or both.

Purification and preliminary characterization of L-asparaginase from Erwinia aroideae NRRL B-138

L-Asparaginase (L-asparagine amidohydrolase EC 3.5.1.1) from Erwinia aroideae NRRL B-138 has been purified to apparent homogeneity by ammonium sulphate precipitation, chromatography on sulfopropyl-sephadex C-50 and sephadex G-200 with 22% recovery and 567-fold purification. The enzyme obtained from sulfopropyl-sephadex C-50 was unstable and lost activity within a few hours. Addition of glycerol helped in restoring the activity of the enzyme. The enzyme has an apparent molecular mass of approximately 155 kDa and has four subunits of identical molecular mass of approximately 38 kDa. The K(m) for L-asparagine is 2.8 x 10(-3) M. Enzyme shows optimal activity at 45 degrees C and pH 8.2. Energy of activation as determined from Arrhenius plot was 9.1 kcal/mol. Substrate L-asparagine and analogue L-glutamine, D-asparagine and 6 diazo-5-oxo-L-norleucine provide full protection to the enzyme against thermal denaturation.

Synthesis of some pyrazoline and isoxazolin derivatives as possible fungicides

1-Acetyl/aroyl-3-methyl-4-substituted anilido-5-aryl pyrazolines and 3-methyl-4-substituted anilido-5-aryl isoxazolines were conveniently prepared from synthon, 4-aryl-3-substituted anilido but-3-en-2-ones in presence of hydrazine hydrate/hydrazides and hydroxylamine hydrochloride respectively. All the compounds have been assayed against Cephalosporium sacchari and Helminthosporium oryzae and found remarkably active. Two species of aquatic fungi viz. Saprolegnia parasitica and Achlya orion responsible for fish mycoses were tested and also found remarkably active.