Inter-simple sequence repeat (ISSR) polymorphism-based analysis of diversity in the freshwater turtle genus Pangshura

Assessment of genetic variability among the freshwater turtles is critical to the development of effective conservation strategies. In the present study, analysis of phenetic relationship of the genus Pangshura was studied using inter simple sequence repeat (ISSR) markers to see the concordance of currently available morphological data with genetic data along with spatial pattern of distribution. Ten microsatellite-based primers amplified 156 ISSR markers among 36 individuals belonging to four turtle species Pangshura sylhetensis, Pangshura tecta, Pangshura simithii and Pangshura tentoria, collected from certain localities of Assam, West Bengal and Uttar Pradesh of India. Estimations of Nei’s genetic diversity (h), Shannon’s Index (I) and Total genetic diversity (Ht) reveal the existence of greater genetic diversity in P. tentoria and P. sylhetensis than in the other two species. However, low values of gene flow (Nm) and of within sample diversity (Hs) indicate prevalence of inbreeding in these species groups. The coefficients of differentiation (GST) values divulge that divergence started in the Pangshura species. Projections on the principal components analysis (PCA) plot reflect the distinct genetic identity of these four species. The consensus Neighbour Joining dendogram depicts P. sylhetensis, P. tecta, and P. tentoria as genetically closer to each other than to P. smithii.Keywords: Differentiation, genetic diversity, inter simple sequence repeat (ISSR), Pangshura, turtleAfrican Journal of Biotechnology Vol. 12(3), pp. 238-24

Evaluation of Some Heavy Metals in Aerial Parts of Wild Rice Plant in Kaduna State, Nigeria

This study was designed to evaluate the level of Cd, Co, Fe and Zn in the aerial/upper parts of wild rice plant in three locations (Gure, Kagoro, and Kaduna) of Kaduna state. HNO3-H2O2 was used to digest the plant samples and analyzed using AA320N model Atomic absorption spectrophotometer. The results obtained revealed that, the concentration(mg kg-1 dry weight basis) of the heavy metals analyzed in the upper parts of wild rice plant were 0.242, 0.028, 2.947 and 19.145 for Cd, Co Fe, and Zn respectively. Also in the grain, the concentration of metals was found to be 0.223, 0.023, 2.003 and 19.050 for Cd, Co, Fe, and Zn respectively. The ANOVA result showed that the concentration of Cd, Co and Fe were not significantly different within the plant parts while that of Zn was different at 95% confidence limit. The concentration of Zn, Fe and Co in the wild rice plant and grain were within the limits obtained in most world crops and vegetables and WHO/FAO reference standards. Although, the concentration of Cd in grain was a little higher than the recommended limit of WHO/FAO reference standard. The dietary implication of the elements, suggests that the consumption of the wild rice plant/grain analyzed may not cause much health hazard to grazing animals and human beings.Keywords: Aerial part, Grain, Heavy metals, Wild ric

Persistent Hiccups After Cervical Epidural Steroid Injection.

BACKGROUND Hiccup is a rare complication after a cervical epidural steroid injection used in the treatment of chronic pain. A few studies have reported on the physiological and pharmacological aspects of hiccups after epidural steroid injection and there have been some case reports published. Our presented case report provides insight into the side effect of hiccups that can occur in association with cervical epidural analgesia, and will help inform anesthesiologist about this unpleasant complication. CASE REPORT We present a rare case of persistent hiccups after a cervical epidural steroid injection in a 60-year-old male patient with chronic pain due to disc protrusion in C3-C7. CONCLUSIONS Persistent hiccups after epidural injection is a serious complication. As the exact mechanism of hiccups is not yet known, regardless the level of epidural or the mixture of drugs used, and the incident of hiccups after epidural injection is not well-reported, we think that the etiology and the incident rate must be further evaluated

Fuzzy Fibers: Uncertainty in dMRI Tractography

Fiber tracking based on diffusion weighted Magnetic Resonance Imaging (dMRI) allows for noninvasive reconstruction of fiber bundles in the human brain. In this chapter, we discuss sources of error and uncertainty in this technique, and review strategies that afford a more reliable interpretation of the results. This includes methods for computing and rendering probabilistic tractograms, which estimate precision in the face of measurement noise and artifacts. However, we also address aspects that have received less attention so far, such as model selection, partial voluming, and the impact of parameters, both in preprocessing and in fiber tracking itself. We conclude by giving impulses for future research

Reducing Versatile Bat Wing Conformations to a 1-DoF Machine

Recent works have shown success in mimicking the flapping flight of bats on the robotic platform Bat Bot (B2). This robot has only five actuators but retains the ability to flap and fold-unfold its wings in flight. However, this bat-like robot has been unable to perform folding-unfolding of its wings within the period of a wingbeat cycle, about 100 ms. The DC motors operating the spindle mechanisms cannot attain this folding speed. Biological bats rely on this periodic folding of their wings during the upstroke of the wingbeat cycle. It reduces the moment of inertia of the wings and limits the negative lift generated during the upstroke. Thus, we consider it important to achieve wing folding during the upstroke. A mechanism was designed to couple the flapping cycle to the folding cycle of the robot. We then use biological data to further optimize the mechanism such that the kinematic synergies of the robot best match those of a biological bat. This ensures that folding is performed at the correct point in the wingbeat cycle

Aquaporin-4 and brain edema.

Aquaporin-4 (AQP4) is a water-channel protein expressed strongly in the brain, predominantly in astrocyte foot processes at the borders between the brain parenchyma and major fluid compartments, including cerebrospinal fluid (CSF) and blood. This distribution suggests that AQP4 controls water fluxes into and out of the brain parenchyma. Experiments using AQP4-null mice provide strong evidence for AQP4 involvement in cerebral water balance. AQP4-null mice are protected from cellular (cytotoxic) brain edema produced by water intoxication, brain ischemia, or meningitis. However, AQP4 deletion aggravates vasogenic (fluid leak) brain edema produced by tumor, cortical freeze, intraparenchymal fluid infusion, or brain abscess. In cytotoxic edema, AQP4 deletion slows the rate of water entry into brain, whereas in vasogenic edema, AQP4 deletion reduces the rate of water outflow from brain parenchyma. AQP4 deletion also worsens obstructive hydrocephalus. Recently, AQP4 was also found to play a major role in processes unrelated to brain edema, including astrocyte migration and neuronal excitability. These findings suggest that modulation of AQP4 expression or function may be beneficial in several cerebral disorders, including hyponatremic brain edema, hydrocephalus, stroke, tumor, infection, epilepsy, and traumatic brain injury

Room temperature plasmon laser by total internal reflection

Plasmon lasers create and sustain intense and coherent optical fields below light's diffraction limit with the unique ability to drastically enhance light-matter interactions bringing fundamentally new capabilities to bio-sensing, data storage, photolithography and optical communications. However, these important applications require room temperature operation, which remains a major hurdle. Here, we report a room temperature semiconductor plasmon laser with both strong cavity feedback and optical confinement to 1/20th of the wavelength. The strong feedback arises from total internal reflection of surface plasmons, while the confinement enhances the spontaneous emission rate by up to 20 times.Comment: 8 Page, 2 Figure

Revisiting protein aggregation as pathogenic in sporadic Parkinson and Alzheimer diseases.

The gold standard for a definitive diagnosis of Parkinson disease (PD) is the pathologic finding of aggregated α-synuclein into Lewy bodies and for Alzheimer disease (AD) aggregated amyloid into plaques and hyperphosphorylated tau into tangles. Implicit in this clinicopathologic-based nosology is the assumption that pathologic protein aggregation at autopsy reflects pathogenesis at disease onset. While these aggregates may in exceptional cases be on a causal pathway in humans (e.g., aggregated α-synuclein in SNCA gene multiplication or aggregated β-amyloid in APP mutations), their near universality at postmortem in sporadic PD and AD suggests they may alternatively represent common outcomes from upstream mechanisms or compensatory responses to cellular stress in order to delay cell death. These 3 conceptual frameworks of protein aggregation (pathogenic, epiphenomenon, protective) are difficult to resolve because of the inability to probe brain tissue in real time. Whereas animal models, in which neither PD nor AD occur in natural states, consistently support a pathogenic role of protein aggregation, indirect evidence from human studies does not. We hypothesize that (1) current biomarkers of protein aggregates may be relevant to common pathology but not to subgroup pathogenesis and (2) disease-modifying treatments targeting oligomers or fibrils might be futile or deleterious because these proteins are epiphenomena or protective in the human brain under molecular stress. Future precision medicine efforts for molecular targeting of neurodegenerative diseases may require analyses not anchored on current clinicopathologic criteria but instead on biological signals generated from large deeply phenotyped aging populations or from smaller but well-defined genetic-molecular cohorts

Polymerase Chain Reaction for Prognosis Assessment and Monitoring of the Epstein-Barr Virus-Associated Hodgkin’s Lymphoma

The review provides the analysis of 34 papers on polymerase chain reaction (PCR) as a method of the Epstein-Barr virus (EBV) DNA detection in biological material of patients with EBV-associated cancer diseases including Hodgkin’s lymphoma (HL). A comparative analysis of different methods of EBV DNA detection in biological material is presented. EBV is associated with HL in 20 to 100 % of cases depending on a geographic region and HIV status. EBV-associated HLs are characterized by latency type II. EBV is found in all the atypical cells and can be detected in blood of EBV-associated HL patients by means of the PCR method. The review includes the results of studies on EBV detection using the PCR method compared to in situ methods of hybridization and immunohistochemistry in various EBV-associated cancer diseases including HL. The obtained data indicate that PCR can be used for quantitative determination of EBV DNA in blood plasma of HL patients for therapeutic efficacy monitoring and prognosis assessment of disease and relapses. Quantitative determination of EBV DNA in blood plasma of HL patients using the real time PCR method is a promising technique. Its further practical application requires standardization of the method, larger trials, and comparison to positron emission tomography

Sociobiological Control of Plasmid copy number

Background:
All known mechanisms and genes responsible for the regulation of plasmid replication lie with the plasmid rather than the chromosome. It is possible therefore that there can be copy-up mutants. Copy-up mutants will have within host selective advantage. This would eventually result into instability of bacteria-plasmid association. In spite of this possibility low copy number plasmids appear to exist stably in host populations. We examined this paradox using a computer simulation model.

Model:
Our multilevel selection model assumes a wild type with tightly regulated replication to ensure low copy number. A mutant with slightly relaxed replication regulation can act as a “cheater” or “selfish” plasmid and can enjoy a greater within-host-fitness. However the host of a cheater plasmid has to pay a greater cost. As a result, in host level competition, host cell with low copy number plasmid has a greater fitness. Furthermore, another mutant that has lost the genes required for conjugation was introduced in the model. The non-conjugal mutant was assumed to undergo conjugal transfer in the presence of another conjugal plasmid in the host cell.

Results:
The simulatons showed that if the cost of carrying a plasmid was low, the copy-up mutant could drive the wild type to extinction or very low frequencies. Consequently, another mutant with a higher copy number could invade the first invader. This process could result into an increasing copy number. However above a certain copy number within-host selection was overcompensated by host level selection leading to a rock-paper-scissor (RPS) like situation. The RPS situation allowed the coexistence of high and low copy number plasmids. The non-conjugal “hypercheaters” could further arrest the copy numbers to a substantially lower level.

Conclusions:
These sociobiological interactions might explain the stability of copy numbers better than molecular mechanisms of replication regulation alone