Two prophenoloxidases are important for the survival of Vibrio harveyi challenged shrimp Penaeus monodon

Phenoloxidase (PO) plays an important role in arthropod melanization. Previously, a prophenoloxidase (PmproPO1) gene was cloned and characterized from the hemocytes of the black tiger shrimp, Penaeus monodon. In the present study, we report a novel proPO gene (PmproPO2) belonging to the proPO family identified from the P. monodon EST database (http://pmonodon.biotec.or.th). The full-length sequence of PmproPO2 consists of 2513bp encoding a predicted 689 amino acid residues with a calculated molecular mass and pI of 79.21kDa and 6.69, respectively. It is predicted to possess all the expected features of proPO members, including two putative tyrosinase copper-binding motifs with six histidine residues and a thiol ester-like motif, sharing 67% amino acid sequence identity with PmproPO1. Tissue distribution analyses revealed that the two proPO genes are primarily expressed in the hemocyte. Gene silencing of either PmproPO1 or PmproPO2 or both by RNA interference (RNAi) resulted in a significant decrease in the respective endogenous proPO mRNA level in hemocytes and a reduction of total PO enzyme activity by 75, 73 and 88%, respectively. Experimental infection of P. monodon with the pathogenic bacterium, Vibrio harveyi, revealed that PmproPO silenced shrimps were more susceptible to bacterial infection than the control GFP injected shrimps, and suggesting that the two proPOs are important components in the shrimp immune defense.     

Furious and paralytic rabies of canine origin: Neuroimaging with virological and cytokine studies

Furious and paralytic rabies differ in clinical manifestations and survival periods. The authors studied magnetic resonance imaging (MRI) and cytokine and virus distribution in rabies-infected dogs of both clinical types. MRI examination of the brain and upper spinal cord was performed in two furious and two paralytic dogs during the early clinical stage. Rabies viral nucleoprotein RNA and 18 cytokine mRNAs at 12 different brain regions were studied. Rabies viral RNA was examined in four furious and four paralytic dogs during the early stage, and in one each during the late stage. Cytokine mRNAs were examined in two furious and two paralytic dogs during the early stage and in one each during the late stage. Larger quantities of rabies viral RNA were found in the brains of furious than in paralytic dogs. Interleukin-1beta and interferon-gamma mRNAs were found exclusively in the brains of paralytic dogs during the early stage. Abnormal hypersignal T2 changes were found at hippocampus, hypothalamus, brainstem, and spinal cord of paralytic dogs. More widespread changes of less intensity were seen in furious dog brains. During the late stage of infection, brains from furious and paralytic rabid dogs were similarly infected and there were less detectable cytokine mRNAs. These results suggest that the early stage of furious dog rabies is characterized by a moderate inflammation (as indicated by MRI lesions and brain cytokine detection) and a severe virus neuroinvasiveness. Paralytic rabies is characterized by delayed viral neuroinvasion and a more intense inflammation than furious rabies. Dogs may be a good model for study of the host inflammatory responses that may modulate rabies virus neuroinvasiveness.     

Tabernaemontana divaricata extract inhibits neuronal acetylcholinesterase activity in rats

The current pharmacotherapy for Alzheimer's disease (AD) is the use of acetylcholinesterase inhibitors (AChE-Is). A previous in vitro study showed that Tabernaemontana divaricata extract (TDE) can inhibit AChE activity. However, neither the AChE inhibitory effects nor the effect on neuronal activity of TDE has been investigated in vivo. To determine those effects of TDE in animal models, the Ellman's colorimetric method was implemented to investigate the cortical and circulating cholinesterase (ChE) activity, and Fos expression was used to determine the neuronal activity in the cerebral cortex, following acute administration of TDE with various doses (250, 500 and 1000 mg/kg) and at different time points. All doses of TDE 2 h after a single administration significantly inhibited cortical AChE activity and enhanced neuronal activity in the cerebral cortex. The enhancement of Fos expression and AChE inhibitory effects in the cerebral cortex among the three TDE-treated groups was not significantly different. A 2 h interval following all doses of TDE administration had no effect on circulating ChE activity. However, TDE significantly inhibited circulating AChE 10, 30 and 60 min after administration. Our findings suggest that TDE is a reversible AChE-I and could be beneficial as a novel therapeutic agent for AD.     

Ganoderma lucidum: a cause of pseudoparasitosis

We report a pseudoparasitosis case due to Ganoderma lucidum, (lingzhi or reishi mushroom); we believe this to be a first reported case in Thailand. A 49-year-old male patient with non-Hodgkins lymphoma presented with chronic watery diarrhea. He had a history of consumption of powdered lingzhi extract as a dietary supplement and herbal medicine. Stool examination demonstrated many spores of G. lucidum, which must be differentiated from intestinal helminth ova and coccidia. After discontinuation of mushroom spores ingestion, the diarrheal symptoms improved and fecal examination subsequently showed no Ganoderma spores. Many artifacts in the stool may be confused with parasites. Differentiation of parasites from artifacts depends on characterization of the size, shape, structure, and reactivity with common stains.     

Efficacy and safety of switching to bictegravir,emtricitabine, and tenofovir alafenamide in virologically suppressed Asian adults living with HIV: A pooled analysis from three international phase III randomized trials

Objectives

Data on switching to bictegravir, emtricitabine, and tenofovir alafenamide (B/F/TAF) in virologically suppressed Asian people living with HIV are limited. We performed a pooled analysis of virologically suppressed Asian participants from three international phase III trials to evaluate the efficacy and safety of switching to B/F/TAF.

Methods

Virologically suppressed people living with HIV were randomized to switch to B/F/TAF or to stay on baseline regimens. The primary endpoint was the proportion of participants with plasma HIV-1 RNA ≥50 copies/ml at week 48. We analysed the incidence of adverse events (AEs), laboratory abnormalities, and changes in relevant tolerability parameters through 48 weeks.

Results

Overall, 136 Asian participants were included. The proportions of participants with plasma HIV-1 RNA ≥50 copies/ml at week 48 were low in both arms (0% for B/F/TAF vs 1.4% for those who stayed on baseline regimens). Those who switched to B/F/TAF had virological suppression rates similar to those who stayed on baseline regimens (100% vs 95.9%, p = 0.2485), with no treatment-emergent resistance. Drug-related AEs occurred in three participants in each arm; none were serious. No participants discontinued the study drug because of AEs, and no deaths were observed. No significant differences were observed between the arms in the median changes in estimated glomerular filtration rate, body weight, and most lipid parameters. Switching from tenofovir disoproxil fumarate-containing regimens to B/F/TAF resulted in a significant decrease in tubular proteinuria compared with those who stayed on baseline regimens (p < 0.01).

Conclusions

Virologically suppressed Asian people living with HIV who switched to B/F/TAF maintained 100% virological suppression at week 48, with no treatment-emergent drug resistance and safety profiles comparable to those seen in people who stayed on baseline regimens.

Clinical Trial Number

ClinicalTrials.gov (NCT02603120, NCT02652624, and NCT02603107).     

A randomized trial of combination hepatitis B therapy in HIV/HBV coinfected antiretroviral naïve individuals in Thailand

Coinfection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) is associated with considerable liver disease morbidity and mortality. Emerging HIV epidemics in areas of high HBV endemicity such as Asia are expanding the population with HIV/HBV coinfection. Limited randomized trial data exist to support current guidelines for HBV combination therapy in HIV/HBV coinfection. The objective of this prospective randomized clinical trial was to compare the strategy of HBV monotherapy with lamivudine (LAM) or tenofovir disoproxil fumarate (TDF) versus HBV combination therapy with LAM/TDF in antiretroviral-na?ve HIV/HBV-coinfected subjects in Thailand. Thirty-six HIV/HBV-coinfected subjects initiating highly active antiretroviral therapy (HAART) were randomized to either LAM (arm 1), TDF (arm 2), or LAM/TDF (arm 3) as HBV-active drugs within HAART. At week 48, time-weighted area under the curve analysis revealed that the median HBV DNA reduction from baseline was 4.07 log(10) c/mL in arm 1, 4.57 log(10) c/mL in arm 2, and 4.73 log(10) c/mL in arm 3 (P = 0.70). HBV DNA suppressed to <3 log(10) c/mL in 46% in arm 1, 92% in arm 2, and 91% in arm 3 (P = 0.013, intent-to-treat analysis). HBV-resistant changes were detected in two subjects, both in arm 1. Hepatitis B e antigen (HBeAg) loss was observed in 33% of HBeAg-positive subjects, and 8% experienced hepatitis B surface antigen loss. Hepatic flare was observed in 25% of subjects. CONCLUSION: LAM monotherapy resulted in a greater proportion of subjects with HBV DNA >3 log(10) c/mL at week 48 and in early resistance development. This study confirms current treatment guidelines that recommend a TDF-based regimen as the treatment of choice for HIV/HBV coinfection, but does not demonstrate any advantage of HBV combination therapy in this short-term setting.