BACKGROUND: Rabies is an important zoonotic disease that needs to be eradicated worldwide. It is still prevalent in the Philippines, thus development of a relatively affordable but still accurate and rapid post-mortem detection test for the virus is desired, especially in regional laboratories.
METHODS:The study evaluated the Direct Rapid Immunohistochemical Testing (DRIT) of hippocampal touch impressions of suspected rabid Canis lupus familiaris using monospecific N protein polyclonal antibody developed by the Research Institute for Tropical Medicine (RITM). One hundred sixty (160) acetone-fixed hippocampal touch impressions were subjected DRIT.
RESULTS: One hundred thirteen (70.6%) out of 160 samples tested positive for rabies viral antigen (RVA) and 47 (29.4%) out of 160 samples tested negative for RVA. No false positive and false negative results were obtained. The results agree with the gold standard, dFAT.
CONCLUSION: DRIT was able to detect low to high concentrations of RVA in the hippocampal touch impressions based on the grading distribution. DRIT had 100% sensitivity, specificity and over-all accuracy using monospecific polyclonal antibodies, which suggests its use as a more affordable alternative to the gold standard dFAT.

Animal ; Antigens, Viral ; Dogs ; Hippocampus ; Rabies ; Rabies Virus ; Sensitivity And Specificity ; Touch ; Tropical Medicine ; Immunohistochemistry

There is a scarcity of experimental studies on peripheral nerve regeneration using placental extract (PE). This study aimed to investigate the effects of topical PE application on recovery after crush injury to the rat facial nerve using functional, electrophysiological, and morphological evaluations. The viability of the RSC96 Schwann cells treated with PE (0.5~4 mg/ml) increased significantly. Immunoblot test revealed that PE application enhanced the migration of RSC96 cells. Quantitative polymerase chain reaction demonstrated that PE increased the expression of neurotropic genes. The recovery from vibrissa fibrillation in the PE-treated group was superior to that in the control group. The threshold of action potential was also significantly lower in the PE group. Histopathological examination showed that crushed facial nerves treated with PE exhibited larger axons. The surrounding myelin sheaths were more distinct and thicker in the PE-treated group. Hence, PE may be considered a topical therapeutic agent for treating traumatic facial nerve paralysis.

Purpose: Parkinson disease (PD) is a progressive neurodegenerative disorder in which dopaminergic (DAergic) systems are destroyed (particularly in the nigrostriatal system), causing both motor and nonmotor symptoms. Hippocampal neuroplasticity is altered in PD animal models, resulting in nonmotor dysfunctions. However, little is known about the precise mechanism underlying the hippocampal dysfunctions in PD. Methods: Striatal 6-hydroxydopamine (6-OHDA) infusions were performed unilaterally in adult Sprague Dawley rats. Both motor and nonmotor symptoms alongside the expression of tyrosine hydroxylase (TH) in the substantia nigra and striatum were confirmed in 6-OHDA-lesioned rats. The neuronal architecture in the hippocampus was analyzed by Golgi staining. Results: During the 7–8 weeks after infusion, the 6-OHDA-lesioned rats exhibited motor and nonmotor dysfunctions (especially anxiety/depression-like behaviors). Rats with unilateral 6-OHDA infusion displayed reduced TH+ immunoreactivity in the ipsilateral nigrostriatal pathway of the brain. Golgi staining revealed that striatal 6-OHDA infusion significantly decreased the dendritic complexity (i.e., number of crossing dendrites, total dendritic length, and branch points) in the ipsilateral hippocampal conus ammonis 1 (CA1) apical/basal and dentate gyrus (DG) subregions. Additionally, the dendritic spine density and morphology were significantly altered in the CA1 apical/basal and DG subregions following striatal 6-OHDA infusion. However, alteration of microglial and astrocytic distributions did not occur in the hippocampus following striatal 6-OHDA infusion. Conclusions The present study provides anatomical evidence that the structural plasticity in the hippocampus is altered in the late phase following striatal 6-OHDA infusion in rats, possibly as a result of the prolonged suppression of the DAergic system, and independent of neuroinflammation.