Medicinal and ethnoveterinary remedies of hunters in Trinidad

BACKGROUND: Ethnomedicines are used by hunters for themselves and their hunting dogs in Trinidad. Plants are used for snakebites, scorpion stings, for injuries and mange of dogs and to facilitate hunting success. RESULTS: Plants used include Piper hispidum, Pithecelobium unguis-cati, Bauhinia excisa, Bauhinia cumanensis, Cecropia peltata, Aframomum melegueta, Aristolochia rugosa, Aristolochia trilobata, Jatropha curcas, Jatropha gossypifolia, Nicotiana tabacum, Vernonia scorpioides, Petiveria alliacea, Renealmia alpinia, Justicia secunda, Phyllanthus urinaria,Phyllanthus niruri,Momordica charantia, Xiphidium caeruleum, Ottonia ovata, Lepianthes peltata, Capsicum frutescens, Costus scaber, Dendropanax arboreus, Siparuma guianensis, Syngonium podophyllum, Monstera dubia, Solanum species, Eclipta prostrata, Spiranthes acaulis, Croton gossypifolius, Barleria lupulina, Cola nitida, Acrocomia ierensis (tentative ID). CONCLUSION: Plant use is based on odour, and plant morphological characteristics and is embedded in a complex cultural context based on indigenous Amerindian beliefs. It is suggested that the medicinal plants exerted a physiological action on the hunter or his dog. Some of the plants mentioned contain chemicals that may explain the ethnomedicinal and ethnoveterinary use. For instance some of the plants influence the immune system or are effective against internal and external parasites. Plant baths may contribute to the health and well being of the hunting dogs

Brainstem blood brain barrier disruption using focused ultrasound: A demonstration of feasibility and enhanced doxorubicin delivery

Magnetic Resonance Image-guided Focused Ultrasound (MRgFUS) has been used to achieve transient blood brain barrier (BBB) opening without tissue injury. Delivery of a targeted ultrasonic wave causes an interaction between administered microbubbles and the capillary bed resulting in enhanced vessel permeability. The use of MRgFUS in the brainstem has not previously been shown but could provide value in the treatment of tumours such as Diffuse Intrinsic Pontine Glioma (DIPG) where the intact BBB has contributed to the limited success of chemotherapy. Our primary objective was to determine whether the use of MRgFUS in this eloquent brain region could be performed without histological injury and functional deficits. Our secondary objective was to select an effective chemotherapeutic against patient derived DIPG cell lines and demonstrate enhanced brainstem delivery when combined with MRgFUS in vivo. Female Sprague Dawley rats were randomised to one of four groups: 1) Microbubble administration but no MRgFUS treatment; 2) MRgFUS only; 3) MRgFUS + microbubbles; and 4) MRgFUS + microbubbles + cisplatin. Physiological assessment was performed by monitoring of heart and respiratory rates. Motor function and co-ordination were evaluated by Rotarod and grip strength testing. Histological analysis for haemorrhage (H & E), neuronal nuclei (NeuN) and apoptosis (cleaved Caspase-3) was also performed. A drug screen of eight chemotherapy agents was conducted in three patient-derived DIPG cell lines (SU-DIPG IV, SU-DIPG XIII and SU-DIPG XVII). Doxorubicin was identified as an effective agent. NOD/SCID/GAMMA (NSG) mice were subsequently administered with 5 mg/kg of intravenous doxorubicin at the time of one of the following: 1) Microbubbles but no MRgFUS; 2) MRgFUS only; 3) MRgFUS + microbubbles and 4) no intervention. Brain specimens were extracted at 2 h and doxorubicin quantification was conducted using liquid chromatography mass spectrometry (LC/MS). BBB opening was confirmed by contrast enhancement on T1-weighted MR imaging and positive Evans blue staining of the brainstem. Normal cardiorespiratory parameters were preserved. Grip strength and Rotarod testing demonstrating no decline in performance across all groups. Histological analysis showed no evidence of haemorrhage, neuronal loss or increased apoptosis. Doxorubicin demonstrated cytotoxicity against all three cell lines and is known to have poor BBB permeability. Quantities measured in the brainstem of NSG mice were highest in the group receiving MRgFUS and microbubbles (431.5 ng/g). This was significantly higher than in mice who received no intervention (7.6 ng/g). Our data demonstrates both the preservation of histological and functional integrity of the brainstem following MRgFUS for BBB opening and the ability to significantly enhance drug delivery to the region, giving promise to the treatment of brainstem-specific conditions

Selective Neuro-oncological Therapies Using Focused Ultrasound to Disrupt the Blood-brain Barrier

Ultrasound in clinical medicine is most commonly associated with imaging, but can be harnessed to yield an array of bioeffects. Of particular interest in neuro-oncology is the interaction of ultrasound with pre-formed ultrasound contrast agents, the combination of which can be used to increase the permeability of the cerebrovasculature in a reversible manner [blood-brain barrier (BBB) disruption]. Many promising therapeutic agents have in vitro efficacy but fail in vivo due to their inability to accumulate to any significant degree in the central nervous system (CNS). While primary brain tumours alone do not impose an enormous healthcare burden compared with many other cancers, as many as 40% of all cancer patients will eventually develop brain metastasis, making the potential impact of drug delivery with ultrasound significantly larger. We focused particularly on therapeutic agents that, once in the brain, selectively targeted malignant cells, as existing therapies cause much morbidity in their wake secondary to collateral neuronal injury. We investigated the effects of BBB disruption on boron neutron capture therapy with the delivery agent boronophenylalanine. BBB disruption increased the absolute boron concentration, important for tumour killing, by almost 150%, and improved the ratio between normal brain and tumour, minimizing radiation to healthy cells. It also increased the uptake in infiltrating cells, particularly important for tumours like glioblastoma. We then demonstrated that an even more selective agent - engineered, targeted immune cells - could be delivered to a brain tumour in a viable state. Furthermore, we demonstrated improved survival in a brain metastasis model of HER2 amplified breast cancer. Both of these targeted therapies have been investigated in early clinical trials, and with the mounting evidence for the safety of BBB disruption with ultrasound, there exists real potential to translate these promising therapies into the clinical realm and offer new treatments to patients with little hope for a cure.Ph.D.2016-09-22 00:00:0

Characterization of absolute extensors for one-dimension spaces in terms of extenders between function spaces

This research paper was completed and submitted at Nipissing University, and is made freely accessible through the University of Toronto’s TSpace repositor