Otter Research Articles

Lutetium Texaphyrin-Celecoxib Conjugate as a Potential Immuno-Photodynamic Therapy Agent.

Immuno-photodynamic therapy (IPDT) has emerged as a new modality for cancer treatment. Novel photosensitizers can help achieve the promise inherent in IPDT, namely, the complete eradication of a tumor without recurrence. We report here a small molecule photosensitizer conjugate, LuCXB. This IPDT agent integrates a celecoxib (cyclooxygenase-2 inhibitor) moiety with a near-infrared absorbing lutetium texaphyrin photocatalytic core. In aqueous environments, the two components of LuCXB are self-associated through inferred donor-acceptor interactions. A consequence of this intramolecular association is that upon photoirradiation with 730 nm light, LuCXB produces superoxide radicals (O2-•) via a type I photodynamic pathway; this provides a first line of defense against the tumor while promoting IPDT. For in vivo therapeutic applications, we prepared a CD133-targeting, aptamer-functionalized exosome-based nanophotosensitizer (Ex-apt@LuCXB) designed to target cancer stem cells. Ex-apt@LuCXB was found to display good photosensitivity, acceptable biocompatibility, and robust tumor targetability. Under conditions of photoirradiation, Ex-apt@LuCXB acts to amplify IPDT while exerting a significant antitumor effect in both liver and breast cancer mouse models. The observed therapeutic effects are attributed to a synergistic mechanism that combines antiangiogenesis and photoinduced cancer immunotherapy.

Lutetium texaphyrin: A photocatalyst that triggers pyroptosis via biomolecular photoredox catalysis

Photon-controlled pyroptosis activation (PhotoPyro) is a promising technique for cancer immunotherapy due to its noninvasive nature, precise control, and ease of operation. Here, we report that biomolecular photoredox catalysis in cells might be an important mechanism underlying PhotoPyro. Our findings reveal that the photocatalyst lutetium texaphyrin (MLu) facilitates rapid and direct photoredox oxidation of nicotinamide adenine dinucleotide, nicotinamide adenine dinucleotide phosphate, and various amino acids, thereby triggering pyroptosis through the caspase 3/GSDME pathway. This mechanism is distinct from the well-established role of MLu as a photodynamic therapy sensitizer in cells. Two analogs of MLu, bearing different coordinated central metal cations, were also explored as controls. The first control, gadolinium texaphyrin (MGd), is a weak photocatalyst but generates reactive oxygen species (ROS) efficiently. The second control, manganese texaphyrin (MMn), is ineffective as both a photocatalyst and a ROS generator. Neither MGd nor MMn was found to trigger pyroptosis under the conditions where MLu was active. Even in the presence of a ROS scavenger, treating MDA-MB-231 cells with MLu at concentrations as low as 50 nM still allows for pyroptosis photo-activation. The present findings highlight how biomolecular photoredox catalysis could contribute to pyroptosis activation by mechanisms largely independent of ROS.

Effect of Motexafin lutetium-mediated ultrasound-guided red laser photodynamic therapy on endothelial dysfunction using a new automatic ultrasound image processing software

Abstract Background As is well recognized, the majority of atherosclerosis start with an inflammatory process, resulting in endothelial dysfunction. Purpose In this study, we developed an experimental photosensitizer Motexafin lutetium (Lu-Tex)-mediated photodynamic therapy system, and investigated its effectiveness on endothelial dysfunction improvement in an animal model of balloon dilation injury, using a new automatic ultrasound image processing software. Methods Briefly, Golden Syrian hamsters' femoral artery underwent balloon dilatation injury. After four weeks, femoral arteries of the treatment group at the lesion region, treated using Motexafin lutetium - mediated fiber optic catheter-based red low level laser (742 nm, 150 J/cm2) photodynamic therapy. In order to evaluate endothelial-dependent relaxation, acetylcholine-mediated dilation (AMD) was measured during the infusion of acetylcholine at a rate of 0.5 μg/kg/min and endothelial independent relaxation was evaluated by measuring nitroglycerin mediated dilation (NMD) during the infusion of nitroglycerin at a rate of 5μg/kg/min. For off-line analysis, a computerized analysis method for evaluating instantaneous changes in the wall of the hamster femoral artery was used. For automatic measurement of the mean wall thickness and the lumen diameter from longitudinal B-mode ultrasound images, two algorithms, i.e., maximum gradient and dynamic programming were composed and implemented. Reference points and cost function were based on dynamic programming and maximum gradient, respectively. Results Results from computerized B-mode ultrasound image processing software showed significant differences in AMD between the treated and the non-treated hamsters (p<0.05), whereas there were no significant differences in NMD between the treatment and normal groups (p>0.05). Conclusion Cytotoxic and anti-inflammatory effect of Motexafin lutetium, induced by red laser photodynamic therapy accompanied by photobiomodulation effect of red laser, can cause to reduce the immune cells in intimal layer and improve the endothelial dysfunction via increasing the endothelial nitric oxide synthase function. Furthermore, it is concluded that the new automatic method enables accurate and repeated evaluation of the endothelial dysfunction using photodynamic therapy in this model. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Mehrad Research Lab

Photodynamic therapy for prostate cancer - A narrative review.

This article is a review of approaches to treatment of low and high-grade prostate cancer including a discussion of active treatment vs. active surveillance for patients with low-grade prostate cancer. In particular, we will review PDT as an option for active treatment of low-grade prostate cancer considered in light of recent clinical trials. The mechanism and clinical methods of PDT application and the key points from clinical trials using PDT for prostate cancer with the photosensitizers m-tetrahydroxyphenyl chloride, protoporphyrin IX, motexafin lutetium, padoporfin, and padeliporfin between the years 2002 and 2017 are reviewed. Recently developed methodologies for photodynamic prostate cancer treatment that are in the experimental stage, photodynamic diagnosis, fluorescence guided resection, and PSMA-targeted PDT will also be discussed.

The first record of a wild hypopigmented oriental small-clawed otter (Aonyx cinereus)

Hypopigmentation, whose most common forms include albinism and leucism, results in atypical coloration and occurs throughout the animal kingdom. During camera trapping in Bukit Barisan Selatan National Park, Sumatra, we documented the first record of hypopigmentation in oriental small-clawed otters (Aonyx cinereus). Hypopigmentation is rarely documented in the literature, and this appears to be the second record for any otter species.

First record of Otter Civet Cynogale bennettii (Mammalia: Carnivora: Viverridae) kept as a pet in Indonesia, representing a possible new threat to the species

-

Photosensitizers in prostate cancer therapy.

The search for new therapeutics for the treatment of prostate cancer is ongoing with a focus on the balance between the harms and benefits of treatment. New therapies are being constantly developed to offer treatments similar to radical therapies, with limited side effects. Photodynamic therapy (PDT) is a promising strategy in delivering focal treatment in primary as well as post radiotherapy prostate cancer. PDT involves activation of a photosensitizer (PS) by appropriate wavelength of light, generating transient levels of reactive oxygen species (ROS). Several photosensitizers have been developed with a focus on treating prostate cancer like mTHPC, motexafin lutetium, padoporfin and so on. This article will review newly developed photosensitizers under clinical trials for the treatment of prostate cancer, along with the potential advantages and disadvantages in delivering focal therapy.

A novel lutetium(III) acetate phthalocyanine directly substituted with N,N’-dimethylaminophenyl groups via C[formula omitted]C bonds and its water-soluble derivative for photodynamic therapy

In this study, the novel 4-(N,N′-dimethylamino)phenyl substituted lutetium(III) acetate phthalocyanine (2) and its quaternized derivative (3) were synthesized via a Suzuki-Miyaura coupling reaction between tetrakis(iodo) lutetium(III)acetate phthalocyanine (1) and 4-(N,N-dimethylamino)phenylboronic acid, and subsequent quaternization using dimethyl sulfate, respectively. The obtained phthalocyanine 3 exhibited excellent solubility in water which is important for photodynamic therapy applications. Photophysical properties such as fluorescence quantum yield and fluorescence lifetime, and photochemical properties such as singlet oxygen generation and photostability were investigated to determine their suitability for photodynamic therapy. The lutetium(III) phthalocyanines, especially quaternized derivative 3, showed promising properties as potential photosensitizers for the treatment of cancer, producing higher singlet oxygen (ΦΔ=0.59) than motexafin lutetium (ΦΔ=0.31) which is a clinically used lutetium texaphyrin photosensitizer.

Otters Love to Play by Jonathan London (review)

Otters Love to Play by Jonathan London (review)

Estimating catches with automatic identification system (AIS) data: a case study of single otter trawl in Zhoushan fishing ground, China

The sailing tracks of single otter trawl vessels were simulated using cubic hermite spline (cHs) interpolation method based on the automatic identification system (AIS) data of 6 sampled vessels that were fishing in the Zhoushan fishing grounds after the close of the fishing season from September 2012 to January 2013. The vessels’ status (i.e. whether the vessels were fishing or not) were determined based on the integrated information of speed method and the simulated tracks. Generalized additive model (GAM) was built according to the logbook data of the 6 vessels in 2010, and then the GAM was applied to the AIS data of the same 6 vessels from September 2012 to January 2013 to estimate the monthly catches of these vessels in this period. The results show that the error of the simulated tracks increase with the increase in time interval, and the time interval of AIS data should be shorter than 30 minutes to prevent low accurate results. GAM can give viable estimates of catches when they do not greatly fluctuate over years. The step-by-step GAM analyses indicate that the factors, which affect catch, are ordered by their importance as date, sea surface salinity (SSS), latitude, sea surface temperature (SST), sea surface height (SSH) and longitude. This research is a new attempt for the study of fisheries resources in China using new data sources, which will be helpful for the improvement of fishery research in such datapoor countries as China.

Otter in Space by Sam Garton (review)

Otter in Space by Sam Garton (review)

Caesarean section in the Oriental small-clawed otter, Aonyx cinerea – a case report

Ein asiatisches Zwergotterweibchen (Aonyx cinerea), sechs Jahre alt und 3, 8 kg schwer, aus dem Zagreber Zoo hatte eine Totgeburt. Funf Tage spater beobachteten die Tierpfle-ger einen blutigeitrigen Ausfluss aus der Vagina und einen angeschwollenen Bauch. Radiologisch und ultrasonografisch wurden an der Klinik fur Geburtshilfe und Reproduktion der Tierarztlichen Fakultat der Universitat Zagreb drei tote Feten festgestellt, woraufhin den Besitzern eine Operation empfohlen wurde. Die Allgemeinanasthesie wurde mit Ketaminhydrochlorid (5 mg/kg BW i. m. ; Narketan® 10 ; Vetoquinol, CH) sowie Medetomidinhydrochlorid (50 mg/ kg BW i. m. ; Domitor® ; Orion Pharma, FIN) eingeleitet. Erhalten wurde die Anasthesie mittels einer Maske mit offenem MaplesSystem mit Sauerstoffdurchfluss von 2 l/min sowie mit Isofluran (Forane® ; Abbott Laboratories Ltd, UK) in einer Konzentration von 1, 5–4 %. Nach Eroffnen des Bauchraums wurde festgestellt, dass das linke Gebarmutterhorn perforiert war. Danach wurde die Gebarmutter mitsamt den Eierstocken entfernt (Sectio caesarea radicalis). Aufgrund des durchgefuhrten operativen Eingriffs konnte der klinische Befund von drei zuruckgebliebenen Feten samt Fruchthullen bestatigt werden. Nach der Operation erholte sich das Tier vollstandig.

The Deep-Sea Benthic Fish Fauna of the Northeastern Pacific Ocean on Cascadia and Tufts Abyssal Plains and Adjoining Continental Slopes

AbstractThe faunal composition of deep-sea fishes is described from 579 beam and otter trawl collections from the continental slope and abyssal plains off Oregon, at depths from 400 to 5,180 m. Ninety of the 104 species known to inhabit depths greater than 400 m in this area of the northeastern Pacific were captured. Sixty-one species were found on the continental slope, 28 on Cascadia Abyssal Plain, nine on eastern Tufts Abyssal Plain, and two on western Tufts Plain.Families represented by the most species were Scorpaenidae, Liparididae, and Zoarcidae on the slope, and Liparididae, Zoarcidae, and Macrouridae on the abyssal plains. Scorpaenids were numerically dominant on the upper slope, and macrourids on the mid-lower slope and abyssal plains. The macrourid Coryphaenoides armatus was caught at all abyssal stations and was consistently the most abundant fish at depths greater than 2,500 m. Coryphaenoides filifer and C. leptolepis were consistently the second and third most numerous species on Cascadia.Th...

Human Impacts on Seals, Sea Lions, and Sea Otters: Integrating Archaeology and Ecology of the Northeast Pacific

Review of Human Impacts on Seals, Sea Lions, and Sea Otters: Integrating Archaeology and Ecology of the Northeast Pacific. Todd J. Braje and Torben C. Rick, editors. 2011. University of California Press, Berkeley. Pp. 328. $65.00 (hardcover). ISBN 9780520267268.

Possible influence of increased riparian activity (stream modification and agricultural intensification) on abundance of South African otters

AbstractOtters are threatened by habitat loss and the pollution of their riverine habitat. Environmental impacts on top predators are often the first indication of habitat deterioration. It is rare for predator‐prey‐habitats to be monitored over long time intervals (decades), however necessary that may be. Here, we report on the decline in otter relative abundance in a previously pristine habitat and speculate on its causes. We surveyed sign of coexisting otters (Aonyx capensis and Lutra maculicollis) along a river in Kamberg Nature Reserve in uKhahlamba Drakensberg Park, KwaZulu‐Natal, South Africa. The area, Stillerust, lies downstream of a commercial dairy farm and a rural village–subsistence farming area. Data collected recently were compared with two previous surveys, carried out in 1972–1974 and 1993–1994, and were also compared with a pristine section of river in the nature reserve, upstream of the farming areas. At Stillerust, the number of spraint (scat) sites found, for each otter species, approximated only 25% of those recorded in the earlier studies. In the pristine section of the river, the amount of sign and abundance of otters were similar to those recorded in 1993. Assessments of stream biota and water quality analyses revealed negative changes in the river below the pristine area, down to, and including, Stillerust. Visible signs of pollution were evident. Since the 1970s, the rural village population has increased ca eightfold, and the commercial farm has changed from an extensive livestock enterprize to an intensive dairy farm.

To each his own taste: latrines of the giant otter as a food resource for vertebrates in Southern Pantanal, Brazil

Pteronura brasiliensis feeds mainly on fish and uses communal latrines for territorial marking. The aim of this study was to identify the vertebrate species associated with latrines of giant otters and which species use the feces as a food resource. From December 2010 to June 2011, we positioned camera traps in front of 21 latrines of six different giant otter groups in 24 h cycles monthly. We registered 29 vertebrate species at latrines. Latrines seem to be used as a frequent food resource for some species. Studies of giant otter diets should take into account possible changes in relative abundance of prey items due to consumption of feces. Pteronura brasiliensis se alimenta principalmente de peixes e utiliza latrinas para marcação territorial. O objetivo deste estudo foi identificar as espécies de vertebrados associadas a latrinas de ariranhas e as espécies que utilizam as fezes como fonte de recurso. De dezembro de 2010 a junho de 2011, posicionamos armadilhas fotográficas em frente a 21 latrinas de seis grupos de ariranhas distintos, mensalmente em ciclos de 24 h. Registramos 29 espécies de vertebrados em latrinas. Latrinas parecem ser utilizadas como um recurso freqüente por algumas espécies. Estudos sobre dieta de ariranhas devem considerar a possibilidade de alterações na abundância relativa dos itens de presas.

Increasing Damage to Tumor Blood Vessels during Motexafin Lutetium-PDT through Use of Low Fluence Rate

Photodynamic therapy (PDT) with low light fluence rate has rarely been studied in protocols that use short drug-light intervals and thus deliver illumination while plasma concentrations of photosensitizer are high, creating a prominent vascular response. In this study, the effects of light fluence rate on PDT response were investigated using motexafin lutetium (10 mg/kg) in combination with 730 nm light and a 180-min drug-light interval. At 180 min, the plasma level of photosensitizer was 5.7 ng/microl compared to 3.1 ng/mg in RIF tumor, and PDT-mediated vascular effects were confirmed by a spasmodic decrease in blood flow during illumination. Light delivery at 25 mW/cm(2) significantly improved long-term tumor responses over that at 75 mW/cm(2). This effect could not be attributed to oxygen conservation at low fluence rate, because 25 mW/cm(2) PDT provided little benefit to tumor hemoglobin oxygen saturation. However, 25 mW/cm(2) PDT did prolong the duration of ischemic insult during illumination and was correspondingly associated with greater decreases in perfusion immediately after PDT, followed by smaller increases in total hemoglobin concentration in the hours after PDT. Increases in blood volume suggest blood pooling from suboptimal vascular damage; thus the smaller increases after 25 mW/cm(2) PDT provide evidence of more widespread vascular damage, which was accompanied by greater decreases in clonogenic survival. Further study of low fluence rate as a means to improve responses to PDT under conditions designed to predominantly damage vasculature is warranted.

The Italian action plan for the endangered Eurasian otter Lutra lutra

Abstract Although recent evidence of the species recovery has been reported for many European countries, in Italy the Eurasian otter Lutra lutra is still considered endangered. Otter populations are confined to few river basins in the southern part of the peninsula and these are both geographically and genetically isolated from other European populations. This critical situation led the Italian Ministry of Environment to promote the production of an Action Plan for the otter in Italy, whose methods, aims and actions are briefly summarized. Riassunto Il Piano d'Azione Nazionale per la Lontra Lutra lutra Nonostante i segnali di recupero segnalati in molti paesi europei, la lontra Lutra lutra e ancora una delle specie piu minacciate della fauna italiana, in virtu delle piccole dimensioni della popolazione e del suo isolamento , sia geografico, sia genetico, dal resto delle popolazioni europee. Sulla base di queste considerazioni il Ministero dell’Ambiente e della Tutela del territorio e del Mare ha recentemente promosso la realizzazione di un Piano d’Azione Nazionale per la Conservazione della Lontra, i cui contenuti, obiettivi, e azioni sono riassunti in questo lavoro. doi:10.4404/hystrix-21.1-4483

Using ecosystem models to predict the effects of sea otter reintroduction to the west coast of Vancouver Island, British Columbia

Using ecosystem models to predict the effects of sea otter reintroduction to the west coast of Vancouver Island, British Columbia

Mustelid Spacing Patterns: Variations on a Theme by Mustela

This is a review of mustelid spacing patterns. The Mustelinae appear to have intrasexual territories where ♂♂ are territorial against ♂♂, ♀♀ against ♀♀, but there is extensive territory overlap between sexes. Mustelids of other subfamilies appear to have variations on this theme; usually female territories are replaced by territories of family groups of one adult ♀ and her most recent offspring. Sea otters and European badgers do not appear to fit into these organizational schemes. There is a strong correlation between degree of intrasexual territoriality, sexual dimorphism in body size, degree of body elongation and degree of carnivory. It is suggested that energy requirements of individuals may tie these correlations together.