Neurotoxicity following the ingestion of a Chinese medicinal plant, Alocasia macrorrhiza

1. A case of poisoning due to the raw root tuber of a Chinese medicinal plant, Alocasia macrorrhiza is presented. 2. The patient developed neurological (severe pain and numbness in the perioral area and throat) and gastrointestinal (nausea, vomiting, abdominal pain) symptoms immediately after eating the root tuber. 3. A macrorrhiza has properties and morphology very similar to another medical plant. A. odora. The root tuber of the latter is known to contain a neurotoxin sapotoxin.     

A stingray spine in the scapula of a bottlenose dolphin

A stingray spine was found lodged in the scapula of a deceased 272 cm, male bottlenose dolphin (Tursiops truncatus) from South Carolina (USA) following skeletal preparation, nearly 6 mo after necropsy. No external puncture wound, internal bruising, or laceration of muscle tissue surrounding the scapula was evident during necropsy of the animal. Implantation of the spine did not appear to be related to the death of the dolphin, but probably occurred at an early age. Abnormal development of bone surrounding the spine resulted in the formation of a cavity at the wound site. Two mechanisms were considered as contributors for the cavity formation. These were the mechanical action of the spine stimulating the body's defense system for managing foreign objects, and the release of potent toxins from the spine sheath.     

Visual, cognitive, and neurodevelopmental outcome at 51/2 years in children with perinatal haemorrhagic-ischaemic brain lesions

To determine predictive values of early visual and neurocognitive assessment in children with perinatally acquired haemorrhagic or ischaemic brain lesions selected on the basis of ultrasound, 63 children (37 boys, 26 girls), who had been followed and examined until the age of 18 months, were reexamined at 5 1/2 years. Good correlations between visual and neurodevelopmental assessments at 18 months and at 5 1/2 years were found. When ultrasound abnormalities were combined with early visual and neurocognitive assessment data, good predictive values, especially for the group of children who had grade 2 to 4 leukomalacia, were found for visual acuity and neurodevelopment.     

Neurobiology and sexual orientation: current relationships

Despite great progress in the neurosciences, our understanding of the determinants of sexual orientation is incomplete. The authors review for the clinician/neuropsychiatrist studies pertaining to the formation of sexual orientation in the following areas: hormone effects on sexual behavior (animal and human); the complicated relationship between gender identity, gender role, and sexual orientation in humans; cross-cultural studies of homosexuality; behavioral observations in pseudohermaphrodites and offspring of mothers treated with hormones during pregnancy; brain studies of homosexual and heterosexual individuals; and genetic studies. The authors conclude that human sexual orientation is complex and diversely experienced and that a biopsychosocial model best fits the current state of knowledge in the field.     

Cortical cholinergic impairment and behavioral deficits produced by kainic acid lesions of rat magnocellular basal forebrain.

The rat magnocellular basal forebrain (MNBF) is homologous to the human nucleus basalis of Meynert, a structure implicated in the cholinergic hypothesis of cognitive impairment in Alzheimer's disease (AD). In the present study, 18 male Sprague-Dawley rats with kainic acid lesions in the MNBF were compared with 6 unoperated controls, 10 sham-operated controls, and 6 controls injected with kainic acid in the cortical area directly above the MNBF. MNBF lesions depleted choline acetyltransferase in cortex but not in striatum or hippocampus. Cortical dopamine levels were unchanged; serotonin levels were unchanged in hippocampus and parietal cortex but decreased in frontal cortex. Compared with controls, MNBF-lesioned Ss were impaired in 24-hr retention, but not acquisition, of a passive avoidance task with escapable footshock. The groups did not differ in mean number of daily avoidances on a barpress active avoidance task, although learning was slower in MNBF-lesioned Ss. In a serial spatial discrimination reversal test, MNBF-lesioned Ss performed significantly worse than controls. This model may be useful for studying the role of the cholinergic system in memory and possibly for developing treatment strategies to alleviate the cognitive dysfunction of AD. (63 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Potent and selective bicyclic lactam inhibitors of thrombin: Part 2: P1 modifications

The synthesis and antithrombotic activity of a series of nonpeptide bicyclic thrombin inhibitors is described. We have explored the SAR with modifications to the P1 site. The introduction of arginine mimetics at the P1 site led to potent and selective thrombin inhibitors.     

An economic evaluation of the use of rare earth screens to reduce the radiation dose from diagnostic X-ray procedures in Israel

In Israel the diffusion of rare earth screen technology has been limited. These screens could halve the radiation dose to the patient from diagnostic X-ray radiography, with little managerial effort and without being detrimental to the quality of the diagnostic image. We estimated the total effective dose from diagnostic film radiography capable of reduction by the use of rare earth screens, based on the number of hospital and ambulatory diagnostic X-ray procedures. This number was multiplied by the computed radiation dose per body site for a series of diagnostic procedures. The annual dose was approximately 0.53 mSv per head, approximately half of which could be averted by the introduction of rare earth screen technology. Based on a fatality risk of 3% Sv-1, it is estimated that the adoption of rare earth screen technology might reduce the annual incidence of cancer by some 93 cases, half of which would be fatal after an average latency period of 18.4 years. The cost of purchasing rare earth screens on a nationwide basis is approximately $3.0 million. This cost is outweighed by a saving of $9.6 million in X-ray tube replacement costs over the period 1997-2006. Government legislation enforcing the use of rare earth screens is essential, because of the lack of prestige associated with acquiring rare earth technology, as well as institutional reluctance to accept the external benefits of reduced morbidity and mortality and/or to extend budgetary time horizons.     

1998 William J. Stickel Bronze Award. Antifungal activity of Melaleuca alternifolia (tea-tree) oil against various pathogenic organisms

Tea-tree oil (oil of Melaleuca alternifolia) has recently received much attention as a natural remedy for bacterial and fungal infections of the skin and mucosa. As with most naturally occurring agents, claims of effectiveness have been only anecdotal; however, several published studies have recently demonstrated tea-tree oil's antibacterial activity. This study was conducted to determine the activity of tea-tree oil against 58 clinical isolates: Candida albicans (n = 10), Trichophyton rubrum (n = 8), Trichophyton mentagrophytes (n = 9), Trichophyton tonsurans (n = 10), Aspergillus niger (n = 9), Penicillium species (n = 9), Epidermophyton floccosum (n = 2), and Microsporum gypsum (n = 1). Tea-tree oil showed inhibitory activity against all isolates tested except one strain of E floccosum. These in vitro results suggest that tea-tree oil may be useful in the treatment of yeast and fungal mucosal and skin infections.     

Depressive symptom reversal for women in a primary care setting: a pilot study

Our goal is to assess the viability of an in vitro preparation of bovine ciliary body/epithelium (CBE) in a small volume Ussing-type chamber. A new small volume Ussing-type chamber with continuous perfusion was developed for bovine CBE. The trans-CBE electrical parameters were monitored and the electrical responses of the CBE to ouabain (1 and 0.01 mM) were recorded. The trans-CBE fluxes of [14C]-L-ascorbate and [3H]-L-glucose were also studied. The bovine CBE preparation was stable inside the chamber in terms of its potential difference (PD), short circuit current (SCC) and trans-CBE resistance. They were -0.51+/-0.05 mV (aqueous side negative), -5.43+/-0.04 microAcm-2 and 94+/-2 Q.cm2 (mean s.e.m., n=35), respectively. The preparation hyperpolarised when 0.01 mM ouabain was administered to the aqueous side, depolarised when ouabain was applied to the stromal side. [3H]-L-glucose diffusion was about 74 nEq h(-1)cm(-2) in either direction (n=12). Taking the area magnification factor of the CBE into consideration, the diffusional L-glucose flux across the bovine CBE was comparable to other tight epithelia. A significant net ascorbate flux (0.26+/-0.05 nEq h(-1)cm(-2), n=4, p<0.01) was found in the stroma to aqueous direction. We have developed a viable in vitro bovine CBE preparation which was (1) electrically stable, (2) responsive to ouabain, (3) tight to L-glucose diffusion, and (4) capable of actively secreting ascorbate. A net trans-CBE chloride transport (0.81+/-0.30 microEq h(-1)cm(-2), n=12, p=0.01) from stromal to aqueous side was found in the present in vitro model under short-circuited conditions.     

Lysophosphatidylcholine is involved in the antigenicity of oxidized LDL

Lysophosphatidylcholine (LPC) is formed by hydrolysis of PC in low density lipoprotein (LDL) and cell membranes by phospholipase A2 or by oxidation. Oxidized (ox) LDL activates endothelial cells, an effect mimicked by LPC. oxLDL also has the capacity to activate T and B cells, and antibody titers to oxLDL are related to the degree of atherosclerosis. The antigen in oxLDL responsible for its immune-stimulatory capacity is not well characterized, and we hypothesized that LPC was involved. We demonstrate herein the presence of antibodies against LPC, both of the IgG and IgM isotype, in 210 healthy individuals. This antibody reactivity was not specifically related to oxidation of the fatty acid moiety in LPC, since LPC containing only palmitic acid showed antibody titers equivalent to those of LPC containing unsaturated fatty acids. Antibody titers to PC were low compared with LPC, and hydrolysis of PC at the sn-2 position is thus essential for immune reactivity. There was a close correlation between anti-oxLDL and anti-LPC antibodies. Furthermore, LPC competitively inhibited anti-oxLDL reactivity, which indicates that LPC may explain a significant part of the immune-stimulatory properties of oxLDL. LPC, being a lipid, is not likely to be an antigen itself. Instead, LPC could form immunogenic complexes with peptides, which may induce and potentiate immune reactions in the vessel wall. This study adds to the evidence that LPC is an important component of oxLDL and emphasizes the potential role of phospholipase A2 in atherosclerosis.