Use of functional brain imaging in the evaluation of exposure to mycotoxins and toxins encountered in Desert Storm/Desert Shield

In this retrospective analysis the authors compared brain scintigrams, performed using triple-head single-photon emission computed tomography (tripleSPECT), of subjects who were judged clinically impaired from exposure to toxins during the Desert Storm/Desert Shield military action, and of subjects exposed to mycotoxins, with those of normal controls. The scintigrams for both exposed groups exhibited similar patterns of abnormalities, which were consistent with neurotoxic impairment. The authors conclude that further study is needed to determine whether mycotoxin exposure may be a cause of abnormalities seen in tripleSPECT images.     

Trials of daily, long-term minocycline and rifampin or clarithromycin and rifampin in the treatment of borderline lepromatous and lepromatous leprosy

Daily, long-term treatment with minocycline 100 mg and rifampin 600 mg was initiated in 24 previously untreated borderline lepromatous (BL) and lepromatous (LL) patients for a total of 646 patient-months, averaging 26.9 months per patient. The same regimen was started in 12 BL and LL patients having a bacteriologic relapse for a total of 379 patient-months, averaging 32.5 months per patient, and in 12 patients judged to be at high risk for relapse for a total of 354 patient-months, averaging 29.5 months per patient. Daily, long-term treatment with clarithromycin 500 mg and rifampin 600 mg was initiated in 8 previously untreated BL and LL patients for a total of 174 patient-months, averaging 21.8 months per patient. The results in these 56 patients were compared to those obtained in 34 previously untreated BL and LL patients who were treated concurrently receiving daily, long-term dapsone 100 mg and rifampin 600 mg. No evidence of dangerous drug reactions or bone marrow, kidney or liver toxicity was seen in any of these five patient groups. Drug intolerance in 10 of the 90 patients studied necessitated discontinuing the chosen regimen, 4 from rifampin, 3 from dapsone, 2 from minocycline and 1 of undetermined attribution. The use of either minocycline or clarithromycin in conjunction with rifampin appears to pose no great risk when used long term.     

From the Cover: Thuricin CD,a posttranslationally modified bacteriocin with a narrow spectrum of activity against Clostridium difficile

The last decade has seen numerous outbreaks of Clostridium difficile-associated disease (CDAD), which presented significant challenges for healthcare facilities worldwide. We have identified and purified thuricin CD, a two-component antimicrobial that shows activity against C. difficile in the nanomolar range. Thuricin CD is produced by Bacillus thuringiensis DPC 6431, a bacterial strain isolated from a human fecal sample, and it consists of two distinct peptides, Trn-α and Trn-β, that act synergistically to kill a wide range of clinical C. difficile isolates, including ribotypes commonly associated with CDAD (e.g., ribotype 027). However, this bacteriocin thuricin CD has little impact on most other genera, including many gastrointestinal commensals. Complete amino acid sequencing using infusion tandem mass spectrometry indicated that each peptide is posttranslationally modified at its respective 21st, 25th, and 28th residues. Solution NMR studies on [¹³C,¹⁵N] Trn-α and [¹³C,¹⁵N]Trn-β were used to characterize these modifications. Analysis of multidimensional NOESY data shows that specific cysteines are linked to the α-carbons of the modified residues, forming three sulfur to α-carbon bridges. Complete sequencing of the thuricin CD gene cluster revealed genes capable of encoding two S′-adenosylmethionine proteins that are characteristically associated with unusual posttranslational modifications. Thuricin CD is a two-component antimicrobial peptide system with sulfur to α-carbon linkages, and it may have potential as a targeted therapy in the treatment of CDAD while also reducing collateral impact on the commensal flora.     

Persistent chylothorax in lymphangioleiomyomatosis treated by intrapleural instillation of povidone.

Lymphangioleiomyomatosis (LAM) is a rare, idiopathic disease affecting young women often complicated by refractory and difficult to manage chylothorax. We report one case of a patient who received a bilateral lung transplantation for LAM presenting a refractory chylothorax. The instillation of povidone iodine in the pleural space was effective in inducing pleurodesis.     

What advice are oncologists and surgeons in the United Kingdom giving to breast cancer patients about physical activity?

Evidence has shown that physical activity may attenuate the negative physical, psychological and functional effects of treatment in women diagnosed with breast cancer. Physical activity levels also decline substantially during and after completion of treatment for cancer, highlighting the importance of strategies to promote participation in regular physical activity in this population. Oncologists and surgeons may serve as an influential source of motivation to be physically activity in cancer patients, by conveying the importance of a healthy lifestyle. The primary purpose of the present study was to investigate whether oncologists and surgeons routinely discuss physical activity with their breast cancer patients and to investigate the nature of any information/advice provided during consultations. A secondary aim was to examine whether physically active oncologists and surgeons were more likely to provide advice about physical activity to patients, than inactive oncologists and surgeons. A brief postal questionnaire was sent to 710 consultant breast cancer oncologists and surgeons throughout the UK and 102 responded (response rate = 14.4%). Of responders, most (55.9%) did not routinely discuss physical activity with their patients. Amongst oncologists/surgeons (clinicians) who did offer advice, most focussed on discussing the benefits of physical activity for physical and functional health gains and for facilitating weight control and maintenance. A number of clinicians indicated they advised patients that physical activity may decrease risk of recurrence and improve survival, despite the lack of evidence from RCTs to support this suggestion. There was no significant association between the physical activity status of oncologists/surgeons and the likelihood that they discussed physical activity with patients. Educational strategies aimed at encouraging clinicians to promote physical activity in consultations need to be targeted widely amongst the cancer clinician community.     

Endocannabinoid-mediated enhancement of fear-conditioned analgesia in rats: Opioid receptor dependency and molecular correlates

The opioid and endocannabinoid systems mediate analgesia expressed upon re-exposure to a contextually aversive stimulus (fear-conditioned analgesia; FCA), and modulate the mitogen-activated protein kinase (MAPK) pathway. However, an interaction between the opioid and endocannabinoid systems during FCA has not been investigated at the behavioural or molecular level. FCA was modeled in male Lister-hooded rats by assessing formalin-evoked nociceptive behaviour in an arena previously paired with footshock. Administration of the fatty acid amide hydrolase and endocannabinoid catabolism inhibitor, URB597 (0.3 mg/kg, i.p.), enhanced expression of FCA. The opioid receptor antagonist, naloxone, attenuated FCA and attenuated the URB597-induced enhancement of FCA. SR141716A (CB₁ antagonist) and SR144528 (CB₂ antagonist) also attenuated the URB597-mediated enhancement of FCA. Expression of FCA was associated with increased relative phospho-ERK2 expression in the amygdala, an effect blocked by naloxone, SR141716A, and SR144528. Furthermore, URB597-mediated enhancement of FCA was associated with reduced phospho-ERK1 and phospho-ERK2 in the amygdala. Phospho-ERK1/2 expression in the hippocampus, prefrontal cortex, and thalamus was unchanged following FCA and drug treatment. None of the drugs affected formalin-evoked nociceptive behaviour or phospho-ERK1/2 expression in non-fear-conditioned rats. These data suggest that endocannabinoid-mediated enhancement of FCA is abolished by pharmacological blockade of opioid receptors as well as CB₁ or CB₂ receptors. Both pharmacological enhancement (with URB597) and attenuation (with naloxone) of this form of endogenous analgesia were associated with reduced expression of phospho-ERK1/2 in the amygdaloid complex arguing against a causal role for ERK1/2 signaling in the amygdala during expression of FCA or its modulation by opioids or cannabinoids.