Amitriptyline prevents CPT-11-induced early-onset diarrhea and colonic apoptosis without reducing overall gastrointestinal damage in a rat model of mucositis.

PURPOSE: Gastrointestinal mucositis (GIM) is one of the most debilitating side effects of the chemotherapy agent, irinotecan hydrochloride (CPT-11). The toll-like receptor (TLR) pathway is a key mediator implicated in the pathophysiology underlying GIM. The tricyclic antidepressant amitriptyline has been shown to inhibit TLR2 and TLR4 activity in in vitro models. The aim of this study was therefore to investigate the effect of amitriptyline on the development of GIM following CPT-11. METHODS: Male albino Wistar rats were treated with either CPT-11 (125 mg/kg, i.p., n = 18), amitriptyline (20 mg/kg, n = 18), both agents (n = 18), or vehicle control (n = 18) and killed at 6, 48, or 96 h. Differences between groups in measurements of gastrointestinal toxicity (diarrhea and weight loss), mucosal injury (apoptosis and histopathology score), colonic expression of TLRs, and pro-inflammatory cytokines were determined. RESULTS: CPT-11-induced diarrhea and colonic apoptosis were inhibited by amitriptyline at 6 h. However, rats were not protected from weight loss or mucosal injury over the time course of CPT-11-induced GIM. Interleukin-1 beta transcript expression was significantly decreased with amitriptyline treatment at 6 h, although protein expression did not differ between groups. There was no change in TLR4 or TLR2 expression in any group. CONCLUSIONS: Prophylactic amitriptyline was able to inhibit early intestinal damage in this rat model of CPT-11-induced GIM, but exacerbated late-onset injury. These findings do not support use of amitriptyline as an approach for mitigation of GIM in this setting.

Caffeic acid phenethyl ester abrogates bone resorption in a murine calvarial model of polyethylene particle-induced osteolysis.

Particle-induced bone loss by osteoclasts is a common cause of aseptic loosening around implants. This study investigates whether caffeic acid phenethyl ester (CAPE), a potent and specific inhibitor of nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1 and nuclear factor kappa B, at a low dose reduces bone resorption in a murine calvarial model of polyethylene (PE) particle-induced osteolysis. The effects of particles and CAPE treatment on gastrointestinal tract (GIT) histopathology were also evaluated. Mice were scanned using in vivo animal micro-computed tomography (µCT) as a baseline measurement. PE particles (2.82 × 10(9) particles/mL) were implanted over the calvariae on day 0. CAPE was administered subcutaneously (1 mg/kg/day) at days 0, 4, 7 and 10. Mice were killed at day 14 and serum was analysed for Type-1 carboxyterminal collagen crosslinks (CTX)-1 and osteoclast-associated receptor (OSCAR) levels. Ex vivo µCT scans were conducted to assess bone volume (BV) change and percentage area of calvarial surface resorbed. Calvarial and GIT tissue was processed for histopathology. By day 14, PE particles significantly induced calvarial bone loss compared with control animals as evidenced by resorption areas adjacent to the implanted PE in three-dimensional µCT images, an increase in percentage of resorbed area (p = 0.0022), reduction in BV (p = 0.0012) and increased Tartrate-resistant acid phosphatase positive cells. Serum CTX-1 (p = 0.0495) and OSCAR levels (p = 0.0006) significantly increased in the PE implant group. CAPE significantly inhibited PE particle-induced calvarial osteolysis, as evidenced by a significant reduction in surface bone resorption (p = 0.0012) and volumetric change (p = 0.0154) compared with PE only, but had no effect on systemic CTX-1. Neither particles nor CAPE had an effect on GIT histopathology.

Matrix metalloproteinases: do they play a role in mucosal pathology of the oral cavity?

Matrix metalloproteinases (MMPs) are critical factors in maintaining the integrity of mucosa and mediating normal biological processes. An imbalance between tissue levels of these mediators and their natural inhibitors is believed to underlie the pathophysiology of many diseases, including those affect the gastrointestinal and oral mucosae. The ongoing development of synthetic inhibitors of these mediators may provide opportunities to develop treatment modalities for patients suffering from these diseases. Understanding the role of MMPs in the pathophysiology of many diseases, however, is far from complete, and the improvement of pharmaceutical management strategies can only be achieved if the underlying process of these diseases is completely comprehended. This paper reviews the functions of matrix metalloproteinases and addresses their role in mediating mucosal pathologies with emphasis on oral mucosa.

In situ fatty acid profile of femoral cancellous subchondral bone in osteoarthritic and fragility fracture females: implications for bone remodelling.

We report here differences in the fatty acid profile of cancellous bone matrix, including n-3, n-6, mono- and poly-unsaturated, as well as saturated fats, between femoral heads from female OA (n=8, aged 68-88years), fractured neck of femur (#NOF) (n=19, 67-88years) and autopsy controls (CTRL) (n=4, 85-97years). Femoral heads were collected from individuals undergoing orthopaedic surgery for OA or #NOF; the fatty acid profile of sub-samples from the superior principal compressive and superior principal tensile regions were determined by gas chromatography. A total of 42 individual fatty acids were detected at varying concentrations with significant differences between subchondral bone from OA subjects, subchondral bone from #NOF subjects and subchondral bone from CTRL subjects, as well as between the superior principal compressive and superior principal tensile regions (for saturated fats only). Subchondral bone from OA subjects had higher total n-6 (OA=10.89±3.17, #NOF=11.11±1.83, CTRL=8.32±2.05, p=0.008) and total n-3 (OA=1.34±0.38, #NOF=1.19±0.18, CTRL=1.15±0.48, p=0.011) percentages than subchondral bone from #NOF subjects and subchondral bone from CTRL subjects, and there was no difference in the n-6:n-3 ratio, nor within the percentage of n-9 fatty acids. Arachidonic acid (OA=0.42±0.16, #NOF=0.26±0.06, CTRL=0.28±0.06, p=0.01), and γ-linolenic acid (OA=0.11±0.03, #NOF=0.05±0.02, CTRL=0.04±0.02, p<0.001) were higher in subchondral bone from OA subjects than subchondral bone from #NOF subjects and subchondral bone from CTRL subjects. In conclusion, there is a wide diversity of fatty acids in cancellous bone matrix from the femoral heads of OA and #NOF, suggesting they may have regulatory effects on inflammatory processes, and their metabolites. This article is part of a Special Issue entitled "Osteoarthritis".

Relationship between dose of methotrexate, apoptosis, p53/p21 expression and intestinal crypt proliferation in the rat.

Previous studies have shown that apoptosis is induced by cytotoxic chemotherapy and precedes hypoproliferation of intestinal crypt cells. However, the relationship between the degree of intestinal apoptosis and crypt cell hypoproliferation may not be directly related. The purpose of this study was to investigate the relationship between apoptosis and hypoproliferation with increasing doses of chemotherapy. Eleven groups of breast cancer-bearing DA rats were treated with two doses of methotrexate (MTX) i. m. at varying concentrations (0.5, 1.5, 2.5 and 5.0 mg/kg) or saline (control). Animals were killed at 6 or 24 h following treatment. The small and large intestines were examined for apoptosis, villous area (small intestine), crypt length and mitotic count per crypt. Immunohistochemical expression of p53 and p21(waf1/cip1) (p21) were examined quantitatively. Data were analysed using Peritz' F-test. Low dose MTX (0.5 mg/kg) did not change p53 expression at 6 h but induced a 15-fold increase in apoptosis in the crypts of the small intestine. This was associated with only a minor reduction in crypt cell proliferation. Higher doses of MTX increased p53 expression and caused a lower (7-fold) but more prolonged peak of apoptosis that was accompanied by reduced villous area, shortened crypts and a more profound reduction in crypt cell proliferation. Unlike the small intestine, apoptosis in the colon was 10-fold lower, proportional to the dose of MTX and did not induce overt damage. Expression of p21 did not change with any dose at either timepoint. We conclude that apoptosis is not always associated with crypt cell hypoproliferation and that the small intestine can recover after low dose MTX despite a heightened peak of apoptosis of crypt cells.

Interphalangeal sesamoid bones of the great toe: an anatomic variant demanding careful scrutiny of radiographs.

We describe a patient who was found to have two sesamoid bones at the interphalangeal joint of the right great toe after radiographs for dislocation of the joint. Recognition of the sesamoids required careful scrutiny of the films. Interphalangeal sesamoids may cause painful callosities plantar to the joint or may become incarcerated in a dislocated joint. Our patient made a good recovery. The presence of sesamoid bones on the medial and lateral sides of the joint was unusual.

Cerebral atrophy following shaken impact syndrome and other non-accidental head injury (NAHI).

PURPOSE OF THE STUDY: To determine the frequency of cerebral atrophy and microcephaly in a group of children with sequential MRI brain scans after surviving a non-accidental head injury (n = 16). METHODS: Serial head circumference measurements (OFC) were extracted and plotted on standard growth charts for each child retrospectively to determine the frequency of secondary microcephaly. Cerebral atrophy was diagnosed and quantified by measurement of the ventricular/cortical ratio on coronal images of the sequential scans. RESULTS: Acquired microcephaly was found in 15 children (93.8%) over a median follow-up period of 67.93 weeks. There was a significant reduction in the median Z-score for the OFC at the most recent follow-up when compared with that at presentation (p < 0.001, Wilcoxon Signed Rank Test). Cerebral atrophy was found to be the cause of the microcephaly in eight of the 15 children and was evident as early as 9 days after presentation. CONCLUSION: A large proportion of the cohort (93.8%) develops acquired microcephaly after an inflicted head injury and cerebral atrophy is responsible in half of these cases.

Outcome, observer reliability, and patient preferences if CTA, MRA, or Doppler ultrasound were used, individually or together, instead of digital subtraction angiography before carotid endarterectomy.

OBJECTIVES: To evaluate the accuracy of routinely available non-invasive tests (spiral computed tomographic angiography (CTA), time of flight magnetic resonance angiography (MRA), and colour Doppler ultrasound (DUS)), individually and together, compared with intra-arterial digital subtraction angiography (DSA) in patients with symptomatic tight carotid stenosis; and to assess the effect of substituting non-invasive tests for DSA on outcome, interobserver variability, and patient preference. METHODS: Patients referred from a neurovascular clinic were subjected prospectively to DUS imaging. The operator was blind to symptoms. Patients with a tight carotid stenosis on the symptomatic side were admitted for DSA. CTA and MRA were performed during the admission. The CTA, MRA, and DSA films were each read independently by two of six experienced radiologists, blind to all other data. RESULTS: 67 patients were included (34 had all four imaging procedures). DUS, CTA, and MRA all agreed with DSA in the diagnosis of operable v non-operable disease in about 80% of patients. CTA tended to underestimate (sensitivity 0.65, specificity 1.0), MRA to overestimate (sensitivity 1.0, specificity 0.57), and DUS to agree most closely with (sensitivity 0.85, specificity 0.71) the degree of stenosis as shown by DSA. When using any two of the three non-invasive tests in combination, adding the third if the first two disagreed would result in very few misdiagnoses (about 6%). MRA had similar interobserver variability to CTA (both worse than DSA). Patients preferred CTA over MRA and DSA. CONCLUSIONS: DUS, CTA, and MRA all show similar accuracy in the diagnosis of symptomatic carotid stenosis. No technique on its own is accurate enough to replace DSA. Two non-invasive techniques in combination, and adding a third if the first two disagree, appears more accurate, but may still result in diagnostic errors.

Magnetic resonance imaging in acute non-accidental head injury.

Making the diagnosis of non-accidental head injury, particularly in the acute illness, can be difficult. The aim of this retrospective study was to evaluate the use of magnetic resonance imaging in the acute presentation of non-accidental head injury. Twelve cases admitted to the Royal Hospital for Sick Children, Edinburgh with a diagnosis of non-accidental head injury, and who had magnetic resonance imaging in the acute illness, were identified. The average age was 5.7 mo (range 1 to 34 mo). The mechanism of the primary injury was whiplash-shaking injury syndrome with impact in four cases and without evidence of impact in seven; in one case there was a compression injury. The magnetic resonance imaging findings reflected the pathological consequences of rotational acceleration-deceleration injury and did not differ between those cases with evidence of impact and those without. Subdural haematomas were identified in all cases; the commonest location for subdural blood was the subtemporal region. It is surprising and important that the most frequent location of subdural blood was in the subtemporal area. This is an area difficult to assess by computerized tomography. Evidence of repeated injuries was found in two cases. These findings confirm the value of magnetic resonance imaging in the acute phase of non-accidental head injury.

Further observations of the ovarian response of the tammar wallaby (Macropus eugenii) to exogenous gonadotrophins: an improved method for superovulation using FSH/LH.

This study reports the development of an improved superovulation protocol in the monovulatory tammar wallaby, Macropus eugenii. Treatment with pregnant mare's serum gonadotrophin (PMSG; 10-20 IU) inhibited follicle development in the corpus luteum (CL)-bearing ovary and only 2-3 eggs per female could be recovered after ovulation induction with gonadotrophin releasing hormone (GnRH; 3 x 30 microg at 3-h intervals) or porcine luteinizing hormone (LH; 4, 5 or 8 mg) 3 days after PMSG priming. Treatment with porcine FSH (8 x 6 mg at 12-h intervals for four consecutive days) was found to override this inhibition and resulted in the recovery of 7-13 eggs per female after ovulation induction with porcine LH (4 mg on day 5). For these animals, there was no difference in numbers of developing follicles, ovulation sites and eggs recovered between the CL- and non-CL-bearing ovaries. This FSH/LH protocol was effective in both cycling and non-cycling females, and multiple ovulation occurred from about 36 h after LH treatment. After LH treatment, eggs were recovered from the oviduct at 36-50 h. At 51-57 h, 12-25% of eggs were recovered from the uterus, and by 75 h all eggs were recovered from the uterus. It is concluded that the described FSH/LH protocol used results in higher ovulation success than the PMSG/GnRH method.

Successful fertilization after superovulation and laparoscopic intrauterine insemination of the brushtail possum, Trichosurus vulpecula, and tammar wallaby, Macropus eugenii.

Fertilization has been achieved in superovulated brushtail possums and tammar wallabies after laparoscopic intrauterine artificial insemination. Various superovulation protocols and insemination times were examined but a maximum of 2-5 eggs including 1-2 embryos per possum were recovered. The female possums were superovulated by treatment with 15 iu pregnant mares' serum gonadotrophin and then either GnRH (4 x 50 micrograms, at intervals of 90 min) or 4 mg LH, 3 days later. Inseminations were performed within 6 h before or 4-10 h after (pregnant mares' serum gonadotrophin-GnRH group only) the expected onset of ovulation using epididymal spermatozoa. Superovulation in wallabies was achieved by treatment with FSH (8 x 6 mg, at intervals of 12 h for 4 days) followed by 4 mg LH on day 5. Inseminations were performed 4-6 h before the expected onset of ovulation using ejaculated spermatozoa, which resulted in the recovery of 7-8 eggs including 3-4 embryos per female. All embryos recovered were from possums and wallabies examined 1-2 days after insemination and included fertilized eggs, two-cell and four-cell embryos. Motile spermatozoa were recovered from the oviducts and uteri but only immotile spermatozoa were found in the vaginal complex. Five to thirty per cent of spermatozoa recovered from the oviducts of possums examined 2-6 h after insemination had thumbtack morphology, which is thought to be correlated with capacitation. Although embryo yields per female were low, this study has established that intrauterine artificial insemination after superovulation is a feasible assisted breeding strategy for marsupials with implications for species conservation and population control.

The effect of angiographic technique and image quality on the reproducibility of measurement of carotid stenosis and assessment of plaque surface morphology.

We studied the reproducibility of measurement of carotid stenosis and assessment of plaque surface morphology on 1001 angiograms from a consecutive series of patients entered into the European Carotid Surgery Trial. Inter-observer agreement (Kappa statistic, 95% confidence interval (CI)) for categorization of carotid stenosis, as 0-29%, 30-69% or 70-99% was good (0.68, 0.63-0.73) on 789 conventional or digitally subtracted selective angiograms, and good (0.64, 0.54-0.75) on 174 conventionally and digitally subtracted aortic arch injection angiograms, but was poor (0.29, 0.02-0.80) on 29 intravenous digital subtraction angiograms. Inter-observer agreement did not vary with the method of image acquisition of arterial angiograms, but was dependent on the quality of visualization of the stenosis: kappa = 0.73 (0.67-0.79) for good quality angiograms vs. 0.54 (0.44-0.64) for poor quality angiograms. Inter-observer agreement for assessment of plaque surface morphology was moderate (kappa 0.4-0.6) and did not vary with type of angiography or method of image acquisition. However, ulceration was reported most frequently on selective angiograms and on those angiograms on which the quality of visualization of the stenosis was good. We conclude that the reproducibility of measurement of carotid stenosis and the assessment of plaque surface morphology vary depending on the type of angiography and the quality of visualization of the stenosis. This should be taken into account when validating non-invasive methods of imaging the carotid bifurcation.

Aggressive behaviour in intellectually challenged patients with epilepsy treated with lamotrigine.

PURPOSE: Lamotrigine (LTG) is a valuable addition to the medical management of epilepsy with wide spectrum of efficacy and good outcomes for quality of life. We report the emergence of a syndrome of aggressive behavior provoked by LTG in patients with epilepsy and intellectual challenge. METHODS: On recognition of a tendency to aggression in intellectually challenged patients whose epilepsy was treated with LTG, a survey was conducted of those from centers specializing in management of patients with intellectual disability who were treated with LTG. Responses to LTG were sought and patient's behavioral profiles were determined. RESULTS: Nineteen patients were identified (16 men, 3 women, aged 17-54 years). Five patients discontinued LTG due to unprovoked aggressive behavior subsequent to its use; 2 had aggressive behavior sufficient to justify discontinuation of LTG but required reintroduction to control the epilepsy; 1 required reduction in LTG dosage; 1 had aggression that responded to psychiatric intervention; and 1 had aggression unrelated to LTG. Four patients had behavioral problems other than aggression, 4 had no change in behavior, and the behavior of 1 was improved by LTG treatment. CONCLUSIONS: LTG may provoke aggressive behavior and violence in intellectually handicapped patients with epilepsy, which may limit its use in such patients. Acknowledgment of the potential for such disturbance justifies greater surveillance of these patients and early discontinuation of LTG if necessary.