Expression of leptin and iNOS in oral melanomas in dogs

BACKGROUND

Oral melanoma (OM) in dogs is an aggressive malignancy, with clinical behavior resembling cutaneous melanomas in humans. Melanoma in humans is promoted by an inflammatory environment that is contributed to by leptin and inducible nitric oxide synthase (iNOS).

OBJECTIVE

To determine if the patterns of leptin and iNOS expression are similar in OM in dogs and cutaneous melanomas in humans.

ANIMALS

Twenty client-owned dogs.

METHODS

Retrospective case study. Immunostaining of the OM tumors from each dog was scored for percentage and intensity of leptin and iNOS expression. Mitotic index was used as an indicator of tumor aggression.

RESULTS

Leptin was detected in ≥75% of the tumor cells in specimens from 11 dogs. One tumor expressed leptin in ≤25% of the cells. The intensity of leptin expression was variable with 6, 9, and 5 cases exhibiting low-, moderate-, and high-intensity staining, respectively. OM with the lowest percentage of iNOS positive cells displayed the highest mitotic indices (P = .006, ANOVA).

CONCLUSIONS AND CLINICAL IMPORTANCE

The expression of leptin is a common finding in melanomas in dogs. These data suggest that the possibility of future clinical applications, such as measuring the concentrations of plasma leptin as a screening tool or leptin as a target for therapy. The relevance of iNOS is not as clear in dogs with OM, for which other directed therapeutics might be more appropriate.

The reversible cerebral vasoconstriction syndrome in association with venlafaxine and methenamine

The reversible cerebral vasoconstriction syndrome (RCVS) is characterised by thunderclap headache and multifocal vasoconstriction of cerebral arteries on angiography. It is often drug induced, but it can occur postpartum, and as a result of a number of other precipitants. To make the diagnosis, it is necessary to exclude other causes of severe headache (such as aneurysmal subarachnoid haemorrhage, carotid dissection and primary angiitis of the central nervous system). However, it is also important to show that the vasoconstriction has resolved with repeat angiography at the 3-month stage. Here we report two cases of RCVS in association with venlafaxine and the urinary antiseptic, methenamine. Serotonin-norepinephrine reuptake inhibitors have recently been reported as a possible precipitant, but this is the first report to implicate methenamine. Although RCVS is relatively uncommon, it should be considered in the differential of those presenting with thunderclap headache.

UK national guideline on safer sex advice

This guideline provides evidence-based guidance on the content of safer sex advice and the provision of brief behaviour change interventions deliverable in genitourinary (GU) medicine clinics. Much of the advice is applicable to other healthcare settings including general practice and clinics providing HIV care. Advice on condom use and effectiveness, oral sex and other sexual practices, testing for sexually transmitted infections (STI) and partner reduction is provided. Advice specific to the transmission of HIV infection including seroadaptive behaviours and negotiated safety is also included. An accompanying review of the evidence supporting the guideline with a complete reference list is available online. A patient information leaflet based on the advice statements developed is also available through the BASHH website.

Testosterone Induces an All-or-None, Exponential Increase in Arginine Vasopressin mRNA in the Bed Nucleus of Stria Terminalis of the Hypogonadal Mouse

The bed nucleus of the stria terminalis (BNST) in rodents contains arginine vasopressin (AVP) neurons which project to the lateral septum (LS) and habenula (LH) and are thought to be important for social recognition or memory. In previous studies we demonstrated that AVP immunoreactivity in the LS and LH is absent in the hypogonadal (hpg) mouse and that AVP immunoreactivity in the LH and LS of this mutant can be induced by testosterone. The aim of the present study was to determine whether this action of testosterone was due to the induction of AVP gene expression in BNST neurons and if so the time taken for testosterone to exert its effect. We found that exposure to supraphysiological concentrations of testosterone for 6-12 days caused an exponential, 50-fold increase in the number of cells that expressed AVP mRNA in the BNST in hpg mice. The action of testosterone is "all-or-none" in that the level of AVP mRNA in the AVP-positive cells was similar at all times after testosterone implantation and also similar or less than that in the few AVP-positive cells in animals not treated with testosterone. The relatively long time taken for testosterone to exert its effect on AVP mRNA in BNST neurons is comparable to its effects on AVP immunoreactivity in the LH and LS and on behaviour and suggests that the action of testosterone may be mediated by indirect or slow intracellular transduction mechanisms.

Contrast imaging ultrasound detects abnormalities in the marmoset ovary

The development of a functional vascular tree within the primate ovary is critical for reproductive health. To determine the efficacy of contrast agents to image the microvascular environment within the primate ovary, contrast ultrasonography was performed in six reproductive-aged female common marmosets (Callithrix jacchus) during the late luteal phase of the cycle, following injection of Sonovue™. Regions of interest (ROIs), representing the corpus luteum (CL) and noncorpus luteum ovarian tissue (NCLOT), were selected during gray-scale B-mode ultrasound imaging. The magnitude of backscatter intensity of CL and NCLOT ROIs were calculated in XnView, post hoc: subsequent gamma-variate modeling was implemented in Matlab to determine perfusion parameters. Histological analysis of these ovaries revealed a total of 11 CL, nine of which were identified during contrast ultrasonography. The median enhancement ratio was significantly increased in the CL (5.54AU; 95% CI -2.21-68.71) compared to the NCLOT (2.82AU; 95% CI 2.73-15.06; P < 0.05). There was no difference in time parameters between the CL and NCLOT. An additional avascular ROI was identified in the ovary of Animal 5, both histologically and by ultrasonography. This cystic ROI displayed a markedly lower enhancement ratio (0.79AU) and higher time parameters than mean CL and NCLOT, including time to peak and time to wash out. These data demonstrate, for the first time, the ability of commercially available contrast agents, to differentiate structures within the nonhuman primate ovary. Contrast-enhanced ultrasonography has a promising future in reproductive medicine.

Effect of tolfenamic acid on canine cancer cell proliferation, specificity protein (sp) transcription factors, and sp-regulated proteins in canine osteosarcoma, mammary carcinoma, and melanoma cells

BACKGROUND

Tolfenamic acid (TA) is an NSAID currently under investigation as an anticancer agent in humans. TA induces proteosome-dependent degradation of transcription factors Sp 1, 3, and 4. These proteins are known to be overexpressed in many human cancers.

HYPOTHESIS

To evaluate the protein expression of Sps in canine tissue, and efficacy of TA against several canine tumor cell lines.

METHODS

Six canine cell lines (2 osteosarcoma, 2 mammary carcinoma, 2 melanoma) were evaluated. Protein levels of Sp 1-4 and their downstream targets were evaluated using Western Blots. Cell survival and TUNEL assays were performed on cell lines, and Sp1 expression was evaluated on histologic samples from archived canine cases.

ANIMALS

Six immortalized canine cancer cell lines derived from dogs were used. Archived tissue samples were also used.

RESULTS

Sps were highly expressed in all 6 cell lines and variably expressed in histologic tissues. TA decreased expression of Sps 1-4 in all cell lines. All of the downstream targets of Sps were inhibited in the cell lines. Variable Sp1 expression was identified in all histologic samples examined. TA significantly inhibited cell survival in all cell lines in a dose dependant fashion. The number of cells undergoing apoptosis was significantly increased (P < .05) in all cell lines after exposure to TA in a dose-dependent fashion. CONCLUSIONS, AND CLINICAL IMPORTANCE: Tolfenamic acid is a potential anticancer NSAID and further investigation is needed to determine its usefulness in a clinical setting.

PAR(2) expression in peripheral blood monocytes of patients with rheumatoid arthritis

OBJECTIVES

Proteinase-activated receptor 2 (PAR(2)) is a G protein-coupled receptor activated by serine proteinases with proinflammatory activity. A study was undertaken to investigate the presence and functional significance of PAR(2) expression on rheumatoid arthritis (RA)-derived leucocyte subsets.

METHODS

Venous blood was obtained from patients with RA and osteoarthritis (OA) as well as healthy control subjects. Surface expression of PAR(2) on peripheral blood mononuclear cells (PBMCs) was analysed by flow cytometry and interleukin 6 (IL-6) generation by ELISA.

RESULTS

Patients with RA had elevated but variable surface expression of PAR(2) on CD14+ monocytes compared with control subjects (median (1st to 3rd quartiles) 1.76% (0.86-4.10%) vs 0.06% (0.03-0.81%), p<0.0001). CD3+ T cells showed a similar pattern with significantly higher PAR(2) expression in patients with RA compared with controls (3.05% (0.36-11.82%) vs 0.08% (0.02-0.28%), p<0.0001). For both subsets, PAR(2) expression was significantly higher (p<0.00001) in patients with high levels of disease activity: PAR(2) expression for both CD14+ and CD3+ cells correlated to C reactive protein and erythrocyte sedimentation rate. Furthermore, in a cohort of patients with newly diagnosed RA, elevated PAR(2) expression in both CD14+ and CD3+ cells was significantly reduced 3 months after methotrexate or sulfasalazine treatment and this reduction correlated significantly with the reduction in the 28-joint Disease Activity Scale score (p<0.05). PAR(2) expression on cells from patients with OA was low, similar to levels seen in control subjects. Generation of IL-6 by monocytes in response to a selective PAR(2) agonist was significantly greater in patients with RA than in patients with OA and control subjects (p<0.05).

CONCLUSIONS

These findings are consistent with a pathogenic role for PAR(2) in RA.

Some Effects of a Hemicholinium Compound (HC-3) on Neuromuscular Transmission in the Cat

The hemicholinium compound 4, 4′-biphenylylenebis[carbonylmethyl-(2-hydroxyethyl)dimethylammonium bromide] (HC-3) (Long and Schueler, 1954) has been shown to produce a neuromuscular block in rabbits which is of gradual onset, long duration (Reitzel and Long, 1959) and dependent on the frequency of nerve stimulation (Wilson and Long, 1959).

An attempt has been made in the present study to determine the effect of HC-3 on neuromuscular transmission in the cat by using the tibialis anterior muscle-sciatic nerve preparation. Some effects on this preparation have already been described by Bowman and Rand (1961).

Nonlinear simulations of peeling-ballooning modes with anomalous electron viscosity and their role in edge localized mode crashes

A minimum set of equations based on the peeling-ballooning (P-B) model with nonideal physics effects (diamagnetic drift, E×B drift, resistivity, and anomalous electron viscosity) is found to simulate pedestal collapse when using the new BOUT++ simulation code, developed in part from the original fluid edge code BOUT. Nonlinear simulations of P-B modes demonstrate that the P-B modes trigger magnetic reconnection, which leads to the pedestal collapse. With the addition of a model of the anomalous electron viscosity under the assumption that the electron viscosity is comparable to the anomalous electron thermal diffusivity, it is found from simulations using a realistic high-Lundquist number that the pedestal collapse is limited to the edge region and the edge localized mode (ELM) size is about 5%-10% of the pedestal stored energy. This is consistent with many observations of large ELMs.

A 130 point Nd:YAG Thomson scattering diagnostic on MAST

A Thomson scattering diagnostic designed to measure both edge and core physics has been implemented on MAST. The system uses eight Nd:YAG lasers, each with a repetition rate of 30 Hz. The relative and absolute timing of the lasers may be set arbitrarily to produce fast bursts of measurements to suit the time evolution of the physics being studied. The scattered light is collected at F/6 by a 100 kg six element lens system with an aperture stop of 290 mm. The collected light is then transferred to 130 polychromators by 130 independent fiber bundles. The data acquisition and processing are based on a distributed computer system of dual core processors embedded in 26 chassis. Each chassis is standalone and performs data acquisition and processing for five polychromators. This system allows data to be available quickly after the MAST shot and has potential for real-time operations.

THE METABOLISM OF TISSUE CULTURES : I. PRELIMINARY STUDIES ON CHICK EMBRYO

1. The metabolism of chick embryo tissues has been followed by analysis of the culture media after various periods of incubation in roller bottles. 2. The initial rate of glucose utilization is increased by increasing glucose in the medium from 100 to 500 mg. per cent. Total glucose used can be increased in the same way or by daily addition of small amounts. Glucose is used in greatest amount when the medium containing 100 mg. per cent is replaced daily. 3. Although glucose consumption appears necessary for survival of cultures it may be used at a rate far in excess of that required for life and maximal growth. Complete blocking of mitosis by colchicine does not alter the rate of glucose utilization. 4. Proteolytic activity of the cultures is shown by an increase in the amino nitrogen of the peptone medium after incubation with tissue. 5. Utilization of nitrogen from an amino acid medium is shown by a decrease in the amino nitrogen of this medium. Cells obtaining their nitrogen from amino acids proliferate as rapidly as those grown in a medium identical except for the substitution of peptone, but the cell type is markedly different, in that embryo muscle forms cells resembling regenerating adult muscle. 6. Lactic acid was formed in both the presence and absence of glucose. Its formation increased with increased glucose utilization. There is some evidence that lactate may be utilized, and that it favors growth in the absence of glucose. 7. Added pyruvate was rapidly metabolized by the tissues. It, too, favors growth slightly in the absence of glucose.

The outcome of five years' implementation of maternal serum screening for Down's syndrome comparing actual age risks and mode of delivery

In this paper 13 613 triple test results from the period 1992- 1997 were analysed. The probability of receiving a high risk result for Down's syndrome from a serum screen, related to the patient's age, was calculated. The modes of delivery of the patients receiving a high risk result were also compared with the rest of the population. The probability of receiving a high risk result increased from 1.2% at 25 years of age to 43.9% at 40 years of age. There was a decrease in the likelihood of having operative intervention at delivery amongst the high risk group but this did not reach statistical significance. This highlights the need for accurate information in risk and probability when counselling a patient undergoing serum screening. Patient's anxiety relating to mode of delivery may also be alleviated by knowing they have no greater risk of operative delivery.

Does long term therapy with lansoprazole slow progression of oesophageal involvement in systemic sclerosis?

OBJECTIVES

Oesophageal scintigraphy is an effective, non-invasive screening test to detect oesophageal dysmotility and reflux. Our objective was to assess the long term effect of lansoprazole therapy on gastroesophageal dysmotility in systemic sclerosis (SSc).

METHODS

24 SSc patients were randomised to receive either lansoprazole 30 mg or placebo for 12 months. Gastroesophageal motility was assessed by scintigraphy at baseline, after 6 months and after 12 months. Symptoms were evaluated by self-reported gastrointestinal questionnaire.

RESULTS

Of 21 patients starting treatment, 17 (81%) completed the first 6 months and 13 (62%) completed the study. 3 patients from each group were withdrawn due to adverse events. As expected, lansoprazole appeared to decrease frequency of gastroesophageal symptoms in the first 6 months of treatment, but long term benefit was not evident. Scintigraphy showed worsening oesophageal dysmotility in SSc patients irrespective of lansoprazole treatment. In addition, early signs of dysmotility were found in asymptomatic patients. We found no correlation of scintigraphy findings with symptoms of gastroesophageal dysmotility.

CONCLUSION

Although lansoprazole 30 mg daily appears to suppress SSc-related gastroesophageal symptoms in the short term, benefit was not sustained at 12 months, and there was no evidence that progression of gastroesophageal motility was prevented. Scintigraphy findings did not correlate with symptoms of dysphagia.

An open-label pilot study of infliximab therapy in diffuse cutaneous systemic sclerosis

AIM

The safety and potential efficacy of a chimaeric anti-tumour necrosis factor alpha monoclonal antibody (infliximab) were examined in diffuse cutaneous systemic sclerosis (dcSSc).

METHODS

A 26-week open-label pilot study in which 16 cases of dcSSc received five infusions of infliximab (5 mg/kg). Clinical assessment included skin sclerosis score, scleroderma health assessment questionnaire, self-reported functional score and physician global visual analogue scale. Collagen turnover, skin biopsy analysis and full safety evaluation were performed.

RESULTS

There was no significant change in skin score at 26 weeks but a trend for lower modified Rodnan skin score at 22 weeks (OR 17, 95% CI 6 to 46) compared with peak value (OR 29, 95% CI 11 to 44; p = 0.10). Serum aminoterminal propeptide of type III collagen level was significantly lower at week 26 compared with baseline (p = 0.03). Secretion of type I collagen by dermal fibroblasts was reduced at 26 weeks compared with baseline (p = 0.02). There were no deaths during the study and no suspected unexpected serious adverse reactions. 21 serious adverse events (AE) occurred in seven subjects, mostly attributable to dcSSc. 127 distinct AE occurred in 16 subjects. Of these, 19 AE (15%) were probably or definitely related to infliximab treatment. Eight (50%) patients prematurely discontinued infliximab. Anti-infliximab antibodies developed during the study in five subjects and were significantly associated with suspected infusion reactions (p = 0.025).

CONCLUSION

In dcSSc infliximab did not show clear benefit at 26 weeks but was associated with clinical stabilisation and a fall in two laboratory markers of collagen synthesis. The frequency of suspected infusion reactions may warrant additional immunosuppression in any future studies in systemic sclerosis.

Capecitabine-associated coronary vasospasm: a case report

Capecitabine (Xeloda) is an oral 5-fluorouracil pro-drug used in the treatment of two of the commonest cancers: breast and colorectal. This report concerns a 43-year-old woman with metastatic cancer of the sigmoid colon who developed cardiac chest pain 5 days after starting capecitabine therapy. Capecitabine-induced cardiac symptoms have previously been reported but infrequently. In the main they have documented pain and electrocardiogram (ECG) changes associated with exercise. This case report is of a patient with minimal cardiac risk factors, who had ischaemic cardiac pain with widespread ECG changes at rest that resolved with a nitrate infusion. Coronary vasospasm is proposed as the probable mechanism for the cardiac ischaemia and dramatic ECG changes. Capecitabine is now in widespread use and so physicians will encounter an increasing number of patients using this therapy. In the light of this, it is important that doctors in emergency and acute medicine are aware of its treatable cardiac side effects.