Antiviral drugs prolong survival in murine recessive dystrophic epidermolysis bullosa

Recessive dystrophic epidermolysis bullosa (RDEB) is a rare inherited skin disease characterized by defects in type VII collagen leading to a range of fibrotic pathologies resulting from skin fragility, aberrant wound healing, and altered dermal fibroblast physiology. Using a novel in vitro model of fibrosis based on endogenously produced extracellular matrix, we screened an FDA-approved compound library and identified antivirals as a class of drug not previously associated with anti-fibrotic action. Preclinical validation of our lead hit, daclatasvir, in a mouse model of RDEB demonstrated significant improvement in fibrosis as well as overall quality of life with increased survival, weight gain and activity, and a decrease in pruritus-induced hair loss. Immunohistochemical assessment of daclatasvir-treated RDEB mouse skin showed a reduction in fibrotic markers, which was supported by in vitro data demonstrating TGFβ pathway targeting and a reduction of total collagen retained in the extracellular matrix. Our data support the clinical development of antivirals for the treatment of patients with RDEB and potentially other fibrotic diseases.

Trametinib-Induced Epidermal Thinning Accelerates a Mouse Model of Junctional Epidermolysis Bullosa

Junctional epidermolysis bullosa (JEB) patients experience skin and epithelial fragility due to a pathological deficiency in genes associated with epidermal adhesion. Disease severity ranges from post-natal lethality to localized skin involvement with persistent blistering followed by granulation tissue formation and atrophic scarring. We evaluated the potential of utilizing Trametinib, an MEK inhibitor previously shown to target fibrosis, with and without the documented EB-anti-fibrotic Losartan for reducing disease severity in a mouse model of JEB; Lamc2^jeb mice. We found that Trametinib treatment accelerated disease onset and decreased epidermal thickness, which was in large part ameliorated by Losartan treatment. Interestingly, a range of disease severity was observed in Trametinib-treated animals that tracked with epidermal thickness; those animals grouped with higher disease severity had thinner epidermis. To examine if the difference in severity was related to inflammation, we conducted immunohistochemistry for the immune cell markers CD3, CD4, CD8, and CD45 as well as the fibrotic marker αSMA in mouse ears. We used a positive pixel algorithm to analyze the resulting images and demonstrated that Trametinib caused a non-significant reduction in CD4 expression that inversely tracked with increased fibrotic severity. With the addition of Losartan to Trametinib, CD4 expression was similar to control. Together, these data suggest that Trametinib causes a reduction in both epidermal proliferation and immune cell infiltration/proliferation, with concurrent acceleration of skin fragility, while Losartan counteracts Trametinib's adverse effects in a mouse model of JEB.

Implementation of self-monitoring of blood glucose for patients with insulin-dependent diabetes at a rural non-communicable disease clinic in Neno, Malawi

BACKGROUND

Self-monitoring of blood glucose (SMBG) is a widely accepted standard of practice for management of insulin-dependentdiabetes, yet is largely unavailable in rural sub-Saharan Africa (SSA). This prospective cohort study is the first known report ofimplementation of SMBG in a rural, low-income country setting.

OBJECTIVES

To evaluate adherence and change in clinical outcomes with SMBG implementation at two rural hospitals in Neno, Malawi.

METHODS

Forty-eight patients with type 1 and insulin-dependent type 2 diabetes were trained to use glucometers and logbooks. Participantsmonitored preprandial glucose daily at rotating times and overnight glucose once a week. Healthcare providers were trained to evaluateglucose trends, and adjusted insulin regimens based on results. Adherence was measured as the frequency with which patients checked anddocumented blood glucose at prescribed times, while clinical changes were measured by change in glycated haemoglobin (HbA1c) over a6-month period.

RESULTS

Participants brought their glucometers and logbooks to the clinic 95 - 100% of the time. Adherence with measuring glucose valuesand recording them in logbooks eight times a week was high (mean (standard deviation) 69.4% (15.7) and 69.0% (16.6), respectively). MeanHbA1c decreased from 9.0% (75 mmol/mol) at enrolment to 7.8% (62 mmol/mol) at 6 months (mean difference 1.2% (95% confidenceinterval (CI) 0.6 - 2.0; p=0.0005). The difference was greater for type 1 diabetes (1.6%; 95% CI 0.6 - 2.7; p=0.0031) than for type 2 diabetes(0.9%; 95% CI 0.1 - 1.9; p=0.0630). There was no documented increase in hypoglycaemic events, and no hospitalisations or deaths occurred.

CONCLUSION

SMBG is feasible for patients with insulin-dependent diabetes in a rural SSA population, and may be associated with improvedHbA1c levels. Despite common misconceptions, all patients, regardless of education level, can benefit from SMBG. Further research onlong-term retention of SMBG activities and the benefits of increasing frequency of monitoring is warranted.

The NOGO receptor NgR2, a novel αVβ3 integrin effector, induces neuroendocrine differentiation in prostate cancer

Androgen deprivation therapies aimed to target prostate cancer (PrCa) are only partially successful given the occurrence of neuroendocrine PrCa (NEPrCa), a highly aggressive and highly metastatic form of PrCa, for which there is no effective therapeutic approach. Our group has demonstrated that while absent in prostate adenocarcinoma, the αVβ3 integrin expression is increased during PrCa progression toward NEPrCa. Here, we show a novel pathway activated by αVβ3 that promotes NE differentiation (NED). This novel pathway requires the expression of a GPI-linked surface molecule, NgR2, also known as Nogo-66 receptor homolog 1. We show here that NgR2 is upregulated by αVβ3, to which it associates; we also show that it promotes NED and anchorage-independent growth, as well as a motile phenotype of PrCa cells. Given our observations that high levels of αVβ3 and, as shown here, of NgR2 are detected in human and mouse NEPrCa, our findings appear to be highly relevant to this aggressive and metastatic subtype of PrCa. This study is novel because NgR2 role has only minimally been investigated in cancer and has instead predominantly been analyzed in neurons. These data thus pave new avenues toward a comprehensive mechanistic understanding of integrin-directed signaling during PrCa progression toward a NE phenotype.

Outcomes of decentralizing hypertension care from district hospitals to health centers in Rwanda, 2013-2014

Setting

Three district hospitals (DHs) and seven health centers (HCs) in rural Rwanda.

Objective

To describe follow-up and treatment outcomes in stage 1 and 2 hypertension patients receiving care at HCs closer to home in comparison to patients receiving care at DHs further from home.

Design

A retrospective descriptive cohort study using routinely collected data involving adult patients aged ⩾18 years in care at chronic non-communicable disease clinics and receiving treatment for hypertension at DH and HC between 1 January 2013 and 30 June 2014.

Results

Of 162 patients included in the analysis, 36.4% were from HCs. Patients at DHs travelled significantly further to receive care (10.4 km vs. 2.9 km for HCs, P < 0.01). Odds of being retained were significantly lower among DH patients when not adjusting for distance (OR 0.11, P = 0.01). The retention effect was consistent but no longer significant when adjusting for distance (OR 0.18, P = 0.10). For those retained, there was no significant difference in achieving blood pressure targets between the DHs and HCs.

Conclusion

By removing the distance barrier, decentralizing hypertension management to HCs may improve long-term patient retention and could provide similar hypertension outcomes as DHs.

Closing the gap: decentralising mental health care to primary care centres in one rural district of Rwanda

Setting: Programmes that integrate mental health care into primary care settings could reduce the global burden of mental disorders by increasing treatment availability in resource-limited settings, including Rwanda. Objective: We describe patient demographics, service use and retention of patients in care at health centres (HC) participating in an innovative primary care integration programme, compared to patients using existing district hospital-based specialised out-patient care. Design: This was a retrospective cohort study using routinely collected data from six health centres and one district hospital from October 2014 to March 2015. Results: Of 709 patients, 607 were cared for at HCs; HCs accounted for 88% of the total visits for mental disorders. Patients with psychosis used HC services more frequently, while patients with affective disorders were seen more frequently at the district hospital. Of the 68% of patients who returned to care within 90 days of their first visit, 76% had a third visit within a further 90 days. There were no significant differences in follow-up rates between clinical settings. Conclusion: This study suggests that a programme of mentorship for primary care nurses can facilitate the decentralisation of out-patient mental health care from specialised district hospital mental health services to HCs in rural Rwanda.

Public health costs for tuberculosis suspects in Wake County, North Carolina, United States

SETTING

As the incidence of tuberculosis (TB) declines in high-income countries, resources to control TB are also declining. A portion of these resources are utilized for the evaluation and treatment of persons initially suspected of, but who do not actually have, TB (TB suspects).

OBJECTIVE

To describe the cost of TB suspects to public health departments, and determine whether part of this cost can be averted using improved diagnostic tools.

DESIGN

We evaluated resource utilization for all TB suspects as well as a random sample of TB cases managed at the Wake County public health clinic during 2008-2010. The proportion of total health department costs attributable to TB suspects was estimated. A sensitivity analysis assessed the potential impact of a rapid, accurate diagnostic test to avert suspect-associated costs.

RESULTS

Of 135 patients evaluated for TB, 36 (27%) were suspects, accounting for 14% (US5,885) of the total estimated costs for managing all patients. A perfect diagnostic test with a 3-day turnaround would have averted US27,975 (53%) of the costs attributable to suspects.

CONCLUSION

A substantial proportion of public health resources is utilized to manage persons whose final diagnosis is not TB. Efficient implementation of novel rapid tests could avert substantial public health costs.

Effect of pre-exposure to sevoflurane on the bispectral index in women undergoing Caesarean delivery under general anaesthesia

BACKGROUND

Patients undergoing Caesarean delivery under inhalation anaesthesia are at a high risk of awareness, especially in the period before delivery. We assessed the effects of pre-exposure to sevoflurane on the bispectral index (BIS) in the interval before delivery.

METHODS

Sixty-four patients undergoing elective Caesarean delivery were randomly assigned to receive 1.0-1.1 vol% (control 1) or 1.2-1.3 vol% (control 2) end-tidal sevoflurane, or the same concentrations of end-tidal sevoflurane combined with pre-exposure to 1 vol% sevoflurane for the last 1 min of the preoxygenation period (the preSevo 1 and preSevo 2 groups, respectively). We assessed BIS values, arterial pressure, and heart rate at the time of induction; before intubation; and upon skin incision, uterine incision, and delivery. We also determined the maternal incidence of intraoperative awareness and the neonatal Apgar scores, and conducted umbilical blood gas analysis.

RESULTS

At skin incision, BIS values were significantly lower in the preSevo 1 group than in the control 1 group [50 (13) vs 72 (8), P<0.001] and in the preSevo 2 group than in the control 2 group [44 (11) vs 67 (10), P<0.001]. The mean BIS values in the preSevo 1 and 2 groups were maintained below 60 in the period before delivery. No other parameter differed among groups, and no patient exhibited intraoperative awareness.

CONCLUSIONS

Pre-exposure to low concentrations of sevoflurane reduced BIS values in the interval before delivery, suggesting that this approach may reduce the risk of maternal awareness. Clinical Research Information Service (code KCT0000069, http://cris.cdc.go.kr).

Estimation of teeth-to-vallecula distance for prediction of optimal oropharyngeal airway length in young children

BACKGROUND

Estimation of teeth-to-vallecula distance would facilitate the selection of properly sized oropharyngeal airways in young children. The aims of the present study were to measure the teeth-to-vallecula distance and to create an algorithm to predict this distance based on anatomical landmarks and patient characteristics in children.

METHODS

Two hundred children, aged 1-9 yr, undergoing elective surgery were investigated. After induction of general anaesthesia, the distance from the teeth to the vallecula was measured using a laryngoscope with a straight blade. After intubation, the distances from the mouth angle to the mandible angle and the tragus of the ear were measured with a tape measure.

RESULTS

The teeth-to-vallecula distance was significantly correlated with the age, weight, height, and external measurements (P<0.001). By stepwise multiple linear regression analysis, a formula was obtained for the teeth-to-vallecula distance (cm) = 3.998 + 0.017 × age (months)+the mouth-to-mandible distance × 0.286 with a high coefficient of determination (r²=0.764).

CONCLUSIONS

The teeth-to-vallecula distance can be predicted using the age and the mouth-to-mandible distance in young children.

Torsades de pointes triggered by severe diastolic hypotension with low hematocrit in the neohepatic stage of liver transplantation: a case report

We have described herein a 39-year-old male patient with hepatitis B virus-related cirrhosis (Child class C), showing a prolonged corrected QT interval, who developed torsades de pointes (TdP) in the neohepatic stage of liver transplantation (LT). There was no arrhythmia in the pre-anhepatic and anhepatic stages. Multiple premature ventricular complexes, ventricular tachycardia, and TdP suddenly developed at 16 minutes after graft reperfusion without any prodromal arrhythmia; they persisted for 118 seconds. Laboratory tests showed that serum potassium, calcium, and magnesium concentrations of 4.7 mmol/L, 1.05 mmol/L, and 1.85 mg/dL, respectively were within normal ranges. Likely causative factors for TdP in this patient included a prolonged corrected QT interval (553 msec), a low hematocrit (21%), and a low arterial blood pressure (systolic blood pressure, 80-90 mm Hg; diastolic blood pressure; 20-26 mm Hg) in the neohepatic stage. This case demonstrated the importance of optimal maintenance of coronary perfusion, with an adequate hematocrit level and electrolyte concentrations, to prevent the development of TdP in cirrhotic patients with a prolonged corrected QT interval during LT.

The interaction between intrathecal neostigmine and GABA receptor agonists in rats with nerve ligation Injury

Nerve ligation injury may produce a pain syndrome that includes tactile allodynia. Reversal effects on tactile allodynia have been demonstrated after the intrathecal administration of gamma-aminobutyric acid (GABA) receptor agonists or cholinesterase inhibitors in rats. We examined the drug interactions between neostigmine and muscimol or baclofen in a rat model of nerve ligation injury. Rats were prepared with tight ligation of the left L5-6 spinal nerves and chronic intrathecal catheter implantation. Tactile allodynia was measured by applying von Frey filaments ipsilateral to the lesioned hindpaw. Thresholds for paw withdrawal were assessed. Neostigmine (0.3-10 microg), muscimol (0.1-10 microg), and baclofen (0.1-3.0 microg) were administered to obtain the dose-response curve and the 50% effective dose (ED(50)). Fractions of ED(50) values were administered intrathecally to establish the ED(50)s of drug combinations (neostigmine-muscimol and neostigmine-baclofen). The drug interactions were performed. Intrathecal neostigmine, muscimol, baclofen, and their combinations produced a dose-dependent increase in withdrawal threshold of the lesioned hindpaw. Both analyses revealed a synergistic interaction for the neostigmine-muscimol combination, whereas the effect of the neostigmine-baclofen combination was additive. These results suggest that the activation of both muscarinic and GABA(A) receptors is required for synergistic interaction.

IMPLICATIONS

This study indicates that drug interaction is synergistic for the neostigmine-muscimol combination, whereas the effect of the neostigmine-baclofen combination is additive. In a rat model of nerve ligation injury, neostigmine, muscimol, baclofen, and their combinations provide an antagonism on touch-evoked allodynia at the spinal level.

Anti-fibrotic effects of a hot-water extract from Salvia miltiorrhiza roots on liver fibrosis induced by biliary obstruction in rats

The anti-fibrotic effects of a hot-water extract form the traditional Chinese medicinal herb Salvia miltiorrhiza (Labiatae) on liver fibrosis induced by biliary obstruction was studied in rats. Liver fibrosis was induced in male Sprague-Dawley rats by bile duct ligation and scission (BDL). After surgery, the hot-water extract of S. miltiorrhiza roots (100 mg kg(-1), p.o.) was administered daily for 28 days. The concentrations of aspartate transaminase, alanine transaminase, alkaline phosphatase, total bilirubin and total cholesterol in serum and hydroxyproline and malondialdehyde contents in liver were significantly increased in BDL rats. Treatment with the extract of S. miltiorrhiza significantly reduced (P < 0.01) the serum aspartate transaminase, alanine transaminase, alkaline phosphatase, and total cholesterol concentrations in BDL rats. The liver hydroxyproline content in BDL rats treated with extract was also reduced to 68% of that in BDL control rats (P < 0.01). The liver malondialdehyde content in BDL rats treated with the extract was also reduced to 47% of that in BDL control rats (P < 0.01). The morphological characteristics of fibrotic livers were improved in BDL rats treated with extract. Immunohistochemical examination of fibrotic liver showed that the extract of S. miltiorrhiza markedly reduced protein expression of alpha-smooth muscle cell-like actin, which indicates that hepatic stellate cell activation was inhibited during liver fibrosis development. The results indicate that the hot-water extract of S. miltiorrhiza roots inhibits fibrosis and lipid peroxidation in rats with liver fibrosis induced by biliary obstruction.

Effect of tetrandrine on experimental hepatic fibrosis induced by bile duct ligation and scission in rats

Tetrandrine, an alkaloid isolated from the Chinese medicinal herb Stephania tetrandra, has been shown to elicit antifibrotic effects in various cell types. In the present study, the effect of tetrandrine on liver fibrosis was investigated by using bile duct ligation and scission in rats as a model of hepatic fibrosis. Treatment with tetrandrine in fibrotic rats reduced serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase levels to 72%, 52% and 51% that of controls at 10 mg/kg/day, respectively. Liver hydroxyproline contents in tetrandrine-treated rats with bile duct ligation and scission were also reduced to 65% of that of control rats with bile duct ligation and scission at 10 mg/kg/day. The morphological characteristics of fibrotic liver, which appeared in control bile duct ligation and scission group, were improved in tetrandrine-treated bile duct ligation and scission group. We also examined the effect of tetrandrine on cultured rat hepatic stellate cells, which plays an important role in the pathogenesis of hepatic fibrosis, activation to investigate whether it could act mainly by direct action on rat hepatic fibroblastic cells. In cultured rat hepatic stellate cells, tetrandrine reduced DNA synthesis to 57% of control hepatic stellate cells at 10 microg/ml without affecting cell viability. Smooth muscle-alpha-actin expression, the phenotypic marker of activated hepatic stellate cells, was also decreased. We conclude that tetrandrine has an antifibrotic effect on liver fibrosis in rats induced by bile duct ligation and scission, indicating that it might exert a direct effect on rat hepatic stellate cells.

Antifibrotic effect of Stephania tetrandra on experimental liver fibrosis induced by bile duct ligation and scission in rats

We examined the antifibrotic effect of a methanol extract from Stephania tetrandra (ST) on experimental liver fibrosis. Liver fibrosis was induced by bile duct ligation and scission (BDL/S) in rats. In BDL/S rats, activity levels of aspartate transaminase (AST), alanine transaminse (ALT), alkaline phosphatase (ALP), concentration of total bilirubin in serum, and hydroxyproline content of the liver were significantly increased. The ST treatment (either 100 mg/kg/day or 200 mg/kg/day, p.o. for 4 weeks) in BDL/S rats reduced the serum AST, ALT and ALP activity levels significantly (p< 0.01). Similarly, when compared to the control group, the concentration of hydroxyproline in the livers of the BDL/S rats treated with 100mg or 200mg ST treated rats decreased by 40% and 33% respectively, when compared to the BDL/S control group (p<0.01). The morphological characteristics of fibrotic liver that were observed in the BDL/S control group, improved in the ST treated BDL/S group. In the fibrotic liver of BDL/S rats treated with ST, a marked reduction in the numbers of alpha smooth muscle cell actin positive stellate cells was observed. These results indicate that doses of either 100 or 200 mg/kg/day of methanol extract from S. tetrandra, had an antifibrotic effect in rats with liver fibrosis induced by bile duct ligation and scission.

Cloning and expression of a cysteine proteinase gene from Paragonimus westermani adult worms

A gene encoding a cysteine proteinase from Paragonimus westermani has been cloned and expressed in Escherichia coli. The cysteine proteinase cDNA fragment was amplified by reverse transcription-polymerase chain reaction (RT-PCR) using degenerate oligonucleotide primers derived from the conserved active site of the cysteine proteinase. The 5' and 3' regions of the gene were amplified using a PCR technique for the rapid amplification of cDNA ends. The cloned gene has an open reading frame of 687 bp and deduced amino acid sequence of 229. Sequence analysis and alignment showed significant homologies with the eukaryotic cysteine proteinases and conservation of the Cys, His, and Asp residues that form a catalytic triad. Analysis of the expressed protein on sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the molecular weight of the protein was approximately 28.5 kDa. The expressed protein reacted with the sera of patients with paragonimiasis but not with the sera of fascioliasis and clonorchiasis. These results suggest that the expressed protein may be valuable as a specific diagnostic material for the immunodiagnosis of paragonimiasis.

An analysis of drug interaction between morphine and neostigmine in rats with nerve-ligation injury

Intrathecal neostigmine reverses mechanical allodynia in humans and animals. The efficacy of morphine in a neuropathic pain state is still controversial. This study examines the antiallodynic interaction between morphine and neostigmine in a rat model of neuropathic pain. Rats were prepared with tight ligation of left L5-6 (fifth and sixth lumbar) spinal nerves and chronic intrathecal catheter implantation. Mechanical allodynia was measured by using application of von Frey hairs to the left hindpaw. Morphine (1, 3, 10, and 30 microg) and neostigmine (0.3, 1, 3, and 10 microg) were administered intrathecally to obtain the dose-response curves and the 50% effective dose (ED(50)) for each drug. ED(50) values and fractions of the ED(50) values (1/2, 1/4, and 1/8) were administered intrathecally in an equal dose ratio to establish the ED(50). Isobolographic and fractional analyses for the drug interaction were performed. Intrathecal morphine produced a moderate antagonism of the tactile allodynia. A morphine-neostigmine combination produced a dose-dependent increase in withdrawal threshold of the lesioned hind paw with reduced side effects. Both analyses revealed a synergistic interaction after the coadministration of morphine and neostigmine. These experiments suggest that the antiallodynic action of a morphine-neostigmine combination is synergistic at the spinal level.

IMPLICATIONS

This study indicates that, by using both isobolographic and fractional analyses, the antiallodynic effect of intrathecal morphine and neostigmine is synergistic when coadministered intrathecally. In a rat model of neuropathic pain, the intrathecal morphine produced a moderate antagonism on touch-evoked allodynia at the spinal level.

The antiallodynic effects of intrathecal cholinesterase inhibitors in a rat model of neuropathic pain

BACKGROUND

This study determined the effect of intrathecally administered cholinesterase inhibitors, edrophonium and neostigmine, on nerve injury-induced, touch-evoked allodynia and identified the pharmacologic characteristics of this action.

METHODS

Rats were prepared with tight ligation of the left L5 and L6 spinal nerves and with lumbar intrathecal catheters fitted for long-term monitoring. Edrophonium (3, 10, 30, or 100 microg) or neostigmine (0.3, 1, 3, or 10 microg) was administered intrathecally. Tactile allodynia and motor weakness were assessed. To evaluate the pharmacologic characteristics of the activity, a muscarinic receptor antagonist or a nicotinic receptor antagonist was administered intrathecally before edrophonium or neostigmine was injected. To compare the action of subtype antagonists, the M1 muscarinic receptor antagonist pirenzepine, the M2 antagonist methoctramine, the M3 antagonist 4-DAMP (diphenylacetoxy-N-methypiperidine), and the M4 antagonist tropicamide were administered intrathecally before cholinesterase inhibitors were injected.

RESULTS

Intrathecal edrophonium or neostigmine produced a dose-dependent antagonism of the touch-evoked allodynia. Neostigmine resulted in a moderate effect on motor weakness at doses of 3 and 10 microg. Pretreatment with intrathecal atropine but not mecamylamine yielded a complete antagonism of the effects of the cholinesterase inhibitors. In addition, antiallodynia produced by edrophonium (100 microg) was reversed by pretreatment with methoctramine, 4-DAMP, tropicamide, and pirenzepine. In the neostigmine (10 microg) group, only the M1 antagonist pirenzepine had a moderate effect on reversal of increased allodynic threshold.

CONCLUSIONS

These experiments suggest that intrathecal edrophonium or neostigmine produces an antagonism on touch-evoked allodynia at the spinal level in a rat model of neuropathic pain and that the antiallodynic action of cholinesterase inhibitors is probably mediated by a spinal muscarinic system, especially at the M1 receptor subtype.

Antiplatelet and antithrombotic effects of a combination of ticlopidine and ginkgo biloba ext (EGb 761)

The antiplatelet and antithrombotic effects of the oral combination treatment of ticlopidine and Ginkgo biloba extract (EGb 761) were studied in normal and thrombosis-induced rats. The ex vivo inhibitory effect on ADP-induced platelet aggregation of a small dose of ticlopidine (50 mg/kg/day) in combination with EGb 761 (40 mg/kg/day) was comparable to a larger dose of only ticlopidine (200 mg/kg/day). Bleeding time was also prolonged by 150%. Thrombus weight was also consistently decreased by a combination of ticlopidine and EGb 761 in an arterio-venous shunt model at two doses of ticlopidine (50 mg/kg) plus EGb 761 (20 mg/kg) and ticlopidine (50 mg/kg) plus EGb 761 (40 mg/kg). A combinatory treatment in acute thrombosis model in mice also showed a higher recovery than a single treatment.

Occlusive and reperfused myocardial infarction: detection by using MR imaging with gadolinium polylysine enhancement

PURPOSE

To assess the capability of gadolinium polylysine-enhanced cardiac magnetic resonance (MR) imaging in depicting normal and ischemic myocardium during occlusion and reperfusion of the left anterior descending artery.

MATERIALS AND METHODS

Contrast-enhanced MR images were obtained in 18 cats during 90 minutes each of occlusion and reperfusion. The change in signal intensity (SI) was compared among normal myocardium and central and peripheral ischemic zones. Results were compared with those of 2,3,5-triphenyltetrazolium chloride staining.

RESULTS

During occlusion, the ischemic zone lacked enhancement while normal myocardium had gradual enhancement. During reperfusion, the ischemic zone had strong enhancement. In cats with large infarction, the central and peripheral ischemic zones had intermediate and high SI, respectively; in cats with focal or no infarction, the entire ischemic zone had high SI.

CONCLUSION

Occlusive and reperfused myocardial infarction can be detected at gadolinium polylysine-enhanced MR imaging by means of differential SI changes in normal myocardium and central and peripheral ischemic zones.