Allogeneic platelet-rich plasma for knee osteoarthritis in patients with primary immune thrombocytopenia: A randomized clinical trial

The treatment of painful KOA in adult patients with ITP has not been well studied yet. We conducted a prospective, double-blind, randomized, placebo-controlled trial to evaluate the efficacy of intra-articular allogeneic PRP injections on symptoms and joint structure in patients with KOA and ITP. 80 participants were randomly allocated in a 1:1 ratio to allogeneic PRP group or saline group. The primary outcome was the WOMAC total score at 12 months post-injection. The number of patients in each group who achieved MCID of primary outcome showed a statistically significant difference only at 3-month (27/39 vs. 5/39, p = 0.001) and 6-month (15/39 vs. 3/38, p = 0.032). The difference in WOMAC total score exceeded the MCID only at 3 month (mean difference of -15.1 [95% CI -20.7 to -9.5], p < 0.001). Results suggest that allogeneic PRP was superior to placebo only with respect to symptoms at 3-month of follow-up.

Incidence of deep venous thrombosis in patients with hemophilia undergoing bilateral simultaneous total knee arthroplasty: a retrospective cohort study

BACKGROUND

Hemophilic arthropathy usually affects the knees bilaterally. In order to reduce costs and improve rehabilitation, bilateral simultaneous total knee arthroplasty (TKA) can be performed. However, pharmacological prophylaxis for deep venous thrombosis (DVT) remains controversial in patients with severe hemophilia. The purpose of this study was to establish the incidence of DVT in severe hemophilia A patients undergoing bilateral simultaneous TKA without pharmacological thromboprophylaxis.

METHODS

Consecutive patients with severe hemophilia A undergoing bilateral simultaneous TKA at a single center between January 2015 and December 2020 were retrospectively reviewed. All patients received a modified coagulation factor substitution regimen. Tranexamic acid (TXA) was used for hemostasis in all patients during surgery. All patients followed a standardized postoperative protocol with routine mechanical thromboprophylaxis, and none received anticoagulation. D-dimer was measured preoperatively, on the day of the operation and on postoperative days 1, 7 and 14. Ultrasound (US) of the lower extremities was performed before (within 3 days of hospitalization) and after surgery (days 3 and 14) to detect asymptomatic DVT. Patients were followed up until 2 years after surgery for the development of symptomatic DVT or pulmonary embolism (PE).

RESULTS

38 male patients with severe hemophilia A underwent 76 simultaneous TKAs. Mean (± standard deviation) age at the time of operation was 41.7 (± 17.1) years. Overall, 47.3% of patients had D-dimer concentrations above the threshold 10 µg/mL on day 7 and 39.5% on day 14. However, none of the patients had DVT detected on postoperative US, nor developed symptomatic DVT or PE during the 2-year follow-up.

CONCLUSIONS

The risk of DVT in patients with severe hemophilia A after bilateral simultaneous TKA is relatively low, and routine pharmacological thromboprophylaxis may not be needed.

Recent advances of exosomes in soft tissue injuries in sports medicine: A critical review on biological and biomaterial applications

Sports medicine is generally associated with soft tissue injuries including muscle injuries, meniscus and ligament injuries, tendon ruptures, tendinopathy, rotator cuff tears, and tendon-bone healing during injuries. Tendon and ligament injuries are the most common sport injuries accounting for 30-40% of all injuries. Therapies for tendon injuries can be divided into surgical and non-surgical methods. Surgical methods mainly depend on the operative procedures, the surgeons and postoperative interventions. In non-surgical methods, cell therapy with stem cells and cell-free therapy with secretome of stem cell origin are current directions. Exosomes are the main paracrine factors of mesenchymal stem cells (MSCs) containing biological components such as proteins, nucleic acids and lipids. Compared with MSCs, MSC-exosomes (MSC-exos) possess the capacity to escape phagocytosis and achieve long-term circulation. In addition, the functions of exosomes from various cell sources in soft tissue injuries in sports medicine have been gradually revealed in recent years. Along with the biological and biomaterial advances in exosomes, exosomes can be designed as drug carriers with biomaterials and exosome research is providing promising contributions in cell biology. Exosomes with biomaterial have the potential of becoming one of the novel therapeutic modalities in regenerative researches. This review summarizes the derives of exosomes in soft tissue regeneration and focuses on the biological and biomaterial mechanism and advances in exosomal therapy in soft tissue injuries.

Inhibitor development according to concentrate in severe hemophilia: reporting on 1392 Previously Untreated Patients from Europe and Canada

Background

Clotting factor concentrates have been the mainstay of severe hemophilia treatment over the last 50 years. Differences in risk of neutralizing antibody (inhibitor) formation according to concentrate used remain clinically relevant.

Objectives

To assess inhibitor development according to type of clotting factor concentrate in previously untreated patients (PUPs) with severe hemophilia A and B.

Methods

The European Haemophilia Safety Surveillance (EUHASS) and Canadian Bleeding Disorders Registry (CBDR) have been monitoring adverse events overall and according to concentrate for 11 and 8 years, respectively. Inhibitors were reported quarterly, and PUPs completed 50 exposure days without inhibitor development annually. Cumulative inhibitor incidences and 95% confidence intervals (CIs) were compared without adjustment for other risk factors.

Results

Fifty-six European and 23 Canadian centers reported inhibitor development in 312 of 1219 (26%; CI, 23%-28%) PUPs with severe hemophilia A and 14 of 173 (8%; CI, 5%-13%) PUPs with severe hemophilia B. Inhibitor development was lower on plasma-derived factor (F)VIII (pdFVIII, 20%; CI, 14%-26%) than on standard half-life recombinant FVIII (SHL-rFVIII, 27%; CI, 24%-30% and odds ratio, 0.67; CI, 0.45%-0.98%; P = .04). Extended half-life recombinant FVIII (EHL-rFVIII, 22%; CI, 12%-36%) showed an intermediate inhibitor rate, while inhibitor rates for Advate (26%; CI, 22%-31%) and Kogenate/Helixate (30%; CI, 24%-36%) overlapped. For other SHL-rFVIII concentrates, inhibitor rates varied from 3% to 43%. Inhibitor development was similar for pdFIX (11%; CI, 3%-25%), SHL-rFIX (8%; CI, 3%-15%), and EHL-rFIX (7%; CI, 1%-22%).

Conclusion

While confirming expected rates of inhibitors in PUPs, inhibitor development was lower in pdFVIII than in SHL-rFVIII. Preliminary data suggest variation in inhibitor development among different SHL-rFVIII and EHL-rFVIII concentrates.

Navigating through the haemostatic paradox in kidney failure: A practical overview

Chronic kidney disease (CKD) affects around 9.1% of humankind globally resulting in a significant health burden. Some of these individuals will also require renal replacement therapy with dialysis due to complete kidney failure. Patients with CKD are known to be at increased risk of both bleeding and thrombosis. Often it is very difficult to manage these yin and yang since both risks tend to co-exist. Clinically, very few studies have looked at the effects of antiplatelet agents and anticoagulants in this highly vulnerable subgroup of medical patients and evidence is very limited. This review attempts to explain the current state-of-the-art regarding the basic science of haemostasis in patients with end-stage kidney disease. We also try to transfer this knowledge into the clinics by looking at some common haemostasis challenges that are encountered in this cohort of patients and what evidence and guidance there is for their optimal management.

Long COVID syndrome: a case-control study

Background

Cardiovascular complications are rapidly emerging as a major threat in COVID-19 infection. Nonetheless, the mechanisms underlying the disproportionate effect of SARS-CoV-2 infection on patients with cardiovascular comorbidities remain incompletely understood.

Purpose

To assess whether COVID-19 infection has an adverse clinical outcome at medium-term follow-up.

Methods

A case-control study was performed. Cases were subjects who were diagnosed with COVID-19 infection following nasopharyhngeal swabbing. Controls were age- and gender-matched subjects who were not found to be infected with COVID-19 following swabbing and were negative on testing for COVID-19 IgG antibodies. All participants were submitted a standardised questionnaire regarding past medical history. Baseline blood investigations were taken including N-terminal pro–B-type natriuretic peptide (NT-proBNP) and troponin levels. High-sensitivity C-reactive protein (hsCRP) was taken as marker of inflammation and von Willebrand factor (vWF) was taken as marker of endothelial dysfunction.

Results

270 subjects were recruited, comprising 174 cases and 96 controls. Of the latter, 21 were found to be COVID-19 IgG positive and were excluded from the analysis. Hence, the study cohort comprised 174 cases and 75 controls. The mean age of the participants was 46.1±13.8 years. The median follow-up was of 173.5 days (IQR 129–193.25 days). There was no statistically significant difference in the baseline demographics between cases and controls with regards age, gender as well as cardiovascular risk factors and underlying medical conditions. Regarding symptomatology at follow-up, there was a statistically significant difference between the groups in deterioration in general condition (p<0.001), shortness of breath (SOB) (p=0.008), fatigue (p=0.044), arthralgia (p<0.001), abnormal taste (p<0.001) and anosmia (p<0.001), all being more frequent in subjects with prior COVID-19 infection. At follow-up, the blood investigations showed that only hsCRP was statistically significantly higher in the cases as compared to the controls (p=0.03, Figure 1). Correlation analysis consequently revealed a negative correlation in both troponin (p=0.013, r=−0.19) and vWF levels (p=0.026, r=−0.169) with time. Finally, the association between the cases experiencing dyspnoea and the blood investigations at follow-up was assessed. Multivariate analysis revealed that COVID-19 positive cases experiencing dyspnoea have significantly higher white cell count (WCC) (OR 1.22, 95% CI 1.02–1.46, p=0.029) and troponin levels (OR 1.15, 95% CI 1.02–1.29, p=0.015) and lower haemoglobin levels at follow-up (OR 0.66, 95% CI 0.5–0.86, p<0.002), Figure 2.

Conclusion

Patients previously infected with COVID-19 have persistent symptomatology at medium-term follow-up. The role of troponin, together with markers of inflammation and endothelial dysfunction at long-term follow-up merit further investigation.

Funding Acknowledgement

Type of funding sources: None.

The Charcot Foot: An Emerging Public Health Problem for African Diabetes Patients

Background: Although the awareness, diagnosis, management of the complications associated with diabetes have improved in African countries over the past decade, surveillance activities in Tanzania and anecdotal reports from other African countries have suggested an increased prevalence of Charcot Neuroarthropathy (CN) over the past few years. Aim: To characterize the epidemiology and the clinical burden of CN in a large diabetes population in Tanzania, and to evaluate outcomes of persons with the condition. Methods: This was a prospective analytic cohort study conducted between January 2013 through December 2015. Following informed consent, patients were followed at the outpatient clinic. Detailed clinical assessments and documented presence of diabetic peripheral neuropathy (DPN), macrovascular disease and microvascular disease were recorded. Education and counseling were part of the follow-up program. Results: 3271 ulcerations were presented at the clinic during the 3-year study period. 571 (18%) met the case definition for CN; all patients had Type 2 diabetes. The prevalence for each of the years 2013, 2014, and 2015 was 19/1192 (1.6%), 209/1044 (20%), and 343/1035 (34%), respectively; the increases in the slope of the trendline was statistically significant (P < .001). Conclusion: The prevalence of CN is increasing in the Tanzanian diabetes patient population, and is strongly associated with neuropathy. CN can lead to severe deformity, disability, and amputation. Due to the risk of limb amputation, patients with diabetes must seek immediate care if signs or symptoms appear and avoid delay in seeking medical attention. Early diagnosis of CN by caregivers is extremely important for successful outcomes.

Superficial Tissue Swabs Versus Deep Tissue Samples in the Detection of Microbiological Profile of Infected Diabetic Foot Ulcerations

This study aimed to determine the most accurate microbiological test for the detection of micro-organisms in infected diabetic foot ulcerations in people living with type-2 Diabetes. For 20 eligible patients, a superficial tissue swab and a deep tissue sample were taken during a regular appointment at a Diabetes out-patient's Podiatry Clinic. Two specimens were collected from each wound for microbial culturing after debridement. Infected foot ulcerations were graded according to the Wagner's classification as per clinical protocol. This study found a significant difference [p = 0.028] between the two different samples. The deep tissue sample was found to be more accurate in identifying micro-organisms than the superficial swabs, although the latter is more widely used in clinical practice. Further studies are warranted to provide more evidence to clinicians on the best method to adopt when swabbing different types of diabetic foot ulcerations with different wound classification since, it is clearly still a matter of debate how to detect wound infection.

Peripheral vascular changes in the lower limbs following cocaine abuse

Background: Worldwide, substance use disorder is on the rise, especially amongst the young generation. Although cocaine-induced cardiovascular and cerebrovascular events are well documented, knowledge about the relationship of cocaine use and its effect on arterial perfusion in the lower limbs is scarce.Objective: This study sought to investigate the relationship between cocaine use and peripheral arterial disease.Methods: The study population comprised 30 subjects' dependent on cocaine, smoking and alcohol [Group A] and another 30 subjects dependent on smoking and alcohol only [Group B]. A comprehensive lower limb vascular assessment was conducted utilizing pulse palpation, Doppler spectral waveform analysis, Ankle brachial pressure index (ABPI) and Toe brachial pressure index (TBPI) to determine the arterial perfusion status in the lower limbs.Results: Group A had lower ABPIs and TBPIs than Group B suggesting poorer vascular perfusion in lower limbs. Furthermore, a larger percentage of Group A had monophasic/continuous waveforms of all three pedal pulses compared to Group B. Conversely there was a higher percentage in Group B with biphasic/triphasic waveforms compared to Group A implying better vascular perfusion.Conclusion: In this study, cocaine use was associated with diminished arterial perfusion of the lower limbs suggesting that cocaine use has the potential to increase the risk of peripheral arterial disease. Regular vascular foot screening is warranted if foot complications are to be avoided.

Diabetes foot screening: Challenges and future strategies

BACKGROUND

Healthcare options for people with diabetes is still not uniform both within and between countries. This is particularly evident for diabetic foot disease. The number of existing documents/guidelines, together with discrepancies which exist between different organizations or countries can lead to confusion for both practicing health care professionals and new countries or organizations who are in the process of developing local clinical guidelines. This study was aimed at exploring different stakeholder perspectives with a view to develop and introduce culturally competent foot screening guidelines.

METHODS

A phenomenological study which incorporated non-structured interviews with eleven local stakeholders and experts related to the field were conducted to explore interviewees' perspectives regarding foot screening guidelines in Malta.

FINDINGS

Qualitative analysis identified 3 key themes from the data highlighting barriers to the implementation of diabetes foot screening guidelines. These focused on organizational factors, healthcare professional factors and patient factors.

CONCLUSION

Current procedures related to diabetes foot screening has shortcomings. The findings of this study clearly highlight the need for change in current practices if effective diabetic foot screening is to be offered. Recommendations from this study are relevant to other countries especially those who share same cultures and practices. Making changes today and implementing them in the appropriate manner could make a world of difference in diabetes foot care.

Unusual case of primary pulmonary Hodgkin's lymphoma presenting with a continuous murmur

Systemic to pulmonary fistulas are an unusual entity, even more so in association with Hodgkin's lymphoma. We herein report a case of a 33-year-old woman that presented with an incidental lung lesion on a chest radiograph with an associated high-frequency continuous murmur over the lesion. The diagnosis of primary pulmonary Hodgkin's lymphoma, nodular sclerosis type, was obtained by a CT transthoracic biopsy. We achieved an excellent response after polychemotherapy with near-complete disappearance of the mass and a residual faint systolic murmur over the lesion.

The rarest aortic arch anomaly a case report of asymptomatic isolation of the subclavian artery

We present a rare case of isolated right subclavian artery arising from a right-sided patent arterial duct in a patient with DiGeorge syndrome, diagnosed on cardiac CT, along with potential complications and management approaches.

Alterations in coagulation following major liver resection

The international normalised ratio is frequently raised in patients who have undergone major liver resection, and is assumed to represent a potential bleeding risk. However, these patients have an increased risk of venous thromboembolic events, despite conventional coagulation tests indicating hypocoagulability. This prospective, observational study of patients undergoing major hepatic resection analysed the serial changes in coagulation in the early postoperative period. Thrombin generation parameters and viscoelastic tests of coagulation (thromboelastometry) remained within normal ranges throughout the study period. Levels of the procoagulant factors II, V, VII and X initially fell, but V and X returned to or exceeded normal range by postoperative day five. Levels of factor VIII and Von Willebrand factor were significantly elevated from postoperative day one (p < 0.01). Levels of the anticoagulants, protein C and antithrombin remained significantly depressed on postoperative day five (p = 0.01). Overall, the imbalance between pro- and anticoagulant factors suggested a prothrombotic environment in the early postoperative period.

Patients with liver cirrhosis suffer from primary haemostatic defects? Fact or fiction?

Patients with cirrhosis can have abnormalities in laboratory tests reflecting changes in primary haemostasis, including bleeding time, platelet function tests, markers of platelet activation, and platelet count. Such changes have been considered particularly relevant in the bleeding complications that occur in cirrhosis. However, several studies have shown that routine diagnostic tests, such as platelet count, bleeding time, PFA-100, thromboelastography are not clinically useful to stratify bleeding risk in patients with cirrhosis. Moreover, treatments used to increase platelet count or to modulate platelet function could potentially do harm. Consequently the optimal management of bleeding complications is still a matter of discussion. Moreover, in the last two decades there has been an increased recognition that not only bleeding but also thrombosis complicates the clinical course of cirrhosis. Thus, we performed a literature search looking at publications studying both qualitative and quantitative aspects of platelet function to verify which primary haemostasis defects occur in cirrhosis. In addition, we evaluated the contribution of qualitative and quantitative aspects of platelet function to the clinical outcome in cirrhosis and their therapeutic management according to the data available in the literature. From the detailed analysis of the literature, it appears clear that primary haemostasis may not be defective in cirrhosis, and a low platelet count should not necessarily be considered as an automatic index of an increased risk of bleeding. Conversely, caution should be observed in patients with severe thrombocytopenia where its correction is advised if bleeding occurs and before invasive diagnostic and therapeutic procedures.

Enhanced thrombin generation in patients with cirrhosis-induced coagulopathy

BACKGROUND

Prothrombin time (PT) and the international normalized ratio (INR) are still routinely measured in patients with liver cirrhosis to 'assess' their bleeding risk despite the lack of correlation with the two. Thrombin generation (TG) assays are global assays of coagulation that are showing promise in assessing bleeding and thrombosis risks.

AIM

To study the relationship between the INR and TG profiles in cirrhosis-induced coagulopathy.

METHODS

Seventy-three patients with cirrhosis were studied. All TG parameters were compared with those from a normal control group. Contact activation was prevented using corn trypsin inhibitor. TG was also assayed in the presence of Protac(®). The endogenous thrombin potential (ETP) ratio was derived by dividing the ETP with Protac® by the ETP without Protac®.

RESULTS

The INR (mean 1.7) did not correlate with the ETP and the velocity of TG (P > 0.05). There was no difference between the lag time and ETP of the two groups (P > 0.05). The velocity of TG was increased in cirrhosis (67.95 ± 34.8 vs. 45.05 ± 25.9 nM min⁻¹ ; P = 0.016) especially in patients with INRs between 1.21 and 2.0. Both the ETP with Protac(®) and the ETP ratio were increased in cirrhosis (mean 1074 ± 461.4 vs. 818 ± 357.9 nM min, P = 0.004 and 0.80 ± 0.21 vs. 0.44 ± 0.15, P ≤ 0.0001, respectively).

CONCLUSION

Despite a raised INR, TG parameters are consistent with a hypercoagulable profile in cirrhosis-related coagulopathy. This confirms that the PT or INR should not be used to assess bleeding risk in these patients, and other parameters, such as TG, need to be explored as clinical markers of coagulopathy.

Systematic review: portal vein thrombosis in cirrhosis

BACKGROUND

As current imaging techniques in cirrhosis allow detection of asymptomatic portal vein thrombosis during routine ultrasonography, more patients with cirrhosis are diagnosed with portal vein thrombosis. Although a consensus on noncirrhotic extra-hepatic portal vein thrombosis has been published, no such consensus exists for portal vein thrombosis with cirrhosis.

AIM

To perform a systematic review of nonmalignant portal vein thrombosis in cirrhosis in terms of prevalence, pathogenesis, diagnosis, clinical course and management.

METHODS

Studies were identified by a search strategy using MEDLINE and EMBASE.

RESULTS

Portal vein thrombosis is encountered in 10-25% of cirrhotics. In terms of pathophysiology, cirrhosis is no longer considered a hypocoagulable state; rather than a bleeding risk in cirrhosis, various clinical studies support a thrombotic potential. Clinical findings of portal vein thrombosis in cirrhosis vary from asymptomatic disease to a life-threatening condition at first presentation. Optimal management of portal vein thrombosis in cirrhosis is currently not addressed in any consensus publication. Treatment strategies most often include the use of anticoagulation, while thrombectomy and transjugular intrahepatic portosystemic shunts are considered second-line options.

CONCLUSIONS

Portal vein thrombosis in cirrhosis has many unresolved issues, which are often the critical problems clinicians encounter in their everyday practice. We propose a possible research agenda to address these unresolved issues.

Optimizing warfarin reversal--an ex vivo study

BACKGROUND

Warfarin reversal is a common clinical situation. This is commonly performed using vitamin K and, depending on the urgency, fresh frozen plasma (FFP), prothrombin complex concentrates (PCCs), or activated factor VII. Even though PCCs are widely used, the ideal dosing regimen is far from established.

OBJECTIVES

To verify differences in warfarin reversal patterns using FFP, recombinant FVIIa (rFVIIa), and PCC; and to test the hypothesis that supratherapeutic International Normalized Ratios (INRs) might not correlate with thrombin generation (TG) and identify the ideal concentrations of PCC required to reverse various INR thresholds.

METHODS

We studied the effects of FFP, rFVIIa and Beriplex P/N on the INR and TG, using the calibrated automated thrombography assay in ex vivo warfarinized plasma. Plasmas with different INRs were spiked with different concentrations of Beriplex P/N.

RESULTS

Beriplex P/N was the only agent that completely normalized TG and the INR. The endogenous thrombin potential (ETP) and the peak thrombin showed a significant negative correlation with all INRs. The ETP and velocity of TG reached a plateau at an INR of approximately 4.0. A concentration equivalent to a dose of 30 IU kg(-1) Beriplex P/N normalized the ETP, the INR, FII, FVII, FIX and FX of samples with INRs > or = 4.0. Higher doses resulted in hypercoagulable TG patterns. A concentration equivalent to a dose of 20 IU kg(-1) was sufficient to reverse warfarin at an INR range of 2.0-3.9, as judged by the same tests.

CONCLUSIONS

Warfarin reversal algorithms could be simplified with the adoption of this strategy utilizing two doses of PCC, depending on the INR of the patient. This would also lead to cost reductions and, possibly, a reduction in thrombotic risk.

Outbreak of norovirus infection in a nursing home for the elderly in Malta, November-December 2008

In norovirus outbreak in a nursing home in Malta in November and December 2008, 44 people were affected. 35 of 91 residents and nine of 44 employees were symptomatic. The overall attack rate among residents was 38.5% [corrected]. The outbreak lasted 17 days and the symptoms were mild.

Outbreak of norovirus infection in a nursing home for the elderly in Malta, November-December 2008

In norovirus outbreak in a nursing home in Malta in November and December 2008, 44 people were affected. 35 of 91 residents and nine of 44 employees were symptomatic. The overall attack rate among residents was 38.5%. The outbreak lasted 17 days and the symptoms were mild.

Management of surgical patients receiving anticoagulation and antiplatelet agents

BACKGROUND

Temporary interruption of long-term anticoagulation and antiplatelet therapy during surgical procedures exposes patients to thrombotic risk. Continuation of these agents, however, is associated with an increased risk of bleeding. Managing anticoagulation can be a particular challenge in the emergency setting.

METHODS

A literature review of published articles sourced using the keywords heparin, warfarin, perioperative, antiplatelet, aspirin and surgery was undertaken. A management plan for all likely situations was developed.

RESULTS AND CONCLUSION

Based on an individual assessment of risk factors for arterial or venous thromboembolism and the risk of perioperative bleeding, it is possible to form an anticoagulant and antiplatelet management plan likely to achieve a low incidence of bleeding and thrombosis. A multidisciplinary approach is desirable.

Coagulation and fibrosis in chronic liver disease

In the hepatic tissue repair mechanism, hepatic stellate cells (HSCs) are recruited at the site of injury and their changes reflect paracrine stimulation by all neighbouring cell types, including sinusoidal endothelial cells, Kupffer cells, hepatocytes, platelets and leucocytes. Thrombin converts circulating fibrinogen to fibrin, promotes platelet aggregation, is a potent activator of endothelial cells, acts as a chemoattractant for inflammatory cells and is a mitogen and chemoattractant for fibroblasts and vascular smooth muscle cells. Most of the cellular effects elicited by thrombin are mediated via a family of widely expressed G-protein-coupled receptors termed protease activated receptors (PARs). All known members of the PAR family stimulate cell proliferation/activation in a rat HSC line. Thrombin receptors are constitutively expressed in the liver, and their expression increases in parallel with the severity and/or the duration of liver disease. In human studies, thrombotic risk factors were found to be independently associated with the extent of fibrosis; severity of hepatitis C virus (HCV)-associated liver disease appears to be less in patients with haemophilia when compared with those with HCV alone. Several studies, based mostly on rat models, demonstrate that anticoagulants or antiplatelet agents prevent hepatic necrosis and fibrosis by acting on HSCs. These drugs could be therapeutic agents in patients with chronic liver disease and specific studies should be initiated.

Thrombin generation testing in routine clinical practice: are we there yet?

Thrombin is the central enzyme in the coagulation cascade. Estimation of an individual's potential to generate thrombin may correlate more closely with a hyper- or hypo-coagulable phenotype, compared to traditional coagulation tests. The possible correlation and recent technical advances in thrombin generation measurement has caused a significant interest in the method and the development of commercial assays. Several variations of the assay exist depending on the defect to be investigated. Fluorogenic thrombin generation assays have acceptable intra-laboratory variation but a higher inter-laboratory variation. Variation in preanalytical variables makes comparisons between studies difficult. Thrombin generation is highly variable between individuals and there are suggestions that this may allow individualized treatment based on global haemostatic response in patients with bleeding disorders or on anticoagulant therapy. In patients with thrombotic disorders it may be possible to identify those at higher risk of recurrent thrombosis. For both scenarios, however, data from large prospective studies are lacking or inconclusive and a good relationship between thrombin generation and phenotype remains to be established. Further standardization of the assay is needed before large multicentre studies can be conducted and until then thrombin generation in routine clinical practice is not yet a reality.

The effect of tissue factor concentration on calibrated automated thrombography in the presence of inhibitor bypass agents

Thrombin generation has been suggested as a method to monitor treatment with factor eight inhibitor bypassing activity (FEIBA) or recombinant FVIIa (rFVIIa). The sensitivity of the assay for individual coagulation factors is dependent on the tissue factor (TF) concentration. An inverse relation between the rFVIIa concentration needed to shorten the clotting time and TF concentration has been shown but the data on thrombin generation are inconsistent. Information on TF concentration in measurements with FEIBA is limited. We studied the influence of TF concentration (1 and 5 pM) on thrombin generation through spiking experiments with rFVIIa and/or FEIBA in the plasma of severe haemophilia A patients and after four and three treatment episodes, respectively, using the calibrated automated thrombin generation assay (CAT) in platelet poor plasma. Spiking with FEIBA showed a linear relation with the endogenous thrombin potential (ETP)/peak at 1 pM but substrate depletion at 5 pM. Spiking with rFVIIa showed a near linear dose-response relation with the ETP/peak at 1 pm but only a shortening of the initiation phase at 5 pM. Similar effects were present in post-treatment samples. FEIBA acted synergistically with rFVIIa. This suggest a role for CAT in monitoring inhibitor bypass treatment but low TF concentrations are required to avoid substrate depletion with FEIBA and to demonstrate the effect of rFVIIa.

Hyperhomocysteinemia in women with advanced breast cancer

Patients with malignancy have an increased risk of venous thromboembolic disease but the pathophysiology of this association has not been precisely defined. Hyperhomocysteinemia has become established as one of the commonest conditions associated with venous and arterial thrombosis. We examined the prevalence of hyperhomocysteinemia in women with early (group A, n = 31), metastatic breast cancer (group B, n = 41) and in a group of healthy females (group C, n = 29). Blood samples were collected at diagnosis or prior to treatment. We measured both total plasma homocysteine (tHcy) and red cell folate (RCF). The Mean (SD) tHcy were group A - 9.43 micromol/l (5.6), group B - 11.34 micromol/l (5.1) and group C - 7.9 micromol/l (1.5). A total of 39% of patients with metastatic and 22.6% with early breast cancer had tHcy concentrations above the upper limit of normal. Women with metastatic disease had significantly higher tHcy compared with controls (P < 0.01) but not when compared with women with early breast cancer. Also, no difference was observed when women with early disease were compared with controls. We found no correlation between age and tHcy. Lower RCF levels were identified in group B compared with group A, but this does not fully explain the increased tHcy levels seen within the same group. We conclude that hyperhomocysteinemia is common in women with advanced breast cancer. This observation could explain the high rate of venous thrombosis in women with metastatic breast malignancy.

The magnitude and distribution of infectious intestinal disease in Malta: a population-based study

Routine sources of information on infectious intestinal disease (IID) capture a fraction of the actual disease burden. Population studies are required to measure the burden of illness. A retrospective age-stratified cross-sectional telephone study was carried out in Malta in order to estimate the magnitude and distribution of IID at population level. A random sample of 3504 persons was interviewed by a structured questionnaire between April 2004 and December 2005. The response rate was 99.7%. From the study, the observed standardized monthly prevalence was 3.18% (95% CI 0.7-5.74) with 0.421 (95% CI 0.092-0.771) episodes of IID per person per year. The monthly prevalence was higher in the <5 years age group and in females aged 31-44 years. The mean duration of illness was 6.8 days and a median duration of 3 days. A bimodal seasonal distribution was observed with peaks in June-July and October-November.

Monitoring of the infrared radiation emitted from skin layers during CO2 laser resurfacing: a possible basis for a depth navigation device

CO2 laser resurfacing is very accurate, but it is not free of complications such as scarring. The objectives of the present study were to evaluate the pattern of the infrared (IR) radiation emitted from skin layers and to use this pattern to distinguish between these layers during resurfacing. A CO2-resurfacing laser (Sharplan SilkTouch) was used for the de-epithelialisation of skin. A silver halide optical fibre delivered the radiation emitted from the skin during resurfacing to an IR photonic detector. Time-dependent curves of the signals emitted from the skin layers were statistically evaluated and showed significant differences between the epidermis and the dermal layers. Similar results were obtained during in-vivo and ex-vivo measurements. The difference between the skin layers emission may be used for depth navigation during laser resurfacing.

Colchicine: an effective treatment for refractory malignant pericardial effusion

We report a patient with AL amyloidosis and chemo-resistant light-chain multiple myeloma who developed a progressive malignant pericardial effusion leading to cardiac tamponade. Despite pericardiocentesis and surgical intervention, the pericardial effusion failed to resolve. The administration of oral colchicine produced symptomatic relief within 5 days, with the resolution of pericardial effusion after 14 days of treatment. As the administration of colchicine is simple and the side-effect is usually minimal, further studies are warranted to establish the feasibility of using colchicine to treat malignant pericardial effusion.

Consequences of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor blockade during status epilepticus in the developing brain

To investigate if AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid) receptor activation contributes to acute manifestations and long term consequences of status epilepticus (SE), we administered the AMPA receptor antagonist NBQX to P35 rats undergoing kainic acid (KA)-induced SE. NBQX (30 mg/kg/dose) given intraperitoneally (i.p.) at 30, 60 and 90 min after i.p. KA injection (12 mg/kg) reduced severity of SE. When tested as adults, rats that had received KA and NBQX were similar to controls with no long term impairment in visuospatial memory (assessed by the water maze test), or histologic damage in the CA1 or CA3 hippocampal subfields. However, both P35 groups, those receiving KA alone and those receiving KA and NBQX, had similar rates of spontaneous recurrent seizures (SRS). In P15 rats, NBQX resulted in increased acute mortality from KA associated SE. These results indicate that the effects of NBQX on KA-induced SE are age dependent, and that non-NMDA receptor activation contributes to the acute manifestations and to the long term sequelae seen after KA-induced SE in the prepubescent rat brain.

Long-term behavioral deficits following pilocarpine seizures in immature rats

The effect of seizures on subsequent long-term behavior was studied in immature rats. A similar severity of seizures were induced in 20-day old rats (P20) and 45-day old rats (P45) by intraperitoneal injections of pilocarpine at doses of 200 mg/kg and 380 mg/kg, respectively. Immediately after injection of pilocarpine, prolonged seizures with electroencephalographic ictal discharges were observed in both groups of rats. These seizures were followed by seemingly complete neurological recovery. In rats that received pilocarpine at P45 spontaneous recurrent seizures appeared after 4-10 days and persisted until completion of the study at P100. Behavioral tests performed when the rats were fully mature demonstrated that they were more aggressive when handled, more active in open field, and had deficits in learning platform position in the water maze as compared to controls. Furthermore, flurothyl seizure latency was significantly lower in pilocarpine-treated P45 rats than controls. Histology examination showed gross cell loss in the CA3 subfield of the hippocampus in four out of six pilocarpine-treated rats while no cell loss was found in control rats. Rats that received pilocarpine at P20, despite having more severe seizures than the P45 rats, had no histological lesions, did not develop spontaneous recurrent seizures, and had no significant difference in the flurothyl seizure latency test when compared to their controls. While there was no difference between the control and pilocarpine-treated rats in the handling and open field test, P20 rats receiving pilocarpine were slower in learning platform position in the water maze than the controls. Rats receiving pilocarpine at P45 performed significantly more poorly than rats treated at P20 in the water maze. These results suggest that prolonged seizures in immature rats can cause long-term behavioral deficits. However, the severity and nature of these deficits are highly age dependent.

Phenobarbital modifies seizure-related brain injury in the developing brain

To investigate the potential role of drug therapy in preventing or exacerbating seizure-related brain injury in the prepubescent brain, we administered kainic acid to rats at postnatal day 35. Therapy with daily phenobarbital was started directly before or 1 day after kainic acid was administered, and was continued through postnatal day 153. Rats receiving phenobarbital had therapeutic concentrations during most of the 24-hour dosing period, but also experienced supratherapeutic peak concentrations. The animals were subsequently tested using the water maze (a measure of visuospatial memory), open field (a measure of activity level), and handling tests (a measure of emotionality). The frequency of spontaneous recurrent seizures was monitored during and after phenobarbital therapy. Kainic acid resulted in status epilepticus on postnatal day 35 in all the rats that received it but those receiving phenobarbital first manifested a shorter and less severe status epilepticus as compared to the rats given kainic acid alone. Rats starting phenobarbital immediately before kainic acid was administered did not differ from control rats on behavioral testing and had no subsequent spontaneous recurrent seizures and no histological lesions. Rats receiving kainic acid alone performed significantly poorer than did control rats in the water maze, were more aggressive, had histological lesions, and manifested spontaneous recurrent seizures. As compared to the group treated only with kainic acid, rats receiving kainic acid followed by phenobarbital at postnatal days 36 to 153 manifested similar aggressiveness and histological lesions, similar frequency of spontaneous recurrent seizures after phenobarbital taper, and even greater disturbances in memory, learning, and activity level.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of temperature on kainic acid-induced seizures

The effects of body temperature on kainic acid-induced seizures and seizure-related brain damage were examined in rats. In rats with status epilepticus induced by intraperitoneal injection of 12 mg/kg of kainic acid (KA), ictal discharges were decreased by 50% when body temperature was lowered to 28 degrees C and nearly abolished when body temperature was lowered to 23 degrees C. In rats with mild hypothermia (28 degrees C), the duration of ictal discharges following KA injection was significantly lower than in rats with normal body temperature. No detectable hippocampal cell loss was observed in rats with hypothermia to 28 degrees C whereas gross cell loss in the hippocampus was observed in all rats with KA injection at normal body temperature. In contract to hypothermia, hyperthermia markedly aggravated the seizures and hippocampal damage induced by KA. Following elevation of body temperature to 42 degrees C KA (12 mg/kg) resulted in severe seizures and all rats died of tonic seizures within 2 h. Furthermore, 6 mg/kg of KA administered to rats with a body temperature of 41-42 degrees C, resulted in up to 4 h of continuous ictal discharges whereas no continuous ictal discharges were observed after the same injections in rats with normal body temperature. Histological examination in rats receiving 6 mg/kg of KA revealed severe cell loss in the hippocampus in rats with hyperthermia but not in rats with normal temperature. These results demonstrate that body temperature plays an important role in the control of epileptic seizures and seizure-related brain damage.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuroprotective effect of chronic infusion of basic fibroblast growth factor on seizure-associated hippocampal damage

Basic fibroblast growth factor (bFGF) has been shown to have neuroprotective effects in animal models of ischemia. To determine whether bFGF is protective against seizure-induced brain damage, we administered bFGF through osmotic pumps prior to, and after treatment with kainic acid (KA). Recombinant bFGF, CS23, a modified human bFGF, was infused into the lateral ventricles in rats for 2 days before and 5 days after the injection of KA. Control rats received equal volumes of phosphated saline over the same period of time. Infusion of 5 micrograms/ml of bFGF (0.5 microliter/h) did not modify the latency and duration of seizures induced by intraperitoneal injections of KA. However, bFGF prevented cell loss in the hippocampus in 80% of the rats. In control rats, cell loss in the hippocampus was found in all rats. These results indicate that bFGF has a substantial neuroprotective effect.

Effects of quisqualic acid and glutamate on subsequent learning, emotionality, and seizure susceptibility in the immature and mature animal

To compare the long-term behavioral effects of chronic administration of excitatory amino acids in the mature and immature brain quisqualic acid (QA) and glutamate (GLU) were administered intraventricularly by osmotic pumps over 7 days in 20- and 60-day-old rats. Both age groups received identical dosages of QA or GLU. At age 90 days, all animals were assessed for abnormalities of learning and memory using the Morris water maze, emotionality using the handling test, and seizure threshold using flurothyl inhalation. No significant differences were found in either the water maze or handling test. However, 60-day-old rats receiving QA or GLU had more spontaneous seizures than the 20-day-old rats. In both age groups histological damage following QA and GLU was limited to the ipsilateral hippocampus, was maximum at the site of the catheter tube, and was similar in the two age groups studied. The adverse effects of long-term effects of chronic exposure to excitatory amino acids are similar in the immature and mature brain.