Energy attenuation performance of impact protection worn by motorcyclists in real-world crashes

OBJECTIVE

Laboratory studies have demonstrated that impact protectors (IP) used in motorcycle clothing can reduce fracture severities. While crash studies have reported IP are associated with reduced likelihood of soft tissue injury, there is little evidence of their effectiveness in reducing fracture likelihood. This discrepancy might be related to IP quality. There are mandatory requirements for IP supplied with protective clothing in Europe, but not elsewhere. This study examines the energy attenuation performance of IP used by Australian riders.

METHODS

IP were harvested from clothing worn by crashed riders admitted to hospital. The IP were examined and energy attenuation properties were determined using EN 1621-1 test procedures. Impact injury was identified from medical records and defined as fractures, dislocations, and avulsions that occurred following impact to the rider's shoulders, elbows, hips, and/or knees. Fisher's exact test was used to examine the relationship between meeting the EN 1621-1 energy attenuation requirements and impact injury. The association between the average and maximum transmitted force, and impact injury was examined using generalized estimating equations. Motorcycle riders were recruited as part of an in-depth crash study through three hospitals in New South Wales, Australia, between 2012 and 2014. Riders were interviewed, and engineers conducted site, vehicle, and clothing inspections. Clothing was collected, or identical garments were purchased.

RESULTS

Clothing was inspected for 62 riders. Of these, 19 wore clothing incorporating 76 IP. Twenty-six of these were impacted in the crash event. Almost all impacted IP (96%) were CE marked, and most (83%) met Level 1 energy attenuation requirements of EN 1621-1 when tested. Of the 26 impacted IP, four were associated with impact injuries, including midshaft and distal clavicle fractures and a scapula and olecranon fracture. No associations between meeting EN 1621-1 requirements and impact injury were found (p = 0.5). There was no association between average force transmitted and impact injury (95% CI: 0.91-1.24); however, as maximum force transmitted increased, the odds of impact injury increased (95% CI: 1.01-1.2). These results indicate a high probability of impact injury at 50 kN, the limit of maximum transmitted force specified in EN 1621-1.

CONCLUSION

The allowable transmitted force of EN 1621-1 may be too high to effectively reduce the probability of impact injury. This is not surprising, given human tolerance levels that are reported in literature. Reducing the force limit below the reported fracture tolerance limits might be difficult with current technology. However, there is scope to reduce the EN 1621-1 maximum limit of 50 kN transmitted force. A reduction in the maximum force limit would improve rider protection and appears feasible, as 77% of tested IP recorded a maximum force <35 kN. This level of transmitted force is estimated to be associated with <20% probability of impact injury. While the performance of IP available to Australian riders is not regulated, most IP was CE marked. The results indicate a significant association between maximum transmitted force, tested according to EN 1621-1 procedures, and impact injury. Further investigation of the EN 1621-1 requirements may be warranted. This work will interest those targeting protective equipment for motorcyclists as a mechanism for reducing injury to these vulnerable road users.

Exploratory field trial of motorcycle autonomous emergency braking (MAEB): Considerations on the acceptability of unexpected automatic decelerations

OBJECTIVE

Autonomous emergency braking (AEB) acts to slow down a vehicle when an unavoidable impending collision is detected. In addition to documented benefits when applied to passenger cars, AEB has also shown potential when applied to motorcycles (MAEB). However, the feasibility of MAEB as practically applied to motorcycles in the real world is not well understood.

METHODS

In this study we performed a field trial involving 16 riders on a test motorcycle subjected to automatic decelerations, thus simulating MAEB activation. The tests were conducted along a rectilinear path at nominal speed of 40 km/h and with mean deceleration of 0.15 g (15% of full braking) deployed at random times. Riders were also exposed to one final undeclared brake activation with the aim of providing genuinely unexpected automatic braking events.

RESULTS

Participants were consistently able to manage automatic decelerations of the vehicle with minor to moderate effort. Results of undeclared activations were consistent with those of standard runs.

CONCLUSIONS

This study demonstrated the feasibility of a moderate automatic deceleration in a scenario of motorcycle travelling in a straight path, supporting the notion that the application of AEB on motorcycles is practicable. Furthermore, the proposed field trial can be used as a reference for future regulation or consumer tests in order to address safety and acceptability of unexpected automatic decelerations on a motorcycle.

A robust estimation of the effects of motorcycle autonomous emergency braking (MAEB) based on in-depth crashes in Australia

OBJECTIVE

Autonomous emergency braking (AEB) is a safety system that detects imminent forward collisions and reacts by slowing down the host vehicle without any action from the driver. AEB effectiveness in avoiding and mitigating real-world crashes has recently been demonstrated. Research suggests that a translation of AEB to powered 2-wheelers could also be beneficial. Previous studies have estimated the effects of a motorcycle AEB system (MAEB) via computer simulations. Though effects of MAEB were computed for motorcycle crashes derived from in-depth crash investigation, there may be some inaccuracies due to limitations of postcrash investigation (e.g., inaccuracies in preimpact velocity of the motorcycle). Furthermore, ideal MAEB technology was assumed, which may lead to overestimation of the benefits. This study sought to evaluate the sensitivity of the simulations to variations in reconstructed crash cases and the capacity of the MAEB system in order to provide a more robust estimation of MAEB effects.

METHODS

First, a comprehensive classification of accidents was used to identify scenarios in which MAEB was likely to apply, and representative crash cases from those available for this study were populated for each crash scenario. Second, 100 variant cases were generated by randomly varying a set of simulation parameters with given normal distributions around the baseline values. Variants reflected uncertainties in the original data. Third, the effects of MAEB were estimated in terms of the difference in the impact speed of the host motorcycle with and without the system via computer simulations of each variant case. Simulations were repeated assuming both an idealized and a realistic MAEB system. For each crash case, the results in the baseline case and in the variants were compared. A total of 36 crash cases representing 11 common crash scenarios were selected from 3 Australian in-depth data sets: 12 cases from New South Wales, 13 cases from Victoria, and 11 cases from South Australia.

RESULTS

The reduction in impact speed elicited by MAEB in the baseline cases ranged from 2.8 to 10.0 km/h. The baseline cases over- or underestimated the mean impact speed reduction of the variant cases by up to 20%. Constraints imposed by simulating more realistic capabilities for an MAEB system produced a decrease in the estimated impact speed reduction of up to 14% (mean 5%) compared to an idealized system.

CONCLUSIONS

The small difference between the baseline and variant case results demonstrates that the potential effects of MAEB computed from the cases described in in-depth crash reports are typically a good approximation, despite limitations of postcrash investigation. Furthermore, given that MAEB intervenes very close to the point of impact, limitations of the currently available technologies were not found to have a dramatic influence on the effects of the system.

Headache Treatment Before and After the Consultation of a Specialized Centre: A Pharmacoepidemiology Study

Our aim was to study and compare pharmacoepidemiology of headache treatment in two different settings: inside and outside a specialized Centre. We analysed the differences in headache treatment between 612 subjects admitted for the first visit (‘naive’) (F/M: 2.41; mean age = 37.31 ± 14.09 years) and 620 subjects admitted for a control visit (F/M: 3.18; mean age = 44.30 ± 15.37 years) to the Headache Centre of the University of Modena and Reggio Emilia. Most patients suffered from migraine. As acute treatment, on the first visit, 49.4% of them were taking drugs prescribed by a doctor; 41.5% were taking over-the-counter analgesics (OTCAs); 9.1% were not taking any drug. On the control visit, 81.3% of patients were taking prescription drugs; 15.8% OTCAs; 2.9% were not taking drugs (overall chi-square = 139.229, P < 0.001). Non-selective analgesics were the most-used drugs. Triptans were used by 9.1% of ‘naive’ patients and by 31.8% of patients attending for the control visit (Fisher's Z = 7.655, P < 0.001). Nimesulide was the most-used drug. A prophylactic treatment was made by 16.8% of ‘naive’ patients, and by 58.2% of patients admitted to the control visit (Fisher's Z = 12.135, P < 0.001). Antidepressants were the class of drugs most used for prophylaxis. Amitriptyline was the drug for prophylaxis most frequently used by patients attending the control visit, while flunarizine was the most frequently used by ‘naive’ patients. Before being examined in a specialized centre, few patients take prescription drugs, triptans, or prophylactic drugs; specialized care increases the proportion of patients taking prophylactic drugs, and changes the type of acute treatment used into disease-specific medication for headache.

Reconsidering the safety in numbers effect for vulnerable road users: an application of agent-based modeling

OBJECTIVE

Increasing levels of active transport provide benefits in relation to chronic disease and emissions reduction but may be associated with an increased risk of road trauma. The safety in numbers (SiN) effect is often regarded as a solution to this issue; however, the mechanisms underlying its influence are largely unknown. We aimed to (1) replicate the SiN effect within a simple, simulated environment and (2) vary bicycle density within the environment to better understand the circumstances under which SiN applies.

METHODS

Using an agent-based modeling approach, we constructed a virtual transport system that increased the number of bicycles from 9% to 35% of total vehicles over a period of 1,000 time units while holding the number of cars in the system constant. We then repeated this experiment under conditions of progressively decreasing bicycle density.

RESULTS

We demonstrated that the SiN effect can be reproduced in a virtual environment, closely approximating the exponential relationships between cycling numbers and the relative risk of collision as shown in observational studies. The association, however, was highly contingent upon bicycle density. The relative risk of collisions between cars and bicycles with increasing bicycle numbers showed an association that is progressively linear at decreasing levels of density.

CONCLUSIONS

Agent-based modeling may provide a useful tool for understanding the mechanisms underpinning the relationships previously observed between volume and risk under the assumptions of SiN. The SiN effect may apply only under circumstances in which bicycle density also increases over time. Additional mechanisms underpinning the SiN effect, independent of behavioral adjustment by drivers, are explored.

Atherosclerotic coronary plaque in subjects with diabetic neuropathy: the prognostic cardiovascular role of Charcot neuroarthropathy--a case-control study

The aim of this study was to investigate the severity of coronary artery disease (CAD) and the plaque composition in neuropathic type 2 diabetic subjects with and without Charcot neuroarthropathy (CN) undergoing multidetector computed tomography coronary angiography (MDCT-CA). The study was a single-center, observational, with unmatched case-control design. We selected 17 CN patients and 18 patients with diabetic neuropathy (DN) without CN. In all the patients, multidetector computed tomography was performed to assess the coronary artery calcium score (CACS) and degree of coronary artery stenosis. Patients were classified as positive in the presence of significant CAD if there was at least one stenosis >50 % on MDCT-CA. The invasive coronary angiography was performed in case of significant stenosis detected with MDCT-CA, both as reference to standard and eventually as treatment. Groups were matched for age, sex, and traditional CAD risk factors. As compared to DN individuals, CN exhibited higher rates of significant coronary stenoses (p = 0.027; OR 7.7 [1.3-43.5]). However, no significant differences were observed in the CACS, which reflects plaque burden, in the two groups (p = 0.759). No significant differences were observed comparing CACS distribution in all subjects for stenosis higher/equal or lower than 50 % (p = 0.320). Finally, no significant differences were observed comparing CACS distribution in CN and DN subjects for coronary stenoses higher/equal or lower than 50 %. Our results suggest that CN patients have a higher prevalence of severe coronary plaques compared to DN patients. Nevertheless, coronary plaques in CN patients did not exhibit an increased degree of calcification.

Further development of Motorcycle Autonomous Emergency Braking (MAEB), what can in-depth studies tell us? A multinational study

OBJECTIVE

In 2006, Motorcycle Autonomous Emergency Braking (MAEB) was developed by a European Consortium (Powered Two Wheeler Integrated Safety, PISa) as a crash severity countermeasure for riders. This system can detect an obstacle through sensors in the front of the motorcycle and brakes automatically to achieve a 0.3 g deceleration if the collision is inevitable and the rider does not react. However, if the rider does brake, full braking force is applied automatically. Previous research into the potential benefits of MAEB has shown encouraging results. However, this was based on MAEB triggering algorithms designed for motorcycle crashes involving impacts with fixed objects and rear-end crashes. To estimate the full potential benefit of MAEB, there is a need to understand the full spectrum of motorcycle crashes and further develop triggering algorithms that apply to a wider spectrum of crash scenarios.

METHODS

In-depth crash data from 3 different countries were used: 80 hospital admittance cases collected during 2012-2013 within a 3-h driving range of Sydney, Australia, 40 crashes with Injury Severity Score (ISS)>15 collected in the metropolitan area of Florence, Italy, during 2009-2012, and 92 fatal crashes that occurred in Sweden during 2008-2009. In the first step, the potential applicability of MAEB among the crashes was assessed using a decision tree method. To achieve this, a new triggering algorithm for MAEB was developed to address crossing scenarios as well as crashes involving stationary objects. In the second step, the potential benefit of MAEB across the applicable crashes was examined by using numerical computer simulations. Each crash was reconstructed twice-once with and once without MAEB deployed.

RESULTS

The principal finding is that using the new triggering algorithm, MAEB is seen to apply to a broad range of multivehicle motorcycle crashes. Crash mitigation was achieved through reductions in impact speed of up to approximately 10 percent, depending on the crash scenario and the initial vehicle pre-impact speeds.

CONCLUSIONS

This research is the first attempt to evaluate MAEB with simulations on a broad range of crash scenarios using in-depth data. The results give further insights into the feasibility of MAEB in different speed ranges. It is clear then that MAEB is a promising technology that warrants further attention by researchers, manufacturers, and regulators.

Analysis of the minimum swerving distance for the development of a motorcycle autonomous braking system

In the recent years the autonomous emergency brake (AEB) was introduced in the automotive field to mitigate the injury severity in case of unavoidable collisions. A crucial element for the activation of the AEB is to establish when the obstacle is no longer avoidable by lateral evasive maneuvers (swerving). In the present paper a model to compute the minimum swerving distance needed by a powered two-wheeler (PTW) to avoid the collision against a fixed obstacle, named last-second swerving model (Lsw), is proposed. The effectiveness of the model was investigated by an experimental campaign involving 12 volunteers riding a scooter equipped with a prototype autonomous emergency braking, named motorcycle autonomous emergency braking system (MAEB). The tests showed the performance of the model in evasive trajectory computation for different riding styles and fixed obstacles.

Intraorbital injection of rituximab: a new approach for active thyroid-associated orbitopathy, a prospective case series

AIM

The aim of this paper was to examine the efficacy and the safety of intraorbital administration of the monoclonal anti-CD20 antibody rituximab (RTX) to treat patients affected by thyroid-associated orbitopathy (TAO) unresponsive to conventional therapy.

METHODS

Five patients with active moderately-severe TAO unresponsive to systemic glucocorticoids were studied. After a complete ophthalmological examination, disease activity and severity were assessed by the clinical activity score (CAS) and the NO SPECS scoring system. Computed tomography scans were performed in all patients. Patients were treated with intraorbital injection of RTX 10 mg once a week for one month repeated once one month apart. The patients were followed every three months until 18 months.

RESULTS

In all patients treated with RTX, CAS was significantly reduced (p< 0,005), inactive phase of TAO was reached in four out of five patients. No patients experienced major side effects, minor side effects were reported in two patients.

CONCLUSION

Intraorbital injection of RTX is a safe and useful promising therapeutic option for active TAO.

Assessing the potential benefits of the motorcycle autonomous emergency braking using detailed crash reconstructions

OBJECTIVE

The aim of this study was to assess the feasibility and quantitative potential benefits of a motorcycle autonomous emergency braking (MAEB) system in fatal rear-end crashes. A further aim was to identify possible criticalities of this safety system in the field of powered 2-wheelers (PTWs; e.g., any additional risk introduced by the system itself).

METHODS

Seven relevant cases from the Swedish national in-depth fatal crash database were selected. All crashes involved car-following in which a non-anti-lock braking system (ABS)-equipped motorcycle was the bullet vehicle. Those crashes were reconstructed in a virtual environment with Prescan, simulating the road scenario, the vehicles involved, their precrash trajectories, ABS, and, alternatively, MAEB. The MAEB chosen as reference for the investigation was developed within the European Commission-funded Powered Two-Wheeler Integrated Safety (PISa) project and further detailed in later studies, with the addition of the ABS functionality. The boundary conditions of each simulation varied within a range compatible with the uncertainty of the in-depth data and also included a range of possible rider behaviors including the actual one. The benefits of the MAEB were evaluated by comparing the simulated impact speed in each configuration (no ABS/MAEB, ABS only, MAEB).

RESULTS

The MAEB proved to be beneficial in a large number of cases. When applicable, the benefits of the system were in line with the expected values. When not applicable, there was no clear evidence of an increased risk for the rider due to the system.

DISCUSSION AND LIMITATIONS

MAEB represents an innovative safety device in the field of PTWs, and the feasibility of such a system was investigated with promising results. Nevertheless, this technology is not mature yet for PTW application. Research in the field of passenger cars does not directly apply to PTWs because the activation logic of a braking system is more challenging on PTWs. The deployment of an autonomous deceleration would affect the vehicle dynamics, thus requesting an additional control action of the rider to keep the vehicle stable. In addition, the potential effectiveness of the MAEB should be investigated on a wider set of crash scenarios in order also to avoid false triggering of the autonomous braking.

Evaluation of an autonomous braking system in real-world PTW crashes

OBJECTIVES

Powered 2-wheelers (PTWs) are becoming increasingly popular in Europe. They have the ability to get around traffic queues, thus lowering fuel consumption and increasing mobility. The risk of rider injury in a traffic crash is however much higher than that associated with car users. The European project, Powered Two Wheeler Integrated Safety (PISa), identified an autonomous braking system (AB) as a priority to reduce the injury consequences of a PTW crash. The aim of this study was to assess the potential effectiveness of the AB system developed in PISa, taking into account the specific system characteristics that emerged during the design, development and testing phases.

METHODS

Fifty-eight PTW cases representing European crash configurations were examined, in which 43 percent of riders sustained a Maximum Abbreviated Injury Scale (MAIS) 2+ injury. Two of the most common crash types were a PTW impacting a stationary object (car following scenario) 16% and an object pulling across the PTW path (crossing scenario) 54%. An expert team analysed the in-depth material of the sample crashes and determined a posteriori to what extent the AB would have affected the crash. For those cases where the AB was evaluated as applicable, a further quantitative evaluation of the benefits was conducted by considering a set of different possible rider reactions in addition to that exhibited in the actual crash.

RESULTS

In 67 percent of cases, the application of AB could have mitigated the crash outcome. Analysis of those real crash cases showed the potential for an expert rider to avoid the collision. An early reaction of the rider, associated with a correct application of the brakes would have avoided 18 of the 37 car following/crossing scenarios. Conversely, according to the analysis, an expert rider would not have been able to avoid 19 of the 37 cases. In 14 of those 19 cases, the AB would have contributed to mitigating the crash outcome.

CONCLUSIONS

This study demonstrated significant potential for application of the autonomous braking system in car following and crossing scenarios. In addition, the theoretical benefit curves for the AB globally, were able to provide good quantitative indications of its benefits in real cases where the AB was considered applicable. Further analysis with larger databases is suggested in order to confirm the magnitude of benefits in the PTW crash population.

[Micromedullary thyroid carcinoma: school experience]

Medullary microcarcinomas occurrence are rare and fortuitous, it's usually related to the calcitonin measurement, that's the gold standard for the diagnosis. In other cases performing a thyroidectomy for a benign thyroid disease it's found a sub-centimeter tumor. Actually it's not clear the most appropriate surgical treatment for those kind of tumors because the number of cases in literature is limited and because there are different surgical approaches. In this study 17 patients were operated for medullary thyroid microcarcinoma and the Authors found central lymph node metastases in 33.3% of cases. The Authors, analyzing those results, think that total thyroidectomy with lymphadenectomy of the central compartement is the best choice in a sporadic microcarcinoma, while a total thyroidectomy without lymphadenectomy should be performed when the microcarcinomas are incidentals.

[Case-mix index and length of hospitalization]

The ACG (Adjusted Clinical Groups) case-mix system is a classification method of diseases of patients, focused on the person. Depending on the pattern of these morbid conditions, the ACG system assigns each patient to a single group (an ACG group), which allows to capture the effects of a group of diseases in estimates of resource use. Diseases are classified into a diagnostic group (ADG) according to 5 clinical dimensions: duration (acute, recurrent or chronic), severity (minor/major vs stable/unstable), diagnostic assessment (symptoms vs diseases), etiology (infectious, traumatic or other), specialty (medical, surgical, obstetric, ...). All diseases can be classified into these dimensions and into one of 32 groups. The ACG case-mix system uses an algorithm to classify each patient into one of 93 ACG categories. Each person is assigned to an ACG according to his ADG combination, his age and his gender. With the repayment system "case-mix", surgery has become central for all great hospitals in virtue of its great productive potential. The case-mix index is one of the factors which influence the duration of hospitalization. The case-mix system has emphasized the importance of the duration of hospitalization, encouraging the planning of programs in order to discharge patients early after surgical operations. It has also stimulated the surgical activity in operating units with "budget" forecasts in which resources are provided according to an expected level of specialist surgery.

[Medullary thyroid carcinoma: a study about 28 operated patients]

In this study on 28 operated patients, the Authors show that total thyroidectomy with elective central neck dissection and ipsilateral neck dissection is the most appropriate surgical treatment for medullary thyroid carcinoma. Pathologic study on lymph nodes removed in central and in latero-cervical compartments showed malignancy respectively in 75% and in 70% of the cases. However the role of elective ipsilateral lateral neck dissection remains controversial.

[Retroperitoneal giant mixed sarcoma. Case report]

The Authors present a rare case of voluminous retroperitoneal tumor in a 41 years old woman. CT scan showed a solid abdominal expansive mass, with compression and displacement of the left lobe of the liver, spleen, stomach, pancreas, and left kidney. The patient underwent surgery for excision of a giant retroperitoneal mass. Surgery was uneventful. The patients recovered well. Histology showed a mixed liposarcoma and angiosarcoma with high grade of malignancy and positivity for vimentin, factor VIII, CD34, CD31 and negativity for S-100, CD68, AMS, AML. The prognosis of these tumours is closely related to local recurrence, histological type, size and radical surgery. A low-grade malignancy tumor, small sized and completely resected leads to a good prognosis. Radiation therapy and chemotherapy do not seem to have a strong influence on the prognosis. An aggressive surgical approach is the first choice for the treatment of such tumors. The resection of adjacent organs may be required for radical surgery.

[Two cases of synchronous papillary and medullary thyroid carcinoma]

The Authors describe two cases of simultaneous association of papillary and medullary thyroid carcinoma. They emphasize the treatment of these cases stressing the correlation between the therapeutic criteria and the malignancy of medullary carcinoma.

64 slice cardiovascular CT in the emergency department: concepts and first experiences

PURPOSE

The purpose of this study was to evaluate contrast-enhanced electrocardiogram (ECG)-gated 64-slice computed tomography (CT) angiography of the thorax as a triage tool in patients with acute equivocal chest pain.

MATERIAL AND METHODS

Technical principles and diagnostic algorithms for using a single ECG-gated 64-slice CT scan for triple rule-out of acute pulmonary embolism, aortic dissection, acute coronary syndromes and other diseases of the chest are introduced. Our experience using this test in 23 patients are reviewed and exemplary cases are illustrated. The total length of hospitalisation and charges for Emergency Department care at the time of discharge were compared with a matched control population that underwent catheter angiography for emergent cardiac workup. Statistical analyses were performed with an independent Student's t test. Mann-Whitney rank sum test was also used on variables that did not have equal variance.

RESULTS

Of the 23 patients, 11 presented without pathological findings, two with extensive pulmonary embolism, two with definite coronary artery disease (CAD) but stenosis <50% and eight with significant CAD (>50% stenosis). Catheter angiography was performed in the latter group, confirming the CT findings in all cases. Nine patients without CT findings were discharged on the same day. In comparison with the control group, length of hospitalisation (p=0.009) and total hospital charges (p<0.001) were significantly reduced.

CONCLUSIONS

Our initial experience shows that ECG-gated 64- slice CT angiography of the entire thorax is technically feasible and enables rapid triage of patients to determine underlying cardiac and noncardiac reasons for chest pain. This test may thus help to significantly reduce costs and length of hospitalisation. Prospective studies involving larger groups of patients are required to confirm these findings.

Pharmacokinetics of a new extended-release nifedipine formulation following a single oral dose, in human volunteers

This study aimed to define the pharmacokinetics of nifedipine following oral administration of a new extended-release formulation. Twelve healthy volunteers of both sexes, aged 39 +/- 4 years, were treated with a single oral tablet of a new extended-release formulation containing 40 mg of nifedipine. Samples of venous blood were taken before dosing, after 30 min and at 1, 2, 4, 8, 12, 16, 20 and 24 h after administration. Nifedipine concentration was measured by means of a high-performance liquid chromatography method. Noncompartmental pharmacokinetics parameters were then calculated. The plasma concentration of nifedipine increased slowly and in seven subjects biphasic peaks occurred. The mean values were as follows: t(max): 8.5 +/- 1.2 h; C(max): 36.55 +/- 6.76 ng/ml; AUC: 347.06 +/- 51.61 ng/h/ml; AUC 409.99 +/- 61.08 ng/h/ml; A(half-life): 2.26 +/- 0.36 h; D(half-life): 2.43 +/- 0.44 h; E(half-life): 4.62 +/- 0.79 h. Twenty-four hours after administration nifedipine was still detectable (3.17 +/- 0.67 ng/ml). Arterial blood pressure decreased and heart rate increased concurrently and proportionally to the increase in nifedipine concentration. Extended-release nifedipine formulations have better tolerability profiles than immediate-release formulations, which are at present not recommended in the treatment of hypertension, hypertensive crises or myocardial infarction. This new extended-release formulation has interesting pharmacokinetic parameters and may be effective in conditions in which dihydropyridine calcium channel blockers are indicated.

Panax notoginseng (Burk.) effects on fibrinogen and lipid plasma level in rats fed on a high-fat diet

Several studies have shown that notoginsenoides improve diastolic function in hypertensive subjects, induce the fibrinolytic system in in vitro models and act as antiproliferative agents on vessel leiomyocytes. Our aim was to evaluate their effect on fibrinogen and lipid plasma levels compared with a well-known HMGCoA reductase inhibitor. Seventy Wistar male adult rats on a fat-enriched diet were treated orally with P. notoginseng pulverized root (43 mg/kg/day or 86 mg/kg/day; 20 animals per group), fluvastatin (3 mg/kg/day; 20 animals) or physiological saline (5 mL/kg/day; 10 animals). The ten rats on a normocaloric diet were also treated with 5 mL/kg/day of physiological saline. After a 28-day treatment, the rats were killed and their blood analysed with standard procedures. Treatment with 43 mg/kg/day of P. notoginseng or 3 mg/kg/day of fluvastatin showed similar activity in decreasing total cholesterol (-23.70%, -19.29%, respectively) and triglycerides (-21.59%, -18.55%). The most evident effect of P. notoginseng was the reduction of fibrinogenaemia in treated rats compared with the control values (-38.10%; p < 0.001), no dose-relationship being shown in this effect. Moreover, no significant variation in HDL cholesterol and glucose levels was observed nor did relevant behavioural changes occur in association with the root intake. Besides a moderate, non dose-related decrease in the plasma lipid levels, P. notoginseng appeared to induce a significant reduction in the rat fibrinogenaemia.