bluuebunny/crossref_metadata_2025 huggingface dataset:
Chronic Animal Experiment with Magnetically Suspended Centrifugal Pump
Authors: Yamada Tomoyuki , Nishimura Kazunobu , Park Chang‐Hee , Kono Satoshi , Yuasa Sadatoshi , Tsukiya Tomonori , Akamatsu Teruaki , Matsuda Katsuhiko , Ban Toshihiko
Published: November 2008

Abstract: We have been developing a new type of centrifugal pump for long‐term use. The magnetically suspended centrifugal pump (MSCP) contains no shaft and seal so that long life expectancy is predicted. Paracorpo‐real left ventricular (LV) assist circulation between the left atrium and the descending aorta was instituted using sheep. The flow rates ranged from 2.5–5.5 Limin. The sheep that lived the longest (46 days) died of an embolism as a result of the thrombus in the pump. No thrombus formation was observed in other pumps. Plasma free hemoglobin levels ranged from 9 to 18 mg/dl, which led to the conclusion that the hemolysis level remained within an acceptable range. Two driving modes were compared. The slope of the pressure‐flow relationship plot under a constant motor current mode was steeper than that under a constant rotational speed mode, and thus. the flow fluctuation decreased. In conclusion, the MSCP is durable for more than a month at the current stage of development and is a promising device for long‐term ventricular assist.
Long‐Term Evaluation of a Nonpulsatile Mechanical Circulatory Support System
Authors: Wakisaka Yoshinari , Taenaka Yoshiyuki , Chikanari Kenichi , Nakatani Takeshi , Tatsumi Eisuke , Masuzawa Tom , Nishimura Takashi , Takewa Yoshiaki , Ohno Takashi , Takano Hisateru
Published: November 2008

Abstract: Antithrombogenicity of a centrifugal pump (CP) developed in our institute is provided by a central balancing hole (BH) in the impeller. A current CP, the National Cardiovascular Center (NCVC)‐2, was ameliorated to improve antithrombogenicity, whereby the BH diameter was widened to improve self washout flow velocity, and an edge of the thrust bearing was rounded off to minimize flow separation. Effects of these modifications were assessed in a long‐term in vivo experiment. The antithrombogenicity, hemolytic property, and mechanical durability of the NCVC‐2 were investigated in 3 goats. The NCVC‐2 was installed paracorporeally between the left atrium and the aorta and driven as long as possible at rotating speeds of about 2,800 rpm. The NCVC‐2 ran for 50, 200, and 367+ days. The mean bypass flow rates were 6.8, 5.0, and 5.3 Wmin, respectively. Creatinine, blood urea nitrogen (BUN), glutamic‐oxaloacetic transaminase (GOT), and glutamic‐pyruvic transaminase (GPT) did not increase until one week before termination. Plasma free hemoglobin was kept to a level less than 15 mg/dl, except for the last week of the second case. These results indicate that the NCVC‐2 has excellent antithrombogenicity, an acceptable hemolytic property and the necessary durability for prolonged use.
Realization of a Permanent Implantable Pulsatile Impeller Heart with Magnetically Suspended Motor
Authors: Qian K.X. , Zheng M.
Published: November 2008

Abstract: A permanent impeller heart that could work for years was once an idea. However, now this idea is turning into reality through the use of the magnetically suspended motor. Recently, with our implantable pulsatile impeller pump, 3 left ventricular assisted calves survived for about 2 months (62, 54, and 46 days, respectively). The termination of the experiments was related to wear of the mechanical bearing, which resulted in vibration of the rotor and pump failure. All the experimental animals were in good condition prior to pump failure. It seemed as if the experiments could have lasted indefinitely if the bearing had not failed. All the hematological and biochemical data of the calves remained in normal or acceptable ranges; neither blood damage nor organ dysfunction of any animal was detected. During autopsy, no severe thrombus formation was found in the pump or vessels although a low dose of heparin (0.548 g/h) was given to increase the activated coagulation time (ACT) to 1.5–2.0 times its normal value. To solve the problem of bearing wear, a magnetically suspended motor was investigated and applied to the impeller pump. On the opposite sides of a disc connected to the rotor, 2 permanent magnet rings were embedded, one for driving and the other for axial suspension. Because both the driving and suspending coils with iron cores attract the disc, no radial bearing was needed. This newly devised impeller heart promises to have long‐term and permanent applications.
Flow Visualization Studies to Improve the Spiral Pump Design
Authors: Andrade Aron , Biscegli José , Sousa José Eduardo , Ohashi Yukio , Nosé Yukihiko
Published: November 2008

Abstract: The spiral pump (SP) uses centrifugal and axial pumping principles simultaneously, through a conical shaped impeller with threads in its surface. Flow visualization studies were performed in critical areas of the SP. A closed circuit loop was filled with glycerin‐water solution (40%). Amberlite particles (80 mesh) were illuminated by a planar helium‐neon laser light (7 mW). The particle velocities were recorded with Kodak (TMAX‐400) black and white film, and the flow behavior was studied with a micro video camera and color video printer. The flow visualization studies showed no turbulence or stagnant areas in the inlet and outlet ports of the SP. When using the impeller with one lead, at the top of the threads some recirculation appeared when the total pressure head increased. Two new impellers were made. One of them had the same conical shape with a thread having 2 leads. The second had a thread with 2 leads, but it also had a bigger cone angle. These modifications improved the pump hydrodynamic performance, decreasing the recirculation in pumping conditions that require pressures over 200 mm Hg.
Hemolytic Effect of the Secondary Vane Incorporated into the Back Side of the Impeller
Authors: Ohara Yasuhisa , Murase Mitsuya , Nosé Yukihiko
Published: November 2008

Abstract: The hemolytic effect of the secondary vane system, the antithrombogenic structure incorporated into the back side of the impeller of the C1E3 Gyro pump, was investigated. Impellers with 0, 2, 3, and 4 secondary vanes and an additional impeller with 2 secondary channels were fabricated and incorporated into the C1E3 pump casings. Hemolysis tests were performed under cardiopulmonary bypass conditions (flow rate 4.5 L/min, total pressure head 350 mm Hg) using flesh bovine blood. The normalized indices of hemolysis (NIH) of the pumps with 0, 2, 3, and 4 secondary vanes and the pump with 2 secondary channels were 0.0797, 0.0866, 0.104, 0.157, and 0.0591, respectively. These results indicated that design of the impeller with 2 secondary channels, which was the original design of C1E3 Gyro pump, was less hemolytic than the design with secondary vanes. Additionally, the possibility of the secondary channel system for the impeller bottom was demonstrated favorably.
Reconsideration of Total Erythrocyte Destruction Phenomenon
Authors: Tayama Eiki , Shimono Takatsugu , Makinouchi Kenzo , Ohtsubo Satoshi , Nakazawa Tadashi , Takami Yoshiyuki , Niimi Yoshinari , Glueck Julie , Nosé Yukihiko
Published: November 2008

Abstract: During a particular long‐term in vitro hemolysis test, the plasma free hemoglobin suddenly increased even though the hemolysis level had risen linearly for the previous several hours. This phenomenon was dubbed the total destruction of erythrocytes (TDE) phenomenon, and it was hypothesized that this was the result of the accumulation of sublethal damage to erythrocytes. It was suggested that the TDE might demonstrate the hemolytic characteristics of a pump more sensitively than a conventional hemolysis test. However, the previous report did not consider the effects of temperature or contamination. To study these effects, 3 long‐term hemolysis tests were concluded under the following conditions. For Study 1 blood temperature was maintained at 27°C (n = 2); for Study 2, at 37°C (n = 4); and for Study 3, at 37°C with gentamicin (n = 4). The BioMedicus and Nikkiso pumps were used as they were in our previous report. Gas sterilization of all circuits and pumps preceded experimentation. In Studies 1 and 3, hemolysis increased linearly for 29 h. However, in Study 2 a sudden increase of hemolysis occurred for both pumps. Possible causes of this were the dramatic changes in environmental factors such as severe acidosis, high 0, and glucose consumption, and CO2accumulation. In contrast, neither Study 1 nor Study 3 showed a sudden increase in hemolysis. The plasma free hemoglobin increased linearly in both groups until 29 h of pumping. The environmental changes resulting from contamination were considered to be the cause of the sudden increase in hemolysis. In conclusion, the TDE did not reflect mechanical blood cell damage, but rather different environment situations. Hemolysis increased linearly up to 29 h in either 27°C or germ‐free conditions.
Quantitative Visualization of Flow Through a Centrifugal Blood Pump: Effect of Washout Holes
Authors: Nishida Masahiro , Yamane Takashi , Orita Toyoki , Asztalos Balázs , Clarke Helen
Published: November 2008

Abstract: To clarify the effect of washout holes on the flow in a centrifugal blood pump to prevent blood stagnation, a quantitative flow visualization technique was applied to compare flows in models with and without washout holes. A scaled‐up model of a prototype pump and a high speed video camera were used for the flow visualization, and images were processed by particle tracking ve‐locimetry. Particular attention was paid to the flow through the gaps behind and in front of the impeller. The results showed that in the gap behind the impeller, washout holes caused not only an inward flow, but also an increase in the tangential velocities. In the gap in front of the impeller, washout holes caused an outward flow and a decrease in the tangential velocities. Head flow characteristics were little affected by the washout holes in this initial design for which the flow through the washout holes was set to be approximately 10% of the flow in the external circuit. These results suggest that the flow through washout holes is significant in the prevention of blood stagnation in 2 ways. First, the inward radial velocity behind the impeller and outward velocity in front of the impeller result in fluid exchange, and second, a tangential velocity increase reduces fluid stagnation behind the impeller.
Trial Manufacture of Eccentric Roller Type Total Artificial Heart
Authors: Sueshiro Masafumi , Fukunaga Shintaro , Mitsui Norimasa , Hirai Shinji , Koura Yoshihiko , Hotei Hiroshi , Sueda Taijiro , Katsuhara Kimiko , Matsuura Yuichiro , Koguchi Shinsaku
Published: November 2008

Abstract: Working toward a completely implantable total artificial heart, we have designed an eccentric roller type total artificial heart. The actuator of this artificial heart is a drum type eccentric roller that squeezes the blood chambers. The blood chambers are made of silicone rubber and are torus in shape. The shape of the artificial heart is an almost circular cylinder, and its length and diameter are 10 cm and 8 cm, respectively. The 2 main characteristics of this artificial heart are that it discharges blood in a pulsatile mode and that it requires no reversing of the motor. Because we have not completed the artificial heart yet, we have tested the eccentric roller mechanism on the prototype with an overflow type mock circulation with a 100 mm Hg afterload. The prototype worked at the roller speeds of 50, 100, and 150 rpm with flow rates of 1.7, 3.7, and 5.4 L/min, respectively. Next the prototype was connected to a Donovan type mock circulatory system and worked at roller speeds of 88–214 rpm with flow rates of 3.0–8.4 Wmin against mean afterloads of 82–120 mm Hg.
Clinical Evaluation of the Centrifugal Pump in Open Heart Surgery: A Comparative Study of Different Pumps
Authors: Takarabe Kyoumi , Yoshikai Masaru , Murayama Junichi , Hamada Masakatsu , Ito Tsuyoshi
Published: November 2008

Abstract: The centrifugal pump is now widely used in open heart surgery for its clinical benefits related to the blood elements and the coagulation system. The purpose of this study was to compare the clinical performances of and the outcomes offered by 4 types of centrifugal pumps. For each pump, we investigated the effects on the blood elements, coagulation system, complements, and immunoglobulins during open heart surgery. Four types of centrifugal pumps were used: the HPM‐15 (Nikkiso Co.), the Capiox (Terumo Co.), the Lifestream (St. Jude Medical Co.), and the BP‐80 (Medtronic, BioMedicus Co.). The platelet count, lactate dehydrogenase (LDH), antithrombin III (AT III), thrombin‐antithrombin complex (TAT), complements (C3, C4, and CH50), and immunoglobulins (IgG, IgA, and IgM) were measured before and after cardiopulmonary bypass (CPB). The platelet count was decreased more significantly by the HPM‐15 than by any of the other pumps. The other parameters showed no difference among the 4 pumps. In clinical use, each of the 4 types of centrifugal pumps was safe.
A Clinical Study for the Durability of Oxygenators on Cardiopulmonary Support
Authors: Usui Akihiko , Murakami Fumihiko , Ooshima Hideki , Tomita Yasuhiro , Yoshida Katsuhiko , Hibi Michiaki , Kawamura Mitsuo , Muras Mitsuya
Published: November 2008

Abstract: Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty‐two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL‐6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than ‐5, blood glutamic‐oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin‐coated system (CB Maxima or AL‐6000 with CB BP‐80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than ‐5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188).
Effective Cross‐Circulation Technique of Venoarterial Bypass for Differential Hypoxia Condition
Authors: Kitamura Masaya , Shibuya Mitsuhiro , Kurihara Hisao , Akimoto Takehide , Endo Masahiro , Koyanagi Hitoshi
Published: November 2008

Abstract: We examined a new technique of cross‐circulation (CC) venoarterial bypass (VAB) with femoral arterial perf usion and superior vena cava drainage through a long femoral venous cannula. Six adult mongrel dogs weighing 15 to 20 kg underwent the CC‐VAB with oxy‐genation after introduction of respiratory failure (RF). The flow of the CC‐VAB was maintained at half the level of the control cardiac output, and the hemodynamic parameters were monitored. To evaluate hypoxia in the upper body, the arterial partial pressure of oxygen (Pao, [mm body, Hg]) in the carotid artery and the venous saturation of oxygen (Svo, [%I) in the pulmonary artery were measured during control, RF, standard VAB, and CC‐VAB conditions. The Pao, decreased significantly after the introduction of RF (41.7 ± 12.4), and it returned to normal levels only after CC‐VAB (151.2 ± 24.5. p > 0.05). The Svo2during CC‐VAB (98.6 ± 2.1) was significantly higher than that during VAB without CC (53.5 ± 3.4, p > 0.05). These results suggest that this cross‐circulation technique could be applied to patients with differential hypoxia during femoral VAB with oxygenation or percutaneous car‐diopulmonary support (PCPS).
Significant Left Ventricular Unloading with Transaortic Catheter Venting During Venoarterial Bypass
Authors: Shibuya Mitsuhiro , Kitamura Masaya , Kurihara Hisao , Kikuchi Chizuo , Endo Masahiro , Koyanagi Hitoshi
Published: November 2008

Abstract: Insufficient unloading of the left ventricle with blood stagnation is a main cause of unsuccessful left vcntricular (LV) recovery during percutaneous cardiopulmo‐nary support (PCPS). The purpose of this investigation was to evaluate the effectiveness of transaortic catheter venting (TACV) for LV unloading. Six adult mongrel dogs (mean weight 16.3 kg, range 14–20 kg) underwent venoarterial bypass (VAB) with TACV. Bypass flow ranged from 0.8–1.2 L/min, and TACV flow ranged from 160–240 ml/min. In addition to monitoring the standard hemodynamic parameters, the slope of the LV end‐systolic pressure‐volume relation (Emax) during transient occlusion of the inferior vena cava, the slope of the LV end‐systolic pressure‐stroke‐volume relation (Ea), the stroke work (SW). the LV pressure‐volume area (PVA), and the slope of the SW end‐diastolic volume relation. the preload recruitable stroke work (PRSW) were assessed by means of a microtip manometer and a conductance catheter. The LV contractility (Emax) and aortic elastance (Ea) were equivalent in the 2 groups with or without TACV (7.7 ± 1.1 versus 8.4 ± 1.5 mm Hg/ml and 8.2 ± 1.4 versus 7.6 ± 1.3 mm Hg/ml). Comparing the measurements for the baseline to those for VAB with TACV, the SW was significantly reduced, and the PVA/SW was increased by TACV (1,685 ± 309 versus 867 ± 188 ± 10‐‐4J, p < 0.05 and 1.32 ± 0.03 versus 1.58 ± 0.11, p < 0.05, respectively). Furthermore, the PRSW was gradually decreased from the baseline value to the value resulting from VAB with TACV (75 ± 8 versus 44 ± 3 ± 10‐‐4J/ml, p < 0.01). In comparison, the percent reduction of SW between VAB and VAB with TACV tended to he increased by TACV (23.2 5 7.2% versus 46.9 ± 7.7%, p = 0.05). These results suggest that TACV might reduce LV work (SW and PRSW) and might increase the LV energetic charge. In conclusion, TACV would be an adjunctive technique to VAB or PCPS for patients with LV failure.
Our Distal Aortic Perfusion System in Descending Thoracic and Thoracoabdominal Aortic Aneurysm Repairs
Authors: Morishita Kiyofumi , Inoue Satomi , Baba Toshio , Sakata Jyun‐ichi , Kazui Teruhisa , Abe Tomio
Published: November 2008

Abstract: We have used heparin‐bonded partial cardio‐pulmonary bypass to support distal aortic circulation during aortic cross‐clamping. However, there were no cardiotomy reservoirs with fully reliable thromboresistance. To resolve this problem, a short‐acting anticoagulant (nafamostat mesilate) was added into a cardiotomy reservoir. The present study was designed to evaluate the efficacy of our distal perfusion system. From May 1995 through the end of May 1996, 27 patients underwent descending thoracic and thoracoabdominal aortic aneurysm repairs with this adjunct, 4 being excluded from the experiment. Twenty patients who had undergone conventional partial cardiopulmonary bypass were defined as the control group. There were no significant differences between the 2 groups in the morbidity, mortality, gas transfer, or transfusion requirements despite the fact that more complicated surgical procedures (shown by a two‐fold increase in the prevalence of reoperation) were required in the group that had received the current distal perfusion adjunct. the heparin‐bonded group. In conclusion, our perfusion system is very effective for descending thoracic and thoracoabdominal aortic aneurysm repairs.
Agreement Between Nosologist and Cardiovascular Health Study Review of Deaths: Implications of Coding Differences
Authors: Ives Diane G. , Samuel Paulraj , Psaty Bruce M. , Kuller Lewis H.
Published: November 2008

OBJECTIVES: To compare nosologist coding of underlying cause of death according to the death certificate with adjudicated cause of death for subjects aged 65 and older in the Cardiovascular Health Study (CHS).

DESIGN: Observational.

SETTING: Four communities: Forsyth County, North Carolina (Wake Forest University); Sacramento County, California (University of California at Davis); Washington County, Maryland (Johns Hopkins University); and Pittsburgh, Pennsylvania (University of Pittsburgh).

PARTICIPANTS: Men and women aged 65 and older participating in CHS, a longitudinal study of coronary heart disease and stroke, who died through June 2004.

MEASUREMENTS: The CHS centrally adjudicated underlying cause of death for 3,194 fatal events from June 1989 to June 2004 using medical records, death certificates, proxy interviews, and autopsies, and results were compared with underlying cause of death assigned by a trained nosologist based on death certificate only.

RESULTS: Comparison of 3,194 CHS versus nosologist underlying cause of death revealed moderate agreement except for cancer (kappa=0.91, 95% confidence interval (CI)=0.89–0.93). kappas varied according to category (coronary heart disease, kappa=0.61, 95% CI=0.58–0.64; stroke, kappa=0.59, 95% CI=0.54–0.64; chronic obstructive pulmonary disease, kappa=0.58, 95% CI=0.51–0.65; dementia, kappa=0.40, 95% CI=0.34–0.45; and pneumonia, kappa=0.35, 95% CI=0.29–0.42). Differences between CHS and nosologist coding of dementia were found especially in older ages in the sex and race categories. CHS attributed 340 (10.6%) deaths due to dementia, whereas nosologist coding attributed only 113 (3.5%) to dementia as the underlying cause.

CONCLUSION: Studies that use only death certificates to determine cause of death may result in misclassification and potential bias. Changing trends in cause‐specific mortality in older individuals may be a function of classification process rather than incidence and case fatality.
Alloimmune response after additional red blood cell antigen challenge in immunized hematooncology patients
Authors: Schonewille Henk , De Vries Rene R.P. , Brand Anneke
Published: November 2008

BACKGROUND: After initial alloimmunization, 20 to 25 percent of immunized nonhematooncology patients develop additional red blood cell (RBC) antibodies after subsequent transfusions. This figure is unknown for hematooncology patients.

STUDY DESIGN AND METHODS: A 24‐year retrospective study was conducted to determine whether RBC‐immunized hematooncology patients differ from other patient cohorts regarding this strong immune response toward additional RBC challenge with clinically relevant RH, KEL, FY, JK, and MNS antigens.

RESULTS: Overall, 25 of 115 immunized patients (21.7%) formed 30 additional antibodies after a median number of 7 RBC units transfused. The median interval between primary and additional antibody detection was 4 months. Diagnosis or treatment intensity did not significantly influence additional antibody development.

CONCLUSION: Additional antibody formation occurs in more than 20 percent of RBC‐alloimmunized hematooncology patients after subsequent transfusions and this is comparable with the frequency in other immunized patients. To avoid extensive RBC alloimmunization, preventive extended antigen matching may be considered in hematooncology patients, who have shown to be capable of antibody formation.
Ten‐year follow‐up of unrelated volunteer granulocyte donors who have received multiple cycles of granulocyte–colony‐stimulating factor and dexamethasone
Authors: Quillen Karen , Byrne Phyllis , Yau Yu Ying , Leitman Susan F.
Published: November 2008

BACKGROUND: The combination of granulocyte–colony‐stimulating factor (G‐CSF) and dexamethasone is an effective granulocyte mobilization regimen. The short‐term side effects of G‐CSF are well studied, but the potential long‐term effects of repeated G‐CSF stimulation in unrelated volunteer granulocyte donors have not been reported.

STUDY DESIGN AND METHODS: Donors who had received G‐CSF three or more times for granulocytapheresis between 1994 and 2002 were identified and attempts were made to contact them if they were no longer active donors. They were matched with control platelet (PLT) donors for sex, age, and approximate number of cytapheresis donations. A health history was obtained and complete blood counts (CBCs) and C‐reactive protein (CRP) determined where feasible.

RESULTS: Ninety‐two granulocyte donors were identified, and 83 of them were contacted. They contributed to 1120 granulocyte concentrates, or a mean of 13.5 granulocytapheresis procedures per donor (and a mean of 87.5 plateletpheresis procedures per donor). There was no difference in CBCs between the granulocyte donors and the control PLT donors. There was no difference in CRP between the two groups, and no difference in pre‐ and post–G‐CSF CRP in a subset of 22 granulocyte donors. Predefined health events included malignancies, coronary artery disease, and thrombosis. At a median 10‐year follow‐up, there were seven such events in the granulocyte donors and five in the PLT donors.

CONCLUSION: Although the number of granulocyte donors studied is small and continued surveillance of healthy individuals after G‐CSF is prudent, our data suggest that G‐CSF/dexamethasone stimulation appears to be safe.
Megaesophagus and Possible Mechanisms of Sudden Death
Authors: Schalinski Sarah , Guddat Saskia S. , Tsokos Michael , Byard Roger W.
Published: November 2008

Abstract:  Achalasia is a neurodegenerative condition characterized by esophageal dysmotility and megaesophagus. Two cases are reported that demonstrate unexpected deaths associated with previously unsuspected achalasia. Case 1: A 66‐year‐old woman was found dead at her home. At autopsy significant stenosing coronary artery atherosclerosis was found with cardiac failure. In addition, a striking finding was narrowing of the distal esophagus with marked proximal dilatation. The esophagus was completely filled with a large amount of soft masticated food and was bulging anteriorly, compressing the left atrium. Death was attributed to ischemic heart disease complicated by previously unsuspected achalasia. Case 2: An 84‐year‐old man collapsed and suffered a respiratory arrest while eating. Internal examination revealed narrowing of the cardioesophageal junction with marked proximal dilatation of the esophagus that contained approximately 50 mL of soft semi‐fluid masticated yellow food paste. Fragments of yellow masticated food remnants were present in upper and lower airways but not within the stomach. There was a history of dementia with symmetrical cerebral ventricular dilatation found at autopsy. Death was attributed to food asphyxia complicating previously unsuspected achalasia with dementia. Megaesophagus may, therefore, be a significant finding at autopsy that may either be a primary cause of unexpected death or else may exacerbate or compound the effects of pre‐existing underlying disease.
Competitive interactions between felid species may limit the southern distribution of bobcatsLynx rufus
Authors: Sánchez‐Cordero Víctor , Stockwell David , Sarkar Sahotra , Liu Hawoei , Stephens Christopher R. , Giménez Joaquín
Published: November 2008

Bobcats are opportunistic felids occurring in a diverse range of habitats and with a widespread distribution from southern Canada to southern Mexico. To explore why the bobcat's distribution stops at the Isthmus of Tehuantepec, we modelled the ecological niches, projected as potential distributions, of the felid community (bobcatLynx rufus, pumaPuma concolor, jaguarPanthera onca, margayLeopardus wiedii, jaguarundiHerpailurus yagouaroundi, and ocelotLeopardus pardalis) in southern Mexico, using occurrence data, environmental maps, the computer algorithm GARP, and a GIS platform. The resulting geographical projection of the ecological niche of bobcats extends south of the Isthmus of Tehuantepec, suggesting that ecological conditions exist for the establishment of populations. The overlap of the modelled distribution of the bobcat was large with that of the puma (97%), but low with that of the ocelot (44%), margay (46%), jaguar (49%), and jaguarundi (52%), the latter three having relatively similar size and feeding habits to bobcats. Moreover, an independent analysis computing a geographic co‐occurrence index showed a similar trend of geographic avoidance (values <−4.60 showing a statistically significant anti‐correlation) between bobcats with the margay, ocelot, jaguarundi, and jaguar, but not with the puma (values >0.15), while all felids, except bobcats, showed a geographic co‐occurrence in southern Mexico (values ranging from −1.91 to 4.71). The Isthmus of Tehuantepec, a lowland region with subtropical habitat, is unlikely to serve as a geographic and ecological barrier to bobcats. As mammal inventories have been conducted for over a century in this region with no records of bobcats, it is unlikely that bobcats are present but have just not been seen. Fossil records also provide no support for the presence of bobcats in that region in the past. Thus, competitive interactions with other felid species appear important in limiting the southern distribution of bobcats, preventing dispersal to a suitable but geographically reduced area south of the Isthmus of Tehuantepec.
Parasite burdens differ between sympatric three‐spined stickleback species
Authors: MacColl Andrew D. C.
Published: November 2008

The ecological theory of adaptive radiation states that differences in ecological circumstances among local populations are the cause of divergence that leads to speciation. The role of parasites in contributing to divergence has seldom been considered, despite their ubiquity and known selective effects. The potential for parasites to contribute to divergence between closely related taxa was examined by quantifying the variation in parasite burdens between sympatric three‐spined stickleback species (Gasterosteus aculeatuscomplex) in two lakes in coastal British Columbia, Canada. In doing so the relative importance of geographical differences between lakes and trophic or microhabitat differences between species within lakes were evaluated. The entire metazoan parasite burdens of a total of 255 limnetic and benthic sticklebacks in Paxton and Priest lakes were assayed over five time points between spring and autumn. Despite their sympatric distributions, there were large differences in parasite burdens between benthic and limnetic sticklebacks within lakes and these were consistent across both lakes. In particular, limnetics suffered greater burdens of the parasitesSchistocephalus solidusandDiplostomum scudderiand benthics had much higher burdens of parasitic glochidia (mollusc larvae). Parasite burdens also differed quantitatively between lakes, but in general such differences were less pronounced than those between the stickleback species. The documented differences in parasite burdens between stickleback species have potential to contribute to divergent selection on life history, immunological and secondary sexual characters that could contribute to reproductive isolation between the species.
Lichens on dead wood: species‐substrate relationships in the epiphytic lichen floras of the Pacific Northwest and Fennoscandia
Authors: Spribille Toby , Thor Göran , Bunnell Fred L. , Goward Trevor , Björk Curtis R.
Published: November 2008

Dead wood is an important habitat feature for lichens in forest ecosystems, but little is known about how many and which lichens are dependent on dead wood. We reviewed substrate use by epiphytic lichens in the combined floras of Fennoscandia and the Pacific Northwest of North America based on literature and herbarium data and analyzed substrate affinity relative to life form, reproductive mode and major phylogenetic group within the floras. A total of 550 (43%) of the 1271 epiphytic species in the combined floras use wood, and 132 species (10%) are obligately associated with dead wood in one or both regions. Obligate and facultative wood‐dwelling guilds in the two floras were strongly similar in terms of internal guild structure in each region, but differ somewhat in species composition, while the bark‐dwelling guild differs strongly in both. Most obligate dead wood users are sexually reproducing crustose lichens. The largest numbers of species are associated with forest structural features such as logs and snags that have been greatly reduced by forest practices. Conservation of lichens inhabiting wood requires greater attention to crustose lichen species and the development of conservation strategies that look beyond numbers and volumes of dead wood and consider biologically meaningful dead wood structure types.
Clinical significance of regulatory T cells in patients with myelodysplastic syndrome
Authors: Hamdi Wedad , Ogawara Hatsue , Handa Hiroshi , Tsukamoto Norifumi , Nojima Yoshihisa , Murakami Hirokazu
Published: November 2008

Objective:  Foxp3+ regulatory T cells (Tregs) play a central role in maintaining immune tolerance. Their expansion in malignant diseases leads to the suppression of host anti‐tumour responses. In this study, we evaluated the clinical significance of Tregs in patients with myelodysplastic syndrome (MDS).

Patients and Methods:  We analysed the number of CD4+ CD25+ Foxp3+ Tregs using three‐colour flow cytometry in the peripheral blood of 26 patients with MDS classified according to the World Health Organization classification method into four cases of refractory anaemia and refractory anaemia with ringed sideroblasts (RA/RARS), 15 cases of refractory cytopenia with multilineage dysplasia (RCMD), three cases of refractory anaemia with excess blast‐1 (RAEB‐1) and four cases of refractory anaemia with excess blast‐2 (RAEB‐2). Eighteen healthy volunteers were included as the control group.

Results:  The mean absolute numbers of Tregs in the RA/RARS group (0.06 × 109/L; 95% CI, 0.02–0.10 × 109/L) and RAEB group (0.06 × 109/L; 95% CI, 0.02–0.10 × 109/L) were significantly higher than that of the control group (0.03 × 109/L; 95% CI, 0.02–0.03 × 109/L) (P < 0.05). However, in the RCMD group, there was no significant difference in the mean absolute number of Tregs (0.03 × 109/L; 95% CI, 0.02–0.04 × 109/L) compared with the control group. Regarding the mean level of the CD8/Foxp3 ratio, there were significant decreases in the RA/RARS group (2.8; 95% CI, 0.7–4.9; P < 0.01), RCMD group (3.4; 95% CI, 2.0–4.4; P < 0.001) and RAEB group (2.1; 95% CI, 1.7–2.5; P < 0.001) compared with the control group (6.1; 95% CI, 5.1–7.0).

Conclusions:  The expansion of natural CD4+ Tregs may contribute to the suppression of CD8 through the Th1‐mediated immune response in MDS. The low CD8/Foxp3 ratio is a characteristic feature in MDS. To determine whether the expansion of CD4+ Tregs contributes to the progression of MDS subtypes into more aggressive subtypes, more MDS cases and further follow‐up are required.
Effect of cannabis usage on the oral environment: a review
Authors: Versteeg PA , Slot DE , Van Der Velden U , Van Der Weijden GA
Published: November 2008

Abstract:  Aim:  To evaluate oral environmental changes in cannabis users.

Material and Methods:  The MEDLINE and Cochrane Central register of controlled trails (CENTRAL) were searched up to April 2007 to identify appropriate studies.

Results:  Independent screening of 982 titles and abstracts (MEDLINE‐Pubmed) and (Cochrane) papers resulted in seven eligible publications.

Conclusion:  Based on the limited data, it seems justified to conclude that with increasing prevalence of cannabis use, oral health care providers should be aware of cannabis‐associated oral side effects, such as xerostemia, leukoedema and an increased prevalence and density of Candida albicans.
Clinical evaluation of brushing time and plaque removal potential of two manual toothbrushes
Authors: Terézhalmy GT , Biesbrock AR , Walters PA , Grender JM , Bartizek RD
Published: November 2008

Abstract:  Aim:  To compare plaque removal efficacy of Oral‐B CrossAction (CA) used for 1 min with an American Dental Association (ADA) manual toothbrush used for 2 or 5 min in an examiner‐blind, three‐treatment, six‐period crossover study.

Materials and methods:  After refraining from all oral hygiene procedures for 23–25 h, subjects were randomly assigned to one of nine possible six‐period (visit) treatment sequences. Plaque was assessed at baseline (Rustogi Modified Navy Plaque Index). Post‐brushing scores were recorded after brushing with a marketed dentifrice and the assigned toothbrush for the specified duration. The same procedure was followed at each of six subsequent visits. Clinical measurements were carried out by the same examiner.

Results:  Forty subjects completed the study. All three treatments effectively removed plaque from the whole mouth, along the gingival margin and from approximal surfaces. Whole mouth and gingival margin plaque removal scores with CA for 1 min did not differ significantly from scores with the ADA toothbrush used for 2 min. The ADA brush used for 5 min showed significantly greater whole mouth (P < 0.001) and gingival margin (P < 0.001) plaque reduction than the two other treatments. Approximal plaque removal scores did not differ between the three treatments. Conclusions: Efficient plaque removal can be achieved after 1 min of brushing with CA. The amount of plaque removed did not differ significantly from that achieved with the ADA brush after 2 min of brushing. Greater whole mouth and gingival margin plaque removal scores were seen with the ADA brush after 5 min.
Oral self‐care habits of dental and healthcare providers
Authors: Zadik Y , Galor S , Lachmi R , Proter N
Published: November 2008

Abstract:  Objective:  To evaluate the self‐care level of dental and healthcare providers regarding prevention of oral diseases

Methods:  Healthcare providers (dental assistants and surgeons, laboratory personnel, biologists, medics, paramedics, corpsmen, nurses, pharmacists, physicians, physiotherapists, psychologists, social workers, speech therapists, X‐ray technicians) and non‐health care providing adults (the general population) were asked to respond to a questionnaire regarding their routine measures for maintaining oral health

Results:  Three hundred and twenty‐six healthcare providers and 95 non‐healthcare providers participated in the study. Regarding toothbrushing, flossing, undergoing periodic dental examinations and professional scaling/polishing, dental practitioners have better, but not perfect, maintenance habits than other healthcare providers. Non‐dental healthcare providers have better dental habits than the general population, and nurses and medical practitioners have better dental habits than medics, paramedics, corpsmen and para‐medical professionals. Among non‐dental healthcare providers, nurses have a relatively high frequency of toothbrushing and flossing but a low frequency of periodic examinations and scaling/polishing. Generally, females reported significantly higher frequencies of toothbrushing and flossing than males did. The toothpaste selection of the participants was primarily influenced by dentists’ recommendations, the flavour of the toothpaste, and its anti‐malodour effect were the most dominant factors.

Conclusion:  The compliance of health professionals, especially dental practitioners, with appropriate oral health measures is relatively high. However, the dental team cannot always assume that the dental patient, who also happens to be a healthcare provider, has meticulous oral habits. The dental hygienist and surgeon have to educate and motivate their patients, especially healthcare providers because of the influence of the latter on their own patients.
The efficacy of dental floss in addition to a toothbrush on plaque and parameters of gingival inflammation: a systematic review
Authors: Berchier CE , Slot DE , Haps S , Van der Weijden GA
Published: November 2008

Abstract:  Objectives:  The aim of this study was to assess systematically the adjunctive effect of both flossing and toothbrushing versus toothbrushing alone on plaque and gingivitis.

Materials:  The MEDLINE and Cochrane Central register of Controlled Trials (CENTRAL) databases were searched through December 2007 to identify appropriate studies. The variables of plaque and gingivitis were selected as outcomes.

Results:  Independent screening of titles and abstracts of 1166 MEDLINE–Pubmed and 187 Cochrane papers resulted in 11 publications that met the eligibility criteria. Mean values and SD were collected by data extraction. Descriptive comparisons are presented for brushing alone or brushing and flossing. A greater part of the studies did not show a benefit for floss on plaque and clinical parameters of gingivitis. A meta‐analysis was performed for the plaque index and gingival index.

Conclusions:  The dental professional should determine, on an individual patient basis, whether high‐quality flossing is an achievable goal. In light of the results of this comprehensive literature search and critical analysis, it is concluded that a routine instruction to use floss is not supported by scientific evidence.
Efficacy of triazoles and strobilurins in controlling black spot disease of roses caused by Diplocarpon rosae
Authors: Gachomo E.W. , Dehne H.‐W. , Steiner U.
Published: November 2008

Black spot disease is an important disease of roses with worldwide occurrence. It is caused by Diplocarpon rosae, an ascomycetous fungus and its control relies on fungicides. The effects of strobilurins and triazoles on D. rosae development within the host and on disease symptoms have not been well studied. Strobilurins completely inhibited germination of conidia when applied protectively 1 week before inoculation or on the same day with the inoculum. They were, however, not effective in eradicating the disease when applied after the fungus was established in the host. Triazoles reduced the germination rate of the conidia when applied protectively and they inhibited disease symptom development when applied after the fungus was established in the host but before symptom expression. Application of triazoles after symptom development suppressed further development of the disease, but in the case of treatment with myclobutanil yellowing and defoliation still occurred. Post‐infection application of triazoles led to the apparent breakdown of subcuticular mycelia, intercellular mycelia, and hyphae in the epidermal cells, while the effects of strobilurins were limited to the subcuticular mycelia. Triazoles were more effective than strobilurins because they are more systemic.
Vegetation Mapping of the Mond Protected Area of Bushehr Province (South‐west Iran)
Authors: Mehrabian Ahmadreza , Naqinezhad Alireza , Mahiny Abdolrassoul Salman , Mostafavi Hossein , Liaghati Homan , Kouchekzadeh Mohsen
Published: November 2008

Arid regions of the world occupy up to 35% of the earth's surface, the basis of various definitions of climatic conditions, vegetation types or potential for food production. Due to their high ecological value, monitoring of arid regions is necessary and modern vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south‐west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps. Sixteen map units covering 12 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata, Salicornia europaea‐Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced.
Effects of Irradiance and Temperature on the Photosynthesis and Vegetative Propagation of Caulerpa serrulata
Authors: Li Demao , Wang Guangce , Chen Limei , Lü Fang , Shen Zonggen
Published: November 2008

The photosynthetic oxygen evolution of Caulerpa serrulata was determined with oxygen electrodes. The effects of light and temperature on the growth and regeneration of fragmented C. serrulata thalli were analyzed. The regenerating rate and establishment of different sizes and portions of C. serrulata were studied. The results showed that the light saturation point of C. serrulata was 200 μmol photons/m2 per s and the optimum growth temperature was 25–30 °C. Under these conditions, the maximum photosynthetic oxygen evolution rate was 15.1 ± 0.29 mg O2/mg Chl a/h, the growth rate and elongation rate reached the highest values, 4.67 ± 0.09 mg FW/d and 0.78 ± 0.01 mm/d, respectively. The fragmented C. serrulata thalli was regenerated at 20–35 °C and survived at 15 °C and 200 μmol photons/m2 per s. A different survival rate was detected according to fragment size. All of these results indicated that C. serrulata was a candidate to become an invasive species if introduced into a new place. Therefore, we should pay more attention to C. serrulata for its potential threat to marine ecosystem when it is sold for aquarium use.
Accumulation and Dynamic Trends of Triterpenoid Saponin in Vegetative Organs of Achyranthus bidentata
Authors: Li Jinting , Hu Zhenghai
Published: November 2008

The relationship between structural features of various vegetative organs and triterpenoid saponin accumulation in Achyranthus bidentata Blume was investigated using anatomy, histochemistry and phytochemistry. The results showed that the primary and secondary structures of roots, and the structures of stems and leaves of A. bidentata, were similar to those of ordinary dicotyledonous plants. The enlargement of its roots, however, was primarily associated with growth and differentiation of tertiary structures. There were collateral medullary vascular bundles in addition to the normal vascular bundles in the stem. The tertiary structure was not only main parts in the roots of A. bidentata, but also important storage region of triterpenoid saponin in its growth and development. The stem may be the essential transport organ of triterpenoid saponin, while palisade parenchyma may be the primary synthesis location. In November, the total quantity of triterpenoid saponin and overall biomass in the roots reach a maximum level. This was the best time, therefore, to harvest the roots and corresponded to the traditional harvest period. Despite the withered appearance of leaves, stems also contained substantial amounts of triterpenoid saponin, and it was recommended that the stems of A. bidentata should be used.