bluuebunny/crossref_metadata_2025 huggingface dataset:
Helicobacter pyloriInfection and Recurrent Abdominal Pain in Turkish Children
Authors: Özen Hasan , Dinler Gönül , Akyön Yakut , Koçak Nurten , Yüce Aysel , Gürakan Figen
Published: March 2003

Background.Helicobacter pyloriinfection is primarily acquired in childhood. However, the association betweenH. pyloriinfection and recurrent abdominal pain (RAP) remains unclear.

Materials and methods.One hundred and forty‐one children with and 21 without RAP underwent upper gastrointestinal endoscopy. At least five antral gastric biopsies were obtained from each patient and the presence ofH. pyloriinfection was accepted when at least two out of four tests (histology, direct antral smear, culture, and rapid urease test) were positive. Patients withH. pyloriinfection underwent triple therapy with omeprazole, clarithromycin, and metronidazole.

Results.Eighty‐five out of 141 (60.3%) patients with RAP wereH. pyloripositive whereas 5 out of 21 (20.8%) patients without RAP were (p = .0037). Symptoms were disappeared in 87% of children whoseH. pyloriinfection was eradicated compared with 41% of those in whom the infection was not eradicated (p = .0035).

Conclusions.It was concluded that children with RAP andH. pyloriinfection appear to benefit from eradication therapy in Turkey.
Helicobacter pylori Infection is Associated with a Decreased Risk of Developing Oesophageal Neoplasms
Authors: Henrik Simán J. , Forsgren Arne , Berglund Göran , Florén Claes‐Henrik
Published: March 2003

Background.

The role of Helicobacter pylori infection in the development of oesophageal malignancies was investigated through a multivariate conditional logistic regression analysis in a nested case‐control study.

Methods.

Blood samples and a questionnaire on smoking and alcohol habits were collected from a cohort of 32,906 city residents during a health‐screening programme between 1974 and 1992. Forty‐four cases of oesophageal cancer and 149 matched controls were selected. The mean interval between screening and cancer diagnosis was 11.9 years. H. pylori seropositivity was determined by an enzyme‐linked immunosorbant assay measuring IgG. Occupation was included in the statistical analysis as an indicator of socio‐economic status.

Results.

Helicobacter pylori seropositivity was present in 10 of the cases (22.7%) and 67 of the controls (45.0%). In a multivariate model, with adjustment for occupation, tobacco and alcohol consumption, the odds ratio for developing an oesophageal malignancy when infected with H. pylori was 0.29 (95% confidence interval (CI): 0.12–0.67). Current smokers had an odds ratio of 17.3 (95% CI: 3.0–99.4) and the odds ratio for ex‐smokers was 5.9 (95% CI: 1.15–29.9). High alcohol consumption was no longer significantly associated with oesophageal neoplasms after tobacco smoking was included into the model, odds ratio 1.22 (95% CI: 0.46–3.2). The protective effect of H. pylori was more pronounced for oesophageal adenocarcinoma (seven cases, odds ratio 0.16, 95% CI: 0.00–1.06) than for squamous‐cell carcinoma (29 cases, odds ratio 0.41, 95% CI: 0.14–1.2).

Conclusions.

Helicobacter pylori infection is associated with a decreased risk of developing an oesophageal malignancy. Current smokers and ex‐smokers have instead a definite increased risk of oesophageal neoplasms.
Proteome Analysis of Highly Immunoreactive Proteins of Helicobacter pylori
Authors: Lock Robert A. , Coombs Geoffrey W. , McWilliams Tracy M. , Pearman John W. , Grubb Warren B. , Melrose Graham J. H. , Forbes Geoffrey M.
Published: March 2003

Background. Identification of the immunoreactive proteins of Helicobacter pylori is important for the development of both diagnostic tests and vaccines relating to the organism. Our aim was to determine whether there are significant differences between human IgG and IgA reactivities to individual H. pylori proteins, and whether patterns of immunoreactivity are sustained across different strains of H. pylori.

Method. The total complement of protein from seven strains of H. pylori was resolved by two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE). Proteins were transferred electrophoretically onto polyvinylene difluoride (PVDF) membranes, which were probed with sera pooled either from H. pylori‐infected patients, or noninfected (control) patients. Highly immunoreactive proteins were detected using chromogenic enzyme‐antibody conjugates recognising either serum IgG or IgA. These proteins were then characterised by tryptic peptide‐mass fingerprinting using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS).

Results. Highly immunoreactive proteins were detected which were common to all seven strains, and recognised by both immunoglobulin subclasses. The proteins appear to be localised in five groups. Protein analysis established that these groups encompass multiple isoforms of chaperonin HspB (two subgroups); urease β‐subunit UreB; elongation factor EF‐Tu; and flagellin FlaA. The pattern of highly immunoreactive proteins was strongly conserved across the seven strains.

Conclusion. These results suggest that within a tightly defined region on the H. pylori proteome map there are five groups of proteins that are highly reactive to both IgG and IgA. Our analysis suggests it is unlikely that the highly immunoreactive clusters harbour any significant proteins other than isoforms of HspB, UreB, EF‐Tu and FlaA, and that, with the partial exception of FlaA, these clusters are strongly conserved across all seven strains.
Molecular Typing of Helicobacter pylori by Virulence‐Gene Based Multiplex PCR and RT‐PCR Analysis
Authors: Monstein Hans‐Jürg , Ellnebo‐Svedlund Katarina
Published: March 2003

Background. In recent years, numerous PCR amplification typing methods have been developed for the identification of H. pylori specific virulence genes. To reduce the number of PCR amplifications needed we have previously developed virulence gene based multiplex PCR and RT‐PCR assays.

Aim. The aim of the present study was to characterise Helicobacter pylori strains by means of virulence‐gene based multiplex PCR and reverse‐transcription PCR.

Subjects. Helicobacter pylori clinical reference strains HP‐HJM 1–25 originally obtained from routine cultures of clinical gastric biopsy specimens from dyspeptic patients were used in the present study.

Methods. Helicobacter pylori multiplex PCR and RT‐PCR assays were carried out using primer pairs targeting the cagA, vacA, ureA, ureI, hspA (hsp60), and sodB genes and their cDNA.

Results. Unexpected multiplex PCR and RT‐PCR patterns were observed by ethidium bromide staining of agarose gels and Southern blot hybridisation analysis. DNA sequence analysis revealed a complex pattern of point mutations, deletions and insertions in the sodB, cagA and vacA genes, respectively. Mutations occurring in the PCR and hybridisation primer binding sites might explain some of the discrepancies previously observed in the expression of these genes. Furthermore, the present data show that coexpression of cagA and vacA transcripts of different sizes may take place in the same strain.

Conclusions. The multiplex PCR and RT‐PCR assay described allows rapid characterisation of H. pylori virulence genes at the DNA and RNA (cDNA) levels. However, extensive DNA sequence analysis seems necessary if one wants to reveal details of mutations occurring in the cagA and vacA genes.
A Case of Acute Gastric Mucosal Lesions Associated with Helicobacter heilmannii Infection
Authors: Yoshimura Masaya , Isomoto Hajime , Shikuwa Saburo , Osabe Masayuki , Matsunaga Keiichiro , Omagari Katsuhisa , Mizuta Yohei , Murase Kunihiko , Murata Ikuo , Kohno Shigeru
Published: March 2003

A 69‐year‐old‐woman presented with acute epigastric pain, nausea, vomiting and heartburn. Endoscopy disclosed acute gastric mucosal lesions including mucosal edema, erosions, and ulcers with blood crusts in the antrum. Touch cytology and histological assessment obtained from the affected mucosa revealed acute neutrophilic gastritis and single longer and more coiled organisms than Helicobacter pylori, suggesting Helicobacter heilmannii. Electron micropragh confirmed the characteristic morphology. Despite a positive rapid urease test, H. pylori was not isolated by culture or detected by histology and Gram smears. Based on these findings, a diagnosis of acute gastric mucosal lesions associated with H. heilmannii infection was established. This was successfully treated with a 2‐week triple therapy consisting of lansoprazole, clarithromycin and metronidazole with persistent endoscopic and histological remission. This is a rare case of H. heilmannii‐associated acute gastric mucosal lesions, diagnosed by morphology using touch cytology and histology. The patient might benefit from antimicrobial treatment employing the regimen effective for H. pylori.
Perceived Risk of Breast Cancer
Authors: Facione Noreen C.
Published: March 2003

purpose: The purpose of this study was to examine the influence of heuristic reasoning on women's perceived risk for developing breast cancer, and to test for an expected bias in the direction of optimism that is predicted by recent research on human cognition.

description of study: In total, 770 women recruited in community settings were surveyed regarding cancer screening behavior and their perceived risk of developing breast cancer.

results: Most women perceived their risk of breast cancer to be lower than that of other women (3:1), confirming the expected bias toward optimism, and this finding was not attributable to the personality trait of optimism. Women following mammography guidelines showed greater optimism that their risk was low. Cancer knowledge and education diminished unwarranted optimism. Women with a history of benign breast disease, with a female relative with breast cancer, or both overestimated their risk. All findings suggest that heuristic thinking is being used to estimate personal cancer risk.

clinical implications: Clinicians should expect women to be optimistic about their personal risk of developing breast cancer. As a result, women may put off breast cancer screening or delay the evaluation of breast symptoms that may signal breast cancer. Helping women to understand their relative risk is an essential part of a health promotion visit.
Of coiled oysters and big brains: how to rescue the terminology of heterochrony, now gone astray
Authors: Gould Stephen Jay
Published: March 2003

SUMMARY During the past decade, the terminology of heterochrony, heretofore consistent and workable, has become internally illogical and incoherent as the unfortunate result of an extension of terms, properly devised to describe shifts in developmental timing of shapes and features, to the rates and timings that cause these shifts. All the resulting, and extensive, confusion in the literature arises as a pure consequence of this error in logic and nomenclature, and not at all from disagreement about the important empirical questions described by this central concept and phenomenon in the integration of evolution and development. In particular, the claim that the same feature in human evolution (the paedomorphic shape of the human cranium) expresses either neoteny or the apparently opposite phenomenon of hypermorphosis only records the terminological error, and not any factual disagreement—for this neotenic feature has probably arisen by a prolongation of juvenile growth patterns inappropriately designated as “hypermorphosis of rate.” I show that a prominent and unchallenged case of neoteny in fossil oysters arises by exactly the same evolutionary mode. When we restore the terminology of heterochrony by the “paedomorphic” intellectual event of dropping these inadaptive terminal accretions (the illogical extension of shape categories to describe rates), then the concept of heterochrony will again make proper distinctions by designating a clearly meaningful category of evolutionary changes originating by shifts in timing for features already present in ancestors. “It's not all heterochrony”—and this particular statement of “less is more” represents heterochrony's strength as an interesting subset with definite meaning, rather than an illogical hodge‐podge apparently applicable to all phenomena, and therefore explaining nothing.
Ontogeny and homoplasy in the papionin monkey face
Authors: Collard Mark , O'Higgins Paul
Published: March 2003

SUMMARYRecent molecular research has provided a consistent estimate of phylogeny for the living papionin monkeys (Cercocebus,Lophocebus,Macaca,Mandrillus,Papio, andTheropithecus). This phylogeny differs from morphological phylogenies regarding the relationships of the mangabeys (CercocebusandLophocebus) and baboons (Mandrillus,Papio, andTheropithecus). Under the likely assumption that the molecular estimate is correct, the incongruence between the molecular and morphological data sets indicates that the latter include numerous homoplasies. Knowledge of how these homoplasies emerge through development is important for understanding the morphological evolution of the living papionins, and also for reconstructing the phylogenetic relationships and adaptations of their fossil relatives. Accordingly, we have used geometric morphometric techniques and the molecular phylogeny to investigate the ontogeny of a key area of morphological homoplasy in papionins, the face. Two analyses were carried out. The first compared allometric vectors ofCercocebus,Lophocebus,Macaca,Mandrillus, andPapioto determine which of the facial resemblances among the genera are homoplasic and which are plesiomorphic. The second analysis focused on early post‐natal facial form in order to establish whether the facial homoplasies exhibited by the adult papionins are to some degree present early in the post‐natal period or whether they develop only later in ontogeny. The results of our analyses go some way to resolving the debate over which papionin genera display homoplasic facial similarities. They strongly suggest that the homoplasic facial similarities are exhibited byMandrillusandPapioand not byCercocebusandLophocebus, which share the putative primitive state withMacaca. Our results also indicate thatMandrillusandPapioachieve their homoplasic similarities in facial form not through simple extension of the ancestral allometric trajectory but through a combination of an extension of allometry into larger size ranges and a change in direction of allometry away from the ancestral trajectory. Thus, the face ofMandrillusis not simply a hypermorphic version of the face of its sister taxon,Cercocebus, and the face ofPapiois not merely a scaled‐up version of the face of its sister taxon,Lophocebus. Lastly, our results show that facial homoplasy is not restricted to adult papionins; it is also manifest in infant and juvenile papionins. This suggests that the homoplasic facial similarities betweenMandrillusandPapioare unlikely to be a result of sexual selection.
Correlations between scale structure and pigmentation in butterfly wings
Authors: Janssen Jeroen M. , Monteiro Antónia , Brakefield Paul M.
Published: March 2003

SUMMARY We examined the correlation between color and structure of wing scales in the nymphalid butterflies Bicyclus anynana and Heliconius melpomene. All scales in B. anynana are rather similar in comparison to the clear structural differences of differently pigmented scales in H. melpomene. Where scale structural differences in H. melpomene are qualitative, they seem to be quantitative in B. anynana. There is a “gradient” in the density of some structural elements, the cross ribs, in the scales of B. anynana: black, gold, and brown scales show progressively lower cross rib density within an individual. There is, however, high individual variation in the absolute cross rib densities (i.e., scales with a particular color and cross rib density in one individual may have a different color but similar density in another individual). By ectopically inducing color pattern during early pupal development, we examined whether a scale's color and its microstructure could be uncoupled. The effect of these manipulations appears to be different in B. anynana and H. melpomene. In Bicyclus, “black” scales induced by wing damage at an ectopic location normally containing brown scales acquire both an intermediate structure and color between that of brown and normal black scales. In Heliconius, however, intermediate colors or scale structure were never observed, and scales with an altered color (due to damage) always have the same structure as normal scales with that color. The results are discussed on the basis of gene expression patterns, variability in rates of scale development and pigment, and scale sclerotization pathways.
The pattern of segment formation, as revealed by engrailed expression, in a centipede with a variable number of segments
Authors: Kettle Chris , Johnstone Jenni , Jowett Trevor , Arthur Helen , Arthur Wallace
Published: March 2003

SUMMARY Arthropods vary enormously in segment number, from less than 20 to more than 200. This between‐species variation must have originated, in evolution, through divergent selection operating in ancestral arthropod species with variable segment numbers. Although most present‐day arthropod species are invariant in this respect, some are variable and so can serve as model systems. Here, we describe a study based on one such species, the coastal geophilomorph centipede Strigamia maritima. We investigate the way in which segments are formed using in situ hybridization to demonstrate the expression pattern of the engrailed gene during embryogenesis. We also analyze segment number data in mother–offspring broods and thereby demonstrate a significant heritable component of the variation. We consider how natural selection might act on this intraspecific developmental variation, and we discuss the similarities and differences in segment formation between the geophilomorphs and their phylogenetic sister‐group.
The Safety System for the Rotary Blood Pump, Combination of the Valve and LVAD Pulsatile Mode: In Vitro Test
Authors: Tayama Eiki , Ohashi Yukihiko , Niimi Yoshinari , Takami Yoshiyuki , Ohtsuka Goro , Nakata Kin‐ichi , Benkowski Robert , Glueck Julia A. , Nosé Yukihiko
Published: March 2003

The significant amount of regurgitation produced by a stopped rotary blood pump is one of the major considerations for its use as an implantable left ventricular assist device (LVAD), especially if the pump accidentally stops. The installation of a valve is an option for the solution of this potential problem. However, this option may lead to thrombogenic problems, particularly if the valve motion is restricted. This in vitro study analyzes the valve performance and assesses the credibility of a rotary blood pump valve. A pulsatile pump was used as the natural heart and a centrifugal pump as the LVAD. The valve was positioned into the LVAD outflow. In the low speed range (<1,000 rpm in this test condition), normal valve motion was maintained. Also, the valve model provided a higher mean bypass flow than the model without a valve due to reduced regurgitation. However, the valve motion was drastically restricted when in the high speed range (>1,600 rpm in this condition). The pulsatile mode was applied to the LVAD by periodically changing the impeller speed (40 bpm); subsequently, a constant valve motion could be provided. A possibility exists that this pulsatile mode application could eliminate thrombosis formation around the valve. A conclusion was made that the combination of a valve and an LVAD in a pulsatile mode is considered to be a unique safety system for a rotary blood pump.
Effects of the External Qigong on Symptoms of Arteriosclerotic Obstruction in the Lower Extremities Evaluated by Modern Medical Technology
Authors: Agishi Tetsuzo
Published: March 2003

The modern treatment strategy for arteriosclerotic obstruction (ASO), which symptomatically appears primarily in the lower extremities, consists of drug and interventional therapy. Reported herein are the effects of external qigong, which has been a traditional therapeutic technique in the oriental countries for a long time and is known to bring warmness in the body, evaluated by modern medical technology.
Prolonged Nonpulsatile Left Heart Bypass with Reduced Systemic Pulse Pressure Causes Morphological Changes in the Aortic Wall
Authors: Nishimura Takashi , Tatsumi Eisuke , Takaichi Shigeko , Taenaka Yoshiyuki , Wakisaka Yoshinari , Nakatani Takeshi , Masuzawa Toru , Takewa Yoshiaki , Nakamura Makoto , Endo Seiko , Nakata Masako , Takano Hisateru
Published: March 2003

Abstract We investigated the morphological changes in the aorta due to reduced systemic pulse pressure in prolonged nonpulsatile left heart bypass (LHB). Nineteen adult goats were divided into 3 groups, the nonpulsatile group in which nonpulsatile LHB was conducted, the pulsatile group in which pulsatile LHB was conducted, and the control group used as the normal control. The average aortic pulse pressures were 12, 47, and 37 mm Hg, respectively. The descending aorta was subjected to morphological examination. In the nonpulsatile group, the wall was significantly thinner, and the volume ratio of smooth muscle cells (SMCs) was much lower. In terms of the SMC type classification, the proportion of SMCs with low activity and low contractility was higher, and the cell density of the SMCs was increased compared to those in the other groups. These results indicate that prolonged nonpulsatile LHB causes morphological atrophic changes in the aorta.
Left Heart Bypass Using the Oscillated Blood Flow with Totally Implantable Vibrating Flow Pump
Authors: Yambe Tomoyuki , Owada Naoki , Kobayashi Shin‐ichi , Sonobe Taro , Naganuma Shigeru , Nanka Shunsuke , Hashimoto Hiroyuki , Yoshizawa Makoto , Tabayashi Kou‐ichi , Takayasu Hideki , Takeda Hiroshi , Nitta Shin‐ichi
Published: March 2003

Abstract Aiming at a totally implantable ventricular assist device (VAD), a vibrating flow pump (VFP) was developed in Tohoku University. A transcutaneous energy transmission system (TETS) using an amorphous fiber was developed for the totally implantable VAD system. The VFP works with a higher frequency than the natural heart of a biological system, a frequency of 10–50 Hz. In this research, animal experiments on left heart bypass were performed with healthy goats. Blood from the apex of the left ventricle was received and was sent to the aorta so that an adequate supporting effect of the left heart was provided. In particular, the depression effect of the left ventricle was obvious. As a result, sufficient artificial heart flow was provided. For a totally implantable type VAD, left heart bypass of almost 100% may become necessary in some situations. Therefore, apex approaches of left heart bypass may be desirable. From an anatomical consideration, an apex of the heart is suitable for the VFP of this totally implantable type. In the left heart bypass for which the apex of the heart was used, an almost 100% bypass was possible. This is a requirement that is important when waiting for recovery of sufficient cardiac function. It is also important that left heart circulation is maintained fully by an artificial heart of the complete implantation type. The VFP was considered to be useful as a totally implantable type artificial heart from the results.
Less Invasive Coronary Artery Bypass Without Cardiopulmonary Bypass
Authors: Shiono Motomi , Sezai Yukiyasu
Published: March 2003

Minimally invasive coronary artery bypass grafting (CABG) aims to avoid cardiopulmonary bypass and take maximum advantage of a smaller incision. Minimally invasive direct coronary artery bypass (MIDCAB) surgery is performed on selected arteries of the beating heart under direct vision through a choice of small incisions. Short‐term results show good patency rates and a dramatic impact in terms of shorter hospital stays and cost effectiveness. The procedure is also being used increasingly in Japan. However, valid concerns have been raised about the quality of the anastomosis fashioned on a beating heart with pharmacologic bradycardia, and the long‐term result of this technique is still questionable. The combined use of circulatory assist devices and mechanical stabilizing devices will be expected to expand access to coronary arteries by allowing for decompression of the left ventricle, permitting retraction and rotation of the heart, and hopefully further improvement of the results. Less invasive coronary surgery should be proven to be as effective and safe as conventional CABG before widespread adoption.
Substitution of Acetic Acid for Hydrochloric Acid in the BicarbonateBuffered Dialysate
Authors: Fournier Gilles , Potier Jacky , Thébaud Henri‐Emile , Majdalani Ghandour , Ton‐That Hung , Man Nguyen‐Khoa
Published: March 2003

Abstract: In a multicenter study including 5 dialysis units, blood acetate changes during 4 h dialysis sessions in 141 patients treated with a 4 mM acetate‐containing bicarbonate dialysate (ABD) were evaluated and compared to the values of 114 patients using an acetate‐free bicarbonate dialysate (AFD). Acetate‐free bicarbonate dialysate was delivered by a dialysis machine from the mixing with water for dialysis of a 1/26.2 bicarbonate concentrate, and a 1/35 acid‐concentrate in which acetic acid was substituted for hydrochloric acid (Soludia, Fourquevaux, France). This new type of dialysate was routinely in use for 3 years on average (range, from 2 to 5 years). All patients fasted before and during dialysis. Blood samples were withdrawn at the start and at the end of dialysis sessions. The acetate plasma concentration was determined using the acetyl‐CoA synthetase enzymatic method (Boehringer, Manheim, Germany). In patients treated with ABD whose predialysis blood acetate levels were in the physiologic range of ≤100 μM (n = 113), the acetate plasma concentration increased from a predialysis mean value of 22 ± 3 μM to a postdialysis mean value of 222 ± 11 μM in 88 patients (78% of patients) whereas the acetate plasma concentration changes remained in the range of physiologic values from 21 ± 6 to 58 ± 7 μM in the other 25 patients. In contrast, patients treated with AFD whose predialysis blood acetate levels were in the physiologic range (n = 108), acetate plasma concentration increased from a predialysis mean value of 49 ± 6 μM to 160 ± 19 μM in only 13 patients (12% of patients) whereas acetate plasma concentration changes remained in the range of physiologic values of 23 ± 2 to 41 ± 3 μM in most of the patients of this group. In this study, a significant number of patients, whether receiving standard or acetate‐free bicarbonate dialysates, exhibited an extremely high acetate plasma concentration at the start of the dialysis session. Hyperacetatemia was controlled with AFD in patients whose predialysis acetate plasma concentration of 316 ± 82 decreased to 55 ± 23 μM (n = 6) at the end of the dialysis session whereas the acetate plasma concentration remained high when the predialysis concentration was 580 ± 76 μM, with a postdialysis concentration of 233 ± 39 μM (n = 28). It is concluded that in patients whose predialysis blood acetate levels were in the physiologic range, acetate‐containing bicarbonate dialysate induces hyperacetatemia whereas postdialysis blood acetate remains in the normal range in such dialysis patients treated with acetate‐free dialysate. Chronic hyperacetatemia, which could be found in dialysis patients, is well controlled by dialysis using an acetate‐free dialysate.
My Life with Dr. Willem Kolff
Authors: Nosé Yukihiko
Published: March 2003

Since 1957, I have been well aware of Dr. Kolff's contribution in the field of artificial organs. Therefore, when I came to the United States, the first thing I knew I wanted to do was to meet Dr. Kolff. I finally met him on April 16, 1962 in Cleveland. At that time, I never dreamed that one day I would be working for him even though I had already been involved in the field of artificial organs. During the 3 years that I worked for Dr. Kolff, between April 1, 1964 and March 31, 1967, I obtained the basic training and foundation for succedding him in the Department of Artificial Organs, Cleveland Clinic Foundation. During those first 10 years after succeeding Dr. Kolff, I devoted myself to reestablishing the department. He was always supportive of me in establishing my objective. Beginning in 1977, together with Dr. Kolff, I devoted my life to establishing and maintaining the International Society for Artificial Organs (ISAO) as the leading organization in the world for artificial organ technologies. Dr. Kolff was also supportive of this effort. Without his support, I, as well as others in the world who are involved in artificial organ technologies, believe that the ISAO would not be what it is today. We are very grateful to him for his contributions in this field.
Implantation of the Undulation Pump Total Artificial Heart in the Goat
Authors: Abe Yusuke , Chinzei Tsuneo , Ono Toshiya , Mochizuki Shuichi , Saito Itsuro , Guba Peter , Karita Tatsuro , Sun Yan pin , Kouno Akimasa , Isoyama Takashi , Baba Kazunori , Imachi Kou
Published: March 2003

Abstract: The undulation pump total artificial heart (UPTAH) was developed by using small‐size continuous‐flow displacement‐type blood pumps (undulation pump). To clarify and improve the problems accompanied by the implantation in the chest, 14 animal experiments were performed on goats weighing 41.3–79.2 kg. The UPTAH could be implanted in the chest of all goats and was driven with a modulation pulsatile mode. The first problem was the atrial suction effect. This problem could be prevented to some extent by developing the soft disk and by improving atrial cuffs. An automatic detection and releasing of the atrial suction effect was also tried. The next problem was acute lung edema accompanied by the postural change of the animal. Development of the automatic control of left atrial pressure could prevent this problem. Small blood leakage from a pinpoint hole in the seal membrane was the next problem. Improvement of the manufacturing procedure of the membrane prevented this. With these improvements, a 10 day survival could be obtained with this unique implantable total artificial heart.
Anticoagulation After Valve Replacement: A Multicenter Retrospective Study
Authors: Kudo Tatsuhiko , Kawase Mitsuhiko , Kawada Shiaki , Kurosawa Hiromi , Koyanagi Hitoshi , Takeuchi Yasuo , Hosoda Yasuyuki , Wanibuchi Yasuhiko
Published: March 2003

Anticoagulant therapy after cardiac valve replacement was evaluated retrospectively in 1,200 patients attending 8 cardiac surgery clinics in the Tokyo area as part of the Tokyo Area Study on Anticoagulation After Cardiac Valve Replacement Using PT‐INR (TAS). A prospective trial is also in progress and will be reported later. The prothrombin time international normalized ratio (PT‐INR) was determined at the time of thromboembolic and bleeding complications in 1,200 patients. During the 5 year study period, thromboembolisms occurred in 21 patients, and bleeding complications occurred in 15 patients. In 71% of patients with thromboembolism and 47% of those with bleeding complications, the PT‐INR was within the range of 1.6 to 2.8, which is the accepted therapeutic range in Japan. Therefore, the correct PT‐INR therapeutic range for Japanese patients with mechanical heart valves needs to be reexamined, and data from the prospective TAS trial that is currently underway will be used for this purpose.
The Merit of Sintered PDLLA/TCP Composites in Management of Bone Fracture Internal Fixation
Authors: Lin Fent‐Huei , Chen Tim‐Mo , Lin Chun‐Pin , Lee Chun‐Jean
Published: March 2003

Polyesters based on lactic acid have been reported in terms of safety and biodegradation in human beings for 2 decades. The greatest advantage of such material is its degradation conducted only by hydrolysis, whereby the ester backbones are supposed to be unchained in the aqueous condition. The final degradable products are carbon dioxide and water which can be metabolized and digested in the physiological environment. The goal of this study was aimed at developing a composite sintered with poly‐DL‐lactide (PDLLA) and tricalcium phosphate (TCP) ceramic particles for orthopedic application. The TCP particles in a range of 30–60 wt% with 5 wt% increments were doped into the PDLLA matrix which was prepared by melting and hot pressing techniques for the reinforcement. The basic mechanical strength, biodegradable behavior, and biological response of the composites were investigated in the study. Various techniques such as pH meter, UV, Fourier‐transform infrared, and x‐ray diffractometer were used to examine and record the degradable process of the composites soaked in saline for 1–16 weeks. The rabbit femur condyle fracture fixation test was used to evaluate tissue compatibility and the effects of bone fracture fixation on the composites. Histological observation and x‐ray photography were used for investigating assistance. The mechanical strength of the composites initially increased with TCP additions up to 50wt%, but thereafter they showed no significant difference (p < 0.05). The composite with 50 wt% TCP addition showed greater mechanical strength and had good agreement with cortical bone in terms of its elastic modulus of 30–40 GPa. The weight loss of the pure PDLLA soaked in the saline started at 4 weeks and reached 95% after 16 weeks. The composites compared with pure PDLLA, however, showed no apparent evidence of degradation after soaked for 12 weeks. The possible mechanisms for the delayed degradation of the composites in saline might have been solution penetration retardation by the ceramic particles and chemical bonds formed between the interface of the TCP particles and the PDLLA matrix. In the histological evaluation of the rabbit femur condyle fracture fixation test, the surface of the composite with 50 wt% TCP addition was attached by the newly generated bone without fibrous tissue around 8 weeks after implantation. The fractured bone was gradually healed and the composite firmly and properly fixed on the fracture area during the implanted period, which provided a breeding environment for normal bone remodeling. The developed composite was thought to be an alternative material for orthopedic application in the future, especially for bone screws and bone plates.
Recombinant Human Erythropoietin Stimulates Production of Interleukin 2 by Whole Blood Cell Cultures of Hemodialysis Patients
Authors: Bryl Ewa , Myśliwska Jolanta , Dębska‐Ślizień Alicja , Trzonkowski Piotr , Rachoń Dominik , Bułło Barbara , Zdrojewski Zbigniew , Myśliwski Andrzej , Rutkowski Bolesław
Published: March 2003

Abstract: The impairment of function of human T lymphocytes, leading to an inappropriate cytokine production, is partially responsible for defective immunological response in hemodialysis patients (HD). Recent data suggest that recombinant human erythropoietin (rhEPO) may exert immunological effects. The aim of this study was to find out whether rhEPO treatment of the HD patients may have an effect on the interleukin 2 (IL‐2) production by their whole blood cell cultures. The study was carried out in 10 HD patients receiving rhEPO for 6 months. Compared with the levels seen before the treatment, the concentration of IL‐2 increased in the phytohemagglutinin‐stimulated whole blood cell cultures of 7 of 10 patients under study. Addition of rhEPO in vitro to the whole blood cell cultures of the HD patients before implementation of erythropoietin confirmed that rhEPO is able to directly stimulate IL‐2 production. Our studies show that the therapy with rhEPO affects IL‐2 secretion.
Tissue Reactions to Polypyrrole‐Coated Polyesters: A Magnetic Resonance Relaxometry Study
Authors: Alikacem Nadir , Marois Yves , Zhang Ze , Jakubiec Barbara , Roy Raynald , King Martin W. , Guidoin Robert
Published: March 2003

Abstract: The electrically conductive properties of polypyrrole (PPy) as a coating on polyester material are very attractive for the manufacture of small diameter blood conduits. However, before these PPy‐coated materials can be investigated for their capacity to generate endothelialized luminal surfaces, they must first be studied for their innocuousness in a living environment. The specific goal of the present study was to investigate the in vivo interactions of PPy‐coated and noncoated woven polyester materials implanted subcutaneously in rats for prescheduled periods of 2, 5, 10, 20, and 30 days. The in vivo magnetic resonance (MR) relaxation times were computed for a small area of muscle tissue adjacent to the implants. A correlation was concurrently attempted with blood monocyte activation studies as well as histological observations of the tissue‐material interface. The progressive pattern of the slower transversal relaxation time (T2s) values revealed a more persistent tissue reaction for the most conductive PPy‐coated materials and a shorter acute tissue response as the surface resistivity increased. Similarly, the blood monocyte activation studies indicated that the thickness of the PPy coating, which correlated with the conductivity, was directly related to tissue response. Furthermore, both the MR and biological studies showed that the PPy‐coated material with a high surface resistivity displayed the lowest tissue reaction over the entire period of implantation. The results obtained from the blood monocyte activation studies and histological observations correlate well with the noninvasive MR measurements of the body's healing process. The conductive materials with high surface resistivities must be further investigated. Finally, the noninvasive nature of MR relaxometry reveals its outstanding potential for future in vivo investigations of the body's tissue interactions with polymers and nonferromagnetic biomaterials.
Interactions Between Platelets and Leukocytes During Hemodialysis
Authors: Bonomini Mario , Sirolli Vittorio , Stuard Stefano , Settefrati Nicola
Published: March 2003

The formation of platelet‐leukocyte microaggregates has been observed in a variety of conditions. When platelets and leukocytes coaggregate, in general, a reciprocal activation occurs when both cells are activated, and the interactions between activated platelets and leukocytes may be relevant in both hemostasis and inflammatory processes. The study of platelet‐leukocyte interactions in hemodialysis offers the novel aspect of cellular‐cellular interaction as a new parameter for evaluating the biocompatibility of dialyzer membranes. This article reviews the investigations of the interactions between platelets and leukocytes during hemodialysis and the pathophysiologic implications which may stem from such interactions.
Development of a New Approach to Vascular Access
Authors: Megerman Joseph , Levin Nathan W. , Ing Todd S. , Dubrow Alan J. , Prosl Frank R.
Published: March 2003

Three modes of access for hemodialysis (HD) have been available for over 20 years, the native arterial to venous (A‐V) fistula, the polytetrafluorethylene (PTFE) graft fistula, and the central venous catheter. Overall, vascular access remains the single most costly source of morbidity and hospitalization in HD patients, indicating a severe need for improvement in this area. A significant contributor to access morbidity is the HD catheter, which protrudes through the skin and is subject to frequent infection. Subcutaneous ports have been developed to overcome this problem with catheters, but their application to HD has been elusive for 2 reasons, the use of a degradable septum that becomes vulnerable to infection with the use of large bore needles and the presence of a nonlinear flow path which produces damage to blood cells and stimulates thrombus formation at the required high flow rates. A new device, the Dialock, overcomes these objections by its use of a mechanical valve that maintains a linear flow path without directly contacting the blood. Results of a pilot study with 23 patients demonstrated a 78% cumulative survival rate after 1 year with a reduced rate of infection compared to catheters and sustained blood flow of 330 ml/min. The device represents a most promising advance in vascular access.
Evaluation of Urea Kinetics Utilizing Stable Isotope Urea and Pharmacokinetic Modeling
Authors: Kaplan Bruce , Wang Zhao , Siddhom Osama , Henthorn Thomas K. , Mujais Salim K.
Published: March 2003

The determination of urea kinetics plays a central role in clinical dialysis prescription. There persist, however, significant limitations to current approaches, particularly as they pertain to rigorous explorations of urea metabolism, distribution, and removal. This report describes methodologies designed to address these limitations by coupling a stable nitrogen isotope method with strict compartmental pharmacokinetic modeling. The findings of the present study can be summarized as follows. First, the use of stable isotope labeled exogenous urea is a reliable clinically applicable method for determination of urea kinetics. Second, this method offers significant advantages in that it allows for an accurate measurement of urea distribution space, endogenous urea production, and nonrenal clearance of urea. Third, this method is significantly more rigorous than urea kinetic models that utilize only endogenous urea and do not carefully fit data points. Finally, pharmacokinetic modeling suggests that a two‐compartment model satisfies all aspects of urea distribution and removal, but these compartments should not be equated with specific physiologic spaces. The combination of stable isotope urea compartmental modeling is a rigorous methodology for the assessment and validation of urea kinetics.
Dialyzer Performance in the Clinic: Comparison of Six Low‐Flux Membranes
Authors: Kerr Peter G. , Lo Angela , Chin Man moo , Atkins Robert C.
Published: March 2003

Abstract: The aim of this study is to assess the clinical performance of 6 different low‐flux dialysis membranes under steady‐state conditions in terms of urea and phosphate clearances. Ten stable hemodialysis patients were examined. The following dialyzers were studied, all in 1.5‐ to 1.6‐m2 format: cuprammonium, cellulose acetate, cellulose diacetate, hemophane, polysulfone (low‐flux), and polysynthane. The following parameters were examined: urea reduction ratio, phosphate reduction ratio, “instantaneous dialyzer clearance” for urea and phosphate, and total amount of urea and phosphate removed in the dialysate over a 1‐week (three dialyses) period. Although there were differences between the membranes, all produced results within a narrow range. There was no one membrane that produced superior clearances in all categories. The cellulose acetate membrane was the least satisfactory membrane. Phosphate clearances were at best one third that of urea clearances. When choosing a low‐flux dialysis membrane, urea and phosphate clearances are so similar amongst different membranes that other criteria are likely to have a greater influence on the choice of membrane.
Significance of Percutaneous Cardiopulmonary Bypass Support for Volume Reduction Surgery with Severe Hypercapnia
Authors: Tsunezuka Yoshio , Sato Hideo , Tsubota Makoto , Seki Masahiro
Published: March 2003

Abstract: In patients with reduced respiratory function, lung resection is associated with high risk because separate ventilation is generally needed for safe management. For patients with end‐stage emphysema, intraoperative respiratory management is important and particularly difficult because neither incomplete oxygenation nor selective ventilation can be performed, so the operation may be interrupted. In this study, we assess the effectiveness of the percutaneous cardiopulmonary support (PCPS) system for lung volume reduction surgery in patients with severe hypercapnia (arterial carbon dioxide tension >50 mm Hg) and discuss the significance of PCPS for patients who are beyond the standard criteria for lung volume reduction surgery (LVRS). We studied 3 patients with severe hypercapnia due to emphysema who underwent volume reduction surgery. One patient was previously treated surgically for contralateral pneumothorax. All patients had a severe smoking history and were suspected to have fragile lungs. During the operation, PCPS provided sufficient support flow. Intraoperative management using PCPS was easy, and no severe complications were observed. One patient exhibited severe hemodynamic deterioration on postoperative Day 15. Other patients' PaCO2 improved postoperatively. One had a calcification of a femoral artery, but there was no trouble inserting a cannula. Bilateral or unilateral volume reduction sugery was performed under PCPS in patients with end‐stage emphysema. We conclude that PCPS is an adjunct to LVRS, useful for intraoperative management of some patients with severe hypercapnea, and the LVRS indications can be extended.
Potentialities and Problems of a Novel Bilateral Ventricular Assist System Without Thoracotomy
Authors: Matsuo Keiichiro , Yano Mitsuhiro , Nakamura Kunihide , Onitsuka Toshio
Published: March 2003

Abstract: Mechanical cardiac assistance can be critical in saving the lives of patients with acute cardiac failure. However, currently used methods of ventricular assistance require advanced technical knowledge and equipment, and only small numbers of patients can be provided with them. Our aim was to develop new cannulas to construct a less invasive biventricular assist system that would permit easy application without thoracotomy. We prepared 2 centrifugal pumps and 4 uniquely shaped cannulas and conducted experiments to investigate the potential and problems of the system. In the first experiment, the system was attached to 6 dogs with ventricular fibrillation to confirm whether our system could maintain cardiac output. In the second experiment, the system was installed for 3 days in 3 goats, and changes in aminotransferases, BUN, creatinine, and plasma free hemoglobin levels were examined. In Experiment 1, it was demonstrated that the system was able to maintain circulation in dogs. In Experiment 2, although the flow rate of the pumps was maintained over 3 days, increased hemolysis and deteriorating renal function were observed. Although these problems need to be solved, the system was still helpful in the management of acute biventricular failure for short periods and may be clinically useful in the near future.
Removal of Immunoglobulins by a Protein A Versus an Antihuman Immunoglobulin G‐Based System: Evaluation of 602 Sessions of Extracorporeal Immunoadsorption
Authors: Matic Goran , Hofmann Doris , Winkler Roland , Tiess Michael , Michelsen Ann , Schneidewind Jana‐Maria , Hebestreit Gabi , Keysser Martin , Müller Waltraud , Kinze Eva‐Maria , Ramlow Wolfgang
Published: March 2003

Abstract: Elimination of IgG can be achieved by extracorporeal immunoadsorption (IA) based on specific binding to either staphylococcal protein A (Excorim) or sheep polyclonal antibodies directed against human IgG (Therasorb). In 602 analyzed sessions of IA, elimination of IgG was 60% through 80% depending on the treated plasma volume, with no significant difference between the mentioned systems. However, the decrease of IgM and IgA was approximately 50% in the anti‐IgG compared to 20–40% in the protein A system. Plasma albumin concentration decreased by 20% in the anti‐IgG system compared to 15% in the protein A system, and hemoglobin values increased by 2% in the anti‐IgG system and decreased by 6% in the protein A system. In conclusion, a clinical relevance for these findings cannot be ruled out, and the individual choice might depend on the clinical situation and laboratory findings.