bluuebunny/crossref_metadata_2025 huggingface dataset:
Thyroid cancer in the renal transplant population: epidemiological study
Authors: Pond Franklin , Serpell Jonathan W. , Webster Angela
Published: March 2005

Background:  The epidemiology of thyroid neoplasms in the renal transplant population has not been widely published. The present study compares the behaviour of thyroid cancer in the transplant cohort with that of the general population. It also documents the transplantation outcomes of patients with thyroid and non‐thyroid cancers.

Methods:  All recipients of renal grafts are registered with the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. Data were obtained from this institution and analysed using Microsoft Excel and stata statistical software. Risk ratio, attributable risk, Mann−Whitney test, and the Kaplan−Meier survival probability were calculated.

Results:  Between 1963 and 31 March 2002, 23 (0.22%) patients were diagnosed with thyroid cancer from a cohort of 10 689 renal transplant recipients. The median age in the renal‐transplant thyroid cancer group was 48.2 years (range: 23−67 years), and there were 11 (48%) male patients, compared to 26% of thyroid cancer patients in the general population (P = 0.02). The median time to thyroid cancer diagnosis after transplantation was 68 months (range: 3−253 months) compared to 102 months (range: 3−363 months; P = 0.004) in non‐thyroid cancers. Ten patients (43%) were found to have lymphatic metastasis, eight of whom presented at the time of primary diagnosis. The risk ratio (RR) was 5.2 (95% confidence interval: 2.0−16.6), with an attributable risk of 17.4 cases per 10 000. There were two cancer‐related deaths resulting in a survival probability of 89% at 5, 10 and 15 years.

Conclusions:  There is a higher incidence of thyroid cancer and an altered sex distribution in the renal transplant population. A significant proportion presents with lymphatic metastasis requiring lymph node dissection and radioactive iodine treatment.
Nerve injuries in orthopaedics: is there anything more we need to tell our patients?
Authors: Ek Eugene T. , Yu Emma P. , Chan Jason T. , Love Bruce R.
Published: March 2005

Background:  Perioperative nerve injuries are uncommon in most elective orthopaedic operations. However, despite the low incidence, patients tend to be most unforgiving when this complication occurs. The present study aims to determine the adequacy of the consent process, and seeks to identify deficiencies.

Methods:  All elective patients who experienced a perioperative nerve palsy between 1996 and 2003 were retrospectively identified. A telephone questionnaire assessed recall of the consent and risks discussed. Patients were asked what they would have liked to have been advised, and whether this would affect their decision for operation.

Results:  Twenty‐four of the 32 patients were contacted. From the questionnaire, 66.7% recalled discussing the risks of the operation. 66.7% would have liked to have discussed, in particular, risk of nerve palsy at time of consent. However, 83.3% of patients, knowing fully the risk of nerve injury, would still have proceeded with the operation. Of the 24 cases, only three had documentation of the risks discussed during consent.

Conclusion:  The need to adequately provide informed consent for nerve dysfunction is present. The present study demonstrates a dilemma between the provision of information and the creation of fear in the minds of recipients of surgery.
Modified saphenous−peritoneal shunt in refractory ascites: new technique
Authors: Chen Jia‐Hui , Liu Hsiao‐Dung , Yu Jyh‐Cherng , Chen Chung‐Jueng , Shih Ming‐Lang , Liu Yao‐Chi , Hsieh Chung‐Bao
Published: March 2005

Background:  Refractory ascites is a serious complication for patients with decompensated liver cirrhosis. Saphenous−peritoneal shunting is a possible surgical treatment for its relief, but tends to lead to higher groin infections. The purpose of the present paper was to determine whether a modified procedure could resolve the problem and offer potential advantages over a peritoneo‐venous shunt.

Methods:  Sixteen patients with refractory ascites who received modified saphenous−peritoneal shunts were studied. Clinical data such as bodyweight, abdominal girth, indocyanine green 15‐min retention rate (ICG‐15), serum bilirubin concentrations, Child−Pugh Score, creatinine clearance (CCr), daily urinary output, urine sodium (UNa) and operative complications were recorded before, and 3 months after, surgery.

Results:  Three months after the operation, the urinary output, nutritional status and Child−Pugh scores had improved, but ICG‐15 and total bilirubin output had not changed significantly. The CCr, UNa bodyweight and abdominal girth tended to decrease, but not significantly. No groin infections were noted following this procedure.

Conclusions:  This modified procedure not only improved the nutritional status of cirrhotic patients with refractory ascites but also improved their quality of life. Infections and obstructions decreased in the short term. However, long‐term follow up is mandatory. This new technique requires more practice and experience.
Enteric and rectal duplications and duplication cysts in the adult
Authors: Simsek Abdurrahman , Zeybek Nazif , Yagci Gokhan , Kaymakcioglu Nihat , Tas Huseyin , Saglam Mutlu , Cetiner Sadettin
Published: March 2005

Alimentary tract duplication and duplication cysts are rare congenital malformations. The ileum is the most frequently affected site. However, alimentary tract duplication and duplication cysts can occur at any point along the gastrointestinal tract. Early diagnosis and prompt surgical treatment is the best way to prevent associated morbidity. This article presents the cases of three patients admitted to Gulhane Military Medical Academy with signs of acute abdomen, intra‐abdominal mass and chronic abdominal pain. These patients were found to have enteric duplication, duplication cyst and/or retro‐rectal cyst. The literature on alimentary tract duplications is reviewed.
Support adapter for radiofrequency ablation probe: experimental study
Authors: Ishikawa Susumu , Oki Shigeru , Muraoka Masato , Kashiwabara Kenji , Morishita Yasuo
Published: March 2005

Background:  The purpose of the present study was to experimentally evaluate a new support adapter, which was created in order to insure a more complete contact between the ablation probe and a beating heart.

Methods:  Support sleeve adapters for the Cobra Cooled probe were fashioned using a semi‐rigid plastic. Forty epicardial radiofrequency ablation (RFA) lesions were created on both atria under the condition of a beating heart in six pigs weighing 26−30 kg. A Cobra Cooled surgical probe was used with continuous internal irrigation of a saline solution (500 mL/h). The ablation temperature was fixed at 80°C and the duration of the RFA in each case was 20, 30 and 60 s.

Results:  A support adapter ensured a more complete epicardial contact between the probe and a beating heart. An RFA probe supported by the adapter delivered greater power to the tissue. The histopathological transmural coagulation was obtained in 82% and 72% in RFA lesions with and without the adaptor, respectively.

Conclusion:  A new adapter was effective in the epicardial RFA under the condition of a beating heart.
Fine‐needle aspiration cytology in parotid masses: our experience in Canterbury, New Zealand
Authors: Riley Neil , Allison Robert , Stevenson Scott
Published: March 2005

Background:  The purpose of the present study was to assess the value of fine‐needle aspiration cytology (FNAC) in parotid masses.

Methods:  A retrospective review was carried out of FNAC results in parotid masses and the findings compared to histology on subsequent parotidectomy.

Results:  One hundred parotid masses were investigated. Eighty‐six had the cytological diagnosis confirmed by histology, 14 had a different diagnosis at histology. In two of these 14, a malignancy was found where a non‐neoplastic condition had been detected. In the other 12, various non‐malignant lesions were wrongly identified by FNAC. Squamous cell carcinoma was the commonest parotid malignancy in the present study.

Conclusion:  Fine‐needle aspiration cytology was found to be an effective diagnostic tool in the hands of experienced pathologists at Christchurch Hospital, NZ.
Single‐breath vital capacity rapid inhalation induction with sevoflurane: feasibility in children
Authors: FERNANDEZ MODESTO , LEJUS CORINNE , RIVAULT OLIVIER , BAZIN VÉRONIQUE , LE ROUX CORINNE , BIZOUARN PHILIPPE , PINAUD MICHEL
Published: March 2005

Background:  Single‐breath vital capacity technique is currently administered for inhalation induction of anesthesia with sevoflurane in adults. Because sevoflurane is used in children, the aim of this open nonrandomized trial was to explore the feasibility and acceptance of this technique in midazolam premedicated patients aged from 4 to 15 years old.

Methods:  A pediatric population (n = 118) was instructed in the vital capacity technique after their arrival in the induction room in a standardized and playful manner. Induction was performed with a circle‐absorber breathing circuit, primed with sevoflurane 7% in 100% O2. Success of the single‐breath vital capacity, delay of induction, hemodynamic and airway tolerance, acceptance by the children and side effects were analyzed. A multivariate logistic regression model was used to identify independent risk factors associated with the failure of the vital capacity technique.

Results:  Single‐breath vital capacity technique was achieved by 57% of the children. The success rate highly correlated with age and ranged from 10% in 4–5 years old to 75% at 11 years and 95% by 14 years. Other factors for success were cooperation and understanding. The need for more than two explanations of the technique was predictive of failure. Delays in the loss of the eyelash reflex and central pupil myosis were obtained in 34 s (18–50) and 242 s (145–278), respectively [median (interquartile ranges)]. Hemodynamic tolerance was good with few airway complications.

Conclusion:  Rapid anesthesia induction using a single‐breath technique with 7% sevoflurane is effective and well tolerated in children, particularly in those above 9 years of age, and in fact, success rate was markedly lower in the young age groups.
Dangerous and severe personality disorder: an ethical concept?
Authors: Glen Sally
Published: March 2005

Abstract  Most clinicians and mental health practitioners are reluctant to work with people with dangerous and severe personality disorders because they believe there is nothing that mental health services can offer. Dangerous and severe personality disorder also signals a diagnosis which is problematic morally. Moral philosophy has not found an adequate way of dealing with personality disorders. This paper explores the question: What makes a person morally responsible for his actions and what is a legitimate mitigating factor? How do psychiatric nurses working with this client group understand the awful things some clients do? What concepts do they need, if they are to know how to explain and how to react? It is suggested that dangerous and severe personality disorder is best regarded as a moral category, framed in terms of goodness, badness, obligation and other ethical concepts. It seems plausible that in important ways the dangerous and severe personality disordered client does not understand morality or understands it differently. The peculiar position of the dangerous and severe personality disordered individual in our system of moral responsibility stems from his apparent inability to see the importance of the interests of others. It might be more helpful to regard personality disordered clients as we do children: partially but not fully reasonable for their actions. We might regard the dangerous and severe personality disordered client responsible for those actions which he most clearly understands, such as causing others physical pain, but not for those with which he is only superficially engaged, such as causing emotional pain. The paper concludes by suggesting that the dangerous and severe personality disordered individual does not fit easily into any conventional moral category, be it criminal, patient, animal or child, and thus an assessment of his moral accountability must take into consideration his special circumstances.
Brain MRI in late‐onset multiple sclerosis
Authors: de Seze J. , Delalande S. , Michelin E. , Gauvrit J. Y. , Mackowiak M. A. , Ferriby D. , Stojkovic T. , Defebvre L. , Pruvo J. P. , Vermersch P.
Published: March 2005

Multiple sclerosis (MS) with clinical onset after 50 years of age is unusual (between 1 and 6%) and is frequently misdiagnosed. Furthermore, brain magnetic resonance imaging (MRI) abnormalities are frequently observed in subjects over 50 years of age. The aim of this study was to describe brain MRI in late‐onset MS to evaluate the sensitivity and specificity of radiological MS criteria in patients aged over 50 years. We evaluated the brain MRI of 20 patients with onset of MS after 50 years of age. We compared these MRI with 26 controls matched for age, sex and vascular risk factors. MRI were blindly analysed by two neuroradiologists according to Paty et al.'s [Neurology38 (1988) 180] criteria, Fazekas et al.'s [Neurology38 (1988) 1822] criteria and Barkhof et al.'s [Brain120 (1997) 2059] criteria. The mean age at MRI scanning was 58 years. Sensitivity was 90% for Paty et al.'s criteria, 80% for Fazekas et al.'s criteria and 85% for Barkhof et al.'s criteria. Specificity was 54% for Paty et al.'s criteria, 69% for Fazekas et al.'s criteria and 65% for Barkhof et al.'s criteria. Barkhof et al.'s criteria are less specific in older patients than in young patients. We suggest that spinal cord MRI and cerebrospinal fluid analysis should be systematically performed in suspected late‐onset MS in order to increase the specificity of the diagnosis.
Cluster Headache and Paroxysmal Hemicrania: Differential Diagnosis
Authors: Zidverc-Trajkovic J , Pavlovic AM , Mijajlovic M , Jovanovic Z , Sternic N , Kostic VS
Published: March 2005

The utility of the differences between cluster headache (CH) and paroxysmal hemicrania (PH) is limited by the considerable overlap of their clinical characteristics. We compared 54 patients with CH and eight patients with PH in terms of demographic features, characteristics of headache attacks, associated autonomic features, temporal forms of disorders, and response to verapamil. According to our results, clinical features that distinguished CH and PH patients were: maximal pain localization, ocular in CH patients and extra-ocular in PH group; mean attack duration was longer and mean attack frequency was lower in CH patients in comparison with PH patients. Conjuctival injection was the only autonomic sign seen more frequently in CH patients. There were more CH patients with episodic and more PH patients with unremitting form of the disorder in examined groups. Although statistical analysis pointed out a significant difference between these clinical features, there was no clinical characteristic that exclusively belonged to one of these headache entities. Demographic characteristics (age, gender, social background), the other headache attack features (nocturnal attacks, interattack tenderness), the other autonomic signs, as well as the response to verapamil did not differ significantly between two groups.
FRAMIG 2000: Medical and Therapeutic Management of Migraine in France
Authors: Lucas C , Chaffaut C , Artaz M-A , Lantéri-Minet M
Published: March 2005

FRAMIG 2000 is a population-based survey of medical and therapeutic management of migraine in France. A total of 312 migraine sufferers were first identified from a representative sample of 4689 adult subjects using a validated questionnaire based on the IHS migraine diagnostic criteria and administered by telephone. Subjects were then interviewed using a branching questionnaire and a computer-assisted interview technique. Although 80% were self-aware of their migrainous state, 82% of migraine sufferers had no medical follow-up for migraine. The proportion of migraine sufferers who did not consult decreased slightly with increasing migraine-related disability (from 87% for subjects in MIDAS grade I to 68% for those in MIDAS grade IV). Migraine sufferers declared to effectively control only four attacks out of 10 after the first intake of the usual treatment. Only 6% of subjects in the survey received a prophylactic treatment for migraine whereas 22% were in MIDAS grade III or IV. These data show that the burden of migraine does not result from a deficit in diagnosis but instead from a deficit in patient information on the proper use of current effective treatments of migraine.
Hepatobiliary transporter expression in human hepatocellular carcinoma
Authors: Zollner Gernot , Wagner Martin , Fickert Peter , Silbert Dagmar , Fuchsbichler Andrea , Zatloukal Kurt , Denk Helmut , Trauner Michael
Published: March 2005

Abstract: Background/Aims: Treatment of hepatocellular carcinoma (HCC) is hampered by resistance to chemotherapy, which might be mediated by multidrug resistance P‐glycoproteins (MDR P‐gps) and MDR‐associated proteins (MRPs). The effectiveness of cytostatics could be further impeded by reduced hepatocellular drug uptake into HCCs. Therefore, we aimed to determine P‐gp, MRP and organic anion transporting protein OATP2 (SLC21A6) expression in HCC. Furthermore, we investigated expression of the major bile salt uptake system Na+/taurocholate cotransporter NTCP (SLC10A1), since bile salt‐coupled chemotherapeutics were proposed to increase therapeutic drug enrichment in HCC.

Material/Methods: mRNA and protein expression and tissue distribution of P‐gps, MRPs, OATP2 and NTCP were assessed in HCC and peritumorous non‐neoplastic tissue by reverse transcription polymerase chain reaction, Western blotting and immunohistochemistry, respectively.

Results: Expression of P‐gps (multidrug export pump MDR1 (ABCB1), phospholipid flippase MDR3 (ABCB4), sister of P‐glycoprotein SPGP (ABCB11)) and basolateral MRP homologue MRP3 (ABCC3) showed a trend for decreased levels in HCC but was highly variable among individual tumors. In contrast, canalicular conjugate export pump MRP2 (ABCC2) expression was generally maintained or even showed a trend towards increased levels. NTCP and OATP2 expression was markedly reduced in most HCCs (P<0.05). Expression of the genuine drug transporter, the concentrative nucleoside transporter (CNT1), was highly variable and showed a trend for reduced levels in HCC.

Summary/Conclusions: MRP2 seems to be the major candidate transporter involved in chemoresistance and reduced expression of OATP2 may further contribute to low drug accumulation in HCCs. Overexpression of drug exporters is not a general feature of HCC but could account for chemoresistance of individual cases. Since expression of uptake systems is generally reduced in HCC, bile salt‐coupled therapeutics may not represent a suitable strategy to overcome insufficient drug enrichment.
Cyclic AMP‐phosphodiesterases inhibitor improves sodium excretion in rats with cirrhosis and ascites
Authors: Ahloulay Mina , Bankir Lise , Lugnier Claire , Le Bec Alain , Poirel Odile , Moreau Richard , Lebrec Didier
Published: March 2005

Background: The mechanisms responsible for renal dysfunction and sodium retention in cirrhosis remain unclear. Cyclic AMP (cAMP) regulates sodium reabsorption in the proximal nephron. This study investigates the role of cAMP metabolism in renal dysfunction in cirrhosis.

Methods: Renal function was studied by the clearance technique in anesthetized control and cirrhotic rats with or without ascites. cAMP phosphodiesterase (PDE) activity was measured in the renal cortex in vitro. Moroever, the effects on renal function of the intravenous administration of cAMP and rolipram, a powerful and specific cAMP‐PDE4 inhibitor, were evaluated.

Results: In control and in non‐ascitic cirrhotic rats, cAMP administration significantly increased sodium and phosphate excretions, but did not change these excretions in cirrhotic rats with ascites. cAMP‐PDE activity was higher in ascitic than in control rats (P<0.05). Rolipram infusion significantly increased sodium and phosphate excretion only in cirrhotic rats with ascites.

Conclusion: These results suggest that increased renal cAMP‐PDE activity is responsible for resistance to the natriuretic effects of cAMP in cirrhosis and plays a role in the development of ascites.
Severity of liver disease does not predict osteopenia or low bone mineral density in primary sclerosing cholangitis
Authors: Campbell Mical S. , Lichtenstein Gary R. , Rhim Andrew D. , Pazianas Michael , Faust Thomas
Published: March 2005

Background: The association between metabolic bone disease and cholestatic liver disease has been poorly characterized. To date a single institution has published data suggesting that in primary sclerosing cholangitis (PSC), advanced liver disease predicts advanced bone disease.

Aim: To determine the association between the severity of liver disease and bone mineral density (BMD) in PSC patients.

Methods: We identified 30 PSC patients who had undergone dual energy X‐ray absorptiometry (DXA) scan. We compared lumbar spine DXA scores between patients with more and less advanced liver disease.

Results: Nine patients were osteopenic (30%), and one patient was osteoporotic. Five patients were female (17%), and none was postmenopausal. BMD was not different between patients listed and not listed for liver transplantation (P=0.49) or between patients with and without hepatic decompensation (P=0.63). Model for end‐stage liver disease (MELD) score (P=0.99) and the modified Mayo risk score (P=0.25) did not predict BMD.

Conclusions: Our study is the first to suggest that low bone density cannot be predicted by the severity of liver disease in PSC. Perhaps other known risk factors for osteoporosis will be important predictors of abnormal bone density in this patient population.
Comparison of recurrence after hepatic resection in patients with hepatitis B vs. hepatitis C‐related small hepatocellular carcinoma in hepatitis B virus endemic area
Authors: Huang Yi‐Hsiang , Wu Jaw‐Ching , Chen Chien‐Hung , Chang Ting‐Tsung , Lee Pui‐Ching , Chau Gar‐Yang , Lui Wing‐Yiu , Chang Full‐Young , Lee Shou‐Dong
Published: March 2005

Abstract: Purpose:Hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are two important factors in the development of hepatocellular carcinoma (HCC). The carcinogenic mechanism of HBV and HCV is considered to be different. It is interesting to compare the recurrence after hepatic resection in patients with small HCC who were infected with HBV or HCV.

Methods:From 1991 to 1995, 145 patients who were positive for hepatitis B surface antigen (HBsAg) or antibody to HCV (anti‐HCV) and diagnosed as small HCC (≤3 cm) in three medical centers in Taiwan were evaluated in this study. All patients underwent hepatic resection. Among them, 83 (57.2%) were infected by HBV, 51 (35.2%) were infected by HCV, and 11 (7.6%) had dual HBV and HCV infection.

Results:Anti‐HCV+ HCCs were associated with older age, lower serum albumin, higher alanine transaminase (ALT) level and multi‐nodular tumors during diagnosis. During the follow‐up, 92 (63.4%) patients developed tumor recurrence. Anti‐HCV+ HCC had a higher cumulated recurrence rate than HBsAg+ HCC (72.4% vs 53.6 % at 5 year,P=0.032). In multivariate analysis, the presence of vascular invasion and lower serum albumin levels (<3.9 g/dl) were the determinants for tumor recurrence.

Conclusions:HCV infection, as compared with HBV infection, had a higher cumulated recurrence after hepatic resection in patients with small HCC. Low serum albumin level was significantly associated with recurrence among these patients.
Interleukin‐6 inhibits cell proliferation in a rat model of hepatocellular carcinoma
Authors: Moran Diarmuid M. , Mayes Nicholas , Koniaris Leonidas G. , Cahill Paul A. , McKillop Iain H.
Published: March 2005

Background: Interleukin‐6 (IL‐6) plays a critical role in normal hepatic growth and liver regeneration. The aims of the present study are to determine the expression of components of IL‐6 signaling in an in vivo model of hepatocellular carcinoma (HCC) and address the role of IL‐6 signaling in the progression of HCC.

Methods: An in vivo rat HCC model was established and IL‐6 receptor (IL‐6R) and downstream signaling pathway expression and activity were determined in HCC and normal liver specimens. Tumorigenic HCC cells from resected HCC samples and normal hepatocytes were then isolated and cultured in the presence and absence of recombinant human IL‐6 (rhIL‐6).

Results: HCC specimens demonstrated decreased IL‐6Rα/gp130 expression as compared with the normal liver. In contrast, HCC samples had significantly increased IL‐6 messenger RNA expression and signal transducers and activators of transcription (STAT)3 activity. Using in vitro cell cultures, we demonstrated that IL‐6 stimulated STAT3 and extracellular regulated kinase (ERK) activity in both HCC cells and isolated hepatocytes. However, while STAT3 activation profiles were similar, IL‐6 stimulated ERK activity in a biphasic manner in HCC cells and a monophasic, sustained ERK activation in hepatocytes. In HCC cells, a significant induction of cyclin‐dependent kinase (CDK) inhibitors, p21waf1/cip1 and p27Kip1 occurred, an effect that was not observed in normal hepatocytes. Finally, we established that IL‐6 acted to inhibit serum‐stimulated DNA synthesis and cell mitogenesis in HCC cells in vitro.

Conclusions: These data demonstrate altered expression of components of IL‐6 signaling in HCC in vivo. IL‐6 treatment of HCC cells inhibits serum‐stimulated mitogenesis, possibly via differences in activation profiles of intracellular signaling pathways and their effect on CDK inhibitor expression/activity.
Transjugular intrahepatic portosystemic shunt in refractory ascites: a meta‐analysis
Authors: Deltenre P. , Mathurin P. , Dharancy S. , Moreau R. , Bulois P. , Henrion J. , Pruvot F. R. , Ernst O. , Paris J. C. , Lebrec D.
Published: March 2005

Abstract: Transjugular intrahepatic portosystemic shunt (TIPS) is a more effective treatment for refractory ascites than large volume paracentesis (LVP), but the magnitude of its effect in terms of control of ascites, encephalopathy and survival has not been established.

Aim: This meta‐analysis compare TIPS to LVP in terms of control of ascites at 4 and 12 months, encephalopathy and survival at 1 and 2 years.

Results: Five randomized controlled trials involving 330 patients were included. In the TIPS group, control of ascites was more frequently achieved at 4 months (66% vs 23.8%, mean difference: 41.4%, 95% confidence interval (CI): 29.5–53.2%, P<0.001) and 12 months (54.8% vs 18.9%, mean difference: 35%, 95% CI: 24.9–45.1%, P<0.001), whereas encephalopathy was higher (54.9% vs 38.1%, mean difference: 17%, 95% CI: 7.3–26.6%, P<0.001). Survival at 1 year (61.7% vs 56.5%, mean difference: 3.2%, 95% CI: −14.7 to 21.9%) and 2 years (50% vs 42.8%, mean difference: 6.8%, 95% CI: −10 to 23.6%) were not significantly different.

Conclusions: TIPS is a more effective treatment for refractory ascites than LVP. However, TIPS increase encephalopathy and does not improve survival.
Correlation between microtomography and histomorphometry for assessment of implant osseointegration
Authors: Park Young‐Seok , Yi Ki‐Young , Lee In‐Seop , Jung Young‐Chul
Published: March 2005

Abstract: Microtomographic techniques are widely used for studying the trabecular architectures in the orthopedics and elucidation of tooth micromorphology in the field of dentistry. Its application to assess the osseointegration of dental implants has been studied as a non‐invasive method, contrary to several conventional methods. The aim of this study is to evaluate the possibility of microtomography as a tool for assessing osseointegration. Twenty‐four titanium dental implants (3.75 mm in diameter and 7 mm in total length) were installed in the tibia of New Zealand white rabbits, and retrieved with the surrounding bone after 3 months. The specimens were analyzed by three‐dimensional microtomogram images (Skyscan 1074) and compared with the conventional histomorphography. The correlation coefficient was found to be 0.855, which means the two data sources are significantly correlated statistically. To predict the histomorphometric data using microtomographic data, a linear regression model was applied. These results showed some promise of using microtomograms for non‐invasive osseointegration assessment if the methods can be calibrated more precisely by further study.
Laser therapy accelerates initial attachment and subsequent behaviour of human oral fibroblasts cultured on titanium implant material
Authors: Khadra Maawan , Kasem Nesrin , Lyngstadaas Ståle Petter , Haanæs Hans R. , Mustafa Kamal
Published: March 2005

Abstract: The aim of the study was to investigate the effect of low‐level laser therapy (LLLT) on attachment and proliferation of human gingival fibroblasts (HGF) cultured on titanium implant material. HGF were exposed to gallium–aluminum–arsenide diode laser at dosages of 1.5 or 3 J/cm2 and then cultured on commercially pure titanium discs. Cell profile areas were measured after 1, 3 and 24 h, using scanning electron microscopy and an automatic image analyzer. The results were expressed as percentage of attachment. In order to investigate the effect of LLLT on cellular growth after 8 and 10 days, HGF were cultured on titanium discs for 24 h and then exposed to laser irradiation on 3 consecutive days. Colony‐forming efficiency (CFE) and clonal growth rates (CGR) were measured. Cell viability was determined by Hoechst and prodidium iodide staining. Non‐lased cultures served as controls. Morphologically, the cells spread well on all titanium surfaces, indicating good attachment by both irradiated and non‐irradiated cells. Fibroblasts exposed to laser irradiation had significantly higher percentages of cell attachment than the non‐exposed cells (P<0.05). CFE and CGR were also enhanced for the irradiated cells (P<0.05). Cell viability was high (>90%) in the irradiated and control groups, without significant differences. It is concluded that in vitro LLLT enhances the attachment and proliferation of HGF on titanium implant material.
Bone morphology and vascularization of untreated and guided bone augmentation‐treated rabbit calvaria: evaluation of an augmentation model
Authors: Slotte Christer , Lundgren Dan , Sennerby Lars
Published: March 2005

Objectives: Cranial vault is widely used in experimental models on membranous bone healing in general, guided bone augmentation (GBA) studies being one example. To our knowledge, however, few studies on the characteristics of the untreated calvaria regarding bone density, vessel topography, and their intra/interindividual variations and associations are available. The aims of this investigation were to (1) map the large vessel topography of the skull vault, (2) describe the parietal bones of the adult rabbit histologically and morphometrically, and (3) histologically compare untreated parietal bone with parietal bone that had been treated with a GBA device.

Material and methods: Ten adult untreated rabbits were microangiographed. General anesthesia was induced and the mediastinum was opened. Heparin and lidocaine were injected in the aorta followed by perfusion with India ink. After death, en bloc biopsies of the skull vault including the overlying soft tissues and dura mater were taken. The specimens were cleared with the Spalteholtz technique, microscopically examined, and digitally imaged. Thereafter, circular biopsies were harvested to obtain decalcified sections. In addition, sections from 14 GBA‐treated rabbit skulls (of the same race, sex and age as the untreated animals) served as reference specimens for comparison. Histomorphometric examinations were carried out.

Results: In the cleared specimens, all parietal bones were found to be supplied by one major branch of the meningeal artery. From each of these, separate branches supplied the dura wherein a fine vessel network covered the bone. No major vessels were found in the supracalvarial soft tissue. Numerous fine vessels were found within the periosteum and dura entering the cortical plates. The decalcified sections of the parietal bones revealed an outer and inner cortical plate enveloping a diploic space containing bone trabeculae, marrow tissue and larger sinusoids. Hollow connections were frequently found in both the outer and inner cortical plates in both the untreated and the GBA‐treated specimens. These connections contained marrow tissue that extended to the periosteum and the dura. The morphometric measurements revealed similar proportions of cortical, trabecular, and marrow areas in the right and left untreated bones. The area of the outer cortical plate was significantly larger than the area of the inner cortical plate. Bone density was similar in the right and left untreated and GBA‐treated specimens, as was the frequency and width of hollow connections through the cortical bone plates.

Conclusions: The symmetry between the left and right parietal bones concerning the large vessel topography and the histomorphometric parameters assessed was high. Hollow connections in the cortical plates were frequently found. The bilateral use of the parietal bones is suggested to be reliable in experimental GBA models regarding the blood supply and bone quality.
Linkage mapping of four chicken calpain genes
Authors: OKUMURA Fumihiko , SHIMOGIRI Takeshi , SHINBO Yoko , YOSHIZAWA Kanako , KAWABE Kotaro , MANNEN Hideyuki , OKAMOTO Shin , CHENG Hans H. , MAEDA Yoshizane
Published: March 2005

Calpains are intracellular Ca2+‐dependent proteases and enzymes that contribute to growth and meat quality. In the present study, we identified polymorphisms in four calpain genes (CAPN1, CAPN2, CAPN3, and CAPN1.5) expressed ubiquitously in chicken using polymerase chain reaction‐restriction fragment length polymorphism, and mapped them using two backcross families (East Lansing (EL) and Kobe University (KU)). CAPN2 and CAPN1.5 mapped to two locations on chromosome 3 about 30 cM apart, while CAPN3 mapped to chromosome 5. CAPN1 was linked to a previously unlinked microsatellite marker LEI0140 to form a new linkage group called E66. CAPN2 and CAPN3 extend the amount of conserved synteny between chicken chromosome 3 and human chromosome 1, and between chicken chromosome 5 and human chromosome 15, respectively. Although CAPN2, CAPN3, and CAPN1.5 were found in the University of California Santa Cruz chicken genome browser gateway, CAPN1 and LEI0140 were not in specific genomic positions.
Allele frequencies of the extension locus encoding the melanocortin‐1 receptor in Japanese and Korean cattle
Authors: SASAZAKI Shinji , USUI Munehiro , MANNEN Hideyuki , HIURA Chihiro , TSUJI Soichi
Published: March 2005

In order to estimate the influence of the Extension (E) locus in cattle coat color, the melanocortin‐1 receptor (MC1R) gene in Japanese Black, Japanese Brown and Korean (Hanwoo) cattle were sequenced. The sequences of the coding region revealed three alleles (ED, E+ and e), which were previously reported. Polymerase chain reaction‐restriction fragment length polymorphism was performed to investigate the gene frequencies of the three breeds. Japanese Black was almost composed of ED and E+ individuals, ED = 0.481 and E+ = 0.514, and no homozygous e/e, therefore that is consistent with the hypothesis that ED and E+ induce black pigment synthesis. Allele frequencies between Japanese Brown and Hanwoo were obviously different; however, recessive red e allele frequency was 0.038 for Japanese Brown and 0.948 for Hanwoo, even though both breeds have quite similar coat colors (ranging from yellowish brown to dark brown including a red coat color). This result suggested that other genes are also associated with a coat color of red and brown in cattle.
Regulation of Major Cellulosomal Endoglucanases of
Clostridium thermocellum
Differs from That of a Prominent Cellulosomal Xylanase
Authors: Dror Tali W. , Rolider Adi , Bayer Edward A. , Lamed Raphael , Shoham Yuval
Published: March 2005

The expression of scaffoldin-anchoring genes and one of the major processive endoglucanases (CelS) from the cellulosome of
Clostridium thermocellum
has been shown to be dependent on the growth rate. For the present work, we studied the gene regulation of selected cellulosomal endoglucanases and a major xylanase in order to examine the previously observed substrate-linked alterations in cellulosome composition. For this purpose, the transcript levels of genes encoding endoglucanases CelB, CelG, and CelD and the family 10 xylanase XynC were determined in batch cultures, grown on either cellobiose or cellulose, and in carbon-limited continuous cultures at different dilution rates. Under all conditions tested, the transcript levels of
celB
and
celG
were at least 10-fold higher than that of
celD
. Like the major processive endoglucanase CelS, the transcript levels of these endoglucanase genes were also dependent on the growth rate. Thus, at a rate of 0.04 h
−1
, the levels of
celB
,
celG
, and
celD
were threefold higher than those obtained in cultures grown at maximal rates (0.35 h
−1
) on cellobiose. In contrast, no clear correlation was observed between the transcript level of
xynC
and the growth rate—the levels remained relatively high, fluctuating between 30 and 50 transcripts per cell. The results suggest that the regulation of
C. thermocellum
endoglucanases is similar to that of the processive endoglucanase
celS
but differs from that of a major cellulosomal xylanase in that expression of the latter enzyme is independent of the growth rate.
SarA Is an Essential Positive Regulator of
Staphylococcus epidermidis
Biofilm Development
Authors: Tormo María Ángeles , Martí Miguel , Valle Jaione , Manna Adhar C. , Cheung Ambrose L. , Lasa Iñigo , Penadés José R.
Published: March 2005

Staphylococcus epidermidis
biofilm formation is associated with the production of the polysaccharide intercellular adhesin (PIA)--poly-
N
-acetylglucosamine polysaccharide (PNAG) by the products of the
icaADBC
operon. Recent evidence indicates that SarA, a central regulatory element that controls the production of
Staphylococcus aureus
virulence factors, is essential for the synthesis of PIA/PNAG and the ensuing biofilm development in this species. Based on the presence of a
sarA
homolog, we hypothesized that SarA could also be involved in the regulation of the biofilm formation process in
S. epidermidis
. To investigate this, we constructed nonpolar
sarA
deletions in two genetically unrelated
S. epidermidis
clinical strains, O-47 and CH845. The SarA mutants were completely defective in biofilm formation, both in the steady-state conditions of a microtiter dish assay and in the flow conditions of microfermentors. Reverse transcription-PCR experiments showed that the mutation in the
sarA
gene resulted in downregulation of the
icaADBC
operon transcription in an IcaR-independent manner. Purified SarA protein showed high-affinity binding to the
icaA
promoter region by electrophoretic mobility shift assays. Consequently, mutation in
sarA
provoked a significant decrease in the amount of PIA/PNAG on the cell surface. Furthermore, heterologous complementation of
S. aureus sarA
mutants with the
sarA
gene of
S. epidermidis
completely restored biofilm formation. In summary, SarA appeared to be a positive regulator of transcription of the
ica
locus, and in its absence, PIA/PNAG production and biofilm formation were diminished. Additionally, we present experimental evidence showing that SarA may be an important regulatory element that controls
S. epidermidis
virulence factors other than biofilm formation.
Insights on Evolution of Virulence and Resistance from the Complete Genome Analysis of an Early Methicillin-Resistant
Staphylococcus aureus
Strain and a Biofilm-Producing Methicillin-Resistant
Staphylococcus epidermidis
Strain
Authors: Gill Steven R. , Fouts Derrick E. , Archer Gordon L. , Mongodin Emmanuel F. , DeBoy Robert T. , Ravel Jacques , Paulsen Ian T. , Kolonay James F. , Brinkac Lauren , Beanan Mauren , Dodson Robert J. , Daugherty Sean C. , Madupu Ramana , Angiuoli Samuel V. , Durkin A. Scott , Haft Daniel H. , Vamathevan Jessica , Khouri Hoda , Utterback Terry , Lee Chris , Dimitrov George , Jiang Lingxia , Qin Haiying , Weidman Jan , Tran Kevin , Kang Kathy , Hance Ioana R. , Nelson Karen E. , Fraser Claire M.
Published: March 2005

Staphylococcus aureus
is an opportunistic pathogen and the major causative agent of numerous hospital- and community-acquired infections.
Staphylococcus epidermidis
has emerged as a causative agent of infections often associated with implanted medical devices. We have sequenced the ∼2.8-Mb genome of
S. aureus
COL, an early methicillin-resistant isolate, and the ∼2.6-Mb genome of
S. epidermidis
RP62a, a methicillin-resistant biofilm isolate. Comparative analysis of these and other staphylococcal genomes was used to explore the evolution of virulence and resistance between these two species. The
S. aureus
and
S. epidermidis
genomes are syntenic throughout their lengths and share a core set of 1,681 open reading frames. Genome islands in nonsyntenic regions are the primary source of variations in pathogenicity and resistance. Gene transfer between staphylococci and low-GC-content gram-positive bacteria appears to have shaped their virulence and resistance profiles. Integrated plasmids in
S. epidermidis
carry genes encoding resistance to cadmium and species-specific LPXTG surface proteins. A novel genome island encodes multiple phenol-soluble modulins, a potential
S. epidermidis
virulence factor.
S. epidermidis
contains the
cap
operon, encoding the polyglutamate capsule, a major virulence factor in
Bacillus anthracis
. Additional phenotypic differences are likely the result of single nucleotide polymorphisms, which are most numerous in cell envelope proteins. Overall differences in pathogenicity can be attributed to genome islands in
S. aureus
which encode enterotoxins, exotoxins, leukocidins, and leukotoxins not found in
S. epidermidis
.
The
relA
Homolog of
Mycobacterium smegmatis
Affects Cell Appearance, Viability, and Gene Expression
Authors: Dahl John L. , Arora Kriti , Boshoff Helena I. , Whiteford Danelle C. , Pacheco Sophia A. , Walsh Olaus J. , Lau-Bonilla Dalia , Davis William B. , Garza Anthony G.
Published: March 2005

The modification of metabolic pathways to allow for a dormant lifestyle appears to be an important feature for the survival of pathogenic bacteria within their host. One regulatory mechanism for persistent
Mycobacterium tuberculosis
infections is the stringent response. In this study, we analyze the stringent response of a nonpathogenic, saprophytic mycobacterial species,
Mycobacterium smegmatis
. The use of
M. smegmatis
as a tool for studying the mycobacterial stringent response was demonstrated by measuring the expression of two
M. tuberculosis
genes,
hspX
and
eis
, in
M. smegmatis
in the presence and absence of

rel
Msm

. The stringent response plays a role in
M. smegmatis
cellular and colony formation that is suggestive of changes in the bacterial cell wall structure.
Crystal Structure of the Terminal Oxygenase Component of Cumene Dioxygenase fromPseudomonas fluorescensIP01
Authors: Dong Xuesong , Fushinobu Shinya , Fukuda Eriko , Terada Tohru , Nakamura Shugo , Shimizu Kentaro , Nojiri Hideaki , Omori Toshio , Shoun Hirofumi , Wakagi Takayoshi
Published: March 2005

The crystal structure of the terminal component of the cumene dioxygenase multicomponent enzyme system ofPseudomonas fluorescensIP01 (CumDO) was determined at a resolution of 2.2 Å by means of molecular replacement by using the crystal structure of the terminal oxygenase component of naphthalene dioxygenase fromPseudomonassp. strain NCIB 9816-4 (NphDO). The ligation of the two catalytic centers of CumDO (i.e., the nonheme iron and Rieske [2Fe-2S] centers) and the bridging between them in neighboring catalytic subunits by hydrogen bonds through a single amino acid residue, Asp231, are similar to those of NphDO. An unidentified external ligand, possibly dioxygen, was bound at the active site nonheme iron. The entrance to the active site of CumDO is different from the entrance to the active site of NphDO, as the two loops forming the lid exhibit great deviation. On the basis of the complex structure of NphDO, a biphenyl substrate was modeled in the substrate-binding pocket of CumDO. The residues surrounding the modeled biphenyl molecule include residues that have already been shown to be important for its substrate specificity by a number of engineering studies of biphenyl dioxygenases.
Transcriptome Analysis ofShewanella oneidensisMR-1 in Response to Elevated Salt Conditions
Authors: Liu Yongqing , Gao Weimin , Wang Yue , Wu Liyou , Liu Xueduan , Yan Tinfeng , Alm Eric , Arkin Adam , Thompson Dorothea K. , Fields Matthew W. , Zhou Jizhong
Published: March 2005

Whole-genomic expression patterns were examined inShewanella oneidensiscells exposed to elevated sodium chloride. Genes involved in Na+extrusion and glutamate biosynthesis were significantly up-regulated, and the majority of chemotaxis/motility-related genes were significantly down-regulated. The data also suggested an important role for metabolic adjustment in salt stress adaptation inS. oneidensis.
CURRENT AND FUTURE TRENDS IN FEATURE SELECTION AND EXTRACTION FOR CLASSIFICATION PROBLEMS
Authors: HOLDER LAWRENCE B. , RUSSELL INGRID , MARKOV ZDRAVKO , PIPE ANTHONY G. , CARSE BRIAN
Published: March 2005

In this article, we describe some of the important currently used methods for solving classification problems, focusing on feature selection and extraction as parts of the overall classification task. We then go on to discuss likely future directions for research in this area, in the context of the other articles from this special issue. We propose that the next major step is the elaboration of a theory of how the methods of selection and extraction interact during the classification process for particular problem domains, along with any learning that may be part of the algorithms. Preferably this theory should be tested on a set of well-established benchmark challenge problems. Using this theory, we will be better able to identify the specific combinations that will achieve best classification performance for new tasks.
STRANGE ATTRACTORS IN PERIODICALLY KICKED CHUA'S CIRCUIT
Authors: WANG QIUDONG , OKSASOGLU ALI
Published: March 2005

In this paper, we discuss a new mechanism for chaos in light of some new developments in the theory of dynamical systems. It was shown in [Wang & Young, 2002b] that strange attractors occur when an autonomous system undergoing a generic Hopf bifurcation is subjected to a weak external forcing that is periodically turned on and off. For illustration purposes, we apply these results to the Chua's system. Derivation of conditions for chaos along with the results of numerical simulations are presented.
NEW TYPE OF DATA TRANSMISSION USING A SYNCHRONIZATION OF CHAOTIC SYSTEMS
Authors: DJEMAÏ M. , BARBOT J.-P. , BOUTAT D.
Published: March 2005

In this article, the secure transmission of data is being realized on the basis of the synchronization of two chaotic systems. The transmitted signal is only the sign of a projection of the state. This has the advantage of making the transmission not very sensitive to the noises of transmission and the attenuation of the transmitted signal without using a VCO (Voltage Control Oscillatory) into the transmitter and the receiver. It should be noted that for the considered type of chaotic system, the traditional conditions of observability and linearization by injection of outputs are not checked. Here, we can only carry out an estimator.