bluuebunny/crossref_metadata_2025 huggingface dataset:
An Adaptive Source-Channel Coding with Feedback for Progressive Transmission of Medical Images
Authors: Lo Jen-Lung , Sanei Saeid , Nazarpour Kianoush
Published: January 2009

A novel adaptive source-channel coding with feedback for progressive transmission of medical images is proposed here. In the source coding part, the transmission starts from the region of interest (RoI). The parity length in the channel code varies with respect to both the proximity of the image subblock to the RoI and the channel noise, which is iteratively estimated in the receiver. The overall transmitted data can be controlled by the user (clinician). In the case of medical data transmission, it is vital to keep the distortion level under control as in most of the cases certain clinically important regions have to be transmitted without any visible error. The proposed system significantly reduces the transmission time and error. Moreover, the system is very user friendly since the selection of the RoI, its size, overall code rate, and a number of test features such as noise level can be set by the users in both ends. A MATLAB-based TCP/IP connection has been established to demonstrate the proposed interactive and adaptive progressive transmission system. The proposed system is simulated for both binary symmetric channel (BSC) and Rayleigh channel. The experimental results verify the effectiveness of the design.
How Do Changes in Water Quality and Dialysate Composition Affect Clinical Outcomes?
Authors: Hoenich Nicholas A. , Levin Robert , Ronco Claudio
Published: January 2009

Dialysis relies upon the transfer of waste products and electrolytes across a semi-permeable membrane contained in the dialyser facilitated by the dialysis fluid, a fast-flowing electrolyte solution prepared continuously by the mixing of treated water with a concentrated electrolyte solution. Both the water, the buffer and electrolyte composition play important roles in modulating complications associated with treatment. With respect to water, historically the focus was on chemical contaminant content, but more recently has shifted to microbiological quality due to the role that such quality plays in the pro-inflammatory state. The composition of the dialysis fluid is crucial in normalization of electrolyte composition of plasma water, homeostasis and acid-base balance, and should be individualized to the patients’ requirements in the same way as blood and dialysate flow rates are individualized to ensure optimal comfort and minimal complications associated with the procedure.
The Medical Directorship of Renal Dialysis Facilities under the New Medicare Conditions for Coverage: Challenges and Opportunities
Authors: DeOreo Peter B.
Published: January 2009

The new Medicare conditions for coverage for providers of end-stage renal disease services provide both a challenge and an opportunity for medical directors. The conditions expect active clinical leadership in quality improvement and the performance of the facility staff and medical staff. These new rules define patient assessment and care planning processes that complement the quality assessment and performance improvement (QAPI) program. Infection control, patient safety and error reduction are given new emphasis. The interdisciplinary team (IDT) under the leadership of the medical director will advance the quality and safety of the patients under their care. Patients’ rights and autonomy are stressed. The QAPI/IDT will monitor complaints, satisfaction surveys, and grievances to minimize involuntary discharge. The medical director will report the results of the QAPI program to the governing body. Medical directors will find that participation in renal network quality improvement programs and initiatives will enhance their facility’s QAPI program.
Vascular Access: The Past, Present and Future
Authors: Sands Jeffrey J.
Published: January 2009

Over the past 40 years, improvements in vascular access management have enhanced patient outcomes and decreased an epidemic of access failure. Arteriovenous fistulae are again the access of choice and new percutaneous therapies and outpatient access centers have revolutionized the therapeutic approach to access failure. Evidence-based guidelines, supported by national and international outcome data have helped rationalize vascular access care. Current challenges and, in particular, the increased use of catheters with resultant increases in patient morbidity and mortality must be rapidly addressed to protect patients and decrease the unacceptably high rates of catheter-related infection. Future technologies will continue to improve vascular access management. Our ability to utilize these new approaches to benefit patients will depend on appropriate application, continued development of standardized delivery systems utilizing outcome measures and payment systems that support and incent outcome improvement.
Role of Vasopressin and Vasopressin Receptor Antagonists in Type I Cardiorenal Syndrome
Authors: Schrier Robert W. , Masoumi Amirali , Elhassan Elwaleed
Published: January 2009

The pathogenesis of cardiac failure involves activation of the neurohumoral axis including stimulation of the sympathetic nervous system, the renin-angiotensin-aldosterone, and nonosmotic vasopressin systems. While these responses are critical in maintaining arterial pressure, they are associated with renal vasoconstriction, as well as sodium and water retention. In advanced circumstances, renal dysfunction and hyponatremia occur with cardiac failure. Even a modest rise in serum creatinine related to diminished renal function in heart failure patients is associated with increased risk for cardiovascular morbidity and mortality. Similarly, increased thirst and the nonosmotic stimulation of vasopressin in advanced cardiac failure leads to hyponatremia, which is also a major risk factor for mortality. Currently, V2 vasopressin receptor antagonists have been shown to correct hyponatremia in cardiac failure. One such agent, conivaptan, also is a V1 receptor antagonist which could theoretically benefit heart failure patients by decreasing cardiac afterload and remodeling. The effect of V2 receptor antagonists to correct hyponatremia in heart failure patients appears to be quite safe. However, to date no effect on mortality has been demonstrated.
Validity of Internal Filtration-Enhanced Hemodialysis as a New Hemodiafiltration Therapy
Authors: Mineshima Michio , Ishimori Isamu , Sakiyama Ryoichi
Published: January 2009

In order to improve solute removal efficiency, several types of dialyzers with enhanced internal filtration (IF) were introduced for clinical applications. In these dialyzers, enhanced IF increased convective transport of the solute in addition to diffusive transport. Internal filtration-enhanced hemodialysis (IFEHD) defined as hemodialysis therapy using the enhanced IF dialyzer seems to be more convenient in comparison with conventional hemodiafiltration therapies because of no additional equipments such as a roller pump. In this paper, the validity of IFEHD was examined during several types of experimental studies. As a result, the experimental study with several types of enhanced IF dialyzers indicated values of relative solute clearance in an aqueous solution that were higher than unity compared to the conventional dialyzer. The K values obtained for myoglobin as a larger molecule were more than twice as high. The value of IF flow rate (QIF) was evaluated by pulsed Doppler ultrasonography. The blood flow velocity at a cross-sectional plane of the dialyzer was directly measured along the dialyzer during a bovine in vitro study using a newly developed probe slider. Doppler ultrasonography is a useful method as a bedside monitoring of the QIF value in a dialyzer because it is noninvasive for the patient. Time course of the QIF value was examined for 6 h during a bovine in vitro study. The QIF decreased within 45 min after the start of the experiment and reached constant values after that. Although creatinine and β2-microglobulin K values remained constant with time during the experiment, α1-microglobulin K values gradually and albumin K value steeply decreased with time. This is because these solutes transfer through the membrane strongly affected by fouling. The validity of IFEHD was clarified during the experimental studies. Development of a dialyzer with enhanced IF, however, should take account of the patient’s safety. Contaminations such as endotoxin invasion from the dialysate to the patient should be avoided.
Reduction of Hepatitis C Virus Using Lectin Affinity Plasmapheresis in Dialysis Patients
Authors: Tullis Richard H. , Duffin R. Paul , Handley Harold H. , Sodhi Puneet , Menon Jeevan , Joyce James A. , Kher Vijay
Published: January 2009

Background/Aims: To test the safety and efficacy of the Aethlon Hemopurifier®, a lectin affinity cartridge, in clearing hepatitis C virus (HCV) from the blood of HCV-positive end-stage renal disease patients undergoing dialysis. Viral RNA was measured using real-time quantitative reverse transcriptase polymerase chain reaction. Results: HCV clearance from plasma or blood was measured using either direct capture on immobilized Galanthus nivalis agglutinin (GNA) or using miniature plasmapheresis cartridges containing immobilized GNA. HCV in plasma samples was rapidly cleared by direct affinity capture (t1/2 = approx. 20 min) and HCV in human blood was cleared using the Hemopurifier (t1/2 = 2–3 h). Institutional-review-board-sanctioned clinical safety studies were conducted at the Apollo and Fortis Hospitals in India. At Apollo, 4 patients were treated 3 times/week for 2 weeks. HCV captured on the Hemopurifier averaged 8.9 × 108 viral copies/cartridge (n = 5), representing approximately 30% of the initial viral body burden. At Fortis, 3 patients treated 3 times/week for 1 week completed the viral load studies. Two patients showed measurable viral load reduction, while the third showed both increases and decreases in viral load. After Hemopurifier treatment, average HCV viral load was reduced by 57%. Surprisingly, average viral load was also 82% lower 7 days after treatment. Control samples also showed a marked transient reduction in HCV viral load as previously reported. Conclusion: The Hemopurifier rapidly cleared HCV from blood treated in vitro. In patients, the combination of the Hemopurifier plus dialysis decreased HCV viral load by 57% in 1 week. Moreover, viral load reduction continued up to 7 days after treatment.
Bioimpedance Analysis in Dialysis: State of the Art and What We Can Expect
Authors: Tattersall James
Published: January 2009

Dialysis must control the body’s fluid content accurately in order to maintain optimal health. The only commonly used, practical and objective measurements we have to guide fluid removal are very inaccurate. Recent study has validated bioimpedance (BIA) as an objective measure of fluid and nutritional status in dialysis patients. There are a number of different methods suitable for routine use available to the clinician. Single-frequency whole-body BIA uses inexpensive equipment capable of almost instantaneous or continuous measurement. The results can be used to give an indication of a patient’s fluid content, nutrition and body composition when compared to appropriate reference values. Multiple-frequency whole-body BIA can be used to calculate excess fluid volume to within 1–2 liters. The equipment is more expensive than for single-frequency BIA, but the output is much easier to interpret. Multiple-frequency segmental BIA is more complicated to perform, but subject to less interference from changes in fluid distribution (e.g. resulting from hemodialysis or changes in posture). It is not suitable for routine use but could be considered as a gold standard for occasional clinical BIA.
Importance of Whole-Body Bioimpedance Spectroscopy for the Management of Fluid Balance
Authors: Wabel Peter , Chamney Paul , Moissl Ulrich , Jirka Tomas
Published: January 2009

Introduction: Achieving normohydration remains a non-trivial issue in haemodialysis therapy. Preventing the deleterious effects of fluid overload and dehydration is difficult to achieve. Objective and clinically applicable methods for the determination of a target representing normohydration are needed. Methods: Whole-body bioimpedance spectroscopy (50 frequencies, 5–1,000 kHz) in combination with a physiologic tissue model can provide an objective target for normohydration based on the concept of excess extracellular volume. We review the efficacy of this approach in a number of recent clinical applications. The accuracy to determine fluid volumes (e.g. extracellular water), body composition (e.g. fat mass) and fluid overload was evaluated in more than 1,000 healthy individuals and patients against available gold standard reference methods (e.g. bromide, deuterium, dual-energy X-ray absorptiometry, air displacement plethysmography, clinical assessment). Results: The comparison with gold standard methods showed excellent accordance [e.g. R2 (total body water) = 0.88; median ± SD (total body water) = –0.17 ± 2.7 litres]. Agreement with high-quality clinical assessment of fluid status was demonstrated in several hundred patients (median ± SD = –0.23 ± 1.5 litres). The association between ultrafiltration volume and change in fluid overload was reflected well by the method (median ± SD = 0.015 ± 0.8 litres). The predictive value of fluid overload on mortality underlines forcefully the clinical relevance of the normohydration target, being secondary only to the presence of diabetes. The objective normohydration target could be achieved in prevalent haemodialysis patients leading to an improvement in hypertension and reduction of adverse events. Conclusion: Whole-body bioimpedance spectroscopy in combination with a physiologic tissue model provides for the first time an objective and relevant target for clinical dry weight assessment.
Bacterial DNA in Water and Dialysate: Detection and Significance for Patient Outcomes
Authors: Handelman Garry J. , Megdal Peter A. , Handelman Samuel K.
Published: January 2009

The fluid used for hemodialysis may contain DNA fragments from bacteria, which could be harmful for patient outcomes. DNA fragments from bacteria, containing the nonmethylated CpG motif, can trigger inflammation through the monocyte and lymphocyte Toll-like receptor 9, and these DNA fragments have been observed in dialysate. The fragments may transfer across the dialyzer into the patient’s bloodstream during hemodialysis treatment. During hemodiafiltration, the fragments would be introduced directly into the bloodstream. The DNA fragments may arise from biofilm in the pipes of the water system, from growth of bacteria in the water, or as contaminants in the bicarbonate and salt mixture used for preparation of dialysate. Current filtration methods, such as Diasafe filters, are not able to remove these fragments. It would be prudent to seek to reduce or eliminate these contaminants. However, the cost and effort of decreasing bacterial DNA content may ultimately require substantial facility improvements; we therefore need to fund research studies to determine if modifications to reduce bacterial DNA content are clinically warranted. This research will require methods to accurately determine the species of bacteria that contribute the DNA, since this information will allow the source to be established as biofilm, bicarbonate mixtures, or other problems in the dialysis system such as bacterial growth or leakage during water preparation. In this review, the evidence for bacterial DNA fragments will be examined and suggestions for further studies will be described.
The Cardiorenal Syndrome
Authors: Ronco Claudio , Chionh Chang-Yin , Haapio Mikko , Anavekar Nagesh S. , House Andrew , Bellomo Rinaldo
Published: January 2009

The term ‘cardiorenal syndrome’ (CRS) has increasingly been used in recent years without a constant meaning and a well-accepted definition. To include the vast array of interrelated derangements, and to stress the bidirectional nature of the heart-kidney interactions, the classification of the CRS today includes 5 subtypes whose etymology reflects the primary and secondary pathology, the time frame and simultaneous cardiac and renal codysfunction secondary to systemic disease. The CRS can generally be defined as a pathophysiological disorder of the heart and kidneys whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction in the other organ. Type I CRS reflects an abrupt worsening of cardiac function (e.g. acute cardiogenic shock or decompensated congestive heart failure) leading to acute kidney injury. Type II CRS describes chronic abnormalities in cardiac function (e.g. chronic congestive heart failure) causing progressive and permanent chronic kidney disease. Type III CRS consists in an abrupt worsening of renal function (e.g. acute kidney ischemia or glomerulonephritis) causing acute cardiac disorder (e.g. heart failure, arrhythmia, ischemia). Type IV CRS describes a state of chronic kidney disease (e.g. chronic glomerular disease) contributing to decreased cardiac function, cardiac hypertrophy and/or increased risk of adverse cardiovascular events. Type V CRS reflects a systemic condition (e.g. diabetes mellitus, sepsis) causing both cardiac and renal dysfunction. Biomarkers can help to characterize the subtypes of the CRS and to indicate treatment initiation and effectiveness. The identification of patients and the pathophysiological mechanisms underlying each syndrome subtype will help to understand clinical derangements, to make the rationale for management strategies and to design future clinical trials with accurate selection and stratification of the studied population.
Today’s Approach to the Critically Ill Patient with Acute Kidney Injury
Authors: Ricci Zaccaria , Ronco Claudio
Published: January 2009

The present review describes recent evidence on all aspects relating to acute kidney injury (AKI): epidemiology, definition, diagnosis, medical and extracorporeal therapy. AKI is often underrecognized, but its outcome still remains unfavorable. In this light, definition, classification and diagnosis of AKI are fundamental today and may be reliably based on recently proposed RIFLE (risk, injury, failure, loss of function, end-stage kidney disease) classification. Pharmacological therapy of AKI is still scarcely effective, but renal replacement therapy has progressed to a more accurate and safe treatment and new interesting high-level trials and observational studies have been performed and are reviewed and commented. In the near future, however, only increased awareness of AKI incidence and early treatment or prevention of kidney injury progression will hopefully improve outcome of critically ill patients with renal failure.
Transurethral Incision of the Bladder Neck Using KTP in the Treatment of Bladder Neck Obstruction in Women
Authors: Fu Qiang , Xu Yue-Min
Published: January 2009

Objectives: To study the results and complications of the potassium-titanyl-phosphate (KTP, green) laser during transurethral incision of the bladder neck in the treatment of female voiding dysfunction due to bladder neck obstruction. Methods: A total of 40 women (43–79 years of age) with obstruction were identified. Patients with neurogenic, traumatic, or iatrogenic causes of obstruction were excluded. Preoperative investigations included a full urodynamic examination and urethrocystoscopy. Transurethral bladder neck incision with KTP was performed in all patients. Urodynamic results, clinical improvements in voiding symptoms, and volume of bleeding were assessed. Results: Of the 40 patients, 12 had chronic urinary retention and 28 had difficult micturition. The most common findings on urodynamic study were a high voiding pressure plus low flow rate and high urethral pressure. After treatment, the lower urinary tract symptoms were resolved or improved in all patients. Urodynamic study revealed decreased voiding pressure, post-void residual urine volume, and increased maximal flow rate. Conclusions: Transurethral incision of the bladder neck is effective in relieving voiding difficulties owing to anatomic or functional bladder neck obstruction in women. KTP has great efficacy in the treatment of female voiding dysfunction due to bladder neck obstruction.
Properties in Penetrating Capsula of Transurethral Plasmakinetic Resection: Comparison with Transurethral Resection of the Prostate in an ex vivo Study
Authors: Qu Lijun , Wang Xinghuan , Wang Huaipeng , Huang Xing
Published: January 2009

Aim: As capsular perforation is still regarded as one of complications of transurethral prostatectomy, the aim of this study was to compare the properties in penetrating capsular tissue of transurethral plasmakinetic resection (PKRP) and transurethral resection of the prostate (TURP). Methods: Isolated normal saline-perfused porcine kidneys were used to determine the penetrating capsule properties of PKRP and TURP. We quantified and compared the time of cutting through renal surface during different procedures. Results: The time of perforating renal capsula induced by PKRP was longer than that by TURP (p < 0.05). As soon as the operator activated footswitch, the renal capsula was cut through by the monopolar loop. The duration was always less than 1 s in the TURP group, although sometimes the plasma-loop could not penetrate the velamen (15/40). The time of penetrating the renal surface with capsula induced by PKRP was longer than that without capsula (p < 0.05). The duration of penetrating the surface without capsula was always less than 1 s. Conclusions: With the present ex vivo model, we provided evidence that it is more difficult to penetrate capsular tissue with PKRP compared to TURP.
In vitro and in vivo Effects of Vardenafil (a PDE-5 Inhibitor) on Corpus Cavernosal Smooth Muscle Relaxation in Diabetic Rabbits
Authors: Lau D.H.W. , Mumtaz F.H. , Mikhailidis D.P. , Thompson C.S.
Published: January 2009

Introduction: Diabetes mellitus is associated with impaired cavernosal smooth muscle relaxation (CSMR) and the development of erectile dysfunction (ED). Vardenafil, a phosphodiesterase type 5 inhibitor has been used to treat ED. The aim of this study was to assess the in vitro and in vivo effects of vardenafil on diabetic rabbit CSMR. Methods: Organ bath studies were used. Results: Sodium nitroprusside (SNP)- and electrical field stimulation (EFS)-induced CSMR in diabetic rabbits given the vehicle was significantly impaired when compared with controls. The in vitro addition of vardenafil significantly enhanced SNP-induced CSMR in diabetic animals given the vehicle. SNP-induced CSMR in diabetic animals given in vivo vardenafil was significantly increased when compared with the diabetic untreated group. The in vitro addition of vardenafil significantly enhanced SNP and EFS-induced CSMR in cavernosal tissue taken from diabetic animals given vardenafil in vivo. Conclusions: The present findings suggest that the combination of in vitro and in vivo vardenafil enhance diabetic CSMR, reinforcing the use of vardenafil for the treatment of diabetes-induced ED.
Regeneration of Autotransplanted Avascular Lymph Nodes in the Rat Is Improved by Platelet-Rich Plasma
Authors: Hadamitzky Catarina , Blum Katrin S. , Pabst Reinhard
Published: January 2009

The aim of this study was to verify that subcutaneous lymph node transplantation inducing lymphatic regeneration is possible in healthy adult rats, in analogy to results obtained in other species. This rat model was used to determine the effects of lymph node fragmentation as well as sheep erythrocytes and platelet-rich plasma injection on the regeneration of the transplanted lymph nodes. The results show for the first time that the rat is an adequate model to study the regeneration of transplanted lymph nodes. Lymph node fragmentation seems to affect transplant regeneration negatively. An immune challenge by injection of sheep erythrocytes in the drainage area of the transplanted lymph nodes does not improve fragment regeneration. However, injection of syngeneic platelet-rich plasma containing several growth factors resulted in an improvement in regeneration. Lymph node fragment regeneration, although still experimental, could be relevant for lymphedema prevention. Acquired lymphedema has a high prevalence in developed countries as a consequence of the removal and/or radiotherapy of tumor-draining lymph nodes in cancer patients. This disease causes lifelong disability due to chronic swelling and increased risk of infections. It currently lacks an effective treatment.
Thromboxane A2 Contributes to the Mediation of Flow-Induced Responses of Skeletal Muscle Venules: Role of Cyclooxygenases 1 and 2
Authors: Racz A. , Veresh Z. , Erdei N. , Bagi Z. , Koller A.
Published: January 2009

Background: It has been shown that increases in intraluminal flow elicit dilation in venules, but the mediation of response is not yet clarified. We hypothesized that – in addition to nitric oxide (NO) and dilator prostaglandins (PGI2/ PGE2) – thromboxane A2 (TxA2) contributes to the mediation of flow-induced responses of venules. Methods and Results: Isolated rat gracilis muscle venules (259 ± 11 μm at 10 mm Hg) dilated as a function of intraluminal flow, which was augmented in the presence of the TxA2 receptor antagonist SQ 29,548 or the TxA2 synthase inhibitor ozagrel. In the presence of SQ 29,548, indomethacin or Nω-nitro-L-arginine methyl-ester decreased flow-induced dilations, whereas in their simultaneous presence dilations were abolished. The selective cyclooxygenase (COX) 1 inhibitor SC 560 reduced, whereas the selective COX-2 inhibitor NS 398 enhanced flow-induced dilations. Immunohistochemistry showed that both COX-1 and COX-2 are present in the wall of venules. Conclusion: In skeletal muscle venules, increases in intraluminal flow elicit production of constrictor TxA2, in addition to the dilator NO and PGI2/PGE2, with an overall effect of limited dilation. These mediators are likely to have important roles in the multiple feedback regulation of wall shear stress in venules during changes in blood flow velocity and/or viscosity.
eNOS Activation Induced by a Polyphenol-Rich Grape Skin Extract in Porcine Coronary Arteries
Authors: Madeira Socorro Vanesca Frota , Auger Cyril , Anselm Eric , Chataigneau Marta , Chataigneau Thierry , Soares de Moura Roberto , Schini-Kerth Valérie B.
Published: January 2009

Background/Aims: Drinking red wine is associated with a decreased mortality from coronary heart diseases. This study examined whether polyphenols contained in a grape skin extract (GSE) triggered the endothelial formation of nitric oxide (NO) and investigated the underlying mechanism. Methods: Vascular reactivity was assessed in organ chambers using porcine coronary artery rings in the presence of indomethacin (a cyclooxygenase inhibitor) and charybdotoxin plus apamin (inhibitors of endothelium-derived hyperpolarizing factor-mediated responses). The phosphorylation level of Src, Akt and endothelial NO synthase (eNOS) were assessed by Western blot analysis, and the formation of reactive oxygen species (ROS) was investigated using dihydroethidine and dichlorodihydrofluorescein. Results: GSE-induced endothelium-dependent relaxations were abolished by NG-nitro-L-arginine (an eNOS inhibitor) and ODQ (a soluble guanylyl cyclase inhibitor), and they were reduced by MnTMPyP, polyethyleneglycol catalase, PP2 (an inhibitor of Src kinase) and wortmannin (an inhibitor of phosphoinositide 3-kinase). GSE caused phosphorylation of Src, which was prevented by MnTMPyP. It also caused phosphorylation of Akt and eNOS, which were prevented by MnTMPyP, polyethyleneglycol catalase, PP2, wortmannin and LY294002. GSE elicited the formation of ROS in native and cultured endothelial cells, which was prevented by MnTMPyP. Conclusions: GSE causes endothelium-dependent NO-mediated relaxations of coronary arteries. This effect involves the intracellular formation of ROS in endothelial cells leading to the Src kinase/phosphoinositide 3-kinase/Akt-dependent phosphorylation of eNOS.
Lymphedema Development and Lymphatic Function following Lymph Node Excision in Sheep
Authors: Tobbia Dalia , Semple John , Baker Amy , Dumont Dan , Semple Adam , Johnston Miles
Published: January 2009

Background: Our objective was to develop an animal model of postsurgical lymphedema that would permit quantitation of edema and lymphatic function after the removal of a single popliteal lymph node in sheep. Methods: As a measure of lymph transport, 125I-human serum albumin was injected into prenodal vessels at 8, 12 and 16 weeks after nodal excision, and plasma levels of the protein tracer were used to calculate the transport rate of the tracer to blood (percent injected per hour). Edema was quantified from the circumferential measurement of the hind limbs. Results and Conclusions: Following nodal excision, the limbs became progressively more edematous up to 3 days after nodectomy. After this, the swelling decreased but had not resolved even at 16 weeks after surgery. Compared with control limbs (17.2 ± 0.6; n = 7), lymphatic function was depressed at 8 weeks after surgery (10.6 ± 1.5; n = 7). At 12 (14.4 ± 1.0; n = 7) and 16 weeks (13.9 ± 1.0; n = 6), regeneration of lymphatic vessels at the excision site helped to restore about 80% of lymphatic capacity. These techniques may be helpful in understanding the pathophysiology associated with cancer-related postsurgical lymphedema and may facilitate the development of new strategies to treat or prevent this condition.
Development of a Novel Transgenic Rat Overexpressing the P2Y2 Nucleotide Receptor Using a Lentiviral Vector
Authors: Agca Cansu , Seye Cheikh , Kashuba Benson Corinna M. , Rikka Shivaji , Chan Anthony W.S. , Weisman Gary A. , Agca Yuksel
Published: January 2009

The G protein-coupled P2Y2 nucleotide receptor (P2Y2R) is upregulated in response to stress and tissue injury and has been postulated to play a role in chronic inflammation seen in atherosclerosis, Alzheimer’s disease and Sjögren’s syndrome. The role of P2Y2R upregulation in vivo is poorly understood, in part due to the lack of a P2Y2R overexpressing animal model. The P2Y2R overexpressing transgenic rat was generated using a lentiviral vector. Rats overexpressing P2Y2R showed a significant increase in P2Y2R mRNA levels in all tissues screened as compared to nontransgenic rats. Fura 2 imaging of smooth muscle cells (SMCs) isolated from aorta indicated that the percentage of cells exhibiting increases in the intracellular free calcium concentration in response to P2Y2R agonists was significantly greater in freshly isolated SMCs from transgenic rats than wild-type controls. Histopathological examination of tissues revealed that P2Y2R overexpressing rats develop lymphocytic infiltration in lacrimal glands and kidneys as early as at 3 months of age. These rats show similarities to patients with Sjögren’s syndrome who display lymphocyte-mediated tissue damage. This transgenic rat model of P2Y2R overexpression may prove useful for linking P2Y2R upregulation with chronic inflammatory diseases, neurodegenerative diseases and Sjögren’s syndrome.
Neuroanatomy of Apathy and Disinhibition in Frontotemporal Lobar Degeneration
Authors: Massimo Lauren , Powers Chivon , Moore Peachie , Vesely Luisa , Avants Brian , Gee James , Libon David J. , Grossman Murray
Published: January 2009

Objective: To investigate the neural basis for the behavioral symptoms of frontotemporal lobar degeneration (FTLD) that cause the greatest caregiver distress. Background: FTLD is a progressive neurodegenerative disease associated with behavioral disturbances. Group studies have related these behaviors to volume loss on MRI. Methods: Forty caregivers of patients with the clinical diagnosis of FTLD completed the Neuropsychiatric Inventory. Twelve neuropsychiatric symptoms and the associated caregiver distress were assessed. Optimized voxel-based morphometry identified significant atrophy in subgroups of FTLD patients with isolated behavioral symptoms corresponding to the most distressing behaviors, and we correlated cortical atrophy directly with these distressing behavioral disorders in an unbiased group analysis. Results: The greatest stressors for caregivers were apathy and disinhibition (p < 0.005 for both contrasts). Partially distinct areas of cortical atrophy were associated with these behaviors in both individual patients with these symptoms and group-wide analyses, including the dorsal anterior cingulate cortex and dorsolateral prefrontal cortex in apathetic patients, and the medial orbital frontal cortex in disinhibited patients. Conclusions: Caregiver stress in families of FTLD patients is due in large part to apathy and disinhibition. The anatomic distribution of cortical loss corresponding to these distressing social behaviors includes partially distinct areas within the frontal lobe.
Functional Outcome in Delusional Alzheimer Disease Patients
Authors: Fischer Corinne E. , Verhoeff Nicolaas P.L.G. , Churchill Katie , Schweizer Tom A.
Published: January 2009

Background: In spite of the prevalence of delusions in Alzheimer’s disease (AD) and their association with poor outcomes, there has been little study of the impact of delusions on real-world functioning. Method: A number of databases, including Psychlit and Medline, were searched using the keywords: delusions, functional outcomes, activities of daily living, dementia, and Alzheimer’s disease. Studies were included in the review if they were in English, restricted to patients with AD, and addressed delusions and function. Results: The review yielded a total of 6 studies, 3 of which showed a correlation between delusions and real-world functioning and 3 of which did not. Conclusion: A critical analysis of the existing studies suggests that there may be an association between delusions and impaired real-world functioning. We believe that 2 of the 3 negative studies did not show an association due to issues relating to study design and the use of measures insensitive to executive impairment. This review highlights the future need for more scientifically rigorous studies to clarify this association, so as to ultimately improve treatment outcomes for patients.
Association of Cognitive Impairment with Serum Lipid/Lipoprotein among Chinese Nonagenarians and Centenarians
Authors: Huang Chang-Quan , Dong Bi-Rong , Wu Hong-Mei , Zhang Yan-Ling , Wu Jin-Hui , Lu Zhen-Chan , Flaherty Joseph H.
Published: January 2009

The association of cognitive impairment with abnormal levels of serum lipid/lipoprotein in the elderly, in whom there are differences between the old aged 65–84 years and the oldest old aged 85 years or above, has been confirmed by previous studies. However, there are no relevant data from a Chinese oldest old population. In the present study, we observed an association of cognitive impairment with abnormal levels of serum lipid/lipoprotein among very old people using a Chinese cohort aged 90–108 years. The population included 709 unrelated Chinese nonagenarians and centenarians (67.8% women, mean age 93.8 years). The mean score of cognitive function (measured with the 30-item Mini-Mental State Examination, MMSE) was 14.9 (SD 6.0). Comparing abnormal with normal levels of serum lipid/lipoprotein (including triglycerides, total cholesterol, high-density lipoprotein and low-density lipoprotein), in both genders, the odds ratio of cognitive impairment was statistically insignificant. There were no significant differences in levels of lipid/lipoprotein between subjects with and without cognitive impairment. Pearson correlation showed that MMSE scores were not significantly correlated with levels of lipid/lipoprotein. In summary, we found that levels of serum lipid/lipoprotein were not directly correlated with cognitive impairment among Chinese nonagenarians and centenarians.
Diffusion-Weighted MRI in the Diagnosis of Cholesteatomas
Authors: Teschner M. , Hinz K. , Stöver T. , Lenarz T. , Becker H.
Published: January 2009

Objective: The diagnosis of a cholesteatoma can be difficult in cases with an intact tympanic membrane. The aim of our study was to examine whether diffusion-weighted MRI can confirm the diagnosis of a cholesteatoma. Study Design: A preoperative diffusion-weighted MRI (echo-planar imaging) scan of the temporal bone was performed in 31 patients with clinically suspected cholesteatoma. The diagnosis was confirmed by pathohistological examination in 18 cases, while the majority of the remaining patients showed chronic otitis media without cholesteatoma. Results: In 3 out of 18 patients with histologically confirmed cholesteatoma, diffusion-weighted imaging produced a hyperintense signal. Another 4 of the 18 cases had a questionable positive result. No increased signal was observed in 11 of these 18 patients. Of 12 patients without a cholesteatoma, 2 showed a positive signal while a questionable hyperintense signal was observed in 5 patients. Conclusions: According to our present findings, diffusion-weighted MRI (echo-planar imaging) can – with a low sensitivity and specificity – be helpful in individual cases in provisionally diagnosing a cholesteatoma in association with standard MRI and high-resolution CT, even though the lack of a hyperintense signal in diffusion-weighted MRI does not exclude a cholesteatoma.
Measurement of Pupil Centroid Shift and Cyclotorsional Displacement Using Iris Registration
Authors: Park Shin Hae , Kim Minjung , Joo Choun-Ki
Published: January 2009

Background/Aims: To estimate the amount and nature of pupil centroid shift and cyclotorsion occurring between preoperative wavefront measurement and refractive surgery. Methods: This retrospective study comprised 183 eyes of 92 patients who had wavefront-guided LASIK using iris registration. We analyzed the pupil centroid shift and cyclotorsional displacement occurring between preoperative wavefront measurements and during the laser procedure. The eyes were measured by the WaveScan® Wavefront® system (VISX, Santa Clara, Calif., USA) and refractive surgery was performed with the VISX STAR S4 excimer laser system. Results: The mean magnitude of shifts in the location of pupil center was 0.26 ± 0.16 mm horizontally, 0.20 ± 0.16 mm vertically and 0.37 ± 0.13 mm vectorally. 162 eyes (88.5%) experienced more than 0.2 mm of shift. The mean amount of torsion was 2.58 ± 1.56° for 83 eyes showing incyclotorsion and 2.94 ± 1.87° for 100 eyes showing excyclotorsion. 117 eyes (63.9%) experienced more than 2° of cyclotorsion and 21 eyes (11.5%) experienced more than 5° of cyclotorsion. Conclusions: Pupil centroid shift and cyclotorsion occur in the majority of eyes undergoing laser treatment. The amount of pupil centroid shift and cyclotorsion shown in this study is considerable. Accurate compensation for cyclotorsion and pupil centroid shift may maximize the potential of visual quality of customized ablations.
Polymorphisms in the Nonmuscle Myosin Heavy Chain 9 Gene (MYH9) Are Associated with Albuminuria in Hypertensive African Americans: The HyperGEN Study
Authors: Freedman Barry I. , Kopp Jeffrey B. , Winkler Cheryl A. , Nelson George W. , Rao D.C. , Eckfeldt John H. , Leppert Mark F. , Hicks Pamela J. , Divers Jasmin , Langefeld Carl D. , Hunt Steven C.
Published: January 2009

Background:MYH9 is a podocyte-expressed gene encoding nonmuscle myosin IIA that is associated with idiopathic and human immunodeficiency virus-associated focal segmental glomerulosclerosis (FSGS) and hypertensive end-stage renal disease in African Americans. Methods: Four single nucleotide polymorphisms comprising the major MYH9 E1 risk haplotype were tested for association with estimated glomerular filtration rate (eGFR) and urine albumin:creatinine ratio (ACR) in 2,903 HyperGEN participants (1,458 African Americans (AA) in 895 families and 1,445 European Americans (EA) in 859 families) to determine the role of MYH9 in subclinical nephropathy. Association analyses employed general linear models in unrelated probands and generalized estimating equations in families. Adjustment was performed for age, sex, diabetes, BMI, medications, and mean arterial pressure separately in each race. Results: Mean (SD) eGFR and ACR were 74.3 (16.0) ml/min/1.73 m2 and 20.3 (119.9) mg/g in EA, and 88.6 (20.9) ml/min/1.73 m2 and 76.8 (394.5) mg/g in AA (both p < 0.0001 across ethnicities). Urine ACR was associated with rs3752462 (p = 0.01) and rs4821481 (p = 0.05) in unrelated AA and with rs4821481 (p = 0.03), rs2032487 (p = 0.04) and the E1 3224 haplotype (p = 0.013) in AA families. Single nucleotide polymorphisms and the haplotype were not associated with ACR in EA or with eGFR in either ethnic group. Conclusions:MYH9 variants are associated with albuminuria in hypertensive AA. The strength of the association was weaker than that in FSGS and hypertensive end-stage renal disease. MYH9 risk variants appear to be associated with primary FSGS with secondary hypertension, although nephrosclerosis may develop in response to hypertension in subjects homozygous for the MYH9 E1 risk haplotype.
Cold and Hot Snare Endoscopic Techniques for Removal of the Bravo pH Monitoring Capsule
Authors: de Hoyos Andrés , Esparza Edgar Alain , Loredo Maria Lilia
Published: January 2009

Background: Currently, use of the Bravo capsule is a very common method for evaluating the gastroesophageal reflux because it has the advantage of being an intraesophageal catheter-free system. However, endoscopic removal of the capsule is necessary when technical problems or severe discomfort are present. Most frequently, endoscopists solve this problem by nudging the device with the tip of the endoscope to dislodge it; others have used a cold snare to produce traction on the capsule, and then tear the probe off. These techniques however are not free of complications. We report here the cold and hot snare techniques used in 4 of our patients, which resulted in the successful removal of the capsule without complications. Methods: The polypectomy cold snare procedure is a typical polypectomy method. The cold snare loops the mucosal pedicle and tightly closes it until sectioning is achieved. In the hot snare technique, a monopolar coagulating current is added to the previous procedure, making the resection more feasible when the cold snare is not sufficient. Finally, in both situations, the probe is removed from the esophagus with the same snare. Conclusions: The cold and hot snare techniques are safe and simple endoscopic procedures when the removal of the Bravo capsule is required. We recommend the cold snare method as a first option and the hot snare method in case the former fails.
Delirium after Abdominal Surgery at a Surgical Ward with a High Standard of Delirium Care: Incidence, Risk Factors and Outcomes
Authors: Koebrugge Boukje , Koek Huiberdina L. , van Wensen Remco J.A. , Dautzenberg Paul L.J. , Bosscha Koop
Published: January 2009

Background: Although delirium is a common problem in elderly patients undergoing surgery, standard delirium care is not available in all wards. The object of this study was to determine the incidence, risk factors and outcomes of postoperative delirium among patients aged 65 and above undergoing elective abdominal surgery at a surgical ward with a high standard delirium care. Methods: Prospective descriptive survey in 71 patients. The Delirium Observation Scale was used to screen for delirium. Patients were classified as having a delirium if they met the DSM IV-criteria. Delirious and nondelirious patients were compared and associated risk factors were calculated using logistic regression analyses. Results: Incidence of postoperative delirium was 24%. Univariate analysis showed that age above 74 years, CST score, ASA score, length of ICU stay, length of hospital stay and number of complications were significant risk factors for delirium. Older age, however, was the only significant risk factor in multivariate analysis (OR 1.16; 95% CI 1.00–1.35; p = 0.05). Lastly, mortality was significantly higher in the delirium group (29.4 vs. 3.7%; p = 0.001). Conclusion: At a surgical ward with high standard delirium care, the incidence of delirium was 24% and mortality was higher in delirious patients undergoing elective abdominal surgery.
Survival of Patients with T3 Stage III Rectal Cancer Is Significantly Worse than T2 Stage III Rectal Cancer
Authors: Hotta Tsukasa , Takifuji Katsunari , Yokoyama Shozo , Matsuda Kenji , Higashiguchi Takashi , Tominaga Toshiji , Oku Yoshimasa , Nasu Toru , Tamura Koichi , Yamaue Hiroki
Published: January 2009

Background: The prognosis of T1 plus T2 stage III rectal cancer patients is better than that of T3 stage III rectal cancer patients. However, it is thought that T1 rectal cancer patients have a better prognosis than T2 rectal cancer patients. Aim: This study attempted to clarify the difference of the short- and long-term outcomes in T2 and T3 stage III rectal cancer patients deleting T1 cancer. Methods: The study demonstrated the potential predictors of the survival after surgery, the factors associated with T3 and T2, and the recurrence sites in 134 patients with stage III rectal cancer who underwent surgery, including 111 patients with T3 and 23 patients with T2. Results: The disease-free survival (DFS) of the T3 stage III patients was worse than the T2 stage III patients (5-year DFS rates, 52 vs. 78%; 10-year DFS rates, 43 vs. 78%; p =0.044). The maximum tumor size and operative blood loss were significant tumor characteristics associated with the depth of invasion (p =0.007,p =0.011,respectively). There was no significant difference in the recurrence sites after surgery between the two groups. Conclusion: As a result, a more detailed subdivision for stage III rectal cancer is considered necessary.
A Model for Fine Mapping in Family Based Association Studies
Authors: Boehringer Stefan , Pfeiffer Ruth M.
Published: January 2009

Genome wide association studies for complex diseases are typically followed by more focused characterization of the identified genetic region. We propose a latent class model to evaluate a candidate region with several measured markers using observations on families. The main goal is to estimate linkage disequilibrium (LD) between the observed markers and the putative true but unobserved disease locus in the region. Based on this model, we estimate the joint distribution of alleles at the observed markers and the unobserved true disease locus, and a penetrance parameter measuring the impact of the disease allele on disease risk. A family specific random effect allows for varying baseline disease prevalences for different families. We present a likelihood framework for our model and assess its properties in simulations. We apply the model to an Alzheimer data set and confirm previous findings in the ApoE region.