bluuebunny/crossref_metadata_2025 huggingface dataset:
Is an assay for simultaneous detection of hepatitis C virus core antigen and antibody a valuable alternative to nucleic acid testing?
Authors: Laperche Syria , Elghouzzi Marie‐Hélène , Morel Pascal , Asso‐Bonnet Marianne , Le Marrec Nadine , Girault Annie , Servant‐Delmas Annabelle , Bouchardeau Françoise , Deschaseaux Marie , Piquet Yves
Published: October 2005

BACKGROUND: A new enzyme immunoassay based on the simultaneous detection of nucleocapsid proteins of hepatitis C virus (HCV) and anti‐HCV (Monolisa HCV antigen‐antibody Ultra, Bio‐Rad) was evaluated as an alternative to nucleic acid testing (NAT) for the diagnosis of HCV infection during the window period in blood donations.

STUDY DESIGN AND METHODS: The study included 107 sequential samples from 10 HCV seroconversion commercial panels; 81 samples were in the preseroconversion phase, and 26 were collected after seroconversion. All samples were tested with HCV antigen‐antibody assay and the two minipool (MP) NAT procedures that are routinely used in France (transcription‐mediated amplification in pools of 8 and COBAS AmpliScreen HCV test [Roche Diagnostic] in pools of 24 donations).

RESULTS: From the 44 samples collected during window period that were MP‐NAT–positive, 31 (70.5%) were also positive with the Monolisa HCV antigen‐antibody assay. The mean delay in detecting HCV infection between these two methods was 5.1 days (range, 0‐24 days). The Monolisa HCV antigen‐antibody assay led to a reduction in the window period of 26.8 days (range, 0‐72 days). All samples collected after seroconversion were detected with the HCV antigen‐antibody assay. The specificity analyzed in 2503 consecutive blood donations was estimated at 99.88 percent.

CONCLUSION: This new developed assay presents an improvement for the detection of HCV infection, especially in the early phase of infection when antibodies are undetectable. Although less sensitive than NAT, this assay could be a suitable solution for blood screening in developing countries where NAT (or HCV core antigen–specific assay) is not affordable or its implementation is not feasible.
Intraoperative Testing of the Implantable Cardioverter‐Defibrillator: How Much Is Enough?
Authors: PIRES LUIS A. , JOHNSON KATRINA M.
Published: October 2005

Introduction: Defibrillation testing of the implantable cardioverter‐defibrillator (ICD) is considered a standard and required practice at the time of implantation. How much testing, if any in some cases, should be performed, however, remains unknown.

Methods and Results: Included in this retrospective analysis were 835 patients (77% men; age 65 ± 13 years) who received transvenous ICDs between January 1996 and December 2003. One hundred twenty‐nine (15.5%) had intraoperative defibrillation threshold (DFT) testing, 503 (60.2%) had limited defibrillation safety margin testing, and 203 (24.3%) had no defibrillation testing. We compared the outcome (success of ICD therapies against spontaneous VT/VF events and survival) of the three groups of patients, who in some respects had important clinical differences. The success of the first delivered shocks against VT/VF was similar for DFT (91%), safety margin testing (91%), and no‐testing (92%) groups; and the second shocks terminated the remaining episodes in all three groups. Sudden‐death‐free survival rates were similar in the three groups, however, the overall long‐term survival rate was significantly lower in the no‐testing group (58%) than in the DFT (74%) and safety margin testing (69%) groups (P < 0.0005). Multivariate analysis found no strong predictors of sudden death, but there were several independent predictors of overall mortality including lack of ICD testing (HR: 2.031, CI: 1.253–3.290, P = 0.004).

Conclusion: In this select patient cohort, success of ICD therapies and sudden‐death‐free survival were similar in patients who had DFT, safety margin testing, and no testing, but overall survival was significantly lower in the no‐testing group. Thus in the absence of prospective mortality data, a minimum of safety margin ICD testing should remain standard practice.
The Mechanisms of an Increased Dominant Frequency in the Left Atrial Posterior Wall During Atrial Fibrillation in Acute Atrial Dilatation
Authors: HUANG JIN‐LONG , TAI CHING‐TAI , LIN YENN‐JIANG , TING CHIH‐TAI , CHEN YING‐TSUNG , CHANG MAU‐SONG , LIN FAN‐YUE , LAI WEN‐TER , CHEN SHIH‐ANN
Published: October 2005

Background: Previous studies have shown that the highest dominant frequency (DF) is located in the left atrium (LA) during atrial fibrillation (AF) in pacing‐induced AF. However, there have been few studies on the mechanisms of the increased DF of AF during acute atrial dilatation. The purpose of this study was to investigate the mechanisms of the increased maximal DF (max DF) in pacing‐induced AF during acute atrial dilatation.

Methods: In eight Langendorff‐perfused canine hearts (26 ± 2 kg), noncontact balloon catheters were placed into the right atrium (RA) and LA, respectively. AF was induced by extrastimulation pre‐ and postdilatation in the atrium (0 and 15 cm H2O, respectively). Fast Fourier transformation analysis was performed to analyze the max DF and harmonic index (HI) from the bi‐atrial unipolar virtual electrograms during AF. The fibrillation cycle lengths were obtained from different atrial sites. The number of wavefronts was analyzed during AF. The frequency of regional splitting was defined as the number of wavefront splits per second in different atrial regions during AF. The percentage of the low‐voltage zones (<0.5 mV) was defined as the ratio of the area of the low‐voltage zones to the total atrial surface area.

Results: The DF was measured during AF. The shortest fibrillation cycle length was located in the LA posterior wall and became shorter during acute atrial dilatation. The max DF was located in the LA posterior wall and increased during acute atrial dilatation (7.1 ± 0.8 vs 8.8 ± 2.1, P = 0.02). The max DF of the LA correlated with the wavefront number (r = 0.797, P < 0.001 predilatation; r = 0.860, P < 0.001 postdilatation). The splitting of wavefronts facilitated the formation of new wavefronts. During acute atrial dilatation, the frequency of regional splitting was closely correlated with the percentage of the low‐voltage zones (r = 0.876, P < 0.001). Furthermore, the LA posterior wall had a higher percentage of the low‐voltage zones than the other sites.

Conclusion: In acute atrial dilatation, the percentage of the low‐voltage zones increased, especially in the LA posterior wall, which correlated with the regional splitting of the AF wavefronts. The increase in the splitting facilitated the formation of new wavefronts and resulted in a higher max DF during acute atrial dilatation.
Use of a Coronary Sinus Lead and Biventricular ICD to Correct a Sensing Abnormality in a Patient with Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy
Authors: BILCHICK KENNETH C. , JUDGE DANIEL P. , CALKINS HUGH , MARINE JOSEPH E.
Published: October 2005

Implantable cardioverter defibrillators (ICDs) are frequently offered to patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C). Yet ICDs in these patients may be complicated by poor sensed amplitudes resulting from fatty and fibrous tissue replacement of right ventricular myocardium. We present the case of a patient with ARVD/C who had inappropriate detection of ventricular tachycardia with a single‐chamber ICD due to poor sensed right ventricular amplitudes. We discuss how the use of a bipolar coronary sinus lead and a biventricular ICD generator with a novel header configuration solved the problem.
Ketoconazole Induced Torsades de Pointes Without Concomitant Use of QT Interval‐Prolonging Drug
Authors: MOK NGAI‐SHING , LO YING‐KEUNG , TSUI PING‐TIM , LAM CHING‐WAN
Published: October 2005

Ketoconazole is not known to be proarrhythmic without concomitant use of QT interval‐prolonging drugs. We report a woman with coronary artery disease who developed a markedly prolonged QT interval and torsades de pointes (TdP) after taking ketoconazole for treatment of fungal infection. Her QT interval returned to normal upon withdrawal of ketoconazole. Genetic study did not find any mutation in her genes that encode cardiac IKr channel proteins. We postulate that by virtue of its direct blocking action on IKr, ketoconazole alone may prolong QT interval and induce TdP. This calls for attention when ketoconazole is administered to patients with risk factors for acquired long QT syndrome.
Biventricular Pacing Has an Advantage over Left Ventricular Epicardial Pacing Alone to Minimize Proarrhythmic Perturbation of Repolarization
Authors: HARADA MASAHIDE , OSAKA TOSHIYUKI , YOKOYAMA ERIKO , TAKEMOTO YOSHIO , ITO ATSUSHI , KODAMA ITSUO
Published: October 2005

Introduction: Cardiac resynchronization therapy (CRT) by simultaneous biventricular pacing is now widely accepted as a new therapeutic option for patients with severe congestive heart failure (CHF). Recent studies have shown comparable hemodynamic benefits of left ventricular (LV) pacing alone. The clinical usefulness of CRT, however, might be compromised by potential exaggeration of arrhythmogenic substrates through a modification of ventricular repolarization.

Methods and Results: We compared ECG parameters during sinus rhythm (SR), atrioventricular synchronous pacing at the right ventricular apex (RVendP), at LV epicardium (LVepiP), and at both sites (BiVP) in acute homodynamic studies of 14 CHF patients scheduled for CRT (QRS duration = 144 ± 23 msec, LVEF = 27 ± 10%). The maximum rate of increase in LV pressure (LVdp/dtmax) was decreased significantly during RVendP, whereas it was increased similarly during LVepiP and BiVP compared with SR. QTc was increased during RVendP (by 10.2%) and LVepiP (by 26.1%). QTc dispersion (QTcmax‐QTcmin in the six precordial leads) was also increased during LVepiP (by 66.5%). These parameters were unaffected during BiVP. JTc was unchanged, and the interval from the peak to the end of the T wave (Tcpeak‐end) was increased slightly (by 19.3%) during RVendP. Both JTc and Tcpeak‐end were increased dramatically during LVepiP (by 18.2% and 55.4%, respectively), but increased only modestly during BiVP (by 6.6% and 15.8%, respectively).

Conclusions: LVepiP causes much greater increase in spatial dispersion of ventricular repolarization than BiVP in CHF patients. BiVP may have a substantial advantage over LVepiP to minimize the proarrhythmic perturbation of ventricular repolarization in association with CRT.
Substrate in the Interventricular Septum for Left Ventricular and Right Ventricular Outflow Tract Tachycardia: Ablation from the Right Side of the Septum
Authors: REITHMANN CHRISTOPHER , REMP THOMAS , STEINBECK GERHARD
Published: October 2005

Simultaneous epicardial and endocardial mapping demonstrated that in a substantial number of ventricular tachycardias (VTs) endocardial, intramural, and epicardial structures are involved in the substrate of the reentrant circuits. Both right and left ventricular breakthrough has also been described during VT originating in the interventricular septum. We report the case of a patient with a nonischemic left ventricular aneurysm presenting with a left ventricular outflow tract (LVOT) tachycardia and a right ventricular outflow tract (RVOT) tachycardia. Mapping from the anterior interventricular vein and the endocardium of the RVOT revealed mid‐diastolic potentials at the epicardium of the LVOT and the endocardium of RVOT, where the criteria of central isthmus sites could be demonstrated. Ablation targeting an isolated late potential during sinus rhythm in RVOT eliminated both the LVOT tachycardia and the RVOT tachycardia. In this patient with a nonischemic left ventricular aneurysm, the substrate of a LVOT tachycardia and RVOT tachycardia is described, and successful catheter ablation of the right and left ventricular tachycardia from the septal wall of RVOT is reported.
Left Ventricular Lead Placement Within a Coronary Sinus Side Branch Using Remote Magnetic Navigation of a Guidewire: A Feasibility Study
Authors: RIVERO‐AYERZA MAXIMO , THORNTON ANDREW S. , THEUNS DOMINIC A.M.J. , SCHOLTEN MARCOEN F. , MEKEL JORIS M. , RES JAN , JORDAENS LUC J.
Published: October 2005

Background: A novel magnetic navigation system (MNS) allowing remote guidance of catheters and guidewires might assist in implantation of left ventricular (LV) pacing leads.

Objective: To assess the feasibility of deploying a LV pacing lead into a coronary sinus (CS) side branch using a magnetically guided wire and of performing the procedure without a CS guiding sheath.

Methods: Twenty‐one patients were included in this study. Nine underwent CRT device implantation using a MNS to steer the guidewire (MNS group) while 12 patients were conventionally implanted (control group). In 6 patients in the MNS group, the procedure was performed using a CS guiding sheath. In 3 others, the decision was to perform the procedure without a CS sheath. In these patients the wire was advanced manually, while the external magnets oriented it toward the CS os. In the CS, “vector based” navigation was used to guide the wire to the desired side branch.

Results: In all 9 patients in the MNS group, the target vessel could be successfully engaged by the magnetically guided wire. In 7, the LV lead was lodged in the target vessel. In 2 patients, the LV lead was repositioned in an anterolateral side branch due to instability or inability to engage the vessel with it. Mean total procedure time was 164 ± 58 minutes (without sheath 229 ± 52 vs with sheath 132 ± 26 minutes; P = 0.007). Mean fluoroscopy time was 28 ± 9 minutes. For control patients, the procedure and fluoroscopy time were similar (144 ± 41 minutes and 26 ± 12 minutes, respectively). No major complications occurred.

Conclusion: LV lead implantation can be performed using a remote magnetically steered guidewire. Though the lead could be implanted without a CS guiding sheath, longer procedure times were required.
Factors influencing low‐molecular‐weight solute clearance during hemodialysis
Authors: Huang Zhongping , Clark William R , Gao Dayong
Published: October 2005

The relationship between delivered urea Kt/V and survival has raised concerns in recent outcome trials in chronic dialysis patients. Nevertheless, measurement of delivered small solute clearance remains the most common approach to quantify therapy. The purpose of this review is to provide an overview of the numerous factors influencing small solute clearance during hemodialysis. Although the focus of the review is on the manner in which dialyzer characteristics influence small solute clearances, factors related to other aspects of the extracorporeal circuit and to the patient will also be discussed.
Effect of mineralocorticoids on interdialytic weight gain in hemodialysis patients with perdialytic hypotension
Authors: Mercadal Lucile , Petitclerc Thierry
Published: October 2005

Fludrocortisone is recommended in patients with orthostatic hypotension and a benefit has been suggested in hemodialysis patients with severe hypokaliemia. We report 2 patients who suffered from chronic severe perdialytic hypotension resistant to midodrine and who were treated in a long‐term period with fludrocortisone. A rise of post‐dialytic BP was observed with a decrease of the interdialytic weight gain (IWG). We suggest that the IWG decrease is induced by a lessening of the renin angiotensin aldosterone system that could be less stimulated at the end of the dialysis session because of a better‐preserved arterial pressure. The decrease of angiotensin could lessen the feeling of thirst.
Reflex sympathetic dystrophy syndrome due to arteriovenous fistula
Authors: Unek Ilkay Tugba , Birlik Merih , Cavdar Caner , Ersoy Rifki , Onen Fatos , Celik Ali , Camsari Taner
Published: October 2005

A patient with end‐stage renal disease presented with reflex sympathetic dystrophy syndrome (RSDS) on her left hand 1 month after arteriovenous fistula (AVF) surgery. Magnetic resonance angiography revealed steal syndrome at the AVF level. Bone scintigraphy revealed early‐stage RSDS. We considered that arterial insufficiency because of steal phenomenon following AVF surgery and underlying occlusive arterial disease triggered RSDS development.
The morbidity and cost implications of hemodialysis clinical performance measures
Authors: O'Connor Andrew S , Wish Jay B , Sehgal Ashwini R
Published: October 2005

Clinical performance measures, including dialysis dose, hemoglobin, albumin, and vascular access, are the focus of monitoring and quality improvement activities. However, little is known about the implications of clinical performance measures for hospital utilization and health care costs. We obtained clinical performance measures and hospitalization records for a national random sample of 10,650 hemodialysis patients and analyzed the relationship between changes in clinical performance measures and hospital utilization after adjustment for patient demographic and medical characteristics.

Higher hemoglobin, higher albumin, and fistula or graft use were independently associated with fewer hospitalizations, fewer hospital days, and decreased Medicare inpatient reimbursement. For example, a 0.5 g/dL higher hemoglobin, a 0.25 g/dL higher albumin, fistula use, and graft use were associated with hospitalization rate ratios of 0.90 (95% confidence interval 0.85, 0.96), 0.64 (0.53, 0.77), 0.60 (0.52, 0.69), and 0.79 (0.71, 0.89), respectively. Moreover, there was a 2–3‐fold variation in hospital utilization across end‐stage renal disease networks that was still evident after adjustment for patient characteristics and clinical performance measures. Clinical performance measures, especially albumin and vascular access, are strongly associated with hospital utilization and health care costs. These results highlight the importance of targeting nutrition and vascular access in quality improvement efforts. The marked variation in hospital utilization across networks deserves further examination.
Prevalence of transfusion‐transmitted virus infection in patients on maintenance hemodialysis from New Delhi, India
Authors: Chattopadhyay Saket , Rao Sunita , Das Bhudeb Chandra , Singh Narinder Pratap , Kar Premashis
Published: October 2005

Transfusion‐transmitted virus (TTV) has been reported from a number of hemodialysis (HD) units from various countries throughout the world. TTV has been associated with liver diseases, viral hepatitis B, and C. Clinical details and information regarding TTV prevalence from India are insufficient. The prevalence and clinical significance of TTV infection were studied in New Delhi, India in HD patients. Serum samples were derived from 75 patients on maintenance HD, and 75 age‐ and sex‐matched voluntary blood donors were examined for TTV viremia by nested polymerase chain reaction (PCR) using primers derived from UTR (A) region of the TTV genome. The prevalence of TTV DNA in patients on HD (83%) was significantly (p<0.05) higher than in blood donors (43%). Clinical background including the mean age, sex, mean duration of HD, and mean alanine aminotransferase (ALT) levels did not differ significantly between TTV DNA‐positive and ‐negative HD patients. Fifty‐four (72%) TTV‐positive HD patients and 7 (56%) TTV‐negative HD patients had blood transfusion histories (p>0.05). Among TTV‐positive patients, Hepatitis B virus (HBV) co‐infection was present in 14.2% cases while hepatitis C virus (HCV) co‐infection was absent. Persistent elevation of ALT levels was observed in 7(9.3%) HD patients; 3 (43%) of them were TTV positive and 4 (57%) were TTV negative (p>0.05). All 3 TTV‐positive patients with elevated ALT levels were co‐infected with HBV. Patients with TTV infection alone showed normal ALT levels. Prevalence of TTV infection is high in North Indian patients on maintenance HD. Also, none of the exclusively TTV DNA‐positive patients had clinical or biochemical signs of liver disease. TTV seems to spread through parenteral routes. More often, TTV seems to be associated with parenterally transmitted virus HBV, indicating a parenteral mode of TTV transmission. The pathogenicity of TTV remains unclear from the present study.
Hyperphosphatemia among end‐stage renal disease patients in developing countries: A forgotten issue?
Authors: Afifi Adel , El‐Sayed Hesham , El‐Setouhi Maged , Ahmed Hayam , Khalifa Noha
Published: October 2005

The prevalence of hyperphosphatemia and increased calcium–phosphorus product has never been evaluated in a large multicenter study in a developing country. Our aim is to study the prevalence of hyperphosphatemia in 38 HD centers in Egypt (as an example of a developing country) and to correlate it with different co‐morbid conditions and the patient's demographic data. This is a cross‐sectional study conducted on 1005 chronic kidney disease stage 5 patients (CKD‐stage 5) on HD for a period of more than 1 year in 38 dialysis centers in Egypt. All patients were receiving calcium‐based salts as a phosphate binder. Hyperphosphatemia and increased calcium–phosphorus product were evaluated and correlated with different parameters including age, sex, knowledge by diet parameters, HD session duration, the frequency of HD per week, the type of dialysis membrane, the surface area of the dialyzer, dialyzer phosphorus clearance (phosphorus KoA), and the type of dialysate. Other co‐morbid medical conditions and evidence of IHD were also investigated. Hyperphosphatemia was present in 69.1% of cases and a high calcium–phosphorus product was present in 30.2%. A higher calcium–phosphorus product was found among males. 83.2% of those with a poor knowledge by diet parameters had hyperphosphatemia compared with 67.6% in patients with a satisfactory knowledge by diet parameters. 72.3% of patients using a membrane with low‐to‐medium clearance had hyperphosphatemia, compared with 67.2% using a membrane with a high clearance. Seventy‐two percent of patients with IHD were hyperphosphatemic compared with 67.6% of the non‐ischemic patients. Hyperphosphatemia is a major problem in dialysis patients in developing countries, reflecting differences from developed countries regarding dietary habits, ethnic factors, dialysis quality, types of dialysis membranes, as well as economic factors hampering the use of the more expensive phosphate binders. Extended dialysis hours may be a good alternative solution in developing countries.
Role of platelet factor 4–heparin complex antibody (HIT antibody) in the pathogenesis of thrombotic episodes in patients on hemodialysis
Authors: Nakamoto Hidetomo , Shimada Yoshihiro , Kanno Tatsuhiko , Wanaka Keiko , Matsuo Takefumi , Suzuki Hiromichi
Published: October 2005

Heparin‐induced thrombocytopenia (HIT) is a severe complication in patients on hemodialysis (HD). It has been reported that platelet factor‐4 (PF‐4)–heparin complex antibody (HIT antibody) plays an important role in the pathogenesis of this serious complication. In the present study, we investigated the role of HIT antibody in the pathogenesis of thrombotic complications including shunt failure, cerebrovascular disease (CVD) and atherosclerosis in patients on dialysis. Plasma concentration of HIT antibody in patients on HD was 0.143±0.008 (n=105). This was significantly higher in patients on continuous ambulatory peritoneal dialysis (CAPD: 0.087±0.006, p=0.0008, n=22) and in non‐dialysis patients (0.113±0.011, p=0.0011, n=12). There was a significant negative correlation between HIT antibody and the duration of dialysis. However, no significant correlation was found between HIT antibody and other factors including age, dose of heparin, platelet count and hemoglobin. There was a significant correlation between the number of failed arteriovenous fistula and HIT antibody levels. In addition, in patients with a history of CVD, plasma concentrations of HIT antibody were significantly higher compared with patients without CVD (CVD(+): 0.200±0.029 vs. (−): 0.127±0.005, p<0.0001). It is possible that genetic factors may also play a role in the expression of HIT antibody. From these data, it appears possible that HIT antibody plays an important role in the pathogenesis of thrombosis in patients on HD. Further studies are needed to clarify the role of HIT antibody in the pathogenesis of thrombotic episodes in these patients.
Inhibitory effect of PPAR‐Gamma activator on IL‐6 and mPGES protein expression in PBMC induced by homocysteine
Authors: Peng Youming , Liu Hong , Liu Fuyou , Wang Haitao , Liu Yinghong , Duan Shaobin
Published: October 2005

The objective was to investigate the relationship between homocysteine (HCY), peroxisome proliferator‐activated receptors (PPAR)‐γ and the expression of interleukin 6 (IL‐6) and microsomal prostaglandin E synthase (mPGES) by peripheral blood mononuclear cell (PBMC) culture in vitro, as well as to look at the intervention with HCY and PPAR‐γ activators (troglitazone and rosiglitazone). PBMC were isolated from venous blood of normal volunteers and incubated with HCY and PPAR‐γ activator of varying concentrations for 24 hr. The supernatant of the culture medium was collected in order to determine the IL‐6 and mPGES levels by ELISA assay. The results show that the expression of IL‐6 and mPGES in the HCY experimental group was significantly higher than that in the control group (p<0.01 and p<0.05, respectively). Additionally, the IL‐6 and mPGES levels rose with the increase of HCY in a dose‐dependent manner (p<0.01 and p<0.05, respectively). PPAR‐γ activator could significantly inhibit the increase of IL‐6 and mPGES induced by 100 μmol/L HCY (p<0.05 and p<0.01, respectively). In conclusion, HCY can increase the expression of IL‐6 and mPGES, while PPAR‐γ activator can inhibit the increase of IL‐6 and mPGES induced by HCY.
Biochemical and imaging alterations of renal bone disease in newly detected predialysis and on maintenance dialysis patients
Authors: Mokarram Hossain Rana , Masud Iqbal Md , Enamul Hoque Md , Habibur Rahman Md , Ur Rashid Harun
Published: October 2005

Skeletal involvement in chronic kidney disease manifests long before the initiation of dialysis. This study aimed at identifying the extent of renal bone disease among predialysis and on maintenance dialysis patients. Thirty‐two patients (Group 1) on maintenance hemodialysis (MHD) for a variable period of time were compared with 20 newly detected irregularly treated advanced renal failure (immediately predialysis), patients (Group 2) for their clinical, biochemical and imaging features. The mean age of Group 1 and Group 2 patients was 45±14 vs. 34±15 years (p<0.05). Comparison of blood biochemistries between Groups 1 and 2 showed serum creatinine 9.9±2.9 vs. 13.4±4.4 mg/dL (p<0.01); calcium 10.1±1.8 vs. 7.8±1.2 mg/dL (p<0.001); phosphate 4.4±1.2 vs. 7.9±2.1 mg/dL (p<0.001); alkaline phosphatase 116.4±31.7 vs. 85.7±30.6 IU/L (p<0.05); and parathormone 71.7±48.2 vs. 146.9±92.1 pg/mL (p<0.05). Radiological changes present in the 2 groups were as follows: osteopenia 63% vs. 65% (ns); trabecular resorption 53% vs. 20% (p<0.05); soft tissue calcification 31% vs. 10% (p<0.05); bone cysts 16% vs. 26% (ns); and subperiosteal bone resorption 16% vs. 20% (ns). Technetium 99 methylene diphosphonate (Tc‐99 MDP) bone scans in both groups of patients showed similar increased uptake in wrist joint, tibia–fibula, costochondral junction, vertebral column, sternum, radius–ulna and mandible. X‐ray findings were positive for bone involvement in 59% of cases, and Tc‐99 scan was positive in 80% (p<0.05). It is concluded that newly detected, irregularly treated patients with advanced renal failure who are predialysis may present with deranged calcium homeostasis and a high prevalence of bone involvement similar to MHD patients.
Immunomodulating effects of vitamin D analogs in hemodialysis patients
Authors: Seibert Eric , Levin Nathan W , Kuhlmann Martin K
Published: October 2005

Apart from its well‐known functions in calcium homeostasis and parathyroid hormone regulation, 1,25‐(OH)2D3 and its synthetic analogs are being increasingly recognized for their potent antiproliferative, pro‐differentiative and immunomodulating activities. The effects of these drugs are exerted either via vitamin D receptor‐dependent genomic, or cell‐surface receptor‐mediated, non‐genomic pathways. Several vitamin D analogs with fewer hypercalcemic side effects have been developed for use in secondary hyperparathyroidism. These analogs may potentially improve treatment of autoimmune disorders and graft rejection, and in dialysis patients may open a new opportunity for amelioration of the chronic inflammatory status. It has recently been shown that hemodialysis (HD) patients treated with paricalcitol have lower total and cardiovascular mortality and morbidity rates and experience improved hospitalization outcomes compared with HD patients treated with calcitriol, suggesting a potential beneficial effect in chronic inflammation and the development of cardiovascular disease. Specific studies on the immunomodulating effects of vitamin D are needed in the HD population.
Impacts of prices and transactions costs on input usage in a liberalizing economy: evidence from Tanzanian coffee growers
Authors: Winter‐Nelson Alex , Temu Anna
Published: October 2005

Despite improvements in production incentives, agricultural output in Africa remained sluggish through the 1990s. Low use of purchased inputs may be part of the cause of persistently low productivity in African agriculture. This article analyzes the roles of relative prices and transactions costs in explaining low use of chemical inputs among Tanzanian coffee growers. A sample selection model indicates that output prices exert great influence on input purchases and that both fixed and variable transactions costs affect input use decisions. Travel costs in input and output markets have distinct effects on input usage, implying distinct avenues for interventions to promote more intensive use of agricultural inputs.
Modeling weekly Canary tomato exports
Authors: Rodríguez Gloria Martín , Hernández José Juan Cáceres
Published: October 2005

The European tomato market is characterized by a constant process of dynamic adjustment towards equilibrium. Furthermore, Canary Island tomato exports cause a high seasonal impact on market prices in the winter period. In these circumstances, an adequate distribution of weekly shipments throughout the year could contribute to maximize producers' profits. Moreover, Canary export levels show some degree of instability, clearly related to the changes in the EU trade rules and there is a long period, in the summer, without exports. The aim of this article is to analyze the long‐term movements and, particularly, the seasonal pattern of Canary Island tomato exports throughout the last two decades. To observe more clearly the exporter's decisions, weekly data have been used. The instabilities in the long‐term behavior of the series and the specific nature of the seasonal pattern should be taken into account, to capture the performance of exports accurately. Thus, this analysis is carried out using the structural approach to time series analysis, and the usefulness of spline functions as a tool capable of modeling seasonal variations for which the period does not remain the same over time is shown.
Hired labor use decisions in cassava‐producing households of sub‐Saharan Africa
Authors: Enete Anselm A. , Nweke Felix I. , Tollens Eric
Published: October 2005

Sub‐Saharan Africa is the only developing region of the world where agricultural output has been trailing population growth for most of the last three decades. Farming systems in the region are inherently risky because they are fundamentally dependent on the vagaries of weather. In addition, it is a region of crises; poverty, civil strife, and HIV/AIDS. Attention must therefore be focused on improving the production of crops that could thrive under these circumstances. Because of its tolerance of extreme drought and low input use conditions, cassava is perhaps the best candidate in this regard. And cassava is a basic food staple and a major source of farm income for the people of the region. The use of hired labor is important for its production growth because cassava root yield responds positively to the application of hired labor. This article, based on farm‐level information collected from six major cassava‐producing countries of Africa, within the framework of the Collaborative Study of Cassava in Africa, identifies strategic variables affecting the hired labor use decisions of producing households. The characteristics of the household head (age and number of years of formal education), the size of the household farm, good market access, and population pressure are found to motivate households to apply hired labor in cassava production. These observations underscore the need for investing in people—education—and in infrastructure—market access—as possible tools for improving food production in the region. The positive effect of farm size also suggests that some kind of land reform, which would put more farmland at the disposal of farm households, could be favorable to improving cassava production.
Effects of subsidies in Russian dairy farming
Authors: Bezlepkina Irina V. , Lansink Alfons G. J. M. Oude , Oskam Arie J.
Published: October 2005

This study develops a microeconometric model of specialized dairy farms in the Moscow region using panel data over the period 1995–2001. The model is used to analyze the role of subsidies on profit as well as input and output allocation. Theoretical conditions for short‐term profit maximization are not rejected by the data. Differences between farms allow for a fixed‐effect specification. The dairy producers in the region demonstrate a low responsiveness to market signals, but technology change becomes important. Labor, land, and livestock had low shadow prices. Although subsidies have a distorting effect on the input–output mix, this study shows they relieve the credit constraints on dairy farms and have an important positive influence on farm profit.
How much of commodity price behavior can a rational expectations storage model explain?
Authors: Peterson Hikaru Hanawa , Tomek William G.
Published: October 2005

A rational expectations competitive storage model was applied to the U.S. corn market, to assess the aptness of this framework in explaining monthly price behavior in an actual commodity market. Relative to previous models, extensive realism was added to the model, in terms of how production activities and storage costs are specified. By modeling convenience yield, “backwardation” in prices between crop years did not depend on the unrealistic assumption of zero ending stocks. Our model generated cash prices that were distributed with positive skewness and kurtosis, and mean and variance that increased over the storage season, comparable to the persistence and the occasional spikes observed in commodity prices. Futures prices were generated as conditional expectations of cash prices at contract maturity, and the variances of futures prices exhibited realistic time–to‐maturity and seasonal patterns. Model realizations of cash and futures prices over many “years” were used to demonstrate the wide variety of price behaviors that could be observed in an efficient market with a similar market structure, implying that economic and policy implications drawn from short, historical samples of prices could be misleading.
Lomé to Cotonou conventions: trade policy alternatives for the Senegalese groundnut sector
Authors: Bergtold Jason , Norton George , Brewster Charlene
Published: October 2005

The signing of the Cotonou Convention in June 2000 established a new trading relationship between the European Union and African, Caribbean, and Pacific States. Negotiations to establish new trading arrangements have already commenced and will lead to the establishment of economic partnership agreements or other viable alternatives. In this study, the economic impact on the Senegalese groundnut sector is assessed for the case in which Senegal enters into an economic partnership agreement with the European Union, or into an enhanced form of the Generalized System of Preferences. The preferred choice depends on whether Senegal's economic status classifies it as a least developed country (LDC) or not, as well as on other external trading arrangements. Findings indicate that as a non‐LDC, the best option for Senegal would be to enter into an economic partnership agreement. As a LDC, the best option would be to move to the enhanced generalized system of preferences, thereby allowing Senegal to retain Lomé‐style trade preferences. Furthermore, increased development funding under the Cotonou Convention could help shield the Senegalese groundnut sector from adverse economic impacts arising from either trading option.
Effects of management information from FADN on profitability of Dutch potted‐plant firms
Authors: Csajbok Ildiko , Oude Lansink Alfons , Huirne Ruud
Published: October 2005

The Dutch Farm Accountancy Data Network (FADN) provides managerial reports to participants of the network. This article analyzes the impact of this type of management information on the profitability of agricultural producers. A dual system of input demand and output supply equations is applied to measure the effect of management information. The approach is applied to a panel data set of Dutch potted‐plant firms over the period of 1975–1995. Management information provided by the FADN resulted in savings in materials and services and a more intensive use of energy. Shadow prices of structure, machinery, and labor increased as a result of management information. The results show that management information is more likely to have a positive effect on profitability of potted‐plant firms in the long run than in the short run. The results suggest that the availability of management information allows firms to operate on a larger scale in the long run.
Competition between farmed and wild salmon: the Japanese salmon market
Authors: Asche Frank , Guttormsen Atle G. , Sebulonsen Tom , Sissener Elin H.
Published: October 2005

This article examines the Japanese market for salmon. This market is of interest, since it is the largest and most diversified salmon market in the world with wild and farmed species, from Europe and South and North America, competing in the same market. In contrast to the European Union (EU)‐ and U.S.‐markets, there have been neither trade conflicts nor trade restrictions. The Japanese market can hence provide information about the impact of bringing substantial quantities of a new product into a market, and the effect of large‐scale aquaculture on traditional fisheries. In this article, market integration between wild and farmed salmon on the Japanese market is examined, using both bivariate and multivariate cointegration analysis. Tests for the Law of One Price are also conducted. The results indicate that the species are close substitutes on the market, and that the expansion of farmed salmon has resulted in price decreases for all salmon species.
Moving up the processing ladder in primary product exports: Sri Lanka's “value‐added” tea industry
Authors: Ganewatta Gaminda , Waschik Robert , Jayasuriya Sisira , Edwards Geoff
Published: October 2005

Governments in many developing countries, influenced by the experience of the East Asian newly industrialized countries, have adopted policies to enhance domestic processing of primary commodities as a tool for accelerating employment growth, export revenues, and development. Sri Lanka has traditionally exported tea in the form of bulk (commodity) teas, but “value‐added” teas such as packaged teas, tea bags, etc., have expanded in recent years. This article examines factors affecting the processing of value‐added tea products in Sri Lanka by modeling export supply behavior. Estimates of the long‐run relationship and short‐run dynamics of export supply are presented and discussed. The price of value‐added tea relative to bulk tea, and industry capacity, are identified as the main determinants of export supply, while exchange rate changes have no discernible effect. The policy implications of the analysis for enhancing further expansion of such value‐added teas are presented. These are of interest for both policy makers and development analysts. In particular, the reasons that undermine the effectiveness of exchange rate policy as an instrument to stimulate value addition of primary products have much relevance for similar developing countries.
Are apparent associations between parental representations and psychosis risk mediated by early trauma?
Authors: Janssen I. , Krabbendam L. , Hanssen M. , Bak M. , Vollebergh W. , De Graaf R. , Van Os J.
Published: October 2005

Objective:  It was investigated whether the reported association between representations of parental rearing style and psychosis does not represent a main effect, but instead is a proxy indicator of the true underlying risk factor of early trauma.

Method:  In a general population sample of 4045 individuals aged 18–64 years, first ever onset of positive psychotic symptoms at 3‐year follow‐up was assessed using the Composite International Diagnostic Interview and clinical interviews if indicated. Representations of parental rearing style were measured with the Parental Bonding Instrument (PBI).

Results:  Lower baseline level of PBI parental care predicted onset of psychotic symptoms 2 years later. However, when trauma was included in the equation, a strong main effect of trauma emerged at the expense of the effect size of PBI low care.

Conclusion:  The results suggest that associations between representations of parental rearing style and psychosis may be an indicator of the effect of earlier exposure to childhood trauma.
Family history of suicide, female sex, and childhood trauma: separate or interacting risk factors for attempts at suicide?
Authors: Roy A. , Janal M.
Published: October 2005

Objective:  Female sex, childhood trauma, and a family history of suicidal behavior are three well established risk factors for attempting suicide. However, interactions between these three factors in attempting suicide have been little studied.

Method:  One thousand eight hundred and eighty‐nine abstinent substance dependent patients were interviewed about their lifetime and family history of suicidal behavior and completed the Childhood Trauma Questionnaire (CTQ). Gender, family history of suicidal behavior, and CTQ scores – and their interaction – were examined in relation to suicidal behavior.

Results:  Each of the three risk factors was associated with at least a doubling of the risk for an attempt at suicide. There were no significant interactions in relation to the risk of making an attempt. However, female sex and higher levels of childhood trauma each discriminated patients at risk for both a younger age of first attempting suicide and for making more attempts.

Conclusion:  Female sex, childhood trauma, and a family history of suicidal behavior are each independent, and non‐interacting, risk factors for attempting suicide. Additionally, female sex and high childhood trauma are independent risk factors for both an early onset of first attempting suicide and for making more attempts.
Phene Plate (PhP) biochemical fingerprinting
Authors: SAEEDI B. , TÄRNBERG M. , GILL H. , HÄLLGREN A. , JONASSON J. , NILSSON L. E. , ISAKSSON B. , KÜHN I. , HANBERGER H.
Published: October 2005

Pulsed‐field gel electrophoresis (PFGE) is currently considered the gold standard for genotyping of enterococci. However, PFGE is both expensive and time‐consuming. The purpose of this study was to investigate whether the PhP system can be used as a reliable clinical screening method for detection of genetically related isolates of enterococci. If so, it should be possible to minimize the number of isolates subjected to PFGE typing, which would save time and money. Ninety‐nine clinical enterococcal isolates were analysed by PhP (similarity levels 0.90–0.975) and PFGE (similarity levels ≤3 and ≤6 bands) and all possible pairs of isolates were cross‐classified as matched or mismatched. We found that the probability that a pair of isolates (A and B) belonging to the same type according to PhP also belong to the same cluster according to PFGE, i.e. p(APFGE=BPFGE • APhP=BPhP), and the probability that a pair of isolates of different types according to PhP also belong to different clusters according to PFGE, i.e. p(APFGE≠BPFGE • APhP≠BPhP), was relatively high for E. faecalis (0.86 and 0.96, respectively), but was lower for E. faecium (0.51 and 0.77, respectively). The concordance which shows the probability that PhP and PFGE agree on match or mismatch was 86%–93% for E. faecalis and 54%–66% for E. faecium, which indicates that the PhP method may be useful for epidemiological typing of E. faecalis in the current settings but not for E. faecium.
Cell‐type‐specific expression of p53 and p21 in giant cell arteritis
Authors: NORDBORG C. , ÅMAN P. , PERSSON M. , NORDBORG E.
Published: October 2005

The aim of the present study was to investigate the expression of TP53 (p53) and CDKN1A (CIP1; p21) in the arterial wall in giant cell arteritis (GCA). Cross‐sections from 18 temporal artery biopsies displaying GCA and 8 control arteries were double‐stained with monoclonal antibody directed at p53 or p21 on the one hand and alpha‐smooth muscle actin, CD68 (macrophage) or CD3 (T‐cell) on the other. Nuclear p53 was expressed in CD68‐positive cells and smooth muscle cells in 16 of the 18 inflamed arteries. P21‐positive nuclei were found in CD68‐positive cells in 14 biopsies and in smooth muscle cells in all the specimens. All p53‐positive giant cells also contained p21‐positive nuclei. In the giant cells, immunopositive nuclei were mixed with negative ones. CD3‐positive T‐cells did not express p53 or p21. Only one p53‐positive smooth muscle cell nucleus was found in the non‐GCA controls and, compared with GCA, p21 expression was noted in few smooth muscle nuclei. The presence of p53 and p21 in the same types of cell in GCA indicates that the former protein is functional; p21 expression is induced by wild‐type, functional p53 but not by its mutant form. The current observations suggest cellular stress in GCA, the nature of which requires further investigation.
Verruciform xanthoma of the oral cavity: clinicopathological study relating to pathogenesis
Authors: HU JI‐AN , LI YINING , LI SONGYING
Published: October 2005

Verruciform xanthoma is a rare condition that was first reported in the oral cavity in 1971. Its histopathology is distinctive on account of the presence of foamy histiocytes within elongated dermal papillae. Three cases of oral mucosal verruciform xanthoma were studied. Immunohistochemical staining by streptavidin‐peroxidase and in situ hybridization to detect human papillomavirus (HPV types 6, 11, 16, 18) DNA and matrix metalloproteinase (MMP‐2, ‐9) RNA were performed to investigate the pathogenesis of verruciform xanthoma. This study showed that the foam cells were strongly positive for CD68 (KP1) and vimentin. Cytokeratin, PCNA and S‐100 stained focally negative in foam cells. In situ hybridization failed to detect HPV (types 6, 11, 16, 18) in any of the three cases. Based on our findings we conclude that verruciform xanthoma is most likely not a human papillomavirus‐associated lesion; the foam cells, as a histological hallmark of the lesion, are most likely derived from the monocyte‐macrophage lineage, and verruciform xanthoma is, at least partly, mediated by an immune mechanism. MMPs degrade basilar membrane that promotes the reciprocal induction between epithelium and mesenchyme. However, as yet unrecognized factors may play a role in the development of epithelium‐mesenchyme reciprocal induction.