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J B Chen

Publications and source records attributed to J B Chen.

At least 19 recordsLinked to original sources
PubMed2007

BMP-7 and CBFA1 in allograft bone in vivo bone formation and the influence of gamma-irradiation.

An initial study showed that morselized human bone grafts were osteoconductive and osteoinductive when implanted in nude rat tibial window defects, and 25 kGy of gamma-irradiation significantly reduced those properties. The mechanism of the osteoinductivity and the influence of gamma-irradiation required further investigation. In this study we assessed the paraffin sections of seven morselized human bone grafts implanted into rat tibial defects for 3 weeks after being treated with 0, 15, or 25 kGy gamma-radiation respectively. Osteoclast-like cell counting and protein expressions of bone morphogenetic protein-7 (BMP-7), core binding factor alpha1 (CBFA1), and proliferating cell nuclear antigen (PCNA) were investigated and the positive signals were quantitatively analyzed. More new bone formation was observed in the 0 and 15 kGy groups compared with 25 kGy groups. The newly formed bones were found mainly from the intact cortex into the defects bridged by the implanted grafts. A dense staining of BMP-7 and CBFA1 was noted in the osteoblast-like cells in those areas. The BMP-7 and CBFA1 staining was also seen in the cells surrounding the implanted grafts in the centre areas of the defects in distance from the intact cortex. Quantitative analysis of immunohistochemical staining of the centre areas of the defects showed that gamma-irradiation (15 and 25 kGy) significantly reduced the expression of CBFA1 and BMP-7. In conclusion, morselized human bone grafts may contain some factors, which induced osteoblast lineage differentiation and bone formation and gamma-irradiation damages those bone inducing factors.

Animals↗
PubMed2006

Troponin T measurement can predict persistent left ventricular dysfunction in peripartum cardiomyopathy.

OBJECTIVE: To determine whether measurement of cardiac troponin T (cTnT) concentration in newly diagnosed peripartum cardiomyopathy (PPCM) can be used to predict persistent left ventricular dysfunction after a 6-month follow-up. PATIENTS AND METHODS: This was a prospective, multiple-centre clinical trial that studied 106 patients with newly diagnosed PPCM surviving over 6 months. cTnT concentration was measured within 2 weeks of the onset of PPCM. RESULTS: Serum cTnT concentration was negatively correlated with left ventricular ejection fraction (LVEF) at follow-up (LVEF, r = -0.518, p = 0.0001). Analysis by receiver operator characteristic curve yielded an area under the curve of 0.764 (95% CI 0.669 to 0.860, p = 0.0001, vs null hypothesis value 0.5) for cTnT, and a cTnT concentration cut off of >0.04 ng/ml, predicting persistent left ventricular dysfunction with a sensitivity of 54.9% and a specificity of 90.9%. Among 106 recruited patients, there were 33 patients with cTnT concentrations >0.04 ng/ml and 73 patients with cTnT concentrations < or =0.04 ng/ml. After a 6-month follow-up, there was significantly smaller LVEF (35.42% (13.04% vs 50.16% (10.48%, p = 0.0001) and more persistent left ventricular dysfunction (84.8% vs 31.5%, OR = 12.17 (95% CI 4.17 to 35.57), p = 0.001) in patients with cTnT >0.04 ng/ml than in patients with cTnT < or =0.04 ng/ml. CONCLUSION: Serum cTnT concentration measured within 2 weeks of the onset of PPCM was correlated negatively with LVEF at follow-up. This marker offers a simple, quick, inexpensive, non-invasive method for predicting a persistent LVEF of < or =50%. A cTnT concentration of >0.04 ng/ml predicted persistent left ventricular dysfunction with a sensitivity of 54.9% and a specificity of 90.9%.

Adult↗
PubMed2006

Successful outpatient treatment of renal vein thrombosis by low-molecular weight heparins in 3 patients with nephrotic syndrome.

Renal vein thrombosis (RV Thromb) is a serious complication ofnephrotic syndrome. Anticoagulation is usually recommended as the treatment of choice. This study reports 3 nephrotic patients diagnosed to have RVThromb combined with thromboembolic events. Low-molecular weight heparin (LMWHep) was given subcutaneously every 12 hours following the diagnosis of RVTromb, which continued at the outpatient clinic after an average of 11 in-hospital days. The patients visited the nephrology outpatient clinic every other week and underwent magnetic resonance image (MRI) studies at 6-week intervals for follow-up of patency of the involved renal vein. LMWHep was discontinued when MRI showed this patency. The average outpatient treatment period was 74 days. There was no recurrent RVThromb in the follow-up course of 6 months after discontinuation of LMWHep. Kidney function was preserved, as indicated by image studies and serial renal function tests. LMWHep produced a more predictable anti-coagulant effect, a superior bioavailability, a longer half-life and a dose-independent effect than unfractionated heparin and coumadin. These benefits made the outpatient treatment of RVThromb possible. Our report recommends outpatient treatment of RVThromb by LMWHep because it is feasible, effective and safe.

Adult↗
PubMed2005

Comparison of rate control and rhythm control in patients with atrial fibrillation after percutaneous mitral balloon valvotomy: a randomised controlled study.

OBJECTIVE: To compare rate control and rhythm control strategies in patients with atrial fibrillation (AF) after percutaneous mitral balloon valvotomy (PMV). METHODS: 183 patients with AF after successful PMV, with AF duration <or= 12 months and post-PMV left atrial (LA) size <or= 45 mm, were studied in a prospective, randomised trial. The primary end point was improvement in AF-related symptoms. Secondary study end points were 6 min walk tests, quality of life (QOL), normalisation of LA size, number of hospital admissions and duration of hospital stay. RESULTS: Over one year, 2% patients in the rate control group had sinus rhythm, as compared with 96% of patients in the rhythm control group (p < 0.001). A greater proportion of patients reported improvement in symptoms in the rhythm control group than in the rate control group (p < 0.0001 at every visit time). Walking distance in a 6 min walk test, QOL and LA size normalisation were better in the rhythm control group than in the rate control group. The strategy of rhythm control was associated with similar numbers of hospital admissions but with longer duration of hospital admissions. Drug-related side effect did not differ between the rate control and rhythm control groups. During the follow-up period, no patients in either group had embolic or transitory ischaemic neurological events. CONCLUSIONS: In patients with AF after PMV, AF duration <or= 12 months and post-PMV LA size <or= 45 mm, sinus rhythm was easy and safe to achieve and maintain. Moreover, patients benefited from restoration and maintenance of sinus rhythm in terms of improved AF-related symptoms, 6 min walk tests and QOL, and of LA size normalisation. Rhythm control should therefore be considered as the preferred initial therapy for this group of patients. The optimal strategy to treat AF after PMV should be individualised.

Adult↗
PubMed2005

Incidental primary hyperparathyroidism in a hypercalcaemic woman with tuberculous peritonitis.

We report on a 51-year-old woman with initial hypercalcaemia and unknown ascites. In spite of unyielding laparoscopy, laparotomy showed findings compatible with tuberculous peritonitis (TBP). Unexpectedly, a series of examinations eventually revealed the concurrence of hyperparathyroidism due to a parathyroid adenoma. Anti-tuberculous regimen was given and was uneventful. However, hypercalcaemia was not decreased but sustained at a high level even after anti-tuberculous therapy for 3 months. Parathyroidectomy was performed with subsequent normalisation of hypercalcaemia. The aetiology of hypercalcaemia in a patient with an explored disease able to cause this electrolyte abnormality such as TBP may be a coexistent occult parathyroid adenoma.

Adenoma↗
PubMed2005

Recombinant human erythropoietin independence in chronic hemodialysis patients: clinical features, iron homeostasis and erythropoiesis.

AIMS: Recombinant human erythropoietin (r-HuEPO) is widely used to correct renal anemia in uremic patients. Interestingly, some chronic hemodialysis (HD) patients can maintain high hemoglobin level without the need of r-HuEPO. The aim of this study is to investigate clinical features, iron metabolism and erythropoiesis of these r-HuEPO-independent HD patients. METHODS: r-HuEPO independence was defined in dialysis patients as hemoglobin greater than 12 g/dl and no use of r-HuEPO for at least 6 months. An age- and sex-matched group was selected for comparison. Their underlying diseases, duration of hemodialysis therapy, efficacy of dialysis (Kt/V), normalized protein catabolic rate (nPCR) and body mass index (BMI) were recorded. Laboratory data including: hemoglobin, albumin, high sensitivity C-reactive protein, serum iron, total iron binding capacity, transferrin saturation, ferritin, intact parathyroid hormone, soluble transferrin receptor (sTfR), serum EPO, cortisol, testosterone, aluminum and leptin levels were measured. Renal sonography was also performed in each patient to evaluate renal cyst formation. RESULTS: About 2.3% of all HD patients (21/888; M : F = 18 : 3) were r-HuEPO-independent. These patients had significantly longer HD duration and higher serum EPO and sTfR levels, and lower transferrin saturation rate than dependent groups. Correlation analysis revealed that hemoglobin level strongly correlated with HD duration, serum sTfR and EPO levels. Levels of sTfR were positively related with serum EPO levels and BMI. Multivariate regression analysis showed that level of sTfR was the only independent factor related to r-HuEPO independence. CONCLUSION: R-HuEPO independence is rare among chronic hemodialysis patients. Factors contributing to this dependence are complex and multiple. Level of serum sTfR parallels erythropoiesis and is the most significant factor associated with r-HuEPO independence in chronic HD patients.

Adult↗
PubMed2005

Lanthanum carbonate (Fosrenol) efficacy and tolerability in the treatment of hyperphosphatemic patients with end-stage renal disease.

AIMS: High serum phosphorus levels are a common problem in patients receiving long-term dialysis treatment. Lanthanum carbonate (Fosrenol) is a new non-aluminum, non-calcium phosphate binder developed for the treatment of hyperphosphatemia in patients with end-stage renal disease (ESRD). We report data from a recent trial, which, for the first time, assessed the efficacy and tolerability of lanthanum carbonate treatment, compared with placebo, in Chinese patients with ESRD. PATIENTS AND METHODS: Following a one- to three-week washout phase and a four-week, open-label lanthanum carbonate dose-titration phase, male and female hemodialysis patients were randomized (1:1) to receive either lanthanum carbonate or placebo for four weeks. The primary efficacy parameter of the study was the control of serum phosphorus levels (< or =1.8 mmol/l [< or = 5.6 mg/dl]). Secondary endpoints included the profile of serum phosphorus during titration and parathyroid hormone, calcium, and calcium x phosphorus (Ca x P) product levels. The safety and tolerability of lanthanum carbonate were assessed by monitoring adverse events throughout the study. RESULTS: Mean serum phosphorus level at the end of washout was 2.5 +/- 0.5 mmol/l (7.7 +/- 1.5 mg/dl; n=73), and there was no evidence of a difference in levels between the treatment groups pre-randomization. At the end of the study, lanthanum carbonate-treated patients had significantly lower phosphorus levels (1.6 +/- 0.5 mmol/l [5.1 +/- 1.5 mg/dl]; n=30) than those receiving placebo (2.3 +/- 0.4 mmol/l [7.2 +/- 1.3 mg/dl]; n=31; p < 0.001). In addition, a significantly higher proportion of patients receiving lanthanum carbonate had controlled serum phosphorus levels (60%) compared with the placebo group (10%; p < 0.001). Ca x P product levels were also significantly lower in the lanthanum carbonate group at the end of randomized treatment (p < 0.001). Lanthanum carbonate was well tolerated; only one serious adverse event was reported, which was unrelated to treatment. CONCLUSIONS: Lanthanum carbonate was shown to be an effective and well-tolerated phosphate binder for the treatment of hyperphosphatemia in Chinese patients with ESRD. This finding supports the results of previous US and European studies, which have also shown that lanthanum carbonate treatment effectively controls serum phosphorus levels.

Adult↗
PubMed2004

Hypercalcaemia and haemophagocytic syndrome: rare concurrent presentations of disseminated tuberculosis in a dialysis patient.

Tuberculosis remains an important cause of infection in chronic haemodialysis patients. Frequent extrapulmonary involvement, non-specific presentation and limited diagnostic tools usually make early diagnosis difficult. Herein, we report on an 83-year-old female patient who had been on regular heamodialysis therapy for 15 years, who presented with asymptomatic hypercalcaemia and pancytopenia. Haemophagocytic syndrome was documented during the admission period. Mycobacterium tuberculosis was cultured from bone marrow 1 month after her demise. This case report highlights the non-specific manifestations of extrapulmonary tuberculosis in dialysis patients and the limited value of conventional diagnostic methods. We would like to recommend aggressive intervention and early tissue aspiration from possible infectious sites when tuberculosis cannot be completely ruled out. Disseminated tuberculosis should be considered as an indication of hypercalcaemia where haemophagocytic syndrome occurs simultaneously.

Aged↗
PubMed2004

Successful treatment of crescentic glomerulonephritis associated with adult-onset Henoch-Schoenlein purpura by double-filtration plasmapheresis.

Henoch-Schoenlein purpura (HSP) crescentic glomerulonephritis with acute renal failure in adults is extremely rare. The condition carries a grave renal outcome if it is not appropriately managed. Oral corticosteroids, intravenous methylprednisolone pulse therapy and plasmapheresis with concomitant plasma replacement have been used alone or in various combinations to treat patients with HSP nephritis, yet the effects are uncertain. We describe a 33-year-old man with oliguric acute renal failure in the setting of HSP crescentic glomerulonephritis that is refractory to intravenous methylprednisolone pulse therapy (1,000 mg/day for 3 days) with maintained oral prednisolone (1 mg/kg/day) and oral cyclophosphamide (2 mg/kg/day) for 3 weeks, resulting in successful recovery of renal function after 9 sessions of simple double-filtration plasmapheresis treatment without concomitant plasma replacement. There was no recurrence of vasculitic events within 18 months. In this case, we emphasize that simple double-filtration plasmapheresis without concomitant plasma replacement is an effective and safe modality therapy for adult patients with HSP crescentic glomerulonephritis and acute renal failure, especially when conventional therapy has failed.

Acute Kidney Injury↗
PubMed2004

Thermal drying of wastewater sludge with crack formation.

We examined in this work the drying characteristics of wastewater sludge. The drying flux of the constant-rate period for sludge cake could be up to 40% higher than that from a sand bed. Owing to the considerable volume shrinkage of cake, cracks would form and develop on the crack surface, which yielded three-dimensional but rather than the one-dimensional cake structure assumed in conventional drying theories. The crack length was fully developed in the first 30 min of drying, while the width of crack increased linearly with time. Using these data the drying flux from the cracks was estimated. Enhanced drying flux was noticeable which depended on the crack shape and the crossflow velocity.

China↗
PubMed2003

Tuberculous peritonitis in uremic patients.

AIMS: To identify clinical features and treatment response of tuberculous peritonitis (TBP) in a uremic population, a retrospective case-control study was performed. MATERIALS AND METHODS: Thirteen uremic patients with TBP (Group I: 62.7 +/- 6.8 years, male 54%) collected between January 1986 and January 2002 were compared with another two age- and sex-matched controls: 19 non-azotemic patients with TBP (Group II: 62.9 +/- 7.3 years, male 47%) and 30 uremic patients without TBP (Group III: 61.1 +/- 8.7 years, male 47%). Clinical information and data of ascites and blood examinations were evaluated. RESULTS: Significant differences between Groups I and II were found in comorbidity, hypertension, anorexia, percentages of neutrophil and lymphocyte from blood and ascites, and serum calcium (sCa), phosphorus and albumin-adjusted calcium (sAACa). However, no significant differences in duration of symptoms, coexistent pulmonary tuberculosis (p = 0.061), duration or complications of therapy and mortality (p = 0.13) were detected. Significant differences between Groups I and III were found in peripheral white cell counts and percentages of neutrophil and lymphocyte as well as in serum creatinine (sCr), albumin, sCa, sAACa and intact parathyroid hormone (iPTH). CONCLUSIONS: Non-specific symptoms make the diagnosis of TBP in a uremic population difficult. However, neutrophil predominance in blood and ascites, hypoalbuminemia, relatively lower sCr and hypercalcemia with suppressed serum iPTH were found to be characteristic. In TBP uremic patients, therapy complications were not common and there was a tendency for higher mortality, largely due to septic shock.

Aged↗
PubMed2002

Biomonitoring trace element atmospheric deposition using lichens in China.

Concentrations of 32 elements, Ag, As, Au, Ba, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb, and Zn were determined by instrumental neutron activation analysis (INAA) in the early preserved epiphytic lichens (Parmotrema recticulatum) from the remote southwestern China area in the 1960s, 1980s and 1990s. The concentrations of Ag, As, Ce, Cr, Cs, Eu, Fe, Hf, La, Nd, Ni, Sc, Se, Sm, Tb, U, Yb and Zn were dropped down by the temporal prolongation. The elemental concentration levels obtained from the organisms indicate that the extent of heavy metal atmospheric deposition among the sampling sites has been declining during the past decades.

China↗
PubMed2002

Nosocomial blood-stream infection in patients with end-stage renal disease: excess length of hospital stay, extra cost and attributable mortality.

Patients with end-stage renal disease undergoing haemodialysis are at high risk of nosocomial blood-stream infection (BSI), but data on the associated costs in this patient population are not available. Therefore, we conducted a retrospective matched (1:2) case-control study of such patients undergoing haemodialysis from January 1998 to December 1998 in a medical centre in southern Taiwan to determine the excess length of hospital stay, attributable mortality, and the extra cost caused by nosocomial BSI. The excess length of hospital stay was 30 days for cases vs. 16 days for controls (P<0.001), the mortality rate was 26.3% for cases vs. 0 for controls (P=0.003) (attributable mortality being 26.3%), and the median of overall costs was 131,584 dollars NT for cases vs. 65,282 dollars NT for controls (P<0.001). Based on these findings, we believe that an effective programme to minimize nosocomial BSI in this patient population would greatly reduce their medical and economic burdens.

Case-Control Studies↗
PubMed2001

Parathyroidectomy can improve bone mineral density in patients with symptomatic secondary hyperparathyroidism.

HYPOTHESIS: The recovery of osteoporosis or bone mineral density (BMD) after parathyroidectomy and autotransplantation can be improved in patients with symptomatic secondary hyperparathyroidism. DESIGN: Case series. SETTING: Tertiary referral center. PATIENTS: Forty-five patients with symptomatic secondary hyperparathyroidism who underwent total parathyroidectomy and autotransplantation were included. They were divided into an osteoporotic group (n = 20) and a nonosteoporotic group (n = 25) according to preoperative T scores less than -2.5 at either the lumbar spine (L1-L4) or the femoral neck (FN). INTERVENTIONS: Serum levels of calcium, phosphorus, alkaline phosphatase, and intact parathyroid hormone were checked before surgery and 1 day, 1 week, and 3 months after surgery. The BMDs of the FN and L1-L4 were measured using dual-energy x-ray absorptiometry before surgery and 6 months after surgery. RESULTS: Patients with osteoporosis were older (mean +/- SD, 50.2 +/- 14.0 years) than those without osteoporosis (42.7 +/- 9.1 years) (P =.04). Except for bone fractures found in 2 women in the osteoporotic group, there were no significant differences between the 2 groups in sex, clinical manifestations, duration of dialysis, weight of removed parathyroid tissue, and types of dialysis. Also, serum levels of calcium, phosphorus, alkaline phosphatase, and intact parathyroid hormone were similar in both groups. Both 1 day and 1 week after total parathyroidectomy and autotransplantation, serum levels of calcium and intact parathyroid hormone decreased rapidly and then gradually increased 3 months later; however, serum levels of alkaline phosphatase increased rapidly and then gradually decreased 3 months later. Six months after parathyroidectomy, BMD, T score, and Z score at L1-L4 and the FN increased significantly (P<.001). The increment was much better in the osteoporotic group than in the nonosteoporotic group (P<.001). Also, osteopenia or osteoporosis improved significantly after parathyroidectomy at both L1-L4 and the FN (P<.001 for both). CONCLUSION: Parathyroidectomy and autotransplantation can improve BMD of symptomatic secondary hyperparathyroidism at L1-L4 and the FN.

Absorptiometry, Photon↗
PubMed2001

Neglected bilateral femoral neck fractures in a patient with end-stage renal disease before chronic dialysis.

Bilateral femoral neck fractures are rarely reported in patients with end-stage renal disease before chronic dialysis. We report on a 39-year-old woman with neglected bilateral femoral neck fractures, who presented with severe uremic complications prior to chronic dialysis. Three years before admission, she had injured herself in a trivial slip with subsequent bilateral hip pain. She had progressively waddled since then. Pelvic X-ray taken after admission revealed bilateral femoral neck fractures. Bilateral hip hemiarthroplasties were subsequently performed. Displaced femoral neck fractures were found intraoperatively. Pathologic findings and results of examinations supported the coexistence of osteoporosis and high turnover renal osteodystrophy, rendering this woman at high risk of bilateral femoral neck fractures. Therefore, preventing a simple fall or trivial accident and treating renal osteodystrophy and osteoporosis are paramount in patients with chronic renal failure even before the start of dialysis therapy. We also emphasize the need to seek any possible underlying metabolic bone disease once a patient presents with unusual fractures.

Adult↗
PubMed2001

Surgical treatment for rectal prolapse.

BACKGROUND: The problem of full-thickness rectal prolapse is formidable, with no clear predominant treatment of choice. Several operations have been proposed to correct rectal prolapse which can be divided into transabdominal and perineal procedures. METHODS: From September 1982 to October 1999, 32 patients with rectal prolapse were treated with surgical procedures. There were 16 males and 16 females with a mean age of 58.3 years (Range 17-89). Forteen patients received rectopexy procedure, 6 patients received sigmoidectomy, 6 patients received perineal rectosigmoidectomy, 1 patient received Delorme procedure, 1 patient received Thiersch procedure and 4 patients received laparoscopic-assisted sigmoidectomy. The median follow up times were 7.5 years. RESULTS: In the rectopexy group, complication occurred in one patient (7.1%) and one patient recurred (7.1%). In the sigmoidectomy group, there were no complication but one patient recurred (10%). In the perineal rectosigmoidectomy group, there were no complication, but one patient recurred (16.7%). The total complication rate were 3.1% and total recurrence rate were 9.3%. CONCLUSIONS: Although, the best operation for rectal prolapse remains a controversial subject, we believe that laparoscopic-assisted sigmoidectomy offers a promising new option for the treatment of rectal prolapse.

Adolescent↗