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T D Tjan

Publications and source records attributed to T D Tjan.

23 records · Page 2Linked to original sources
PubMed1998

Transplant vasculopathy.

Transplant vasculopathy constitutes the major impediment to long-term survival in heart transplant recipients. Within the "response to immune injury" paradigm, it can best be understood as the resultant of an orchestrated recipient immune response to the initial allogenic stimulus by graft vascular endothelium. This response incorporates the elaboration of complex coordinated cytokine patterns and corresponding cell types including B-lymphocytes, T-helper1- and T-helper2-cells, cytotoxic T-cells, macrophages, and polymorphonuclear cells. These attack the alloantigenic vascular endothelium and lead, by complex cytokine signaling, to migration of donor smooth muscle cells from the media into the intima, associated with a switch from the contractile to a synthetic phenotype. In conjunction with recipient T-cells, macrophages, and lipids, the intimal fibroproliferative growth of the donor vessel is hereby initiated.

Animals↗
PubMed1998

Left-ventricular expression of interleukin-6 messenger-RNA higher in idiopathic dilated than in ischemic cardiomyopathy.

During end-stage heart failure, plasma levels of interleukin-6 (IL6) are elevated. This cytokine exerts a negative inotropic influence on the myocardium. The production site of IL6 is unclear. We examined the hypothesis that IL6 in end-stage heart-failure patients is produced in the myocardium itself and is differentially regulated according to etiology. Cardiac tissue was obtained from 27 patients (idiopathic dilated cardiomyopathy, (DCM) 9/6 m/f, age 46 +/- 14 y; ischemic cardiomyopathy (ICM), 11/1 m/f, age 55 +/- 8 y) at the time of transplantation. The tissue was subjected to IL6 Northern-blot analysis. Signals were quantified by densitometric scanning after normalization to G3 PDH mRNA. Data were compared by Mann-Whitney test between DCM and ICM patients, divided by chamber origin. IL6 transcripts were found in all patients. In DCM, left-ventricular IL6 mRNA expression was higher than in ICM (p = 0.006). Median right-ventricular as well as left- and right-atrial IL6 mRNA expression was not significantly different in both groups. In summary, in end-stage heart failure, IL6 mRNA is consistently expressed in the myocardium. Left-ventricular expression is higher in DCM than in ICM. These data support the concept of a potentially reversible inflammatory component in the etiology of DCM which is more pronounced than in patients with ICM of comparable clinical severity.

Adult↗
PubMed1994

Reconstructive vascular surgery in rotationplasty for malignant tumors of the femur.

The rotationplasty procedure of the femur, as first described by Borrgreve, is the functional improvement of an abnormally shortened lower limb. In the last 15 years this procedure has been used in its original form and as modification for tumors of the femur and proximal tibia. The reconstruction of the femoral vessels as an important part of the operation has not enough been accentuated. Principally two types of reconstructions can be performed: the vessels are dissected in the adductor canal or a segmental resection and reanastomosis are performed. Between January 1990 and April 1993 classical and modified rotationplasties were performed for malignant tumors in 34 patients in our institution. In all cases a segmental femoral vessel resection with end-to-end anastomosis were performed. No intra- and postoperative vascular related complications occurred. The authors emphasize the advantage of this method: reanastomosing resected femoral vessels by experienced vascular surgeons is a save, time-saving method. In addition, the radicality of the operation increases in order to obtain excellent long term results.

Adolescent↗
PubMedDate not supplied

Successful perioperative management of congenital cystic adenomatoid malformation of the lung by high frequency oscillatory ventilation--report of two cases.

BACKGROUND: Comparable to congenital diaphragmatic hernia, patients with congenital cystic adenomatoid malformation of the lung (CCAM) may develop life-threatening mediastinal shift and persistent pulmonary hypertension. In patients with diaphragmatic hernia, high frequency oscillatory ventilation (HFOV) has been shown to allow perioperative stabilisation. PATIENTS: One term and one premature newborn of 30 gestational weeks with CCAM. Both patients developed massive mediastinal shift and intermittend pulmonary hypertension. METHOD: Retrospective chart review. RESULTS: In both patients perioperative stabilisation could be achieved by institution of HFOV. This allowed safe operation in the almost immobile surgical site and controlled transient episodes of pulmonary hypertension. The resection of the malformed lobe was performed under continued HFOV on the neonatal intensive care unit. Hereby, transport stress and additional hyperinflation by hand ventilation could be avoided. CONCLUSION: Comparable with the situation when repairing a congenital diaphragmatic hernia, perioperative HFOV may be advantageous in managing severe CCAM.

Cystic Adenomatoid Malformation of Lung, Congenita↗