Hemangiopericytoma of the Greater Omentum

A 41-year-old Chinese woman was admitted to our hospital with epigastric pain. Computed tomography detected a heterogeneous enhancement tumor fed by the left gastroepiploic artery in the left lower quadrant and cholelithiasis. Excision of the tumor in the greater omentum and cholecystectomy were performed laparoscopically. Histological findings confirmed a diagnosis of hemangiopericytoma with low-grade malignancy. To our knowledge, hemangiopericytoma of the greater omentum is very rare, and only 12 cases were reported in English literature. We report a case of hemangiopericytoma arising in the greater omentum and review the literature.     

Lack of modifying effects of atrazine and/or tamoxifen on thyroid carcinogenesis in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine (DHPN)

The modifying effects of atrazine, and/or tamoxifen, on thyroid carcinogenesis were investigated in a rat two-stage carcinogenesis model following N-bis(2-hydroxypropyl)nitrosamine (DHPN) initiation. Five-week-old male F344 rats were given a single subcutaneous injection of DHPN (2800 mg/kg, body weight) or vehicle alone. Starting 1 week later, the animals were fed a diet supplemented with 0, 5, 50 or 500 ppm of atrazine, 500 ppm atrazine plus 5 ppm tamoxifen, or 5 ppm tamoxifen in the DHPN-treated groups, and 0 or 500 ppm of atrazine in the DHPN-untreated groups for 24 weeks. At autopsy major organs, including the thyroid, pituitary, liver, kidney, testis, epididymis, and brain, were collected and histopathologically examined. Body weights were significantly (P<0.05) decreased by the high doses of atrazine or tamoxifen, the effect being enhanced in combination. Relative thyroid weights were significantly increased (P<0.05) only in the tamoxifen-treated group and pituitary weights were elevated with 500 ppm atrazine plus tamoxifen (P<0.05). Relative liver weights were increased by the high dose of atrazine. However, the atrazine and/or tamoxifen treatments did not induce significant histopathological changes in the major organs, including the thyroid, nor cause significant changes in serum TSH levels. These results suggest that neither atrazine nor tamoxifen may promote thyroid carcinogenesis, alone as well as in combination.     

Heterogeneity of IgE response to TDI-HSA conjugates by ELISA in toluene diisocyanate (TDI) -induced occupational asthma (OA) patients.

Toluene diisocyanate (TDI), a low molecular weight reactive chemical, is known to be a main cause of occupational asthma (OA) in Korea. Although it is thought that inhaled TDI may act as a hapten, the precise mechanisms of TDI-induced OA are unknown. In this study, TDI-human serum albumin (HSA) conjugates (5, 10, 20 and 30 min) were prepared in the range of 1.5 to 5.0 TDI mole/HSA mole. Specific binding of serum IgE to TDI-HSA (30 min) was observed using IgE ELISA as well as ELISA inhibition assay. Around 40% of TDI-induced OA patients were positive for serum specific IgE by ELISA. Degrees of serum IgE binding were different depending on which TDI-HSA conjugate was used as an antigen. Moreover, binding patterns were different depending on the individuals. Interestingly, higher binding of IgE to TDI-HSA (5 min) than to TDI-HSA (30 min) which was more highly substituted was observed in some patients. Probably new antigenic epitopes on carrier proteins were targets of the specific IgE. The results of this study indicated that IgE responses to TDI-HSA conjugates were heterogeneous in TDI-induced OA patients and self-proteins modified by reactive chemicals can become a major target antigen of IgE in certain cases.     

A comparison of coarctation resection and subclavian flap angioplasty using ultrasonographically monitored postocclusive reactive hyperemia

The reported relatively high incidence of early restenosis at the coarctation repair site with subclavian flap angioplasty, especially in infants less than 3 months of age, prompted a physiologically oriented analysis of relief of obstruction from coarctation after subclavian flap angioplasty versus resection and end-to-end anastomosis in infancy. Twenty-one patients who had undergone repair of coarctation in infancy by either subclavian flap angioplasty (nine patients) (median age 8 years) or resection and end-to-end anastomosis (12 patients) (median age 8 years) were evaluated by Doppler spectrum analysis of the blood flow velocities in the femoral artery at rest and during reactive hyperemia. The median resting right upper to lower limb systolic pressure difference (with interquartile range) was similar in the angioplasty, resection and anastomosis, and control groups: -5 mm Hg (18 mm Hg), 0 mm Hg (12 mm Hg), and -2.5 mm Hg (10 mm Hg), respectively. Also, similar resting values for the maximum frequency of the advancing curve and the pulsatility and resistance indices were measured in the three groups. During reactive hyperemia of the leg, however, a significant hemodynamic obstruction across the repair site became clinically manifest in the angioplasty group only, as documented by a lower pulsatility index in comparison with the control group (p = 0.01, Mann-Whitney U test). Comparison of the hemodynamic results between the angioplasty and resection and anastomosis groups in subdivisions of infants operated on at an age of less or greater than 3 months, both at rest and during reactive hyperemia, showed, already at rest, a significantly lower value for the pulsatility index in the former angioplasty subdivision (p = 0.05, Student's t test), indicating a significant resistance at the coarctation repair site in the angioplasty patients operated on before the third month of life. A disadvantage of angioplasty (compared with resection and anastomosis) was noted when angioplasty was performed before the third month of life, and an unequivocal lack of advantage was noted when performed beyond that period regarding relief of obstruction from coarctation. In addition, a definite potential for adverse long-term effects on the hemodynamics of the left upper limb after subclavian flap angioplasty in infancy has been documented. For these reasons we prefer to perform resection and end-to-end anastomosis for repair of coarctation in infancy.     

Specificity of co-promoting effects of caffeine on thyroid carcinogenesis in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine

The specificity of copromotion effects of caffeine with known goitrogenic factors on thyroid carcinogenesis was examined in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine (DHPN). Male F344 rats were divided into 8 groups, each consisting of 10 animals, and received a single sc injection of 2,800 mg/kg DHPN. From one week after the DHPN initiation, they were given basal diet, iodine deficiency (ID) diet, 500 ppm phenobarbital (PB) solution or 1,000 ppm sulfadimethoxine (SDM) solution with or without 1,500 ppm caffeine feeding for 12 weeks. The caffeine, PB, SDM, and ID treatments significantly (p < 0.05 or 0.01) increased the relative thyroid weights, and the increases with PB or ID were further (p < 0.05 or 0.01) enhanced in combination with caffeine. SDM drastically promoted thyroid carcinogenesis in association with increased serum TSH levels regardless of the caffeine treatment. Thyroid follicular carcinomas and adenomas were more frequently observed in the additional caffeine groups than in the ID alone groups. The incidence and multiplicity of focal thyroid follicular hyperplasias in the ID-treated groups were significantly (p < 0.05 and 0.01) elevated in the case of combination with caffeine. Increases in serum TSH levels with PB or ID were also further enhanced in combination with caffeine. Serum thyroid hormone levels were significantly (p < 0.01) decreased by SDM but significantly (p < 0.05 or 0.01) increased by caffeine, PB or ID. Our results clearly indicate that dietary caffeine at a high dose of 1,500 ppm interacts with ID, but neither SDM nor PB, to promote rat thyroid carcinogenesis although the combined caffeine + PB treatment somewhat affected thyroid weights as well as thyroid hormone levels.     

Serum pregnancy-specific beta1-glycoprotein before embryo transfer is related to endometrial thickness and to outcome prognosis in women undergoing in-vitro fertilization treatment

We have previously observed the repeated presence of low but detectable amounts of the trophoblast marker pregnancy-specific beta1-glycoprotein (SP1) in the serum of some women undergoing in-vitro fertilization (IVF) treatment around the time of oocyte retrieval. The occurrence of these signals seemed to be restricted to a defined group of patients which also showed a lower pregnancy success rate in a preliminary study. To test our hypothesis we have analysed 173 consecutive cycles leading to an embryo transfer. Fifty-four cycles (31%) had a serum SP1 level of at least 0.1 ng/ml between days embryo transfer -5 and embryo transfer (group A). Five pregnancies were obtained in this group (pregnancy rate = 9.3%), while in group B, defined by the absence of detectable SP1 before embryo transfer (119 cycles), 36 ongoing pregnancies were achieved (30.3%). Ten of the 41 pregnancies were achieved in 33 first-time non-pregnant patients undergoing further attempts during the study period. Again the pregnancy rate was higher in the first-time group B women (9/23 versus 1/10 for group A). Patients tended to remain in their groups A or B, the latter being associated with a better immediate as well as subsequent chance for pregnancy. Group A cycles had a significantly lower endometrial thickness two days before oocyte retrieval than group B (P = 0.0011). We postulate that the presence of an unknown, maternal and progesterone- or follicle stimulating hormone-independent factor in some patients could stimulate tonic ectopic SP1 synthesis and at the same time negatively influence endometrial development.      

Reticuloendothelial Fc receptor function in SLE patients. I. Primary HLA linked defect or acquired dysfunction secondary to disease activity?

Reticuloendothelial system (RES) Fc receptor-mediated immune clearance was measured in 18 patients with systemic lupus erythematosus (SLE). Only two patients, with major disease activity, had a prolonged T 1/2 of the blood disappearance curve of injected IgG coated red cells in comparison to 22 healthy controls. Circulating immune complexes (CIC) were studied with three methods: PEG precipitation, C1q-ELISA and the indirect granulocyte phagocytosis test (IGFT). The T 1/2 of the blood disappearance curve related significantly to the IGFT (r = 0.55, P less than 0.05) and not to the PEG and C1q-ELISA test. Although HLA-DR3 phenotype frequency was significantly increased in our SLE population (P less than 0.05), it was not related to Fc receptor function. Similarly, HLA-DR2 phenotype was not related to RES Fc receptor function. These data do not support the concept that a genetic HLA linked defect in reticuloendothelial Fc receptor function is a primary cause of SLE, predisposing the inflicted individual to immune complex deposition. However, Fc receptor-mediated immune clearance seems to be related to disease activity itself and to levels of CIC.