Syndromic presentation of a pleuropulmonary blastoma associated with congenital cystic adenomatoid malformation. A case report

Pleuropulmonary blastoma (PPB) is a rare malignant mesenchymal pediatric tumor with a well-recognized association with congenital cystic adenomatoid malformation (CCAM). Recently, it has been described in a patient with CCAM, multiple jejunal polyps, and cystic nephroma. We describe a similar case of a unique presentation of PPB, arising in association with CCAM and with a history of intussception caused by multiple small bowel polyps.     

Effect of vitamin K<Subscript>2</Subscript> and growth hormone on the long bones in hypophysectomized young rats: a bone histomorphometry study

The purpose of the present study was to determine whether vitamin K₂ and growth hormone (GH) had an additive effect on the long bones in hypophysectomized young rats. Forty-eight female Sprague–Dawley rats (6 weeks old) were assigned to the following five groups by the stratified weight randomization method: intact controls, hypophysectomy (HX) alone, HX + vitamin K₂ (30 mg/kg, p.o., daily), HX + GH (0.625 mg/kg, s.c., 5 days a week), and HX + vitamin K₂ + GH. The duration of the experiment was 4 weeks. HX resulted in a reduction of the cancellous bone volume/total tissue volume (BV/TV) at the proximal tibial metaphysis, as well as decreasing the total tissue area and cortical area of the tibial diaphysis. These changes resulted from a decrease of the longitudinal growth rate and the bone formation rate (BFR)/TV of cancellous bone, as well as a decrease of the periosteal BFR/bone surface (BS) and an increase of endocortical bone turnover (indicated by the BFR/BS) in cortical bone. Administration of vitamin K₂ to HX rats did not affect the cancellous BV/TV or the cortical area. On the other hand, GH completely prevented the decrease of total tissue area and cortical area in cortical bone, as well as the decrease of marrow area and endocortical circumference, by increasing the periosteal BFR/BS compared with that in intact controls and reversing the increase of endocortical bone turnover (BFR/BS). However, GH only partly improved the reduction of the cancellous BV/TV, despite an increase of the longitudinal growth rate and BFR/TV compared with those of intact controls. When administered with GH, vitamin K₂ counteracted the reduction of endocortical bone turnover (BFR/BS) and circumference caused by GH treatment, resulting in no significant difference of marrow area from that in untreated HX rats. These results suggest that, despite the lack of an obvious effect on bone parameters, vitamin K₂ normalizes the size of the marrow cavity during development of the bone marrow in young HX rats treated with GH.     

Differential retention of alpha-vitamin E is correlated with its transporter gene expression and growth inhibition efficacy in prostate cancer cells

BACKGROUND: Epidemiological studies showed Vit E has protective effects against prostate cancer (PCa). Interestingly, different prostate cancer cells have different sensitivity to alpha-Vit E or VES treatment. The goal of this study is to determine whether cellular Vit E bioavailability and its transport proteins are important contributing factors. METHODS: alpha-Vit E and its ester form, VES, were used to treat prostate cancer LNCaP, PC3, and DU145 cells, and their growth rates were determined by MTT assay. Cellular levels of Vit E were quantified using HPLC as the index of bioavailability. The expression levels of Vit E transport proteins were determined by real-time PCR. RESULTS: Among these PCa cells, only LNCaP cells were sensitive to 20 microM alpha-Vit E treatment, while both LNCaP and PC3 cells were sensitive to 20 microM VES treatment. Coordinately, cellular levels of alpha-Vit E and VES positively correlated to their inhibitory effects. Further study found expression levels of Vit E transport proteins, including tocopherol associated protein (TAP), scavenger receptor class B type I (SR-BI), alpha-tocopherol transfer protein (TTP), and ATP binding cassette transporter A1 (ABCA1), were different in various PCa cells, which may contribute to cellular Vit E bioavailability. This notion is further supported by the findings that overexpression or knockdown of TTP could coordinately alter cellular alpha-Vit E levels in PCa cells. CONCLUSION: Antiproliferative efficacy of alpha-Vit E is correlated with its cellular bioavailability in PCa cells. Modulating the expression of the efflux or influx transporters could sensitize the growth inhibition efficacy of Vit E in prostate cancer cells.     

Parathyroid hormone assay predicts hypocalcaemia after total thyroidectomy

BACKGROUND: Postoperative parathyroid gland function after total thyroidectomy (TT) has traditionally been monitored by the measurement of serum calcium concentrations. The purpose of this study is to determine whether measurement of parathyroid hormone (PTH) concentrations in the early postoperative period accurately predicts patients at risk of developing hypocalcaemia. METHODS: A prospective cohort study of patients undergoing TT was carried out. PTH concentrations were measured preoperatively and at 4 and 23 h postoperatively. Serum calcium concentration was measured preoperatively and twice daily for 48 h after surgery. RESULTS: One hundred patients undergoing TT were recruited into the study in the period June 2004 to July 2005. Benign multinodular goitre was the most common indication for surgery (77%). The incidence of temporary hypocalcaemia (Ca < 2.0 mmol/L) was 18%. The mean PTH concentration at 4 h after surgery was 22.3 ng/L and was not significantly different from the 23-h concentration of 23.2 ng/L (P = 0.18). A PTH concentration of < or = 3 ng/L measured at 4 h after surgery had a sensitivity, specificity and likelihood ratio of 0.71, 0.94 and 11.3, respectively, for predicting postoperative hypocalcaemia. The accuracy of a single PTH concentration at 4 h was good for predicting hypocalcaemia (area under receiver-operator characteristic curve 0.90; confidence interval 0.81-0.96). There was no significant difference in accuracy between the 4- and 24-h PTH concentrations (P = 0.14). CONCLUSIONS: A single measurement of PTH concentration in the early postoperative period after TT reliably predicts patients who are likely to develop hypocalcaemia. This approach facilitates early discharge and may decrease the need for multiple postoperative blood tests.     

Differential Effect of Diarrhea on FK506 Versus Cyclosporine A Trough Levels and Resultant Prevention of Allograft Rejection in Renal Transplant Recipients

Diarrhea is the most frequently reported adverse event in patients treated with mycophenolate mofetil. Twenty-six renal transplant patients on a mycophenolate mofetil-based immunosuppressive regime with persistent afebrile diarrhea were examined. Diarrhea caused a significant rise in FK-506 trough levels despite intake of stable doses, necessitating FK-506 dose reductions of 30% to obtain pre-diarrhea trough levels. In contrast, trough levels of cyclosporine A remained stable without dose adjustments. This suggests that absorption and/or metabolism is differentially altered for FK506 compared with cyclosporine A in patients with diarrhea. In nine patients mycophenolate mofetil was reduced or stopped because of persistent diarrhea without identifiable cause. This resulted in end-stage renal disease because of chronic rejection in two patients, and in acute rejection in two patients, all taking FK506 and steroids. Therefore, dose adjustments of FK506 in patients with diarrhea must be carefully monitored, especially when doses of mycophenolate mofetil are also reduced.     

Hormone levels in middle-aged and elderly men with and without erectile dysfunction in Taiwan

The change in sexual hormones with age in middle-aged and elderly Chinese men, with and without erectile dysfunction (ED), was investigated. Total testosterone (TT), free testosterone (FT), dehydroepiandrosterone sulfate (DHEAS), and sex hormone-binding globulin (SHBG) were determined from fasting serum samples by radioimmunoassay in 627 middle-aged and elderly ethnic Chinese men with and without ED. Calculated FT was derived from TT and SHBG. Patients with ED were subdivided into groups having low serum TT (<2.7 ng/ml) and normal TT (> or =2.7 ng/ml). FT and DHEAS declined and SHBG rose with age in both normal patients and in patients with ED. TT and SHBG were lower in patients with ED than in normal subjects at all ages. In contrast to findings in previous studies, levels of FT were higher in patients with ED than in normal subjects. Hormonal changes in this Chinese population generally mirrored those in previously studied ethnic populations, except for higher FT in patients with ED. This suggests that hormonal levels in patients with ED may vary in different populations. The significance and reproducibility of this finding remains to be determined.     

Immunohistochemical characterization of the 'intimal proliferation' phenomenon in Sneddon's syndrome and essential thrombocythaemia

Cellular changes were immunocytochemically characterized in skin vessels of five patients with idiopathic generalized racemose livedo (Sneddon's syndrome), and one patient with localized racemose livedo associated with essential thrombocythaemia. Antibodies against α-smooth muscle-actin, tropomyosin, desmin, vimentin, factor VIII-related antigen, human endothelial cells (CD31), human macrophages (CD68), and HLA-DR positive cells (CR3/43) were used. Conventional light microscopy showed, in all cases, intimal thickening of ascending arteries and arterioles as a result of an accumulation of cells and extracellular hyalinized material. None of the specimens showed infiltration with polymorphonuclear leucocytes or macrophages. The cells in the region of the intimal hyperplasia showed intense positive immunostaining for α-smooth muscle actin and tropomyosin. Staining for the intermediate filament desmin was localized to the resident smooth muscle cells of the media, whereas staining for vimentin was found in all types of cells in both the intima and media. Positive immunostaining for factor VIII-related antigen and CD31 was strictly confined to the endothelial cells lining the narrowed lumina of the vessels. No positive staining with either antibody was observed in totally occluded vessels. Cells in the subintimal space did not show reactivity for CD68 in any of the specimens, but two cases showed solitary cells with positive staining for HLA-DR in this region. There were no differences in staining pattern between Sneddon's syndrome and essential thrombocythaemia with any of the antibodies. Our results support the assumption that the ‘intimal proliferation’ in both diseases is caused by colonization of the subendothelial space with contractile cells of possibel smooth muscle origin. The similarities in histopathology and immunocytochemistry might indicate that in both diseases platelet-derived factors play a causative role.     

Relative roles of microdamage and microfracture in the mechanical behavior of trabecular bone.

Compared to trabecular microfracture, the biomechanical consequences of the morphologically more subtle trabecular microdamage are unclear but potentially important because of its higher incidence. A generic three-dimensional finite element model of the trabecular bone microstructure was used to investigate the relative biomechanical roles of these damage categories on reloading elastic modulus after simulated overloads to various strain levels. Microfractures of individual trabeculae were modeled using a maximum fracture strain criterion, for three values of fracture strain (2%, 8%, and 35%). Microdamage within the trabeculae was modeled using a strain-based modulus reduction rule based on cortical bone behavior. When combining the effects of both microdamage and microfracture, the model predicted reductions in apparent modulus upon reloading of over 60% at an applied apparent strain of 2%, in excellent agreement with previously reported experimental data. According to the model, up to 80% of the trabeculae developed microdamage at 2% apparent strain, and between 2% and 10% of the trabeculae were fractured, depending on which fracture strain was assumed. If microdamage could not occur but microfracture could, good agreement with the experimental data only resulted if the trabecular hard tissue had a fracture strain of 2%. However, a high number of fractures (10% of the trabeculae) would need to occur for this case, and this has not been observed in published damage morphology studies. We conclude therefore that if the damage behavior of trabecular hard tissue is similar to that of cortical bone, then extensive microdamage is primarily responsible for the large loss in apparent mechanical properties that can occur with overloading of trabecular bone.