High resolution solid-state 29si nmr spectroscopy of silicone gels used to fill breast prostheses

We have used ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy to study the chemical structure of the silicone gels in virgin and explanted breast prostheses. Despite evidences of alteration in the morphological appearance of the silicone gel inside the breast prosthesis, our results do not reveal changes in the chemical nature and structure of the silicone gels after implantation. In addition to the main ²⁹Si resonance peak at ?22.26 ppm that corresponds to the resonance frequency of the D repeat unit of the polysiloxane chains, the high sensitivity of our NMR technique allows the detection of very low concentrations of silicone compounds. Within our experimental detection limit of 0.2%, no signal between ?90 ppm and ?150 ppm are observed. This indicates that no silica products are present inside the gel of the prostheses. Furthermore, our ²⁹Si NMR spectra indicate differences in the chemical compositions of the silicone gels from different manufacturers.     

Hypercalcemia associated with dysregulation of 1,25-dihydroxyvitamin D in arthritis.

We describe an elderly man who presented with hypercalcemia associated with suppressed intact parathyroid hormone (PTH) levels. Despite renal insufficiency the circulating 1,25-dihydroxyvitamin D (1,25(OH)2D) was in the upper part of the normal range. Known causes of hypercalcemia were absent and mild hypercalcemia with suppression of intact PTH persisted until after bilateral hip replacement for severe arthritis (1 year after presentation). After hip replacement the ionized calcium normalized, intact PTH normalized, and 1,25(OH)2D decreased markedly. We believe the abnormalities in mineral homeostasis were related to production of 1,25(OH)2D by inflammatory mononuclear cells associated with arthritis.     

An open-label efficacy pilot study with pimecrolimus cream 1% in adults with facial seborrhoeic dermatitis infected with HIV

BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients.     

Down-Regulation of Estrogen Receptor Immunoreactivity by 17β-estradiol in the Guinea Pig Forebrain

Low amplitude pulses of estradiol-17β (E₂-17β) are more effective than large single bolus injections or constant exposure to E₂-17β in inducing progesterone-facilitated sex behavior in female rats and guinea pigs. The present study examined whether the increased responsiveness to E₂-17β is due to an increase in the number of estrogen receptors in the estrogen receptor rich areas of the hypothalamus and amygdala. Initial studies examined the rapid effects (20 min) of a high dose of E₂-17β (50 μg) on estrogen receptor immunostaining using either the H222 antibody or the ER 21 antiserum. ER 21 immunostaining was not affected by the E₂-17β treatment suggesting that it binds to both occupied and unoccupied estrogen receptors. Therefore the ER 21 antiserum was used to characterize the regulation of estrogen receptor immunoreactivity (ER-IR) by E₂-17β. ER-IR was examined for 48 h and serum E₂-17β for 24 h following a 2 μg s.c. injection of E₂-17β (a dose similar to that used in multiple pulse paradigms). Serum E₂-17β peaked 15 to 30 min following the injection and returned to baseline values by 1 h. In all but one area maximal suppression of ER-IR occurred at 12 h. In summary, 1) decreases in estrogen receptor immunoreactivity following E₂-17β are consistent with studies in which estrogen receptors were assayed by binding assays and estrogen receptor mRNA was determined by in situ hybridization; 2) the ER 21 antiserum is able to detect both occupied and unoccupied estrogen receptors and 3) H222 immunoreactivity is influenced by the presence of E₂-17β, so that the level of H222-IR is a reflection of ligand/receptor binding dynamics. The data suggest that up-regulation of estrogen receptors does not account for the increase in behavioral sensitivity which is observed following multiple pulses of E₂-17β.     

In-vitro maturation of human germinal vesicle stage oocytes: role of cumulus cells and epidermal growth factor in the culture medium

In-vitro maturation (IVM) of oocytes is a promising technique to reduce the costs and avert the side-effects of gonadotrophin stimulation for in-vitro fertilization (IVF). The pregnancy rates from oocytes matured in vitro are much lower than those of in-vivo stimulation cycles indicating that optimization of IVM remains a challenge. Therefore, we investigated the effect of supplementation of the medium with gonadotrophins, oestradiol and epidermal growth factor (EGF) and the effect of retaining or removing the cumulus cells on nuclear and cytoplasmic maturation of immature oocytes. Human germinal vesicle (GV) oocytes obtained after gonadotrophin stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a complex defined medium either supplemented with gonadotrophins, oestradiol and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and oestradiol alone. The cumulus cells were either removed or kept intact. In GV stage oocytes cultured without cumulus (group I) significantly more oocytes reached the metaphase II (MII) stage at 30 h in media supplemented with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with intact cumulus (group II), more oocytes reached MII at 30 h than in group I, but there was no difference in medium with or without EGF supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of MII oocytes was judged from their capability to activate and fertilize after ICSI. In group I, the rates of activation and normal fertilization were similar. However, in group II, significantly more oocytes underwent normal fertilization in the EGF-supplemented than the unsupplemented group (71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized oocytes were similar in the sibling oocyte subgroups cultured with or without EGF supplementation, but the overall cleavage rates were higher in cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P < 0.001). Thus, supplementation of the maturation medium with EGF and maintenance of the cumulus during culture improve the nuclear and cytoplasmic maturation of human oocytes in vitro.      

Fine-needle aspiration cytology of sarcomatoid renal cell carcinoma: A morphologic and immunocytochemical study of 15 cases

Sarcomatoid renal cell carcinoma (SRCC), which accounts for 5% of all renal cell carcinomas (RCC), has a worse prognosis than conventional nonsarcomatoid RCC. making accurate diagnosis important. This study reports on the morphologic and immunocytochemical features of 15 cases of SRCC (9 primary tumors and 6 metastases) diagnosed by fine-needle aspiration (FNA) biopsy. All but three cases showed a dimorphic cell population consisting of varying proportions of a high-grade epithelial component, either clear or granular-cell type and a spindle cell (sarcomatoid) component, of either fibrosarcomatous, malignant fibrous histiocytoma (MFH), or unclassified types. The sarcomatoid component in the biphasic and monophasic tumors stained positively for cytokeratin in 12 of 14 (85%) cases, for vimentin in 10 of 11 (91 %) cases, and for muscle-specific action in 4 of 11 (36%) cases. Of note, the three cases that demonstrated a purely sarcomatoid morphology stained positively for cytokeratin. Unlike in studies performed on surgically resected specimens, neither the proportion of the sarcomatoid component nor the presence of necrosis had prognostic significance, the discrepancy most likely being related to the sampling. We conclude that SRCC, both primary and metastatic, can be accurately diagnosed by FNA when cytologic features are evaluated in conjunction with immunocytochemical findings.