Devising genuine spatial correlation functions

The choice of the mathematical form of spatial correlation functions for optical fields is restricted by the constraint of nonnegative definiteness. We discuss a sufficient condition for ensuring the satisfaction of such a constraint.

Maternal and neonatal outcome after cesarean section: the impact of anesthesia

BACKGROUND

Among the anesthetic technologies used, regional anesthesia is becoming the most common in cesarean section (CS) deliveries. Aim. This retrospective survey examined the variables taken into account when selecting the anesthetic technique to be used, and how this choice affects the outcome for the mother and the newborn.

METHODS

One thousand eight hundred and seventy elective and emergency CS were evaluated for anesthetic technique used, indications, and maternal and neonatal outcome.

RESULTS

Of the 611 elective CS (32.6%), 206 (33.8%) were performed under general anesthesia and 405 (66.2%) under regional anesthesia. Of the 1259 emergency CS performed (67.4%), 525 (41.9%) were under general anesthesia and 734 (58.1%) under regional anesthesia. Conditions associated with a newborn 1-minute Apgar score of <7 were general anesthesia and multiple pregnancy (p<0.01); a 5-minute Apgar score of <7 was only associated with multiple pregnancy. The most important factor for very low Apgar scores was the presence of fetal malformations. Whatever the chosen technique, neither maternal deaths directly or indirectly due to the anesthesia nor major maternal and perinatal complications were found.

CONCLUSIONS

This survey confirms the preference for regional anesthesia during elective cesarean sections and for general anesthesia in emergency situations. Moreover, newborn outcome was found not to be influenced either by the technique used or by the character of the procedure.

[Tocolysis: which are the benefits?]

Spontaneous preterm labor is still a major problem in perinatal medicine and it is associated to overwhelming risks of neonatal morbidity and mortality. Delaying delivery for hours, days or sometimes weeks may greatly reduce the short- and long-term perinatal morbidity improving fetal maturity of several organs and systems. Inhibition of uterine contractions may in fact allow to take advantage of the prenatal administration of glucocorticosteroids, which have been shown to reduce the incidence and severity of newborn respiratory distress syndrome. Moreover, delaying delivery may allow the transfer in utero to a maternity attached to a neonatal intensive care unit, therefore guaranteeing the best care for the preterm newborn. Every day gained between 22 and 28 weeks gestation increases survival by 3%. However, since most of preterm deliveries happened to be after 29 weeks, newborn survival is a secondary issue while the main aim of delaying labor in these cases is to improve the function of fetal systems and to try to understand if it is the case of prolonging pregnancy balancing risks of a hostile intrauterine environment towards the possible complications of a premature extrauterine life.

[Approach to the study of vasculitides: general aspects and classification]

Since etiology and pathogenesis of most systemic and/or isolated vasculitides are unknown, any attempt to make a rational classification of these entities is far from being perfect. Vasculitis may be a primary disease or it may be associated with connective tissue diseases, infectious diseases, neoplasms, drug assumption, allograft rejection and so on. As secondary vasculitides constitute the majority of cases, diagnosis of primary vasculitis is made by exclusion. At the present time, the 1993 Chapel Hill Consensus Conference on Nomenclature of Primary Vasculitides provides a useful guide to clinician and pathologist for evaluating a patient with an idiopathic form of vasculitis. This classification is based on the predominant size of vessels affected and describes the main clinico-pathologic features of the various clearly defined types of systemic vasculitis. Though it suffers from omissions and contradictions, in routine practice it is of great help to distinguish diseases in this intriguing chapter of pathology.

[Nurses' professional responsibility]

As managed care relevance is growing, several old issues related to personal institutional responsibility are increasing among practitioners. Therefore, as a professional figure a nurse bases his/her job on a mix of personal knowledge and skills along with training, and he/she is responsible for giving advice in line with professional care standards. In addition, he/she is in charge of the treatment pattern agreed with the patient. However, nursing is a much more complex job, which leads professional figures facing the controversial issue of combining institutional responsibility and nursing professional tasks and duties daily. As far as nursing institutional responsibility is concerned, different view points or approaches can be applied to investigate it. The most common one is the legal approach, yet this is not the most appropriate one. Therefore, our professional background is mainly based on a management prospective rather than a legal one; dealing with the issue legally would lead, essentially, to a summary of laws and regulations without any kind of argumentative discussion. Consequently, this study aimed to analyze nurses' institutional responsibility by approaching the issue from an innovative human resources management prospective; therefore, defining the gap between nursing institutional responsibility and its tasks.

Cloning and characterization of a novel WD-40 repeat protein that dramatically accelerates osteoblastic differentiation

The bone morphogenetic proteins (BMPs) play a pivotal role in endochondral bone formation. Using differential display polymerase chain reaction, we have identified a novel gene, named BIG-3 (BMP-2-induced gene 3 kb), that is induced as a murine prechondroblastic cell line, MLB13MYC clone 17, acquires osteoblastic features in response to BMP-2 treatment. The 3-kilobase mRNA encodes a 34-kDa protein containing seven WD-40 repeats. Northern and Western analyses demonstrated that BIG-3 mRNA and protein were induced after 24 h of BMP-2 treatment. BIG-3 mRNA was expressed in conditionally immortalized murine bone marrow stromal cells, osteoblasts, osteocytes, and growth plate chondrocytes, as well as in primary calvarial osteoblasts. Immunohistochemistry demonstrated that BIG-3 was expressed in the osteoblasts of calvariae isolated from mouse embryos. To identify a role for BIG-3 in osteoblast differentiation, MC3T3-E1 cells were stably transfected with the full-length coding region of BIG-3 (MC3T3E1-BIG-3) cloned downstream of a cytomegalovirus promoter in pcDNA3.1. Pooled MC3T3E1-BIG-3 clones expressed alkaline phosphatase activity earlier and achieved a peak level of activity 10-fold higher than cells transfected with the empty vector (MC3T3E1-EV) at 14 days. Cyclic AMP production in response to parathyroid hormone was increased 10- and 14-fold at 7 and 14 days, respectively, in MC3T3E1-BIG-3 clones, relative to MC3T3E1-EV clones. This increase in cAMP production was associated with an increase in PTH binding. Expression of BIG-3 increased mRNA levels encoding Cbfa1, type I collagen, and osteocalcin and accelerated formation of mineralized nodules. In conclusion, we have identified a novel WD-40 protein, induced by BMP-2 treatment, that dramatically accelerates the program of osteoblastic differentiation in stably transfected MC3T3E1 cells.

Leptin reduces ovariectomy-induced bone loss in rats

Bone mineral density increases with fat body mass, and obesity has a protective effect against osteoporosis. However, the relationship between fat body mass and bone mineral density is only partially explained by a combination of hormonal and mechanical factors. Serum leptin levels are strongly and directly related to fat body mass. We report here the effects of leptin administration compared with estrogen therapy on ovariectomy-induced bone loss in rats. Leptin was effective at reducing trabecular bone loss, trabecular architectural changes, and periosteal bone formation. Interestingly, the combination of estrogen and leptin further decreased bone turnover compared with that in estrogen-treated ovariectomized rats. Leptin also significantly increased osteoprotegerin mRNA steady state levels and protein secretion and decreased RANK ligand mRNA levels in human marrow stromal cells in vitro. Our findings suggest that leptin could modulate bone remodeling in favor of a better bone balance in rats. This study is the first evidence that leptin therapy has a significant effect in preventing ovariectomy-induced bone loss, and this effect may at least in part be mediated by the osteoprotegerin/RANK ligand pathway.

Polarization basis for vortex beams

Attention is called to a polarization basis formed by four Jones vectors that is reducible to two basic structures. In these states the field is linearly polarized at any point, but the polarization direction changes with the angular coordinate. Very simple equations hold for the field lines of these basis vectors. The adoption of this basis is of interest for beams possessing a single vortex of any order, say, m, as well as for beams with two vortices of opposite charges, m and -m. As an example, the application to vectorial Bessel-Gauss beams is briefly discussed.

Fibromodulin is expressed by both chondrocytes and osteoblasts during fetal bone development

Fibromodulin, a keratan-sulfate proteoglycan, was first isolated in articular cartilage and tendons. We have identified fibromodulin as a gene regulated during BMP-2-induced differentiation of a mouse prechondroblastic cell line. Because expression of fibromodulin during endochondral bone formation has not been studied, we examined whether selected cells of the chondrocytic and osteoblastic lineage expressed fibromodulin. Fibromodulin mRNA was detected in conditionally immortalized murine bone marrow stromal cells, osteoblasts, and growth plate chondrocytes, as well as in primary murine calvarial osteoblasts. We, therefore, investigated the temporo-spatial expression of fibromodulin in vivo during endochondral bone formation by in situ hybridization. Fibromodulin was first detected at 15.5 days post coitus (dpc) in the perichondrium and proliferating chondrocytes. Fibromodulin mRNA was also detected at 15.5 dpc in the bone collar and periosteum. At later time points fibromodulin was expressed in the primary spongiosa and the endosteum. To determine whether fibromodulin was expressed during intramembranous bone formation as well, in situ hybridization was performed on calvariae. Fibromodulin mRNA was present in calvarial osteoblasts from 15.5 dpc. These results demonstrate that fibromodulin is developmentally expressed in cartilage and bone cells during endochondral and intramembranous ossification. These findings suggest that this extracellular matrix protein plays a role in both endochondral and intramembranous bone formation.

The expression of osteoprotegerin and RANK ligand and the support of osteoclast formation by stromal-osteoblast lineage cells is developmentally regulated

The one or more molecular mechanisms that determine the obligatory sequence of resorption followed by formation during bone remodeling is unclear. RANK ligand (RANK-L) is an essential requirement for osteoclastogenesis, and its activity is neutralized by binding to the soluble decoy receptor, osteoprotegerin (OPG). Because both molecules are produced by osteoblast lineage cells, we studied their developmental regulation in a conditionally immortalized human marrow stromal (hMS[2-15]) cell line. These cells can simulate the complete developmental sequence from undifferentiated precursor(s) to cells with the complete osteoblast phenotype that are capable of forming mineralized nodules. During osteoblast differentiation, RANK-L messenger RNA levels decreased by 5-fold, whereas OPG messenger RNA levels increased by 7-fold, resulting in a 35-fold change in the RANK-L/OPG ratio. OPG protein also increased by 6-fold. Mouse bone marrow cells generated osteoclast-like cells in coculture with undifferentiated hMS(2-15) cells, but did not when cocultured with hMS(2-15) cells in varying stages of differentiation, unless an excess of RANK-L was added. Thus, undifferentiated marrow stromal cells with a high RANK-L/OPG ratio can initiate and support osteoclastogenesis, but after differentiation to the mature osteoblast phenotype, they cannot. We speculate that the developmental regulation of OPG and RANK-L production by stromal/osteoblast cells contributes to the coordinated sequence of osteoclast and osteoblast differentiation during the bone remodeling cycle.

Use of the van Cittert-Zernike theorem for partially polarized sources

We introduce an extension of the van Cittert-Zernike theorem to spatially incoherent sources with partial polarization. We show through a simple example that fields generated by such sources can possess correlation matrices with interesting properties. In particular, we show that by suitable modulation of the polarization state across the incoherent source, the correlation between the orthogonal components of the field as well as the degree of polarization may drastically change on propagation.

Extraskeletal mesenchymal chondrosarcoma involving the heart: report of a case

Extraskeletal mesenchymal chondrosarcoma is a rare tumor frequently arising in the meninges and lower limbs. We describe a case of mesenchymal chondrosarcoma involving the heart in a 39-year-old man who presented with fever, chest pain and shortness of breath. His clinical course was rapid, leaving insufficient time for a complete diagnostic work-up, and the patient died 2 months after the onset of symptoms.

Effects of androgens on the insulin-like growth factor system in an androgen-responsive human osteoblastic cell line

Although androgens have significant effects on bone metabolism, the mediators of their effects are still unclear. As the insulin-like growth factors (IGFs) and IGF-binding proteins (IGFBPs) have important effects on osteoblast proliferation and differentiation, we examined androgen effects on the IGF system in a conditionally immortalized human fetal osteoblastic cell line, hFOB/AR-6, which displays a mature osteoblastic phenotype and physiological levels of functional androgen receptors. The nonaromatizable androgen, 5alpha-dihydrotestosterone (5alphaDHT), and testosterone, but not dehydroepiandrosterone, increased IGF-I messenger RNA (mRNA) levels up to 4-fold in a dose (10(-12)-10(-6) M)- and time (2-72 h)-dependent fashion. These changes were prevented by the specific androgen receptor antagonist, hydroxyflutamide. In addition, 5alpha-DHT decreased IGFBP-4 mRNA and protein levels by 2- and 4-fold, respectively, and increased IGFBP-2 and -3 mRNA and protein levels by 6- and 7-fold (for mRNA) and 3- and 5-fold (for protein), respectively. hFOB/AR-6 cells expressed the type-I IGF receptor, but this was not regulated by 5alphaDHT. 5alphaDHT and IGFBP-3 specifically increased hFOB/AR-6 cell proliferation, and a monoclonal antibody specific for IGF-I blocked this effect. Thus, androgens increase the expression of IGF-I, IGFBP-2, and IGFBP-3, but decrease levels of the inhibitory IGFBP-4 in an androgen-responsive human osteoblastic cell line. Our data are consistent with the hypothesis that the effects of androgen on bone cells may be mediated at least in part by increases in IGF-I production and by differential regulation of IGFBPs.

Response of bipotential human marrow stromal cells to insulin-like growth factors: effect on binding protein production, proliferation, and commitment to osteoblasts and adipocytes

Insulin-like growth factors (IGFs) are important regulators of the activity of mature osteoblasts, but their effects on osteoprogenitor cells in human bone marrow stroma are unclear. In this study, we assessed the effects of IGFs on a conditionally immortalized human marrow stromal cell line, hMS(3-4), which has the ability to differentiate to either mature osteoblasts or adipocytes. hMS(3-4) cells expressed functional receptors for IGFs as well as specific IGF-binding proteins (IGFBP-3, -4, -5, and -6). IGF treatment of hMS(3-4) cells did not alter IGFBP expression, but resulted in distinct posttranslational modifications of secreted IGFBP-3 and IGFBP-4 proteins. IGF-I, IGF-II, and their receptor-activating analogs significantly increased by 2-fold the proliferation rate of the hMS(3-4) cells, but had a more complex effect on hMS(3-4) cell differentiation. Treatment with IGFs did not affect gene expression of Cbfa1 or peroxisome proliferator-activated receptor gamma2 (transcription factors involved in commitment to osteoblast and adipocyte pathways, respectively), alkaline phosphatase, type I collagen, and osteocalcin (markers of the osteoblast lineage), or lipoprotein lipase and adipsin (markers of the adipocyte lineage) and did not change alkaline phosphatase activity or type I collagen and osteocalcin protein relative to total protein production. In contrast, IGFs significantly increased type I collagen expression in differentiated hMS(3-4) cells as well as mature osteoblasts and promoted lipid accumulation in differentiated adipocytes. In summary, hMS(3-4) cells express essential components of the IGF system and respond to IGF treatment with increased proliferation. There was no evidence for IGFs directly modulating the commitment of hMS(3-4) cells to either osteoblast or adipocyte pathways, and their effects on differentiation within these lineages were dependent on the stage of cell maturation.

Stimulation of osteoprotegerin ligand and inhibition of osteoprotegerin production by glucocorticoids in human osteoblastic lineage cells: potential paracrine mechanisms of glucocorticoid-induced osteoporosis

Osteoporosis is a serious complication of systemic glucocorticoid use. However, while glucocorticoids increase bone resorption in vitro and in vivo, the mechanism(s) of this effect are at present unclear. Recent studies have identified the osteoprotegerin (OPG) ligand (OPG-L) as the final effector of osteoclastogenesis, an action that is opposed by the soluble neutralizing receptor, OPG. Thus, we assessed glucocorticoid regulation of OPG and OPG-L in various human osteoblastic lineage cells using Northern analysis, RT-PCR, and ELISA. Dexamethasone inhibited constitutive OPG messenger RNA (mRNA) steady-state levels by 70-90% in primary (MS) and immortalized stromal cells (hMS), primary trabecular osteoblasts (hOB), immortalized fetal osteoblasts (hFOB), and osteosarcoma cells (MG-63). In hFOB cells, dexamethasone inhibited constitutive OPG mRNA steady-state levels in a dose- and time-dependent fashion by 90%, and also suppressed cytokine-stimulated OPG mRNA steady-state levels. Dexamethasone-induced inhibition of OPG mRNA levels was not affected by the protein synthesis inhibitor, cycloheximide, and was shown to be due to inhibition of OPG gene transcription using a nuclear run-on assay. Moreover, dexamethasone also dose dependently (10(-10) M-10(-7) M) inhibited constitutive OPG protein concentrations in the conditioned medium of hFOB cells from 2.59 +/- 0.02 ng/ml (control) to 0.30 +/- 0.01 ng/ml (88% inhibition; P < 0.001 by ANOVA). Concurrently, dexamethasone stimulated OPG-L mRNA steady-state levels in MS and hFOB cells by 2- and 4-fold, respectively. Treatment of murine marrow cultures with conditioned medium harvested from dexamethasone-treated MG-63 cells increased tartrate-resistant acid phosphatase (TRAP) activity by 54% (P < 0.005) compared with medium harvested from control-treated cells (in the presence of OPG-L and macrophage colony-stimulating factor). Moreover, dexamethasone (10(-8) M) promoted osteoclast formation in vitro, as assessed by a 2.5-fold increase of TRAP activity in cell lysates (P < 0.001) and the appearance of TRAP-positive multinucleated cells. Our data are thus consistent with the hypothesis that glucocorticoids promote osteoclastogenesis by inhibiting OPG and concurrently stimulating OPG-L production by osteoblastic lineage cells, thereby enhancing bone resorption.

Evaluation of the modal structure of light beams composed of incoherent mixtures of Hermite-Gaussian modes

A new, to our knowledge, technique for determining the modal content of partially coherent beams that are made up of an incoherent superposition of Hermite-Gaussian modes is studied. The algorithm makes use of the intensity profile of the beam at an arbitrarily chosen transverse plane. Analytical derivations are presented for a Gaussian Schell-model source and flat-topped beams, as well as an analysis of their performances in the presence of experimental errors and noise. Numerical simulations are performed to test the accuracy and the stability of the recovery algorithm.

Differentiation of human marrow stromal precursor cells: bone morphogenetic protein-2 increases OSF2/CBFA1, enhances osteoblast commitment, and inhibits late adipocyte maturation

Because regulation of the differentiation to osteoblasts and adipocytes from a common progenitor in bone marrow stroma is poorly understood, we assessed effects of bone morphogenetic protein-2 (BMP-2) on a conditionally immortalized human marrow stromal cell line, hMS(2-6), which is capable of differentiation to either lineage. BMP-2 did not affect hMS(2-6) cell proliferation but enhanced osteoblast differentiation as assessed by a 1.8-fold increase in expression of OSF2/CBFA1 (a gene involved in commitment to the osteoblast pathway), by increased mRNA expression and protein secretion for alkaline phosphatase (ALP), type I procollagen and osteocalcin (OC) (except for OC protein), and by increased mineralized nodule formation. Transient transfection with Osf2/Cbfa1 antisense oligonucleotide substantially reduced BMP-2-stimulated expression of ALP mRNA and protein. The effects of BMP-2 on adipocyte differentiation varied: expression of peroxisome proliferator-activated receptor gamma2 (a gene involved in commitment to the adipocyte pathway) was unchanged, mRNA expression of the early differentiation marker, lipoprotein lipase, was increased, and mRNA and protein levels of the late differentiation marker, leptin, and the formation of cytoplasmic lipid droplets were decreased. Thus, by enhancing osteoblast commitment and by inhibiting late adipocyte maturation, BMP-2 acts to shunt uncommitted marrow stromal precursor cells from the adipocyte to the osteoblast differentiation pathway.

Influence of thrombolytic therapy on inferior acute myocardial infarction with concomitant anterior ST segment depression

The purposes of this study were to analyze the prognostic significance of precordial ST segment depression and to determine whether thrombolytic therapy is effective for all patients with inferior acute myocardial infarction (AMI) or whether there is a different effectiveness for patients with concomitant anterior ST segment depression persisting for 24 hours or longer. Medical charts of 176 patients were studied. On the basis of ECG the patients were subclassified into three groups according to the presence, persistence, or absence of significant ST segment depression: Group 1: anterior ST segment depression persisting for less than 24 hours (45.4%); Group 2: anterior ST segment depression persisting for more than 24 hours (17.6%); Group 3: no anterior ST segment depression (37%). Age, Killip class, peak creatine kinase, hospital deaths, left ventricular ejection fraction, regional wall motion score, postinfarction angina, and ventricular/supraventricular arrhythmia of all patients were studied. Parameters of the three groups were compared: worse results were found in group 1 and the worst in group 2. This result is independent of thrombolytic therapy. Finally, the same parameters of thrombolyzed and nonthrombolyzed groups were compared: no statistically significant difference was observed. Among thrombolyzed patients the number of those with ST depression lasting more than 24 hours is lower than in nonthrombolyzed patients. It can be assumed that thrombolytic therapy in inferior AMI determines a shifting of patients from a worse prognosis group (ST segment depression persisting for more than 24 hours) to a better prognosis group (ST segment depression persisting for less than 24 hours).

A clinical diagnosis of inadvertent epidural administration of potassium chloride

We present a case of accidental epidural administration of potassium chloride, which was diagnosed by clinical signs. The genesis of symptoms and signs following such administration is discussed and compared with other published reports.

Premature ovarian failure (POF) and fragile X premutation females: from POF to to fragile X carrier identification, from fragile X carrier diagnosis to POF association data

Early menopause in the fragile X carriers has been well documented in several reports. All surveys demonstrated that 13-25% of fragile X carriers experienced premature ovarian failure (POF), defined as menopause before the age of 40 years. In 1995 we started screening two groups of subjects as a part of a Fragile X Research Program: 1) women previously diagnosed as fragile X carriers from the register of our center and 2) women with POF and without a family history of fragile X or other forms of mental retardation. In this study we report the preliminary data collected from 75 fragile X families; in 30 of them, POF was present in one or several subjects, all of whom had a fragile X premutation. None of the women with a full mutation experienced POF in our series of patients. We also identified 89 families without a family history of fragile X or mental retardation, and there were 108 subjects who experienced POF, of which 6.5% had a fragile X premutation. This is 70-fold higher than the background prevalence of fragile X premutation in the Italian population and suggests an association with POF. These data confirm the results of other surveys.