Although several dextran-coated iron oxide preparations are in preclinical and clinical use, little is known about the mechanism of uptake into cells. As these particles have been shown to accumulate in macrophages and tumor cells, we performed cellular uptake and inhibition studies with a prototypical monocrystalline iron oxide nanoparticle (MION). MION particles were labeled with fluorescein isothiocyanate or radioiodinated and purified by gel permeation chromatography. Two preparations of MION particles were used in cell experiments: nontreated MION and plasma-opsonized MION purified by gradient density purification. As determined by immunoblotting, opsonization resulted in C3, vitronectin, and fibronectin association with MION. Incubation of cells with fluorescent MION showed active uptake of particles in macrophages both before and after opsonization. In C6 tumor cells, however, intracellular MION was only detectable in dividing cells. Quantitatively, 125I-labeled MION was internalized into cells with uptake values ranging from 17 ng (in 9L gliosarcoma) to 970 ng iron per million cells for peritoneal macrophages. Opsonization increased MION uptake into macrophages sixfold, whereas it increased the uptake in C6 tumor cells only twofold. Results from uptake inhibition assay suggest that cellular uptake of nonopsonized (dextran-coated) MION particles is mediated by fluid-phase endocytosis, whereas receptor-mediated endocytosis is presumably responsible for the uptake of opsonized (protein-coated) particles.

Animals↗

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"Is this a dagger I see before me?"--an audit of stabbings and gunshot wounds in Limerick.

BACKGROUND: According to a recent study in Cardiff, the incidence of stab wounds is 14 per 100,000 population per annum. No such figures are available for Ireland. AIM: To evaluate the incidence, type of injury, medical consequences and outcome of patients with stab or gunshot wounds presenting to the Mid-Western Regional Hospital, Limerick, over a 12 month period. METHOD: A retrospective case study of all stab and gunshot wounds presenting over a 12 month period. RESULTS: Out of 62,000 new presentations to the Accident and Emergency (A&E) department, 101 (0.16%) were stabbings, giving an incidence of 33 per 100,000 population. Twenty-six patients required surgical intervention. There were three deaths. There were 10 gunshot wounds, of which 40% required surgical intervention, with no mortalities. CONCLUSION: The incidence of stab wounds presenting to our institution is high. Although constituting a small percentage of presentations to the A&E department they result in considerable morbidity and surgical activity.

Adolescent↗

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Contralateral groin exploration is not justified in infants with a unilateral inguinal hernia.

BACKGROUND: Contralateral groin exploration in children with unilateral inguinal hernia is still controversial, particularly in infants. The patency rate of processus vaginalis is highest in infants but there are few data on the subsequent risk of contralateral hernia development in infants. In this retrospective study, we aimed to find out the incidence of contralateral inguinal hernia following unilateral inguinal herniotomy in infants aged less than one year. METHODS: All infants who underwent a unilateral Inguinal herniotomy between January 1990 and December 1998 were studied retrospectively. Infants with bilateral hernia (n = 7) were excluded from the study. RESULTS: One hundred and one infants (93 boys and 8 girls) were studied. Median age at operation was 23 (range 2-52) weeks. The herniotomy was right-sided in 75% of the infants. Follow-up ranged from three and a half years to 11 years. A contralateral hernia developed in nine infants (9.0%). One of the initial hernias was incarcerated. Median time from operation to occurrence of contralateral hernia was 18 (range 2-60) months. None of the contralateral hernia was incarcerated. Age, sex, incarceration and side of initial hernia did not influence the development of contralateral hernia. CONCLUSION: The low incidence and benign nature of contralateral hernia development in infants undergoing a unilateral inguinal herniotomy does not justify routine contralateral groin exploration.

Female↗

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Platelet FcIgG receptor: increased expression in female platelets.

Explore the source record for details and available documents.

Adolescent↗

PubMedDate not supplied

Breast cancer screening among ethnically diverse low-income women in a general hospital psychiatry clinic.

Most low-income minority women do not obtain screening mammography on a regular basis. Compliance with recommended breast cancer screening guidelines may be even lower in women with psychiatric illnesses. We investigated compliance with breast cancer screening guidelines among 121 ethnically diverse low-income women recruited from a general hospital psychiatry clinic. Mammography and clinical breast examination (CBE) had been obtained in the previous year by 59% and 70% of the patients 40 years of age and older, respectively. Among patients 20 years of age and older, 42% reported monthly breast self-examination (BSE). Physician recommendation of mammography was the strongest predictor of having obtained both a mammogram and a CBE within the previous year. There was an inverse relationship between breast cancer knowledge and screening mammography. Patients who were Hispanic, more educated, more confident in performing BSE, and whose physicians recommended monthly BSE were more likely to perform BSE monthly. These results highlight the importance of physician recommendation of compliance with screening guidelines for early detection of breast cancer. Because psychiatric patients typically are treated by psychiatrists on a regular and frequent basis, psychiatrists are in a unique position not only to encourage cancer screening but also to monitor patient compliance with their recommendations.

Adult↗

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High-efficiency intracellular magnetic labeling with novel superparamagnetic-Tat peptide conjugates.

A biocompatible, dextran coated superparamagnetic iron oxide particle was derivatized with a peptide sequence from the HIV-tat protein to improve intracellular magnetic labeling of different target cells. The conjugate had a mean particle size of 41 nm and contained an average of 6.7 tat peptides. Derivatized particles were internalized into lymphocytes over 100-fold more efficiently than nonmodified particles, resulting in up to 12.7 x 10(6) particles/cell. Internalized particles localized in cytoplasm and nuclear compartments as demonstrated by fluorescence microscopy and immunohistochemistry. Labeled cells were highly magnetic, were detectable by NMR imaging, and could be retained on magnetic separation columns. The described method has potential applications for in vivo tracking of magnetically labeled cells by MR imaging and for recovering intracellularly labeled cells from organs.

Amino Acid Sequence↗

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Macrocyclic chelators with paramagnetic cations are internalized into mammalian cells via a HIV-tat derived membrane translocation peptide.

A major obstacle to using paramagnetic MR contrast agents for in vivo cell tracking or molecular sensing is their generally low cellular uptake. In this study, we show that a paramagnetically labeled DOTA chelator derivatized with a 13-mer HIV-tat peptide is efficiently internalized into mammalian cells. Intracellular concentrations were attained that were readily detectable by MR imaging using both gadolinium and dysprosium chelates. Using this paradigm, it should be feasible to internalize a variety of chemically different agents into mammalian cells.

Amino Acid Sequence↗

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Asylum and the protection of human rights.

There are now some 18.5 million refugees in the world, many more displaced persons within their own country, and the number in both groups is steadily increasing. Some of the problems of seeking asylum and providing the resources for the individual needs of displaced persons are considered. Small non-governmental agencies such as the Ockenden Venture have a degree of flexibility which is particularly helpful. The increasing reluctance of all countries to offer asylum makes work in the displaced persons' home countries increasingly important and the need for preventive protection more urgent.

England↗

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Whole blood quality assurance control samples for forensic toxicology.

Pilot studies were undertaken to examine the feasibility of preparing freeze-dried whole blood samples containing drugs of interest to be used as assay controls. The availability of such samples will enable analysts and laboratory managers to monitor analytical performance. A pilot batch of freeze-dried blood containing five compounds of forensic significance and a blank blood sample were prepared for reconstitution to 2.5-mL aliquots. Samples of each of these preparations were distributed to 55 laboratories in the USA and UK for analysis. A summary of the results is presented along with comments on the feasibility of producing freeze-dried whole blood samples for use in forensic toxicology.

Animals↗

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Case report. Clostridium perfringens septicemia with detection of phospholipase C activity in the serum.

Clostridium perfringens septicemia with massive hemolysis is described in an elderly woman with refractory anemia. This case is highly unusual in that (1) the diagnosis was made during life by discovery of the organisms on a routine peripheral blood film, and that (2) phospholipase C activity was detected in the serum.

Aged↗

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Pediatric melanoma: are recent advances in the management of adult melanoma relevant to the pediatric population.

PURPOSE: Although melanoma in childhood is a rare condition, there is evidence that it is increasing in frequency. As advances are being made in the understanding and therapy of adult melanoma, we need to consider the relevance of these advances to the pediatric population. PATIENTS AND METHODS: We have reviewed our experience at the University of Colorado Health Sciences Center with the clinical parameters, therapy, and outcomes of melanoma in 27 patients age 16 years or younger and contrasted these to the adult experience. RESULTS: Most cases were diagnosed early with the median thickness of the primary melanoma being 0.75 mm. Six of seven patients who had lymph node metastases develop remain alive at a median follow-up of 62 months. Durable complete responses to a variety of therapies were seen in three of five patients with advanced disease outside the central nervous system. Our experience with sentinel node biopsy, adjuvant interferon, and new therapies for metastatic melanoma were also reviewed and appear to be relevant for younger patients. CONCLUSIONS: The behavior of melanoma in the pediatric population at our center is similar to that seen in adults. The integration of recent advances in the staging and therapy of melanoma in adults would be of benefit to children with this condition.

Adolescent↗

PubMedDate not supplied

A review of selective salpingography and fallopian tube catheterization.

Use of selective salpingography and fallopian tube recanalization has revolutionized the diagnosis and treatment of infertility. Selective salpingography, a diagnostic procedure in which the fallopian tube is directly opacified through a catheter placed in the tubal ostium, has been used since the late 1980s to differentiate spasm from true obstruction and to clarify discrepant findings from other tests. In fallopian tube recanalization, a catheter and guide wire system is used to clear proximal tubal obstructions. The recanalization procedure is simple for interventional radiologists to perform and is successfully completed in most patients (71%-92%). Pregnancy rates after the procedure have been variable, with an average rate of 30%. The combination of selective salpingography with fallopian tube recanalization has improved the overall management of infertility caused by tubal obstruction. The same catheterization technique used in fallopian tube recanalization is currently being explored for use in tubal sterilization.

Catheterization↗