Individualized, chemically pristine single-walled carbon nanotubes have been intravenously administered to rabbits and monitored through their characteristic near-infrared fluorescence. Spectra indicated that blood proteins displaced the nanotube coating of synthetic surfactant molecules within seconds. The nanotube concentration in the blood serum decreased exponentially with a half-life of 1.0 ؎ 0.1 h. No adverse effects from low-level nanotube exposure could be detected from behavior or pathological examination. At 24 h after i.v. administration, significant concentrations of nanotubes were found only in the liver. These results demonstrate that debundled single-walled carbon nanotubes are highcontrast near-infrared fluorophores that can be sensitively and selectively tracked in mammalian tissues using optical methods. In addition, the absence of acute toxicity and promising circulation persistence suggest the potential of carbon nanotubes in future pharmaceutical applications.nanoparticle biodistribution ͉ nanoparticle toxicity ͉ luminescence spectroscopy ͉ single-walled carbon nanotubes S ingle-walled carbon nanotubes (SWNTs) are an important class of artificial nanomaterials with remarkable mechanical, thermal, electronic, and optical properties. These properties suggest diverse future biomedical uses in areas such as targeted chemotherapeutics, in vitro cell markers, diagnostic imaging contrast agents, biochemical sensors, and photoablative therapy agents (1-9). Before medical applications can be developed, it is necessary to explore the behavior and fate of SWNTs in mammals. However, little is currently known in this area, in part because of the challenge of detecting and tracking these allcarbon nanoparticles in complex biological environments.SWNTs can be envisioned as sections of graphene sheets rolled up to form seamless cylindrical tubes with a variety of structures (10). Each of these structures has a well defined diameter and chiral angle and shows either semiconducting or metallic behavior. The nanotube preparations used for this study contain several dozen structural types that are Ϸ1 nm in diameter and Ϸ300 nm long. After excitation with visible light, each type of semiconducting SWNT fluoresces at a near-infrared (near-IR) wavelength between Ϸ900 and 1,600 nm that is characteristic of its specific structure (11, 12). We have previously exploited this fluorescence emission to study the active ingestion of SWNTs by macrophage cells in vitro (13).Here we report the use of the intrinsic near-IR fluorescence, which is a property only of individualized SWNTs, to measure their blood elimination kinetics in rabbits and to identify the organs in which they concentrate. These methods and results provide a foundation for developing the targeted delivery of nanotubes to specific tissues for diagnostic and therapeutic uses. In contrast to alternative methods that track carbon nanotubes by linking them covalently or noncovalently to external fluorophores or chelated radioisotopes (1,8,14), the near-IR fluor...

The dyeing properties of cationic cotton dyed with acid dyes are examined in this study. For comparison, nylon 6 and untreated cotton are dyed by the same acid dyes (Sandolan Red MF‐2BL, Sandolan Golden Yellow MF‐GL, and Sandolan Blue MF‐GL). A cationic agent, polyepichlorohydrin‐dimethylamine (PECH‐amine), is used to modify cotton fabric. Significant increase in color yield is observed for cationic cotton over untreated cotton because of the introduced positively charged sites by cationic modification. Deeper shades are obtained in all cases with cationic cotton. All of the acid dyes used in this study show significant hooking behavior with both cationic cotton and nylon. © 2006 Wiley Periodicals, Inc. J Appl Polym Polym Sci 100: 3302–3306, 2006

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BackgroundNovel approaches to treat human cancer that are effective with minimal toxicity profiles are needed. We evaluated gold nanoparticles (GNPs) in human hepatocellular and pancreatic cancer cells to determine: 1) absence of intrinsic cytotoxicity of the GNPs and 2) external radiofrequency (RF) field-induced heating of intracellular GNPs to produce thermal destruction of malignant cells. GNPs (5 nm diameter) were added to 2 human cancer cell lines (Panc-1, Hep3B). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and propidium iodide-fluorescence associated cell sorting (PI-FACS) assessed cell proliferation and GNP-related cytotoxicity. Other GNP-treated cells were exposed to a 13.56 MHz RF field for 1, 2, or 5 minutes, and then incubated for 24 hours. PI-FACS measured RF-induced cytotoxicity.ResultsGNPs had no impact on cellular proliferation by MTT assay. PI-FACS confirmed that GNPs alone produced no cytotoxicity. A GNP dose-dependent RF-induced cytotoxicity was observed. For Hep3B cells treated with a 67 μM/L dose of GNPs, cytotoxicity at 1, 2 and 5 minutes of RF was 99.0%, 98.5%, and 99.8%. For Panc-1 cells treated at the 67 μM/L dose, cytotoxicity at 1, 2, and 5 minutes of RF was 98.5%, 98.7%, and 96.5%. Lower doses of GNPs were associated with significantly lower rates of RF-induced thermal cytotoxicity for each cell line (P < 0.01). Cells not treated with GNPs but treated with RF for identical time-points had less cytotoxicity (Hep3B: 17.6%, 21%, and 75%; Panc-1: 15.3%, 26.4%, and 39.8%, all P < 0.01).ConclusionWe demonstrate that GNPs 1) have no intrinsic cytotoxicity or anti-proliferative effects in two human cancer cell lines in vitro and 2) GNPs release heat in a focused external RF field. This RF-induced heat release is lethal to cancer cells bearing intracellular GNPs in vitro.

Nosocomial pneumonia in trauma patients is a significant source of resource utilization and mortality. We have previously described increased rates of pneumonia in male trauma patients in a single institution study. In that study, female trauma patients had a lower incidence of postinjury pneumonia but a higher relative risk for mortality when they did develop pneumonia. We sought to investigate the hypothesis that male trauma patients have an increased incidence of postinjury pneumonia in a separate population-based dataset. Prospective data were collected on 30,288 trauma patients (26,231 blunt injuries, 4057 penetrating injuries) admitted to all trauma centers (n = 26) in Pennsylvania over 24 months (January 1996 to December 1997). Gender differences in pneumonia were determined for the entire dataset. A second analysis examined all blunt injury patients and excluded all patients with a hospital length of stay less than 24 h, eliminating patients who expired early after admission. In trauma patients with minor injury (ISS < 15), there was no significant difference between male and female patients in the rate of postinjury pneumonia (male 1.37%, female 1.11%). In the moderate-injury group (ISS > 15), male trauma patients had a significantly increased incidence of postinjury pneumonia (ISS 15-30, male 8.85%, female 6.45%; ISS > 30, male 24.35%, female 17.30%). Logistic regression analysis of blunt trauma patients revealed that gender, ISS, injury type, admission Revised Trauma Score (RTS), admission respiratory rate, history of cardiac disease, and history of cancer were all independent predictors of pneumonia. Trauma patients with nosocomial pneumonia had a significantly higher mortality rate (P < 0.001) than patients without pneumonia. There was no gender-specific difference in mortality among pneumonia patients. Male gender is significantly associated with an increased incidence of postinjury pneumonia. In contrast to our initial study, there was no gender difference in postinjury pneumonia mortality rates identified in this population-based study.

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The complication rates for pelvic exenteration remain high, but the morbidity can typically be managed without a clinically important increase in hospitalization. In primary LARC, an aggressive surgical approach provides most patients 5-year DFS. Select patients with recurrent LARC will also benefit from pelvic exenteration.