Microfabricated microneedles: a novel approach to transdermal drug delivery

Although modern biotechnology has produced extremely sophisticated and potent drugs, many of these compounds cannot be effectively delivered using current drug delivery techniques (e.g., pills and injections). Transdermal delivery is an attractive alternative, but it is limited by the extremely low permeability of skin. Because the primary barrier to transport is located in the upper 10-15 micron of skin and nerves are found only in deeper tissue, we used a reactive ion etching microfabrication technique to make arrays of microneedles long enough to cross the permeability barrier but not so long that they stimulate nerves, thereby potentially causing no pain. These microneedle arrays could be easily inserted into skin without breaking and were shown to increase permeability of human skin in vitro to a model drug, calcein, by up to 4 orders of magnitude. Limited tests on human subjects indicated that microneedles were reported as painless. This paper describes the first published study on the use of microfabricated microneedles to enhance drug delivery across skin.     

Circumstances of falls causing hip fractures in the elderly

A prospective analysis was performed on 832 patients to determine the circumstances surrounding falls leading to hip fracture within a homogeneous, elderly urban population. Special emphasis was placed on the season of year, time of day, location of fall, and other circumstances in which the fracture occurred. All patients were community dwelling, cognitively intact, previously ambulatory elderly who sustained a femoral neck or intertrochanteric fracture. Most fractures occurred at home, particularly in patients who were older, less healthy, and poorer ambulators. More than 75% of fractures resulted from a fall while the patient was standing or walking. Most falls occurred during daylight hours with a peak seen in the afternoon. No seasonal variation in the incidence of hip fractures was observed.     

Regulation of transforming growth factor-beta type II receptor expression in human breast cancer MCF-7 cells by vitamin D3 and its analogues

In view of the tumor suppressor role of the transforming growth factor-beta (TGFbeta) type II receptor (RII), the identification and characterization of agents that can induce the expression of this receptor are of potential importance to the development of chemoprevention approaches as well as treatment of cancer. To date, the identification of exogenous agents that control RII expression has been rare. We demonstrated that proliferation of MCF-7 early passage cells (MCF-7 E), which express RII and are sensitive to TGFbeta growth inhibition activity, was significantly inhibited by vitamin D3 and its analogue EB1089. In contrast, proliferation of MCF-7 late passage cells (MCF-7 L), which have lost cell surface RII and are resistant to TGFbeta, was not affected by these two compounds. TGFbeta-neutralizing antibody was able to block the inhibitory effect on MCF-7 E cells by these compounds, indicating that treatment induced autocrine-negative TGFbeta activity. An RNase protection assay showed approximately a 3-fold induction of the RII mRNA, while a receptor cross-linking assay revealed a 3-4-fold induction of the RII protein. In contrast, there was no change in either RII mRNA or protein in the MCF-7 L cells.     

Species-specific and ubiquitous-DNA-based assays for rapid identification of Staphylococcus aureus

A monoclonal antibody (mAb; a mouse IgM referred to as 1CF11) recognizing various human glycoproteins was obtained. While the immunoreaction of glycoproteins from human secretions including milk, saliva, and bronchus was demonstrated as a typical dose-responded S-shaped reaction curve on ELISA, no reaction was detected with milks and sera of animal origin as well as human serum. In the constituting polypeptides of the human milk secretory IgA molecule, only the secretory component was recognized by this mAb. Among various chemical treatments of the purified human milk lactoferrin (Lf), only either periodate or mild alkaline treatment abolished the immunoreactivity of the glycoprotein. A recombinant human Lf was not immunoreactive. Finally, the immunoreactive fragments were isolated from human milk Lf, which remained reactive with PAS reagent while lacking the previously reported N-glycans. These results strongly suggest that the mAb 1CF11 recognizes a new glycan O-glycosidically linked to glycoproteins in human secretions.     

Enhancement of doxorubicin content by the antitumor drug lonidamine in resistant Ehrlich ascites tumor cells through modulation of energy metabolism

The effect of the antitumor drug lonidamine (LND) on respiration, aerobic glycolysis, adenylate pool, doxorubicin (DOX) uptake, and efflux in DOX-resistant and DOX-sensitive Ehrlich tumor cells was investigated. The results may be summarized as follows: 1) In both types of cells, LND inhibited both respiration and glycolysis in a dose-dependent manner and lowered the ATP concentration. The effect was more marked in cells incubated in glucose-free medium; 2) LND raised, to a remarkable extent, the intracellular content of DOX in resistant and sensitive cells respiring on endogenous substrates because of reduced ATP availability, whereas in glucose-supplemented medium, where both respiration and glycolysis contributed to ATP synthesis, the increase was lower; and 3) when LND was added to DOX-loaded cells, it failed to significantly inhibit DOX efflux because of time-dependent phenomena. These findings indicated that LND, a drug currently employed in tumor therapy, might also be useful in reducing or overcoming multidrug resistance (MDR) of those cells with a reduced ability to accumulate and retain antitumor drugs.     

The role of the psychologist in crisis/hostage negotiations

The recruitment of antigen-specific lymphocytes at liver site represents a prominent feature in patients chronically infected with hepatitis C virus (HCV). However, despite the strong and multispecific response, chronic infection leads in a significant number of cases to the development of cirrhosis and hepatocellular carcinoma. The finding that the expression of CD80 structure positively correlates with disease histological worsening points out a role for the costimulatory pathway in the progression of liver cell injury. On the other hand, the demonstration of CD95 and CD95-ligand positive cells in the context of periportal areas, a pattern which is not strictly associated to HCV tissue distribution, indicates the occurrence of either virus-infected or innocent bystander hepatocyte killing. Nonetheless, the persistence of HCV, in spite of cytotoxic T lymphocyte (CTL) liver recruitment, suggests a possible in-situ imbalance of cytotoxic activities, above all referred to perforin-granzyme-dependent necrosis. Altogether, these findings outline that several factors might be involved in HCV-driven immunopathogenesis. Therefore, the fully clarification of these mechanisms may offer a suitable therapeutical approach for the improvement of clinical outcome in chronic hepatitis C.     

Single-specimen bile cytology: a prospective study of 80 patients with obstructive jaundice

The interaction between drugs (tolbutamide (1), 1-butyl-3-(methylsulfonyl)urea (2)) and human serum albumin (3) was investigated by equilibrium dialysis and NMR spectroscopy. The binding of 1 and 2 to 3 was concluded to be hydrophobic and hydrophilic, respectively, on the basis of the dependence of the binding constants on temperature, ionic strength, and chain length of fatty acid added. In 1H-NMR spectra of 1, there were no significant shifts with change in concentration or addition of 3. The spin-lattice relaxation time (T1) and spin-spin relaxation rate (1/T2) of the respective protons of 1 were independent of concentration, but depended on the concentration of 3 added. The binding position was determined from the ratio of 1/T2 of 1 bound to 3 and free 1. 1 and 2 were found to bind to 3 through the tolyl group and sulfonylurea group, respectively. The binding property of 1 was considered to be governed by the competition between the hydrophobic effect of the tolyl group and the hydrophilic effect of the sulfonylurea group in the molecule.