A gelatin in situ-overlay technique localizes brain matrix metalloproteinase activity in experimental focal cerebral ischemia.

To determine the activity of matrix metalloproteinases (MMP), especially MMP-2 and MMP-9, which play an important role in ischemic stroke and intracerebral hemorrhage, we adapted a simple and rapid method for localizing gelatinase activity to a gelatin film in situ-overlay technique previously used in cancer research. Ten micrometer cryosections of rat brain from controls and animals subjected to 3 h of ischemia and 48 h of reperfusion (suture model for transient cerebral ischemia) were used. After thawing, a gelatin film with a polyester base was put on the slide, incubated for 24 h at 37 degrees C, stained with Ponceau S, and then discolored in bi-distilled water. Non-staining areas on the film corresponded to lysis zones, caused by activated MMPs. This was proven by MMP incubation at various concentrations on the plain gelatin film and pretreatment with EDTA (an MMP inhibitor), which prevents lysis zones in normal and ischemic brains. As confirmatory tests, SDS-PAGE zymography was used to define MMP activity, and also MMP-2 immunohistochemistry to detect the possibly cellular origin of MMPs. Normal rat brain exhibited a low background activity, which was visible as a light halo-like lysis zone over and around the brain. Areas in normal brain with medium MMP activity were within the white matter (corpus callosum, anterior commissure, and cerebellum). Ischemic brain exhibited high activity lysis zones within the infarcted area (detected by microtubuli associated protein-2 staining). These zones consisted of microscopically small lysis holes with a diameter of about 10-20 microm. Immunohistochemistry showed that especially microvessels expressed MMP antigen. SDS-PAGE zymography differentiated between a high level of activated MMPs in the ischemic area and a low level in the non-ischemic basal ganglia. The gelatin film in situ-overlay technique is able to localize MMP activity in ischemic rat brain tissue on a microscopic level.

Home care nursing for persons with congestive heart failure: description and relationship to hospital readmission.

Although home care nursing has been associated with a lower rate of repeated hospitalization of persons with congestive heart failure, little is known about this relation. This study examined variables that reflect information about demographic characteristics, clinical status, nursing services, and repeated hospitalization for persons admitted with a primary diagnosis of congestive heart failure to one home care agency during one fiscal year. Implications related to assessment, documentation, patient instruction, and further research are discussed.

An ethnographic study of the process of medication discharge education (MDE).

(MDE) Medication discharge education (MDE) is an essential component of the hospital discharge process. It is especially important for older persons with heart disease because they are among the highest users of hospital care. Accurate management of medications is believed to be one strategy to prevent or delay hospitalization. Despite its accepted importance, there is little documented research about patient education in general, or MDE in particular. This ethnographic study collected interview, observational, and document data from older persons with heart disease, family members, nurses and medical records in order to describe the process of MDE. MDE was found to be both structured and unstructured, uncoordinated, and driven by accreditation guidelines. Older patients and their family members valued MDE, especially when information was personalized, provided orally and reinforced in writing. Suggestions for improving the effectiveness of MDE are offered.

L-arginine-induced regional cerebral blood flow increase is abolished after transient focal cerebral ischemia in the rat.

We investigated the L-arginine-induced, regional cerebral blood flow (rCBF) enhancement after different durations of transient focal cerebral ischemia in the rat to determine if L-arginine increases rCBF after transient focal cerebral ischemia. Focal ischemia (5 minutes and 20 minutes) followed by 90 minutes of reperfusion was induced in a normotensive rat suture-model. Regional cerebral blood flow in both hemispheres was measured by laser-Doppler-flowmetry. Reactivity of rCBF to L-arginine (300 mg/kg) was measured 45 minutes after reperfusion, and hypercapnia 90 minutes after reperfusion. The effect of D-arginine and pretreatment with the nitric oxide (NO) synthase inhibitor N(omega)-nitro-L-arginine (L-NA) (10 mg/kg) was examined in additional groups. Hypercapnia and L-arginine increased rCBF in sham operated controls and on the nonischemic hemispheres. D-arginine did not. Twenty-minute long ischemia significantly reduced the response to L-arginine (control side: 115 +/- 5.9%; ischemic side: 107 +/- 6.1%, n = 7) and hypercapnia, 5 minutes of ischemia did not. N(omega)-nitro-L-arginine pretreatment partly restored the L-arginine-induced rCBF increase. Thus, rCBF increase caused by L-arginine in the reperfusion period was unaffected by 5 minutes of ischemia, but reduced by 20 minutes of ischemia. The restoration after pretreatment with L-NA may be caused by attenuated production of cytotoxic substances, e.g., NO and related compounds.

A study of the relationship between home care services and hospital readmission of patients with congestive heart failure.

Patients with congestive heart failure (CHF) constitute a substantial portion of the caseloads of home care agencies. Home care is one strategy suggested for delaying or preventing hospital readmissions. This study examined the relationship between home care nursing services and hospital readmissions after 1176 discharges of patients with a primary diagnosis of CHF. It also described the home nursing care of such patients. Findings indicate that patients receiving home care nursing services were readmitted to the hospital significantly less often within a period of 90 days after hospital discharge.