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Biomedical subjects

Michael Groves

Publications and source records attributed to Michael Groves.

4 recordsLinked to original sources

Predicting erythroid response to recombinant erythropoietin plus granulocyte colony-stimulating factor therapy following a single subcutaneous bolus in patients with myelodysplasia.

We randomized 21 patients with low-risk myelodysplastic syndromes (MDS) to receive a single subcutaneous bolus of recombinant erythropoietin (epoietin) +/- granulocyte-colony stimulating factor (G-CSF), or placebo and monitored erythropoietic response over 7 days. In this small study, the reticulocyte response at day 7 was highly predictive of subsequent response to a therapeutic trial of epoietin + G-CSF.

Drug Administration Schedule↗

Managing medication errors--a qualitative study.

Medication errors continue to be a significant issue affecting patient safety in United States hospitals. The researchers conducted a qualitative study to explore the understanding and management of medication errors by practicing nurses. The results indicated a belief that late medication administration does not always constitute an error, the use of nursing judgment helps determine when and if medication should be given, and an increased reliance upon computerized and systematic checks put into place in health care systems.

Attitude of Health Personnel↗

Mitochondrial dysfunction associated with neuronal death following status epilepticus in rat.

Status epilepticus (SE) in humans and animal models results in significant cerebral damage and an increased risk of subsequent seizures, associated with a characteristic pattern of neuronal loss particularly affecting the hippocampus. Seizure related cell death is considered to be excitotoxic, but studies have been limited, concentrating on terminal events rather than initial mechanisms. We have studied the biochemical events in the first few days following SE. Self-sustaining limbic SE was induced in adult rats using perforant path stimulation, and animals were allowed to recover. Biochemical studies were performed at 16, 44 h and 8 days following SE, using spectrophotometric enzyme assays and HPLC on regional brain homogenates compared with those from sham-operated controls. Haematoxylin and eosin histology was also undertaken at each time point. Brain aconitase and alpha-ketoglutarate dehydrogenase (alphaKDH) activity were both significantly (P<0.05) reduced by approximately 20% in the first 16-44 h following status, but had returned to normal by 8 days. These enzymes are part of the tri-carboxylic acid (Krebbs) cycle in the mitochondrial matrix, and are known to be sensitive to free radical, especially peroxynitrite damage. There was a similar decrease in reduced glutathione levels. Histological studies confirmed evidence of acute neuronal damage up to 44 h, and neuronal loss by 8 days. This is the first in vivo demonstration of this pattern of mitochondrial dysfunction and loss of brain glutathione following SE. The pattern of abnormalities is consistent with reversible mechanisms being involved in excitotoxic cell damage. This, together with the timing of changes, suggests new avenues for therapeutic intervention.

Animals↗

Detection of infectious agents in brain of patients with acute hemorrhagic leukoencephalitis.

Acute hemorrhagic leukoencephalitis (AHL) is a rare and usually fatal disorder characterized clinically by an acute onset of neurologic abnormalities. It may occur in association with a viral illness or vaccination. Radiology and brain biopsy are essential for the diagnosis. The etiology of AHL is unclear. We postulated that viral/bacterial infection might be responsible, directly or through an immune-mediated mechanism, for this acute inflammatory myelinopathy. Fifteen cases of AHL were studied. Infectious agents, including varicella zoster virus (VZV), herpes simplex virus (HSV), human herpes virus-6 (HHV-6), cytomegalovirus, Epstein-Barr virus, and Mycoplasma, were investigated in brain specimens using the polymerase chain reaction (PCR), reverse transcriptase (RT)-PCR, and immunohistochemistry. Using PCR, HSV DNA was found in four cases, VZV DNA in two, and HHV-6 DNA in one. Among the control cases, two were HSV DNA positive. Further investigation to detect HSV RNA and antigens in HSV DNA-positive cases revealed that two cases with AHL were both HSV RNA and antigen positive. AHL is a hyperacute disease, which is considered the most acute form of acute disseminated encephalomyelitis (ADEM). Our findings suggests that a viral infection may be implicated in its pathogenesis, most likely through an indirect mechanism; however, as only a few cases of this rare disease were examined, statistical significance was not achieved. As a number of patients with disorders of the ADEM group may progress to develop multiple sclerosis (MS), we argue that an organism that has produced the former may remain in the brain tissue and be subsequently involved in the production of a self-sustained disorder such as MS.

Acute Disease↗