Back to the future for wound care?

The European Renaissance was a time of enormous change and rapid progress in the arts, sciences, and medicine. A glimpse of wound care in the last phase of the European Renaissance is provided by the analysis of work by Wilhelm Fabry, the "father of German surgery," as provided in his book De Combustionibus ("Burns") which details his range of treatments for the burn wound, as well as his approach to the later problems of scarring and contracture. We describe some of the historic events which may have stimulated Fabry's writings, in particular, the influences passed down from the medical school of Padua which thereby advanced the cause of wound care and surgery. Finally, we briefly explore the potential of such an approach to the works of our medical forefathers.     

In vitro studies of intragastric digestion

Following consumption of a meal, 99% of the large food particles are emptied only after intragastric fragmentation has reduced their diameter to less than 2 mm. Anin vitro model was constructed to evaluate some of the factors which may play a role in the process of intragastric digestion. Gastric mixing of food was simulated in a silicone rubber tube (ID 19 mm) placed in a peristaltic pump. Peristaltic waves progressed upwards along the tube at a frequency of 0, 1, or 3/min, reducing the internal diameter of the tube to 5 mm. Cooked chicken liver particles (2–2.8 mm in diameter) were placed in the tube with one of the following: (1) 150 mM NaCl, (2) 150 mM HCl with or without pepsin, or (3) phosphate buffer at pH 7, 5.4, or 2.6 + pepsin. After 30 min, the extent of particle reduction and of solubilization of proteins were determined and expressed as percent of the initial liver weight. The diameter of liver particles was reduced to a greater extent in NaCl than in pH 7 buffer or acid solutions with or without pepsin. In contrast, the amount of proteins solubilized was enhanced two- to threefold by acid pepsin solutions compared to NaCl or pH 7 phosphate. The presentin vitro studies suggest that changes in motor and/or secretory activity of the stomach significantly modify intragastric digestion.     

Kinds and locations of mutations arising spontaneously in the coding region of theHPRT gene of finite-life-span diploid human fibroblasts

Spontaneous thioguanine-resistant mutants were derived from populations of finite-life-span, diploid human fibroblasts by means of a fluctuation analysis. cDNA was prepared from mutantHPRT mRNA and amplified by the polymerase chain reaction, and the sequence of the product was analyzed. Exon deletions, which very likely arose from mutations in the intron splice site consensus sequences, were found in 10 of the 37 mutants examined (27% of the total). Among the 28 mutations in the coding sequence, base pair substitutions predominated (89%). With the exception of one base pair involved in a tandem mutation, all base pair substitutions resulted in alterations in the predicted amino acid sequence of the protein. In addition there were three frameshift mutations, consisting of the deletion of one or two base pairs. Although mutations occurred throughout the coding sequence, 50% (14/28) were found in the 5 portion of exon 3.     

Characterization of rat hyperplastic bile ductular epithelial cells in culture andin vivo

A novel intrahepatic biliary cell culture/in vivo transplantation system has been developed with an essentially pure population of bile ductular epithelial cells isolated from rat liver 6–12 weeks after bile duct ligation. In primary culture, these cells retain staining strongly for -glutamyltranspeptidase and glutathione S-transferase P. The cytoplasm of cultured bile ductular cells reacts with an anti-laminin antibody, but loses immunoreactivity with a monoclonal anti-cytokeratin 19 antibody. Semiconservative DNA synthesis in the cultured cells was dependent upon the continued presence of 10% fetal calf serum in the medium. Replicating bile ductular cells could be subcultured for a finite number of passages. In addition, freshly isolated bile ductular epithelial cells gave rise to well differentiated bile ductular structures when transplanted into the interscapular fat pads of syngeneic recipient rats.Presented at the Proceedings of the International Meeting on Normal and Neoplastic Growth in Hepatology, Bari, Italy, June 1989.This work was supported by USPHS Grant RO1 CA39225 to Dr. Sirica by the National Cancer Institute, Department of Health and Human Services.     

A Phase II trial of flavopiridol (NSC #649890) in patients with previously untreated metastatic androgen-independent prostate cancer.

PURPOSE: Flavopiridol is a cyclin-dependent kinase inhibitor with preclinical activity against prostate cancer cell lines. A Phase II trial was conducted to determine the activity of flavopiridol in patients with metastatic hormone-refractory prostate cancer. EXPERIMENTAL DESIGN: A total of 36 patients was enrolled from several institutions and treated with a 72-h continuous infusion of flavopiridol every 14 days at the eventual starting dose of 40 mg/m(2)/day. Dose escalation up to 60 mg/m(2)/day was permitted if no significant toxicity was observed. Responses were assessed every 12 weeks. Only those patients completing four courses of the 72-h infusion were considered evaluable for response because the primary objective was to determine progression-free survival at 6 months given the cytostatic nature of the agent. RESULTS: This study was conducted in a two-stage fashion. During the first stage, at least 20 evaluable patients needed to be enrolled to assess response. There were 22 of 36 patients evaluable for response. No objective responses were observed. Only 4 patients had stable disease for 16, 26, 29, and 48 weeks, respectively, stopping the trial by design as only 3 of 22 (14%) of the patients met the 6-month progression-free survival end point. The most common toxicities were diarrhea (grade 1 and 2) and nausea, although some grade 3 and 4 diarrhea (11 and 6%, respectively) were evident. CONCLUSIONS: Flavopiridol has disappointing single-agent activity in hormone-refractory prostate cancer when administered at this dose and schedule. Its use in prostate cancer should be reserved for evaluation in combination therapies or alternative schedules.     

Phase II study of 1alpha-hydroxyvitamin D(2) in the treatment of advanced androgen-independent prostate cancer.

PURPOSE: In this single institution Phase II trial, we evaluated the efficacy of the vitamin D analogue, 1alpha-OH-D(2), in patients with advanced hormone-refractory prostate cancer. Experimental Design: The patients initially received 1alpha-OH-D(2) at 12.5 micro g p.o. every day, which was dose adjusted for hypercalcemia. Given the cytostatic nature of the drug, the primary study end point was progression-free survival for a minimum of 6 months. The secondary end point was further characterization of drug toxicity. RESULTS: A total of 26 patients was enrolled. Using the intent-to-treat population, stable disease was seen for an average of 19.2 weeks (median 12 weeks, range 3-108 weeks). Twenty patients were evaluable for response. The one patient that achieved disease stabilization for >2 years elected to come off-study because of patient preference. His last disease evaluation showed no evidence of progression. No objective responses were seen. Previous and ongoing clinical observations strongly imply that PSA could be a misleading surrogate marker for clinical effect with this type of drug. Therefore, prostate-specific antigen was not used as a marker for disease response. Toxicity was as expected with mild hypercalcemia and associated symptoms like constipation and prerenal azotemia seen in some patients. Six (30%) evaluable patients experienced stable disease for >6 months, suggesting possible cytostatic activity. CONCLUSION: The results of this and other trials suggest further clinical investigation in this disease with vitamin D analogues alone or in combination with other agents, such as chemotherapy, should be pursued.     

Stretch injury causes calpain and caspase-3 activation and necrotic and apoptotic cell death in septo-hippocampal cell cultures

Traumatic brain injury (TBI) results in numerous central and systemic responses that complicate interpretation of the effects of the primary mechanical trauma. For this reason, several in vitro models of mechanical cell injury have recently been developed that allow more precise control over intra- and extracellular environments than is possible in vivo. Although we recently reported that calpain and caspase-3 proteases are activated after TBI in rats, the role of calpain and/or caspase-3 has not been examined in any in vitro model of mechanical cell injury. In this investigation, varying magnitudes of rapid mechanical cell stretch were used to examine processing of the cytoskeletal protein alpha-spectrin (280 kDa) to a signature 145-kDa fragment by calpain and to the apoptotic-linked 120-kDa fragment by caspase-3 in septo-hippocampal cell cultures. Additionally, effects of stretch injury on cell viability and morphology were assayed. One hour after injury, maximal release of cytosolic lactate dehydrogenase and nuclear propidium iodide uptake were associated with peak accumulations of the calpain-specific 145-kDa fragment to alpha-spectrin at each injury level. The acute period of calpain activation (1-6 h) was associated with subpopulations of nuclear morphological alterations that appeared necrotic (hyperchromatism) or apoptotic (condensed, shrunken nuclei). In contrast, caspase-3 processing of alpha-spectrin to the apoptotic-linked 120-kDa fragment was only detected 24 h after moderate, but not mild or severe injury. The period of caspase-3 activation was predominantly associated with nuclear shrinkage, fragmentation, and apoptotic body formation characteristic of apoptosis. Results of this study indicate that rapid mechanical stretch injury to septo-hippocampal cell cultures replicates several important biochemical and morphological alterations commonly observed in vivo brain injury, although important differences were also noted.     

Phenotypic diversity in siblings with partial androgen insensitivity syndrome

The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.     

The procoagulant activity of red blood cells from patients with severe preeclampsia

OBJECTIVE: Our purpose was to determine whether red blood cells from patients with severe preeclampsia may exhibit increased membrane exposure of procoagulant phospholipids (i.e., phosphatidylserine), which may initiate intravascular clotting and platelet activation. STUDY DESIGN: The study group comprised 28 women: 9 with severe preeclampsia in the third trimester of pregnancy, 10 normotensive with uncomplicated pregnancies, and 9 age-matched, nonpregnant, healthy women. The exposure of phosphatidylserine on the outer membrane phospholipid layer was analyzed with use of isolated, washed red blood cells that were added as a source of phospholipids to a “prothrombinase” coagulation complex. RESULTS: The resultant thrombin formed was measured by an amidolytic assay. Thrombin generation significantly increased on the addition of red blood cells from women with preeclampsia (741 ± 132 mU/ml/min) compared with red blood cells from normotensive pregnant (422 ± 228 mU/ml/min) and nonpregnant women (316 ± 268 mU/ml/min, p = 0.0008). CONCLUSION: This study indicates that in patients with preeclampsia the red blood cells exhibit a significant procoagulant surface that may trigger thrombin formation, thereby playing a role in the hypercoagulable state.(Am J Obstet Gynecol 1997;177:6)