Is a single day patient friendly methyl aminolevulinate photodynamic therapy illumination scheme for superficial basal cell carcinoma feasible? A randomized multicenter pilot trial

BACKGROUND

Topical methyl aminolevulinate photodynamic therapy (MAL-PDT) is highly effective for the treatment of superficial basal cell carcinoma (sBCC). Current European treatment protocol requires two hospital visits, which is costly and unpractical. The aim of this study was to evaluate the efficacy of fractionated MAL-PDT, using two light fractions at 3 and 4 h compared to illumination at 3 and 5 h after MAL-application.

METHODS

Thirty patients were randomized into two groups. The first group received illumination at 3 and 4 h (20 + 55 J/cm²) after MAL-application (3/4 group). In the other group, two light fractions were performed at 3 and 5 h (20 + 55 J/cm²) after MAL-application (3/5 group). The lesion response was evaluated at 3 and 12 months posttreatment.

RESULTS

In the 3/5 group, 70.0% showed a complete response (CR) at 3 months compared to 63.6% in the other group. At 12 months, 100% showed a CR in the 3/5 group compared to 80.0% in the other group. However, most failures/recurrences were eventually due to the presence of a more aggressive BCC subtype, mostly caused by sampling error of the primary punch biopsy.

CONCLUSION

Single day protocol for MAL-PDT for sBCC is feasible and this study shows promising results.

Reflectance confocal microscopy: non-invasive distinction between actinic keratosis and squamous cell carcinoma

BACKGROUND

Early recognition of squamous cell carcinoma (SCC) is difficult. Non-invasive reflectance confocal microscopic (RCM) imaging of the skin is a promising diagnostic technique. Although several RCM features for SCC and AK have been described, it is not determined whether RCM has the ability to distinguish between SCC and actinic keratosis (AK).

OBJECTIVE

To determine in vivo reflectance confocal microscopic features that are specific for making a distinction between AK and SCC.

METHODS

In 24 patients, 30 lesions clinically suspicious for AK or SCC were selected for RCM imaging. Following the imaging procedure, a 3 mm skin biopsy was obtained for confirmation of the histopathological diagnosis. Two observers evaluated the RCM images according to a literature based list of RCM features. The obtained data were evaluated by an univariate and forward multivariate logistic regression analysis, kappa analysis and independent T-test.

RESULTS

The univariate logistic regression showed statistically significant odds ratios for several RCM features, including architectural disarray in the stratum granulosum, architectural disarray in the spinous layer and nest-like structures in the dermis. The forward multivariate logistic regression analysis showed that the combination of these features increased the ability to make the correct diagnosis AK and SCC non-invasively. The interobserver agreement between a starting and an experienced RCM observer ranged from poor to no agreement.

CONCLUSION

This study revealed specific RCM features that can distinguish between AK and SCC, stimulating further prospective, large cohort research in this field. This will result in correct, efficient and adequate diagnosis and treatment of clinically difficult to distinguish AK and SCC lesions.

Breast cancer survival and in vitro tumor response in the extreme drug resistance assay

PURPOSE

To determine whether in vitro extreme drug resistance (EDR) assay results for patients with breast carcinoma were associated with clinical outcome after chemotherapy.

PATIENTS AND METHODS

EDR assays were performed on tumor tissue obtained from 103 newly diagnosed breast cancer cases. EDR scores of 2 for low, 1 for intermediate, or 0 for extreme drug resistance were determined for each agent tested. In vitro EDR scores for 4-hydroxycyclophosphamide (4HC) and doxorubicin were summed for patients treated with AC, or for 4HC and 5-FU for patients treated with CMF. Treatment selection was blinded to assay results.

RESULTS

Median time to progression was significantly shorter for patients with extreme or intermediate in vitro resistance (n = 55, 48 months), compared to patients with low in vitro resistance, (n = 41, 100 months, p = 0.022). Patients demonstrating extreme to intermediate drug resistance also showed poorer survival than the low resistance group (49.5 months vs. not reached, median follow-up 48 months, p =0.011). Summed EDR scores, stage, and number of lymph nodes were significantly associated with survival in univariate and multivariate analysis. Compared to EDR scores of 4, summed EDR scores of 0-1 and summed EDR scores of 2-3 were associated with a relative risk of death of 3.09 (95%, CI 1.05-9.06, Cox proportional hazards model, p = 0.040) and 2.35 (95%, CI 1.07-5.15, Cox proportional hazards model, p = 0.033), respectively.

CONCLUSION

Extreme drug resistance testing identified patients with individual patterns of drug resistance prior to therapy. In this cohort of breast cancer patients treated with chemotherapy, summed EDR scores were significantly associated with time to tumor progression and overall survival. EDR results may offer a method for optimizing treatment selection.

Expanded functions in the apical cell domain to regulate the growth rate of imaginal discs

The Drosophila expanded (ex) gene encodes a product (Ex) that shares homology with the Protein 4.1 family of proteins, many of which are enriched at specific lateral cell junctions and the apical cellular domain. Ex colocalizes with actin in the apical domain of imaginal disc epithelial cells, where it partially overlaps the distribution of phosphotyrosine (PY)-containing proteins. This suggests that Ex is present in or associated with adherens junctions. Genetic studies show that Ex is necessary for proper regulation of final cell number in adult wings and for the formation of eyes, distal leg, and distal antennal segments. We have generated mitotic clones that lack Ex using the twin spot technique, and demonstrated that the primary function of Ex is to regulate cell proliferation. Overexpressing Ex protein results in a decrease in final cell number in wings, suggesting a direct relationship between Ex function and proliferation rate.

Gene therapy of metastatic colon carcinoma: regression of multiple hepatic metastases by adenoviral expression of bacterial cytosine deaminase

Colon carcinoma accounts for 20% of deaths due to malignancies in the Western world. Once metastases occur, therapeutic options are limited, with an approximate 5-year survival of only 5%. To investigate the potential of new gene therapeutic approaches, a hepatic micrometastasis model of colon carcinoma in BALB/c mice was established. Inoculation of syngeneic MCA26 colon carcinoma cells into the spleens of 18- to 20-week-old mice resulted in the formation of multiple hepatic metastases. Selective transduction of developing hepatic metastases was demonstrated using a beta-galactosidase-expressing recombinant adenovirus. Cytosine deaminase (CD) can metabolize 5-fluorocytosine into the chemotherapeutic reagent 5-fluorouracil (5FU). The antitumoral potential of this suicide gene therapy approach was explored by systemic application of a recombinant replication-deficient adenovirus encoding for the bacterial CD gene under the control of the cytomegalovirus promoter (Ad.CMV-CD). Injection into the tail vein of tumor-bearing mice resulted in delayed tumor growth with significant reduction in hepatic metastases. The potential of this experimental approach for possible future clinical applications was evaluated by investigating adenoviral transduction efficiency, 5FU sensitivity, and 5-fluorocytosine-dependent Ad.CMV-CD toxicity in a variety of human colon cancer cell lines. Although the murine cell lines MCA26 and CC36 were highly sensitive to 5FU, the human colon cancer cell lines showed a 1-100 times higher resistance to 5FU. Specific Ad.CMV-CD toxicity correlates with 5FU toxicity. Transduction efficiency in human colon carcinoma cell lines was shown to be 10-1700 times higher compared with murine cell lines, thus compensating for 5FU resistance. In conclusion, suicide gene therapy using CD may be promising as an adjuvant treatment regimen for hepatic micrometastases of human colon carcinoma.

Promoting cancer prevention activities among Vietnamese physicians in California

BACKGROUND

To promote prevention and early detection of cancer, the authors conducted a three-year intervention targeting Vietnamese physicians in solo practice in California.

METHODS

Twenty subjects who had received their medical training in Vietnam were recruited into a randomized controlled trial. The intervention included computerized or manual cancer screening reminders, continuing medical education seminars, Vietnamese-language health education materials, newsletters, and oncology data-query programs. Evaluation included chart audits for eight targeted activities pre- and post-intervention.

RESULTS

Before the intervention, annual physician performance rates were low for all eight activities: routine checkups (65.6%), Pap testing (13.8%), pelvic examinations (19.8%), clinical breast examinations (13.3%), mammography (6.4%), hepatitis B serologies (21.9%), hepatitis B immunizations (12.8%), and smoking cessation counseling (1.6%). After the intervention, performance rates increased significantly for smoking cessation counseling (p = 0.02), Pap testing (p = 0.004), and pelvic examinations (p = 0.01).

CONCLUSIONS

The results demonstrate the efficacy of an intervention targeting Vietnamese primary care physicians in promoting smoking cessation counseling, Pap testing, and pelvic examinations, but not other cancer prevention activities.

Hyperinnervation of the airways in transgenic mice overexpressing nerve growth factor

Neuropeptides released from sensory nerve endings are potential mediators of airway inflammation in asthma and lung injury induced by inhalation of respiratory irritants. To develop an in vivo model for assessing the contribution of neurogenic inflammation in these processes, we have generated transgenic mice with altered innervation of the lung. To generate mice with an increased innervation of the airways, we placed the gene that encodes nerve growth factor (NGF) under control of the lung-specific Clara-cell secretory protein (CCSP) promoter. Two lineages of CCSP-NGF transgenic mice overexpressed NGF in the lung and developed a hyperinnervation of the airways. Immunohistochemistry for substance P, a substance P enzyme immunoassay, and catecholamine histofluorescence indicated that both tachykinin-containing sensory fibers and sympathetic fibers were increased around the airways of CCSP-NGF mice. Treatment of CCSP-NGF mice with the sympathetic-specific neurotoxin 6-hydroxydopamine (6-OHDA) eliminated the sympathetic component of the airway innervation, leaving a specific hyperinnervation by tachykinin-containing sensory fibers. CCSP-NGF mice were more sensitive than normal mice to capsaicin-induced increases in respiratory system resistance, demonstrating that the increased sensory innervation led to a change in airway function. We conclude that NGF overexpression from a lung-specific promoter produces anatomic and functional changes in lung innervation, and that CCSP-NGF mice will be useful for studying the role of neurogenic inflammation in airway disease.

Design of potent dynorphin A-(1-9) analogues devoid of supraspinal motor effects in mice

Four analogues of dynorphin (Dyn) A-(1-9) incorporating D-Leu in position 8 alone or in combination with the nonhydrolysable psi [CS-NH] thiopeptide bond surrogate between positions 6 and 7 were tested in vitro for their ability to compete with the binding of selective kappa, mu, and delta opioid ligands, using membrane preparations of guinea pig cerebellum (kappa) and rat brain (mu and delta), for their ability to block the electrically induced contractions of the guinea pig ileum, and for their in vivo antinociceptive (writhing test) and motor (motor dysfunction assay) activities in mice. [D-Leu8]Dyn A-(1-9) displayed an affinity and a selectivity for the kappa opioid receptor that were comparable with those of Dyn A-(1-9). The potencies of [D-Leu8]Dyn A-(1-9) in the guinea pig ileum, writhing, and motor dysfunction assays were markedly enhanced (8-12 fold) compared with those of Dyn A-(1-9). [6 psi 7(CS-NH),D-Leu8]Dyn A-(1-9), [Lys6, 6 psi 7(CS-NH),D-Leu8] Dyn A-(1-9), and [Leu6, 6 psi 7(CS-NH), D-Leu8]Dyn A-(1-9) were somewhat less potent than [D-Leu8]Dyn A-(1-9) in all opioid assays. However, the thiopeptides were more potent analgesics than Dyn A-(1-9)(ED50 of 29.5, 23.9, and 15.5 nmol/mouse, respectively, compared with 90.7 nmol/mouse for Dyn A-(1-9)) and caused little or no motor impairment at analgesic doses.

Physical characterization of incense aerosols

Experiments were performed to study the physical characteristics of smoke aerosols generated by burning three types of stick incense in a 4 m3 clean room. Sidestream cigarette smoke was also examined under the same conditions to provide a comparison. Among the parameters measured were (a) masses of aerosol, carbon monoxide and nitrogen oxides generated by burning the incense or cigarettes, (b) rates of decay of the particles from the air, and (c) estimates of count median particle size during a 7 h period post-burning. There was variability among the types of incense studied with respect to many of the parameters. Also, as a general trend, the greater the initial particulate mass concentration, the more rapid the rate of decay of the smoke. In relation to the quantity of particulate generated, cigarette smoke was found to produce proportionally larger quantities of carbon monoxide and nitrogen oxides than did incense. Due to the fact that burning incense was found to generate large quantities of particulate (an average of greater than 45 mg/g burned, as opposed to about 10 mg/g burned for the cigarettes), it is likely, in cases in which incense is habitually burned in indoor settings, that such a practice would produce substantial airborne particulate concentrations.

Antiarrhythmic agent amiodarone possesses calcium channel blocker properties

Amiodarone possesses multiple pharmacologic properties, including peripheral and coronary vasodilatation, negative inotropy, and negative chronotropic and dromotropic effects. These properties are shared by the group of drugs termed calcium channel blockers. We examined the interaction of amiodarone with receptors for the 1,4-dihydropyridine (DHP) calcium blockers in rat and rabbit myocardial membrane particulates. Amiodarone displaced specifically bound [3H]nitrendipine in both rat and rabbit preparations in a competitive, concentration-dependent manner at a single class of binding sites (Ki approximately 0.27 micxroM). Calcium channel activity was determined pharmacologically in a tissue bath with electrically stimulated rabbit right ventricular strips, KCl-induced aortic ring contraction, and 45Ca2+ uptake in K(+)-depolarized cultured rat cardiomyocytes. Amiodarone completely inhibited myocardial contraction (EC50 = 1.7 microM), completely antagonized depolarization-induced aortic ring contraction (EC50 = 24 nM), and significantly reduced (29% vs. control) 45Ca2+ uptake into cultured cells. The calcium channel blocking effects of amiodarone may contribute significantly to its pharmacologic profile.

Endothelin increases the synthesis and secretion of atrial natriuretic peptide in neonatal rat cardiocytes

Endothelin (ET) effected a dose-dependent increment in atrial natriuretic peptide (ANP) secretion and ANP mRNA accumulation in neonatal rat atrial and ventricular cardiocytes but had no effect on the processing of the ANP prohormone to the mature ANP product. The secretagogue effect was not limited by cell density. Both basal and ET-dependent secretory activity were abrogated by the calmodulin antagonist calmidazolium but were unaffected by meclophenamate or pertussis toxin. The magnitude of the ET-dependent increment in ANP secretion was amplified by culturing the cells in a dynamically pulsating (vs. static) environment, implying an interaction between mechanical and agonist-mediated secretory stimuli in this system. ET also promoted immunoreactive ANP release from primary cultures of fetal rat hypothalamic cultures, suggesting that this regulatory function may be generally employed in ANP gene-expressing cells. These findings demonstrate that ET has parallel effects on ANP synthesis and secretion and support a role for this peptide in the regulation of local and circulating levels of the natriuretic hormone.

Coronary angioplasty in octogenarians: comparisons to coronary bypass surgery

Coronary angioplasty was performed in 74 patients 80 years of age and older (mean 83 +/- 3). Single vessel coronary disease was present in 34% and multivessel coronary disease in 66%. Angioplasty of a single vessel was performed in 51 patients (69%), while 23 (31%) had angioplasty of multiple vessels. Angioplasty was successful in 59 of 74 patients (80%). Angioplasty was unsuccessful but uncomplicated in 12 (16%) due to (unyielding) calcified lesions or (impassable) old occlusions. Of these 12, 8 were discharged on medical therapy and 4 underwent elective uncomplicated bypass surgery prior to discharge. Three (4%) patients required emergency coronary bypass surgery due to abrupt vessel closure during the angioplasty procedure, with one hospital death (1.4%). Follow-up (mean 24 +/- 22 months) was obtained in all patients. Of the 59 successful angioplasty patients, late mortality was 10% (cardiac 7% and non-cardiac 3%). Survival and survival without myocardial infarction were both 90%; survival without either infarction or bypass surgery was 86%. Actuarial 3-year survival was 91% and 3-year freedom from death, infarction or bypass surgery was 87% by life-table analysis. Repeat angioplasty for restenosis was performed in 7 patients (12%) without complications.

Production and differential endocrine regulation of atrial natriuretic peptide in neuron-enriched primary cultures

To identify factors that directly regulate the synthesis and secretion of atrial natriuretic peptide (ANP) in neuronal cells, we have developed a neuron-enriched primary culture system from fetal rat brains. A number of factors proved of importance in maintaining adequate levels of ANP secretion in such cultures: 1) cultures derived from diencephalon produced much more ANP than cultures derived from diencephalon produced with the distribution of ANP-containing cells in the rat brain; 2) brains from rats at gestational day 17 proved a better source of ANP-secreting cells than brains from rats at gestational day 16; 3) the presence of serum was required in the latter stages of the culture period to allow expression of the ANP gene; and 4) the cultures secreted more ANP when maintained at 39 C vs. 37 C. ANP mRNA transcripts in the neuron-enriched primary cultures were analyzed by S1 nuclease protection and shown to have a transcription start site similar to that employed by rat atrium and fetal hypothalamus in vivo. Dexamethasone and T3, in contrast to their stimulatory effect on ANP production in cardiocyte cultures, suppressed both the release of immunoreactive ANP and the levels of ANP mRNA in the neuron-enriched primary cultures. The cultures incorporated [35S]cysteine into immunoprecipitable ANP. HPLC analysis of 35S-labeled products in the medium revealed that, unlike neonatal cardiocyte cultures, the majority of secreted immunoreactive ANP migrated with the processed form(s) of ANP rather than the prohormone.

Does percutaneous transluminal coronary angioplasty accelerate atherosclerotic lesions?

Recent reports have suggested that angioplasty may cause or accelerate coronary arterial stenoses secondary to traumatic injury. Ninety-four coronary angiograms performed in a 1 yr period were reviewed in patients who had successful coronary angioplasty 6 to 30 mo (mean 10.7) prior to restudy. Restenosis was found in 43 of 140 dilated lesions (31%) and in 41 of 94 patients (44%). Thirty-three (35%) patients had new or progressive lesions outside the angioplasty site. New or progressive lesions occurred with similar frequency in the arteries that did not have angioplasty (23/155 = 15%) as in the arteries that did (13/127 = 10%; chi-square n.s.). In the arteries which underwent angioplasty, new or progressive lesions occurred as commonly proximal to the PTCA site (7/14, 50%) as distal (6/13, 46%). New or progressive lesions occurred in 29% of patients with concomitant restenosis, and 40% of those without restenosis (chi-square n.s.). No clinical, angiographic, or procedural factors distinguished patients with new and progressive lesions in target vessels from those without these lesions in target vessels. Patients with progressive lesions anywhere in the coronary tree were more likely to have had a shorter duration of anginal symptoms before angioplasty and a family history of coronary disease when compared with patients without progressive atherosclerosis. In conclusion, new and progressive lesions outside the angioplasty site occur after the procedure but appear unrelated to the restenosis process or traumatic injury by angioplasty instrumentation.

Hydrogen peroxide removal by the calf aqueous outflow pathway

Previous studies have shown that aqueous humor of calf and human eyes contains about 25 microM hydrogen peroxide. We have studied the removal of hydrogen peroxide by the outflow pathway of intact, freshly enucleated, calf eyes. Eyes were immersed under silicone oil that had a density greater than water and medium containing various agents was perfused into the anterior chamber. Medium passing through the trabecular meshwork and out the cut ends of the aqueous veins was trapped by the silicone oil and harvested. By measuring the concentration of hydrogen peroxide in the anterior chamber and in the emerging medium, we were able to study the rate of removal by the outflow structures and the effect of inhibitors on this rate. At 1 mM hydrogen peroxide, the amount emerging was undetectable by our methods. At 10 mM, the results were inconsistent, suggesting that tissue damage may have been occurring. At 5 mM, the concentration in the emerging medium was reduced 150-1000-fold, depending on time and conditions. This rate of removal could be reduced by 3-aminotriazole, reaching a maximum inhibition of about 50% at 80 mM. Addition of 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) to further inhibit removal did not yield reliable results unless the concentration of H2O2 was lowered below 5 mM. Using loss of lactate dehydrogenase activity as a measure of cell damage, we found a 30% drop in activity after perfusing with BCNU, diamide, and 3-aminotriazole, followed by 3 hr with 10 mM hydrogen peroxide.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrophysiologic study in the management of cardiac arrest survivors: a critical review

This review discusses the value and limitations of EPS in the management of cardiac arrest survivors. Uncertainties associated with EPS include a lack of consensus with respect to stimulation protocol, end points for VT suppression during drug testing, significance of induced polymorphic VT or VF, and timing of EPS after myocardial infarction. Despite methodologic shortcomings in most clinical studies, a useful body of knowledge has emerged. In cardiac arrest survivors, incidence of inducible sustained VT ranged from 35% to 75%. Where induced VT (sustained or nonsustained) was successfully suppressed, recurrent arrhythmic events occurred in 0% to 33% of patients over a 1- to 5-year follow-up period. Failed regimens correlated with a high risk of arrhythmic recurrence. EPS also helps to select patients for the implantable defibrillator or electrocardiac surgery. In conclusion, EPS appears empirically useful in the management of cardiac arrest survivors with coronary artery disease; its value in other disease entities is uncertain.

Glutathione reductase of calf trabecular meshwork

Hydrogen peroxide has been found in both calf and human aqueous humor at a level of 25 microM. It is likely, therefore, that trabecular meshwork possesses mechanisms for detoxifying H2O2, both to protect itself and other more distal structures of the outflow pathway from oxidative damage. We have recently demonstrated an active glutathione peroxidase in calf trabecular meshwork. In this study, we have characterized the complementary enzyme, glutathione reductase. The activity was present at a level of 0.120 units/min/g wet of tissue (0.005 units/min/mg soluble protein). The enzyme quickly lost activity in crude extracts but could be stabilized by heating at 60 degrees C for 30 min. Denatured protein was removed by centrifuging at 43,000 X g. Heating at 80 degrees C for 10 min destroyed all enzyme activity. Addition of 1 mM GSSG protected the enzyme completely from heat denaturation; NADP+ and GSH offered some protection but NADPH provided none. The supernatant from the 60 degrees C heat treatment was further purified by affinity chromatography on 2',5'-ADP-agarose. Overall purification was 200-fold with a yield of 80%. The pH optimum of the purified enzyme was 7.0. The KmS for NADPH and GSSG were 19 microM and 78 microM, respectively. The heat inactivation properties of the purified enzyme were identical to those in the crude extract. An enzyme activity stain on disc gel electrophoresis showed that the enzyme exists in only one form.