Comparative enhancer effects of Span20 with Tween20 and Azone on the in vitro percutaneous penetration of compounds with different lipophilicities

Sorbitan monolaurate (Span20) was used in this study to analyze the influence of the polar functional group on the effects that non-ionic surfactants have on skin permeability. Its ethoxylate derivative polysorbate 20 (Tween20) and Azone, both with the same C12 alkyl chain as Span20, were used for comparative purposes. We evaluated the relative potency of the three molecules as enhancers in the permeability of a series of compounds with lipophilicities ranging from log Poct=-0.95 to log Poct=2.33. The influence of the enhancer concentration was also studied. For this purpose the epidermis of Wistar rat was pretreated with ethanolic solutions (1 and 5%, w/v) of each enhancer. Our results indicate that the nature of the enhancer head group greatly influences cutaneous barrier impairment. The enhancer concentration must also be taken into account, even though the influence of the concentration seems to depend on the lipophilicity of the penetrant assayed.

The distribution of the major peripheral blood T, B and NK cell subsets does not predict the clinical outcome of Graves' disease patients after methimazole therapy

Biological markers capable of predicting the clinical outcome of antithyroid drug therapy could be clinically useful in selecting the modality of treatment for Graves' disease, but at present they are unavailable. In the present study we prospectively explore the value of 22 different peripheral blood T, B and NK lymphocyte subsets to predict remission and relapse in a group of 42 Graves' disease patients. Eighteen patients were studied at diagnosis, before treatment, and 24 during antithyroid drug therapy. All cases were followed-up for at least one year after finishing an 18 month cycle of methimazole therapy. The combination of flow cytometry and 3- color immunofluorescence did not reveal significant differences in the distribution of the major peripheral blood T, B and NK cell subsets between the relapsed patients and those in remission, both in the groups studied at diagnosis and in those analyzed during the cycle of antithyroid drug therapy. In our search for a prognostic marker for relapse prediction we found that some lymphoid subpopulations such as total B cells, total NK and NK CD8+ cells showed high sensitivity (88-100%). In turn, other subsets such as TCD8+, total T and B cells expressing the CD25 antigen displayed high specificity (77-88%).

Neuropeptides bombesin and calcitonin induce resistance to etoposide induced apoptosis in prostate cancer cell lines

BACKGROUND

Neuroendocrine differentiation in prostatic carcinoma has been related to regulation of proliferation and metastatic potential and correlated with prognosis. More than 80% of prostate carcinomas initially respond to androgen ablation, but most relapse, due to the heterogeneous presence of androgen-dependent and independent clones. The pathways of cellular proliferation and apoptosis are inexorably linked to minimize the occurrence of neoplasia, and disfunction of apoptosis is proposed as a pathogenic process in malignant tumors. Androgen-dependent prostatic cancer cells undergo apoptosis after androgen deprivation, but not androgen-independent ones due to a defect in the initiation step. Anyway, they retain the basic cellular machinery to undergo apoptosis. We suggest a possible role of neuroendocrine differentiation in the onset and regulation of apoptosis in prostatic neoplasia.

METHODS

LNCaP, PC-3 and DU 145 prostatic cancer cell lines were induced to undergo apoptosis after treatment with etoposide alone or plus androgen ablation. We tested the role of neuropeptides bombesin and calcitonin at modulating etoposide induced apoptosis.

RESULTS

Etoposide-induced apoptosis in all cancer cell lines was achieved. In LNCaP androgen ablation was also required. Apoptosis is prevented in all three lines when bombesin was added. Calcitonin addition prevents apoptosis in PC-3, LNCaP and in an etoposide dose-dependent way in DU 145.

CONCLUSION

Neuropeptides bombesin and calcitonin can modulate the apoptotic response of prostate cancer cells by inducing resistance to etoposide-induced apoptosis, suggesting that neuropeptides can be used as a target of therapeutical approach in prostatic carcinoma.

[Aspergillosis in pulmonary transplantation]

BACKGROUND

Fungal infections are a frequent cause of morbidity an mortality in transplant recipients. Aspergillus spp. is an ubiquitous fungus capable of producing diverse clinical entities with varying severity.

OBJECTIVE

To study the incidence and severity of Aspergillus spp. infections in lung transplantation, analysing the different clinical presentations and response to antifungal drugs.

METHODS

A review was made of the clinical histories of all patients undergoing lung transplantation who developed positive Aspergillus spp. cultures in our centre between June 1991 and December 1996.

RESULTS

Eleven of 49 transplanted patients (22%) developed Aspergillus spp. infections. Four patients presented invasive aspergillosis forms and 7 tracheobronchitis. In spite of antifungal treatment 3 patients (30%) died of invasive aspergillosis as a direct consequence of the infection. Of the 7 patients with tracheobronchitis, 2 were ulcerative and 1 pseudomembranous, all responded to antifungal treatment. Three patients (10.3%) developed Aspergillus spp. infections despite prophylaxis with itraconazole.

CONCLUSION

Invasive aspergillosis in the immediate posttransplant period was mortal despite treatment. As opposed, aspergillar tracheobronchitis have been overcome using combined treatments of liposomal or lipidic amphotericin, itraconazole and nebulised amphotericin.

Extramedullary plasmacytoma in a horse with ptyalism and dysphagia

A Clydesdale mare was examined for weight loss, inappetence, ptyalism, and dysphagia. The main abnormality revealed by serum biochemistry was a marked hyperglobulinemia, and protein electrophoresis revealed a monoclonal gammopathy in the gamma region. The urine was positive for Bence Jones proteins. These findings suggested a plasma cell tumor. The neoplasm could not be located with extensive antemortem examination. At postmortem, neoplastic cells morphologically compatible with plasma cells and positive for equine IgG with imunoperoxidase staining infiltrated the pericardium, mediastinal stromal tissues, adrenal glands, meninges, atrioventricular valves, aorta, abdominal and thoracic fat, and nerves, including the trigeminal nerve. The neoplastic cells invading the cranial nerves were responsible for many of the presenting signs.

Magnesium-induced linear self-association of the FtsZ bacterial cell division protein monomer. The primary steps for FtsZ assembly

The bacterial cell division protein FtsZ from Escherichia coli has been purified with a new calcium precipitation method. The protein contains one GDP and one Mg(2+) bound, it shows GTPase activity, and requires GTP and Mg(2+) to polymerize into long thin filaments at pH 6.5. FtsZ, with moderate ionic strength and low Mg(2+) concentrations, at pH 7.5, is a compact and globular monomer. Mg(2+) induces FtsZ self-association into oligomers, which has been studied by sedimentation equilibrium over a wide range of Mg(2+) and FtsZ concentrations. The oligomer formation mechanism is best described as an indefinite self-association, with binding of an additional Mg(2+) for each FtsZ monomer added to the growing oligomer, and a slight gradual decrease of the affinity of addition of a protomer with increasing oligomer size. The sedimentation velocity of FtsZ oligomer populations is compatible with a linear single-stranded arrangement of FtsZ monomers and a spacing of 4 nm. It is proposed that these FtsZ oligomers and the polymers formed under assembly conditions share a similar axial interaction between monomers (like in the case of tubulin, the eukaryotic homolog of FtsZ). Similar mechanisms may apply to FtsZ assembly in vivo, but additional factors, such as macromolecular crowding, nucleoid occlusion, or specific interactions with other cellular components active in septation have to be invoked to explain FtsZ assembly into a division ring.

Iontophoresis: electrorepulsion and electroosmosis

Over the last 10-15 years, the electrical enhancement of drug delivery across the skin has undergone intense investigation. During this period, considerable amounts of experimental data have been generated, and the successful enhancement of a diverse array of molecules has been achieved. Indeed, the commercial exploitation of the method can be envisaged within the next few years. Despite this progress, however, the mechanistic understanding of iontophoresis remains a challenging scientific question that is yet to be fully resolved. The routes of permeation under the influence of an applied electrical potential, and the molecular interactions of the transporting drug with these pathways, have resisted unequivocal and unambiguous identification. Equally, the relative contributions of electrorepulsion and electroosmosis to the total iontophoretic flux have proven difficult to quantify, due to the difficulty of designing appropriate experiments. The situation is further complicated by the fact that it has now been established that certain lipophilic cations, in particular, can associate strongly with the skin during their iontophoretic delivery, thereby altering the electrical properties of the membrane, and changing the mechanism of transport. In this short communication, the roles of electrorepulsion and electroosmosis have been reconsidered from a simple theoretical point of view, and experimental approaches by which their relative importance may be estimated have been proposed and subjected to initial evaluation.

Pharyngeal bot flies in Cervus elaphus in central Spain: prevalence and population dynamics

The prevalence and intensity of infestations by bot flies Pharyngomyia picta and Cephenemyia auribarbis in red deer (Cervus elaphus) from Quintos de Mora (Toledo, Spain) were determined over a 1-yr period. Bots were present all year. No clear correlations were found between age or sex of the host and parasitization levels (prevalence and intensity). Considerable variation was found in prevalence and intensity, with larger values from December to March. Cephenemyia auribarbis was restricted from November to March, with maximum numbers of L-3 in February. Pharyngomyia picta showed a more complex profile with 2 peaks (March and August), indicating 2 generations per year.

Anesthetic management of surgical neuroendoscopies: usefulness of monitoring the pressure inside the neuroendoscope

Neuroendoscopic procedures are increasing in frequency in neurosurgical practice. We describe the anesthetic technique and the perioperative complications found in 100 neuroendoscopic interventions performed at our institution. Cranial tumor biopsy or retrieval (62%) and cisternostomy for hydrocephalus (33%) were the most frequent indications for neuroendoscopy. The mortality rate was low (1%). Intraoperative complications occurred in 36 patients, with arterial hypertension being the most frequent (53%). Postoperative complications occurred in 52 patients; anisocoria (31%) and delayed arousal (29%) were the most frequent. The pressure inside the endoscope was monitored intraoperatively in the last 47 patients. A saline-filled catheter from a pressure transducer connected to the neuroendoscopy system was used for pressure monitoring. We recorded the highest peak of pressure values measured during each procedure. Twenty-three patients (49%) had peak pressure values >30 mm Hg, 12 patients (25%) >50 mm Hg, and 3 patients >100 mm Hg. Only one patient had hemodynamic changes occurring simultaneously with the pressure changes. We found an association between pressure inside the endoscope >30 mm Hg and postoperative (P = .003) but not intraoperative complications. A relationship was found between surgical duration and postoperative complications (P = .002). Neither the pressure inside the endoscope or the intraoperative morbidity were related to surgical duration. We conclude that there may be a high rate of postoperative complications after neuroendoscopies, namely, new neurologic deficits. High pressure levels inside the endoscope during neuroendoscopic procedures can occur without hemodynamic warning signs. Pressure values >30 mm Hg are associated with postoperative morbidity, especially unexpected delayed recovery. Measuring the pressure inside the endoscope is technically easy and might be beneficial if performed in all neuroendoscopic procedures. Reducing the incidence of episodes of high peak pressure values might decrease the rate of postoperative complications.

Cutaneous mucinosis and mastocytosis in a shar-pei

A 7-year-old shar-pei was presented because of a recurrent dermatologic condition. Skin biopsies revealed an idiopathic (primary) cutaneous mucinosis that initially responded to corticosteroids. The condition reappeared 2 years later and subsequent biopsies revealed a mast cell tumor in some of the skin sites previously diagnosed with mucinosis.

Effect of emu oil on auricular inflammation induced with croton oil in mice

OBJECTIVE

To determine the acute anti-inflammatory effects of topically applied emu oil.

ANIMALS

96 male CD-1 mice assigned randomly to 4 groups, each comprising 24 mice.

PROCEDURE

To induce auricular inflammation, 50 microl of a solution comprising 10 microl of croton oil dissolved in 1 ml of acetone was applied to the inner surface of the left auricle (pinna). One hour later, 3 or 5 microl of emu oil (low- and high-dose groups, respectively) or 5 microl of porcine oil (oil-control) was applied to the left pinna. Control mice remained untreated. Six mice per group were euthanatized 3, 6, 12, and 24 hours after induction of inflammation. Specimens of auricular tissue (ear plugs) were obtained, using a 6-mm biopsy punch. Magnitude of swelling was calculated as the weight difference between left (inflamed) and right (noninflamed) ear plugs; degree of edema was determined as the difference between wet and dry weights of the left ear plug.

RESULTS

Magnitude of swelling was significantly reduced at 6 and 12 hours in mice treated with emu or porcine oil, compared with controls. The greatest reduction in swelling was detected in the high-dose emu group at 6 hours. Compared with controls, degree of edema was significantly reduced at 6 hours only in the high-dose group, whereas by 12 hours, all groups treated with oils had significantly less edema than controls. At 24 hours, magnitude of swelling and degree of edema did not differ among groups.

CONCLUSION

Topically applied emu oil significantly reduced severity of acute auricular inflammation induced by croton oil in mice.

Evaluation of acute and chronic hepatotoxic effects exerted by anabolic-androgenic steroid stanozolol in adult male rats

Stanozolol (ST) is a 17alpha-alkyl anabolic-androgenic steroid (17alpha-AAS) often misused by athletes and bodybuilders. The use of anabolic-steroids by sportsmen and teenagers has increased dramatically, thus raising the question about their hepatotoxicity, specially those such as ST which are orally administered. Previously, we have reported diverse in vivo effects exerted by this steroid and published the existence of a highly specific ST-binding site in male rat liver microsomes. The existence of this binding site, the reported hepatic effects exerted in humans, and the very limited information about its potential hepatotoxicity led us to treat adult male rats acutely and chronically with ST and study different parameters that could indicate liver damage: serum levels of transaminases, concentration of monooxygenase enzymes in liver, liver membrane lipid peroxidation products, liver histopathology, and cell cycle/ploidy status of liver cells. In our study, no changes in serum transaminases or lipid peroxidation levels were obtained. However, acute stanozolol treatment significantly decreased the levels of cytochrome P450 (Cyt. P450) and cytochrome b5 (Cyt. b5) during the first 48 h of treatment, while subsequently, at 72 and 96 h, these microsomal enzymes underwent a significant increase in their levels. In sharp contrast with this response to acute treatment, the content of these two enzymes during chronic treatment showed an important decrease. Interestingly, acutely and chronically ST-treated livers showed slight to moderate inflammatory or degenerative lesions in centrilobular hepatocytes. Flow cytometric analysis demonstrated that both acute and chronic ST treatment were capable of increasing the percentage of S-phase fraction (%SPF) of liver cells. These findings taken together clearly show that this steroid is capable of altering the liver capacity for metabolizing xenobiotics and indicate that high doses of ST could exert a proliferative effect on liver cells. Such data should be considered in risk evaluations for this compound.

Chronic alcoholism is associated with an imbalanced production of Th-1/Th-2 cytokines by peripheral blood T cells

BACKGROUND

In the present study, we analyzed, at the intracellular level, the pattern of cytokine secretion by the major CD4+ and CD8strong+ peripheral blood (PB) T-cell subsets in patients with chronic alcoholism, and we correlated it both with the ethanol (EtOH) intake status and with the presence or not of alcoholic liver disease.

METHODS

For that purpose, a total of 30 chronic alcoholic patients, 10 without liver disease (AWLD group) and 20 diagnosed with alcoholic liver cirrhosis (ALC) were studied. In all cases, flow cytometric measurement of intracellular expression of interferon-gamma (IFN-gamma), interleukin (IL)-2, and IL-4 was performed on PB CD4+ and CD8strong+ T lymphocytes.

RESULTS

After studying AWLD patients, we found increased numbers of both CD4+ and CD8strong+ PB T cells with detectable cytoplasmic levels of the IL-2 and IFN-gamma T helper (Th)-1-associated cytokines, the greater increase being observed for this latter cytokine (p<0.001 for CD4+ and p<0.01 for CD8strong+ T cells). Regarding ALC patients, the pattern of expression of intracellular cytokines by PB T cells was different depending on the status of EtOH intake at the moment of entering this study. Accordingly, as in AWLD patients, ALC individuals who were actively drinking also displayed increased numbers of both CD4+ and CD8strong+ T cells expressing Th-1-associated cytokines. However, in these patients, expression of IFN-gamma, although being significantly greater than that observed in control individuals (p<0.05), was significantly lower than that in AWLD patients (p<0.01 and p<0.05, for CD4+ and CD8strong+ T cells, respectively). After a withdrawal period of > or =1 yr, ALC patients did not show significant changes in the cytoplasmic expression of Th-1-associated cytokines compared with the control group; in contrast, these patients showed a marked increase on the proportion of CD4+ and CD8strong+ T cells expressing IL-4, a Th-2-associated cytokine (p<0.01). After considering the ratio between the number of T cells expressing Th- (IFN-gamma)- and Th-2 (IL-4)-associated cytokines in each individual, we found that there was a significant imbalance in this ratio, with a predominance of IFN-gamma-producing T cells over IL-4+ T lymphocytes during EtOH intake.

CONCLUSIONS

Our results showed that in patients with chronic alcoholism, active EtOH intake is associated with a Th-1 pattern of cytokine production by PB T cells.

Feeding frequency and nutritional status of peridomestic populations of Triatoma infestans from Argentina

We studied the nutritional characteristics of peridomestic populations of Triatoma infestans from 25 habitats in an endemic area of Chagas disease in Argentina. The aim was to determine the feeding frequency, fresh weight of adults and older nymphs, and the gonotrophic status of females, in order to compare them with previous studies of domestic populations in the same region. The average infection rate of the bugs and blood meal origins were also determined in order to calculate the maximum risk for Trypanosoma cruzi transmission in these habitats. The number of bugs in each habitat correlated positively with the number of hosts. The estimated number of bites per night was strongly correlated with the total number of bugs collected from that habitat. The shortest biting interval (1.9 and 1.7 days) occurred in November and February, where 52-60% of insects suck blood each night. Adults and nymphs recently fed showed significantly higher fresh weight in November. There was no apparent correlation between the mean weights of adults or nymphs and the number of insects found within each habitat. Bloodmeal analysis showed that most of the bugs (87%) had fed from chicken, with human and dog scarcely represented and no bloodmeals identified from cat. However, human bloodmeals were only identified from chicken coops near the house (< 12 m). Almost all females (92-100%) captured during the spring months had been mated, whereas the proportion of mated females decreased significantly during summer (60-71%). The maximum risk (MR) average from these peridomestic habitats was 0.35 bites from infective bugs/night, tenfold lower than MR from domestic habitats. The good nutritional status of recently fed bugs, found in these chicken coops during all the hot season, suggest that active dispersal is unlikely to occur from peridomestic habitats.

Hemorheological alterations in patients with chronic renal failure. Effect of hemodialysis

The rheological profile of 45 patients who had kidney failure and were undergoing periodical hemodialysis was studied to ascertain whether they showed rheological alterations and if these alterations improved after hemodialysis. Our results indicate that the patients studied suffer rheological alterations with respect to the control group, specifically increased plasma fibrinogen (436 +/- 119 vs 271 +/- 43 mg/dl, p < 0.001), increased plasma viscosity (1.30 +/- 0.10 vs 1.22 +/- 0.05 mPa.s, p < 0.001), higher erythrocyte aggregability (8.3 +/- 1.2 vs 7.4 +/- 1.4, p < 0.01) and a lower hematocrit (31.2 +/- 5.9 vs 43.4 +/-3.7, p < 0.001). In contrast, erythrocyte deformability did not seem to be altered with respect to the control group. The analyses carried out immediately after hemodialysis showed that in general the rheological profile worsened during this treatment; there was a significant increase in fibrinogen and in plasma viscosity. The rheological alterations detected may play a role in the development of the atherosclerosis processes often experienced by these patients.

Apo E influences declarative and procedural learning in age-associated memory impairment

Age-associated memory impairment (AAMI) is a clinical entity which was originally described to define memory problems linked to normal aging. Apolipoprotein E and ACE genes have both been associated with cognitive impairment in aging and dementia. The purpose of this study was to investigate memory and executive functions in AAMI according to the genetic background. We found that subjects carrying the Apo E epsilon4 allele exhibit lower memory performance on tests of both declarative and procedural memory. We did not find differences on frontal lobe tests. These findings give further support to the hypothesis concerning a genetic susceptibility for cognitive impairment in aging.

Analysis of genomic damage in the mutagen-sensitive mus-201 mutant of Drosophila melanogaster by arbitrarily primed PCR (AP-PCR) fingerprinting

DNA repair mechanisms are important to maintain the stability of the genome. In Drosophila melanogaster, the mus-201 gene is required in the excision repair process. To study the contribution of the mus-201 gene in the stability of the Drosophila genome, we have used the arbitrarily primed PCR fingerprinting method (AP-PCR). We have analysed the changes in the genomic DNA fingerprints from the progeny of wild-type males crossed with mus-201 repair-deficient or repair-proficient females. After induction of DNA damage with 2-acetylaminofluorene (2-AAF) in the wild-type parental males, quantitative and qualitative differences in the AP-PCR fingerprints were detected between the two crosses, and the estimate of the genomic damage detected by AP-PCR has clearly shown that the mus-201 repair deficiency is associated with an increase of genomic damage. The predominant type of alterations detected by AP-PCR under the mus-201 repair-deficient conditions agree with the results obtained in microsatellite PCR analysis, suggesting that the role of the mus-201 gene, necessary in excision repair, is not associated to the mismatch repair process. The work reported here demonstrates that the AP-PCR is a suitable technique to analyse genetic alterations in D. melanogaster and, consequently, can be used to compare the susceptibility to genomic damage of different DNA repair mutants.

Sperm viability in ram semen diluted and stored in three different extenders

Semen was collected with an artificial vagina from 4 one-year-old rams, in order to study the changes in sperm motility and membrane integrity of spermatozoa split-diluted and stored at 5 degrees C during 7 days in sodium citrate, Tris, and milk-based extenders, respectively. Sperm motility was assessed subjectively and sperm membrane integrity was determined using the fluorescent probes Calcein-AM and Ethidium homodimer. Representative samples were studied using scanning electron microscopy (SEM). The average incidence of sperm motility decreased over time in all the extenders (p < 0.001). The incidence of spermatozoa showing progressive motility and intact plasma membrane was significantly higher in semen diluted with sodium citrate than in the other 2 extenders following 4 days of dilution until the end of the study. Evaluation with SEM confirmed the findings obtained with the supra vital fluorescent dyes. The results of the present study indicated that there were no differences between sodium citrate-, Tris- or milk-based extenders when ovine liquid semen was stored at 5 degrees C during a short period (2 days). However, when semen was stored for longer time, spermatozoa in the sodium citrate-based extender sustained its viability better.

Response to plasma exchange and steroids as combined therapy for patients with thrombotic thrombocytopenic purpura

We describe our experience in the management of 11 consecutive patients with thrombotic thrombocytopenic purpura (TTP) treated with a combined therapy of plasma exchange (PE) and steroids. Nine patients (82%) achieved complete remission (CR) after a median of 6 rounds of PE (range 2-22). There were 3 early relapses managed in the same way as the initial episode. One patient relapsed 23 months after diagnosis achieving CR with standard therapy; another patient suffered several relapses, and splenectomy was performed after the last one. Three patients died, 2 of them with resistant disease 9 and 38 days after diagnosis, and the remaining one died due to AIDS-related complications while he was in CR. Eight patients are alive in CR with a median follow-up of 38 months (range 8-74). The combination of PE and steroids is a well-tolerated and effective treatment of TTP, but improvements in therapy are needed to manage refractory patients.