3D-Printed Franz cells - update on optimization of manufacture and evaluation.

OBJECTIVES: Laboratory in vitro permeation processes require the use of modified Franz type diffusion cells which are conventionally fabricated from glass. Fragility and high cost are frequently associated with this type of laboratory apparatus. The purpose of our present research was to develop a simple, economical and versatile approach to manufacture Franz type cells using additive manufacturing (AM). METHODS: Graphical Franz diffusion cell designs were reproduced with a stereolithography (SLA) 3D printer and assessed over a minimum period of 24 h. The surface morphology of AM printouts was analysed before and after compatibility studies using scanning electron microscopy (SEM). Comparative permeation studies in both glass and AM Franz type diffusion cells were conducted using a caffeine solution (1.5 mg mL-1 ), applied to a model silicone membrane. RESULTS: Testing of the 3D printed scaffolds confirmed similar recovery of the permeant when compared to glass cells: 1.49 ± 0.01 and 1.50 ± 0.01 mg mL-1 , respectively, after 72 h. No significant differences were visible from the SEM micrographs demonstrating consistent, smooth and non-porous surfaces of the AM Franz cells' core structure. Permeation studies using transparent 3D printed constructs resulted in 12.85 ± 0.53 µg cm-2 caffeine recovery in the receptor solution after 180 min with comparable permeant recovery, 11.49 ± 1.04 µg cm-2 , for the glass homologues. CONCLUSION: AM constructs can be considered as viable alternatives to the use of conventional glass apparatus offering a simple, reproducible and cost-effective method of replicating specialised laboratory glassware. A wider range of permeants will be investigated in future studies with these novel 3D printed Franz diffusion cells.

OBJECTIF: les processus de perméation in vitro en laboratoire nécessitent l'utilisation de cellules de diffusion de type Franz modifiées, fabriquées traditionnellement en verre. La fragilité et un coût élevé sont fréquemment associés à ce type d'appareil de laboratoire. L'objectif de nos travaux de recherche actuels était de développer une approche simple, économique et polyvalente pour fabriquer des cellules de type Franz à l'aide de la fabrication additive (FA). MÉTHODES: les conceptions des cellules de diffusion Franz graphiques ont été reproduites avec une imprimante 3D stéréolithographie (SLA) et évaluées sur une période minimum de 24 h. La morphologie de surface des impressions FA a été analysée avant et après des études de compatibilité à l'aide de la microscopie électronique à balayage (MEB). Des études comparatives de perméation des cellules de diffusion de type Franz en verre et FA ont été réalisées à l'aide d'une solution de caféine (1,5 mg ml-1 ) appliquée à un modèle de membrane en silicone. RÉSULTATS: les tests des supports imprimés 3D ont confirmé une récupération similaire du perméant par rapport aux cellules de verre : 1,49 ± 0,01 et 1,50 ± 0,01 mg ml-1 , respectivement, après 72 h. Aucune différence significative n'a été observée sur les micrographiques MEB, montrant des surfaces cohérentes, lisses et non poreuses de la structure centrale des cellules Franz FA. Les études de perméation utilisant des constructions transparentes imprimées en 3D ont conduit à une récupération de la caféine de 12,85 ± 0,53 µg cm-2 dans la solution de récepteur après 180 min avec une récupération de perméant comparable, 11,49 ± 1,04 µg cm-2 , pour les homologues de verre. CONCLUSION: les constructions FA peuvent être considérées comme des alternatives viables à l'utilisation d'appareils de verre conventionnels offrant une méthode simple, reproductible et rentable de réplication de la verrerie de laboratoire spécialisée. Une gamme plus large de perméants sera étudiée dans de futures études avec ces nouvelles cellules de diffusion Franz imprimées en 3D.

3D-printed Franz type diffusion cells.

OBJECTIVE: Franz cells are routinely used to measure in vitro skin permeation of actives and must be inert to the permeant under study. The aim of the present work was to develop and manufacture transparent Franz-type diffusion cells using 3D printing. Printouts were then tested using a range of model active compounds. The study also aims to identify the critical 3D-printing parameters necessary for the process, including object design, choice of printing resin, printout curing and post-curing settings and introduction of model coatings. METHODS: Transparent Franz cells were constructed using an online computer aided design program and reproduced with different stereolithography 3D printers. The two acrylate-based resins used for the fabrication process were a commercially available product and a polymer synthesised in-house. Comparative studies between glass and 3D-printed Franz cells were conducted with selected model actives: terbinafine hydrochloride (TBF), niacinamide (NIA), diclofenac free acid (DFA) and n-methyl paraben (MPB). In preliminary studies, MPB showed the lowest recovery when exposed to the receptor compartment of 3D printed cells. Consequently, in vitro permeation studies were carried out using only MPB with polydimethylsiloxane (PDMS) membrane. RESULTS: A decrease in the amounts of selected compounds was observed for transparent 3D-printed Franz cells compared to glass cells. MPB showed the lowest recovery (53.8 ± 13.1%) when compared with NIA (74.9 ± 4.0%), TBF (81.5 ± 12.0%) and DFA (90.2 ± 12.9%) after 72 h. Permeation studies conducted using 3D-printed transparent cells with PDMS membrane also showed a decrease in MPB recovery of 51.4 ± 3.7% for the commercial resin and 94.4 ± 3.5% for the polymer synthesised in-house, when compared to glass cells. Although hydrophobic coatings were subsequently applied to the 3D-printed cells, the same reduction in MPB concentration was observed in the receptor solution. CONCLUSION: Transparent Franz cells were successfully prepared using 3D printing and were observed to be robust and leak-proof. There are few resins currently available for preparation of transparent materials and incompatibilities between the actives investigated and the 3D-printed cells were evident. Hydrophobic coatings applied as barriers to the printed materials did not prevent these interactions.

Maternal fructose intake aggravates the harmful effects of a Western diet in rat male descendants impacting their cholesterol metabolism.

Scope: fructose consumption from added sugars correlates with the epidemic rise in MetS and CVD. Maternal fructose intake has been described to program metabolic diseases in progeny. However, consumption of fructose-containing beverages is allowed during gestation. Cholesterol is also a well-known risk factor for CVD. Therefore, it is essential to study Western diets which combine fructose and cholesterol and how maternal fructose can influence the response of progeny to these diets. Methods and results: a high-cholesterol (2%) diet combined with liquid fructose (10%), as a model of an unhealthy Western diet, was administered to descendants from control and fructose-fed mothers. Gene (mRNA and protein) expression and plasma, fecal and tissue parameters of cholesterol metabolism were measured. Interestingly, progeny from fructose-fed dams consumed less liquid fructose and cholesterol-rich chow than males from control mothers. Moreover, descendants of fructose-fed mothers fed a Western diet showed an increased cholesterol elimination through bile and feces than males from control mothers. Despite these mitigating circumstances to develop a proatherogenic profile, the same degree of hypercholesterolemia and severity of steatosis were observed in all descendants fed a Western diet, independently of maternal intake. An increased intestinal absorption of cholesterol, synthesis, esterification, and assembly into lipoprotein found in males from fructose-fed dams consuming a Western diet could be the cause. Moreover, an augmented GLP2 signalling seen in these animals would explain this enhanced lipid absorption. Conclusions: maternal fructose intake, through a fetal programming, makes a Western diet considerably more harmful in their descendants than in the offspring from control mothers.

Twenty-four hour rhythm of plasma prolactin in female rabbit pups. Correlation with hypothalamic and adenohypophysial dopamine, serotonin, gamma-aminobutyric acid and taurine content.

Lactation in the rabbit is a nocturnal activity, extremely short and regular, that can be a strong synchronizer for the development of circadian rhythmicity in the pups. In the present study, 24-h rhythmicity of plasma prolactin and median eminence and anterior pituitary content of dopamine (DA), serotonin (5HT), gamma-aminobutyric acid (GABA) and taurine were examined in 11 days old female pups kept under 16 h light:8 h dark photoperiods (lights on at 08:00 h). Groups of six to seven female rabbit pups were killed by decapitation at six different time points throughout a 24-h cycle, starting at 09:00 h. Plasma prolactin levels changed significantly throughout the day, showing two peaks, one at first half of rest span (at 13:00 h) and another one at the beginning of the scotophase (at 01:00 h), just preceding doe visit. Median eminence DA content changed in a bimodal way as a function of time of day, displaying two maxima, at the beginning of the rest span and of the activity phase. Median eminence DA and plasma prolactin correlated significantly in an inverse way. Two maxima in median eminence 5HT levels were found, about 4 h in advance to the prolactin peaks. Circulating prolactin correlated inversely with median eminence 5HT content and directly with adenohypophysial 5HT content. Median eminence GABA content reached its maximum at the beginning of the scotophase and correlated significantly with plasma prolactin concentration. A positive correlation between plasma prolactin and adenohypophysial taurine content was observed. These results show that the circadian rhythmicity in prolactin secretory mechanisms in female rabbit pups develops during the early neonatal life.

Intravascular papillary endothelial hyperplasia (IPEH). Evidence supporting a piecemeal mode of angiogenesis from vein endothelium, with vein wall neovascularization and papillary formation.

Intravascular papillary endothelial hyperplasia (IPEH) is a reactive process of questioned pathogenesis (primary proliferation of endothelial cells/ECs versus organizing thrombi). The aim of this study is to assess the organization of morphologic patterns, with precise location of neovascularization and papillary distribution in IPEH to clarify the role of the vein wall (mainly vein intimal ECs) in lesion development and papillary formation. We studied 12 cases of IPEH in skin and subcutaneous veins by serial histological sections and immunohistochemical procedures. In four well-structured cases (the remaining cases showed overlapping events), we found four principal histological patterns organized by zone: 1) invaginated vein wall zone with microvascular networks. The intraparietal microvessels presented CD34+ and CD31+ ECs arising from ECs of the vein intima, and αSMA+ pericyte-like cells originating from modified SMCs of the media layer. 2) Papillary zone, generally with myriad papillae, formed by ECs of intraparietal microvessel networks encircling vein wall components (parietal papillae). 3) Organizing thrombotic zone from microvascular networks of invaginated vein wall zone. 4) Unorganized thrombotic zone partially covered by ECs, also originating from vein intimal endothelium and arranged in a monolayer or encircling thrombotic fibrin (thrombotic papillae). In conclusion, the capacity of vein intimal ECs and those originating from them (in newly-formed microvessels in the vein itself and covering the unorganized thrombi) to encircle vein wall components or fibrin, and to form papillae (ECs form the cover and encircled components the core) supports a piecemeal mode of angiogenesis as a pathogenic basis of IPEH. This mechanism encompasses the two histogenetic hypotheses outlined above.

Intradural herniated dorsal disc: case report and review of the literature.

A 67-year-old man with a 1 1/2-month history of spastic paraparesis caused by a dorsal intradural disc herniation underwent surgical treatment via a posterior approach. Dorsal herniated discs are rare, and intradural dorsal disc herniations are even more infrequent. Including this case, the medical literature reviewed describes only four such cases.

Cimetidine does not alter sparfloxacin pharmacokinetics.

The interaction between cimetidine and sparfloxacin was studied in 10 healthy volunteers who received a single oral dose of 400 mg sparfloxacin on the third day of an 8 day cimetidine (400 mg t.i.d.) or placebo randomly assigned treatment. No statistically significant differences were observed in the pharmacokinetic parameters (Cmax-AUC-T1/2-urinary excretion and metabolic ratio) of sparfloxacin following the 2 treatment. Cimetidine does not affect absorption, metabolism or urinary excretion of sparfloxacin; consequently, patients exposed to this drug combination are not at risk.

Pineal region meningiomas without dural attachment.

A rare case of meningioma in the pineal region without dural attachment, which was successfully removed through an infratentorial supracerebellar approach, is presented. The preoperative diagnosis was made by means of computed tomography together with histographic analysis. We review similar cases reported in the literature and discuss the clinical feature, diagnostic aspects, and surgical management.

[Pharmacovigilance study of azithromycin tablets (500 mg) in the treatment of adult patients with respiratory tract infections]. / Estudio de farmacovigilancia de azitromicinacomprimidos (500 mg) en el tratamiento de pacientesadultos con infecciones de vías respiratorias. Grupo colaborador.

Our aim was to study a new form of azithromycin (500 mg tablets) in order to evaluate the tolerability and the influence of the ingestion of food on tolerability, the efficacy and treatment compliance in a large number of patients with respiratory tract infections. We carried out an open, non-comparative, multicenter, observational and prospective pharmacovigilance study of 3223 outpatients with respiratory tract infections randomly assigned to receive a daily dose of azithromycin for three months taken either during or outside meals. Patients were evaluated during an initial visit and two later ones in order to record the adverse events and establish the clinical efficacy. The diagnostics were as follows: pharyngotonsillitis (1200), acute otitis media (394), acute bronchitis (1134), exacerbation of chronic bronchitis (436), and community-acquired pneumonia (53). The overall therapeutic efficacy was satisfactory (cure or improvement) in 96% to 97% at the second visit and in 93% to 94% in the third (pharyngotonsillitis, 93%; acute otitis media, 91%; acute bronchitis, 94%; exacerbation of chronic bronchitis, 94%; and community-acquired pneumonia, 96%). A total of 170 adverse events were reported in 141 patients (4.4%); 12 were severe yet not related to the study medication. Eighty-eight patients showed adverse events presumed to be related to azithromycin; most were in the digestive tract. No differences in tolerability were observed in relation to food intake. Treatment compliance was high (97%). The elevated clinical efficacy, adequate compliance and the excellent tolerability profile of azithromycin tablets make them a safe and effective alternative in the treatment of respiratory tract infections.

Effects of overexpression of growth hormone on T cell activity in transgenic mice.

Growth hormone plays a key role in the maturation and maintenance of the immune response, however, the effects of chronic high circulating concentrations of the hormone on the immune system is poorly understood. Transgenic mice overexpressing bovine growth hormone (b-GH) gene, fused to the rat phosphoenolpyruvate carboxykinase promoter (PEPCK), with very high plasma concentration of heterologous b-GH and their littermate normal siblings were used. Spleen cellularity, percentages of total T lymphocytes, CD4+ and CD8+ cells, ratio of T cell subpopulations, mitogen-induced lymphocyte proliferation and natural killer (NK) cell activity were examined in male transgenic mice and normal littermate mice at 2 and 6 months of age. The number of splenic lymphocytes was greater in transgenic mice than in matched normal littermates at both ages. The NK cell activity was lower in transgenic mice than in the matched normal littermates at both ages, with the lowest values found in older mice. The b-GH transgenic mice had lower percentages of T cells at both ages, however, in young transgenic mice, the percentage of CD4+ cells was reduced while percentage of CD8+ cells was increased in comparison to normal controls. Both basal and mitogen-induced proliferation capacity of splenocytes were reduced in PEPCK-b-GH-25 mice as compared to normal littermates of both ages. Proliferative indexes in response to concanavalin A and phytohemagglutinin were markedly decreased in 6 month old PEPCK-b-GH-25 mice as compared to littermate controls or younger mice. These results indicate that overexpression of b-GH in mice is associated with decreased T cell function and that these abnormalities are age-dependent.

Natal molars in Pfeiffer syndrome type 3: a case report.

The following report is the first documented case of natal teeth associated with a recently described new entity, Pfeiffer syndrome type 3. The clinical manifestations consistent with the spectrum of this rare disorder are described with an emphasis on the concomitant natal teeth. Pfeiffer syndrome type 3 is one of the craniosynostosis syndromes and has been described in only two patients to date. Both mandibular incisors and maxillary molar natal teeth were found. Natal teeth are teeth, which are present in the oral cavity at birth. They are often associated with developmental abnormalities and recognized syndromes. Their incidence ranges from 1 in 2,000 to 3,500 births. The natal teeth found in this infant included both the mandibular primary incisors and maxillary primary first molars bilaterally. The clinical and histological considerations of natal teeth and their management are discussed. The presence of multiple natal teeth is extremely rare.

[Ectopic ovarian pregnancy]. / Embarazo ectópico ovárico.

Ovarian ectopic pregnancy is a rare form of ectopic pregnancy, with an estimated incidence ranging from 0.5% to 3% of the extrauterine pregnancies. For a correct diagnosis of the ovarian pregnancy, the traditional criteria proposed by Spiegelberg in 1878 must be fulfilled. This forced us sometimes to reject pregnancies which, despite being initially ovarian, during its evolution the adjacent tubal structures have been affected. Currently, the ectopic pregnancies are being diagnosed more early, mainly given the echographic advances, which have lead to very conservative treatments in order to avoid a reduced fertility. However, it is many times an intraoperative diagnosis. We present four new cases of ovarian ectopic pregnancy from our casuistry of the last three years with anatomoclinical study and literature review.

[Agranulocytosis caused by metamizol. Anesthetic attitude]. / Agranulocitosis por metamizol. Actitud anestésica.

Agranulocytosis induced by metamizole is uncommon, with a frequency of less than one case per million treatments. We describe such a case in a patient requiring emergency surgery. An 85-year-old man with a history of infantile paralysis with mental retardation and Paget's disease and X-ray signs of the right femur came to the emergency room with a diaphysial fracture. He received 1 g metamizole i.v. every 8 hours for analgesia. Ten hours after admission a routine blood cell count showed a rapid fall in the number of leukocytes; at 24 hours the count was 600 x 10(9)/l. The diagnosis was agranulocytosis induced by metamizole. Postponement of surgery was advisable and treatment with granulocyte colony stimulating factor (GCSF) at a dose of 5 micrograms/kg/day. Agranulocytosis resolved after 3 days of treatment, after which time the bone was set with a straight femoral plate under subarachnoid anesthesia. Two packs of red blood cells were required during the immediate postoperative period. Twelve days after surgery the patient was released. We review the anesthetic approach to agranulocytosis and its treatment.

[Comparative study of postoperative analgesia with methadone and fentanyl in continuous peridural perfusion]. / Estudio comparativo de la analgesia postoperatoria con metadona y fentanilo en perfusión peridural continua.

OBJECTIVE: To determine whether continuous epidural perfusion of fentanyl, which is more liposoluble than methadone, provides a similar level of analgesia with fewer side effects than methadone administered by the same route for postoperative pain. PATIENTS AND METHODS: Prospective double blind study of 40 patients, randomly assigned to two groups. Group F (n = 20) received 300 micrograms-1200 micrograms/24 h in epidural perfusion. Group M (n = 20) received 9 mg-18 mg/24 h in epidural perfusion. In both cases treatment was for pain in the first 72 h after abdominal surgery. Analgesia quality was evaluated on a visual analog (VAS) scale from 1 to 10 at rest and moving. Need for complementary analgesia was also recorded, as were side effects related to the technique. RESULTS: Quality of analgesia was good and similar which both drugs. Postoperative pain did not surpass 3 on the VAS at rest or 4.5 while moving, although group F patients' need for complementary analgesia was significantly greater (p < 0.05). The incidence of hypoxemia was greater in group M than in group F (p = 0.05). CONCLUSIONS: Continuous epidural perfusion of fentanyl provides good analgesia and is associated with less hypoxemia than is methadone.

[Clinical trial of lovastatin versus gemfibrozil in the treatment of primary hypercholesterolemia]. / Estudio clínico de lovastatina frente a gemfibrozil en el tratamiento de la hipercolesterolemia primaria.

A randomized, double-blind, 12 weeks comparison of Lovastatin and Gemfibrozil in the treatment of patients with primary hypercholesterolemia was performed in 31 patients. After a placebo and diet period (4 weeks), they were assigned to either Lovastatin 20 mg nightly or Gemfibrozil 600 mg twice daily, if their total serum cholesterol was < 300 mg/dl, and to either Lovastatin 40 mg nightly or Gemfibrozil 600 mg/12 if it was > 300 mg/dl. In both cases, the Lovastatin dose was doubled after 6 weeks, if serum cholesterol remained > 200 mg/dl. The dose of Gemfibrozil kept constant. Lovastatin reduced serum cholesterol from 354 +/- 91 mg/dl to 253 +/- 62 mg/dl (p < 0.001), LDL-cholesterol from 277 +/- 104 to 192 +/- 71 mg/dl (p < 0.001) and serum triglyceride level from 125 +/- 66 a 84 +/- 41 mg/dl. The corresponding reductions achieved by Gemfibrozil were: 343 +/- 86 to 290 +/- 72 mg/dl (p < 0.01), 264 +/- 89 to 217 +/- 67 mg/dl (p < 0.05) and 152 +/- 84 to 89 +/- 41 mg/dl (p < 0.001), respectively. Lovastatin therapy caused a 30.6% reduction in total cholesterol level, while Gemfibrozil achieved a 19.47%. There were no significant changes in HDL-cholesterol. Patients had no serious or clinically significant adverse effects. The current data suggest that Lovastatin (an inhibitor of HMG-Coa reductase) may provide one important means for lipid-lowering therapy in patients with primary hypercholesterolemia.