Development of a dry powder insufflation device with application in in vitro cell-based assays in the context of respiratory delivery

Research on pharmaceutical dry powders has been increasing worldwide, along with increased therapeutic strategies for an application through the pulmonary or the nasal routes. In vitro methodologies and tests that mimic the respiratory environment and the process of inhalation itself are, thus, essential. The literature frequently reports cell-based in vitro assays that involve testing the dry powders in suspension. This experimental setting is not adequate, as both the lung and the nasal cavity are devoid of abundant liquid. However, devices that permit powder insufflation over cells in culture are either scarce or technically complex and expensive, which is not feasible in early stages of research. In this context, this work proposes the development of a device that allows the delivery of dry powders onto cell surfaces, thus simulating inhalation more appropriately. Subsequently, a quartz crystal microbalance (QCM) was used to establish a technique enabling the determination of dry powder deposition profiles. Additionally, the determination of the viability of respiratory cells (A549) after the insufflation of a dry powder using the developed device was performed. In all, a prototype for dry powder insufflation was designed and developed, using 3D printing methods for its production. It allowed the homogenous dispersion of the insufflated powders over a petri dish and a QCM crystal, and a more detailed study on how dry powders disperse over the supports. The device, already protected by a patent, still requires further improvement, especially regarding the method for powder weighing and the efficiency of the insufflation process, which is being addressed. The impact of insufflation of air and of locust bean gum (LBG)-based microparticles revealed absence of cytotoxic effect, as cell viability roughly above 70 % was always determined.

Respirable konjac glucomannan microparticles as antitubercular drug carriers: Effects of in vitro and in vivo interactions

Pulmonary delivery of drugs is potentially beneficial in the context of lung disease, maximising drug concentrations in the site of action. A recent work proposed spray-dried konjac glucomannan (KGM) microparticles as antitubercular drug (isoniazid and rifabutin) carriers to treat pulmonary tuberculosis. The present work explores in vitro and in vivo effects of these microparticles, focusing on the ability for macrophage uptake, the exhibited antibacterial activity and safety issues. Efficient uptake of KGM microparticles by macrophages was demonstrated in vitro, while the antitubercular activity of the model drugs against Mycobacterium bovis was not affected by microencapsulation in KGM microparticles. Despite the good indications provided by the developed system, KGM is not yet approved for pulmonary applications, which is a limiting characteristic. To reinforce the available data on the performance of the material, safety parameters were evaluated both in vitro and in vivo, showing promising results. No significant cell toxicity was observed at concentrations considered realistic for lung delivery approaches (up to 125 μg/mL) when lung epithelial cells and macrophages were exposed to KGM microparticles (both drug-loaded and unloaded). Finally, no signs of systemic or lung inflammatory response were detected in mice after receiving 10 administrations of unloaded KGM microparticles.

Fucoidan from Fucus vesiculosus: Evaluation of the Impact of the Sulphate Content on Nanoparticle Production and Cell Toxicity

The composition of seaweeds is complex, with vitamins, phenolic compounds, minerals, and polysaccharides being some of the factions comprising their structure. The main polysaccharide in brown seaweeds is fucoidan, and several biological activities have been associated with its structure. Chitosan is another marine biopolymer that is very popular in the biomedical field, owing to its suitable features for formulating drug delivery systems and, particularly, particulate systems. In this work, the ability of fucoidan to produce nanoparticles was evaluated, testing different amounts of a polymer and using chitosan as a counterion. Nanoparticles of 200-300 nm were obtained when fucoidan prevailed in the formulation, which also resulted in negatively charged nanoparticles. Adjusting the pH of the reaction media to 4 did not affect the physicochemical characteristics of the nanoparticles. The IC50 of fucoidan was determined, in both HCT-116 and A549 cells, to be around 160 µg/mL, whereas it raised to 675-100 µg/mL when nanoparticles (fucoidan/chitosan = 2/1, w/w) were tested. These marine materials (fucoidan and chitosan) provided features suitable to formulate polymeric nanoparticles to use in biomedical applications.

Nanoencapsulation of Gla-Rich Protein (GRP) as a Novel Approach to Target Inflammation

Chronic inflammation is a major driver of chronic inflammatory diseases (CIDs), with a tremendous impact worldwide. Besides its function as a pathological calcification inhibitor, vitamin K-dependent protein Gla-rich protein (GRP) was shown to act as an anti-inflammatory agent independently of its gamma-carboxylation status. Although GRP’s therapeutic potential has been highlighted, its low solubility at physiological pH still constitutes a major challenge for its biomedical application. In this work, we produced fluorescein-labeled chitosan-tripolyphosphate nanoparticles containing non-carboxylated GRP (ucGRP) (FCNG) via ionotropic gelation, increasing its bioavailability, stability, and anti-inflammatory potential. The results indicate the nanosized nature of FCNG with PDI and a zeta potential suitable for biomedical applications. FCNG’s anti-inflammatory activity was studied in macrophage-differentiated THP1 cells, and in primary vascular smooth muscle cells and chondrocytes, inflamed with LPS, TNFα and IL-1β, respectively. In all these in vitro human cell systems, FCNG treatments resulted in increased intra and extracellular GRP levels, and decreased pro-inflammatory responses of target cells, by decreasing pro-inflammatory cytokines and inflammation mediators. These results suggest the retained anti-inflammatory bioactivity of ucGRP in FCNG, strengthening the potential use of ucGRP as an anti-inflammatory agent with a wide spectrum of application, and opening up perspectives for its therapeutic application in CIDs.

Multifunctional Nanocarriers for Lung Drug Delivery

Nanocarriers have been increasingly proposed for lung drug delivery applications. The strategy of combining the intrinsic and more general advantages of the nanostructures with specificities that improve the therapeutic outcomes of particular clinical situations is frequent. These include the surface engineering of the carriers by means of altering the material structure (i.e., chemical modifications), the addition of specific ligands so that predefined targets are reached, or even the tuning of the carrier properties to respond to specific stimuli. The devised strategies are mainly directed at three distinct areas of lung drug delivery, encompassing the delivery of proteins and protein-based materials, either for local or systemic application, the delivery of antibiotics, and the delivery of anticancer drugs-the latter two comprising local delivery approaches. This review addresses the applications of nanocarriers aimed at lung drug delivery of active biological and pharmaceutical ingredients, focusing with particular interest on nanocarriers that exhibit multifunctional properties. A final section addresses the expectations regarding the future use of nanocarriers in the area.

The role of stress-related physical confinement in the pathogenesis of acute gastric hemorrhage after alcohol instillation in rats

The combination of alcohol and stress have been considered producers of gastric hemorrhage both experimentally and in clinical observations. Since excessive alcohol intake often occurs in situations of severe emotional conflict and stress, it was decided to study the possible role of the latter in the etiology of gastric hemorrhage, up to now thought to be dependent only on alcohol. The study consists of 75 male Wistar rats divided into eight groups with seven to 14 animals each. They were submitted to fasting only, or to additional prolonged fasting, restraint-stress (physical confinement) for 17 hours and the oral administration of a single dose of 40% alcohol (1 ml/150 g of body weight). The stomachs were analyzed macroscopically and microscopically for the presence of gastric hemorrhage, and the following was observed; 1) only 10% of the rats submitted to a 25 hour fast either isolated or associated with 17 hours of physical confinement, demonstrated gastric hemorrhage; 2) after an eight hour fast, the administration of alcohol to the rats either sacrificed immediately or maintained for 17 hours, revealed gastric lesions in only 33.3% and 28.5% respectively, without significant statistical difference between the two groups (P > 0.05); 3) administration of alcohol prior to the 17 hour physical confinement revealed lesions in only 12.5% of the animals; 4) administration of alcohol to rats previously submitted to a 25 hour fast plus physical confinement for 17 hours, resulted in a significant number of hemorrhagic lesions (88.8%). This caused a statistical difference in the group compared to the others (P < 0.01). The results of this study led to the conclusion that stress (by prolonged physical confinement) was an important conditioning factor to the appearance of gastric hemorrhage when 40% alcohol was administered. It is possible that if the alcohol had been administered prior to the prolonged physical confinement its cytotoxic effect on the gastric mucosa might have been reduced.

Electromanometry of the rectosigmoid in colonic diverticulosis

In order to better understand the rectosigmoid motor activity in diverticular disease of the colon, we studied 186 patients, grouped according to their intestinal habit, the presence of diverticular disease and previous crisis of sigmoid diverticulitis. The intestinal habit was classified as: normal habit, irritable colon syndrome, diarrhea and constipation. The group of diverticulosis was classified by their intestinal habit and by diverticula localization (localized or generalized). The presence of systemic diseases or drug ingestion that could modify intestinal motility, were considered criteria for exclusion. The manometric study was preceded by food stimulus, with 650 kcal meal, by mechanic intestinal cleansing, with 500 ml of saline solution enema and by one hour resting period. A manometric catheter, was introduced by rectosigmoidoscopy, with open ended orifices situated at the sigmoid and upper rectum, respectively. The catheter was perfused by a capillary infusion system and the bowel pressures were registered for 30 minutes, in a thermal paper physiograph. We analyzed the % of activity, mean amplitude and motility index, by non parametric tests. No significant difference was observed between sexes. Difference or close to it were found for the groups with constipation, with or without diverticulosis, and for the latter in its subdivisions (localized, generalized and sigmoid diverticulitis). The rectal motor activity was similar in all groups. There was no difference for diverticulosis and its subdivision, when we take into account the several kinds of intestinal habits and the diverticula localization. The motility index averages showed low values for the sigmoid diverticulitis fact that suggests some dysfunction of this segment (hypocontractility). The key factor differentiating the groups was the presence of constipation and no influence was noted regarding the localization of diverticula or previous inflammatory process on intraluminal pressures. The fact that no difference was found in the mean amplitude or % of activity among patients with or without diverticulosis, suggests that the high pressures in a colonic segment, may not be responsible for the diverticular disease, and there must be other factors, besides motility, accounting for the development of the different forms of this disease.

[Single nocturnal dose of ranitidine in the treatment of duodenal ulcer: results of an open multicenter, comparative trial]

This prospective multicentric randomized open trial was designed to evaluate the efficacy of ranitidine 150 mg bid vs 300 mg nocte in the short-term (4 weeks) treatment of duodenal ulcer in 15 Brazilian centers. On the basis of a randomization table 190 patients with endoscopically confirmed duodenal ulcer were allocated to receive either ranitidine 150 mg bid (94 pts) or 300 mg nocte (96 pts). The 2 treatment groups were well matched for age, sex, duration of ulcer disease, number and size of ulcers, duration of current episode, intensity of ulcer pain, alcohol and coffee intake and smoking habits. They were endoscopically controlled at the end of the 4 weeks. At 4 weeks 78 of 94 patients (83.0%) had their ulcers healed with the 150 mg bid regimen as opposed to 79 of 96 patients (82.3%) allocated to the 300 mg nocte dosage. This difference was not statistically significant. Ulcer symptoms diminished with treatment in both groups. The tolerability and compliance was excellent in both groups. The results show that ranitidine 300 mg nocte is as effective in the short-term treatment of duodenal ulcer as ranitidine 150 mg bid. Considering the greater simplicity of administration enhancing patient compliance, the treatment with 300 mg nocte is preferable.

Teaching psychosomatic medicine

The authors want to present their experience over the last 20 years in teaching the psychosomatic approach to health professionals and students in their last years, i.e. medical doctors, psychologists, social workers, nurses and dentists. The teaching classes take up 2 years and their main function is to teach students psychosomatics as an approach, a proposal for an integral assistance in health care. They are aimed at emphasizing the human comprehension of pathology, trying to understand it within the scope of a historical and related process, without denying the organic reality of disease.

Gastrointestinal motility in constipation

This study included ten subjects with normal intestinal habits and 25 with constipation. Data were collected from X-rays of gastrointestinal transit times and from intraluminal pressures in the sigmoid and rectum using electromanometry. A comparison of the results led to the following conclusions: a) transit times to the cecum were essentially similar in both the control group and patients with constipation; b) the barium contrast arrived faster in the proximal sigmoid of patients with constipation compared to the control group; c) the mean of the total time of gastrointestinal emptying was slower in constipation; d) under unstimulated conditions, the electromanometry study of the sigmoid and rectum showed a higher motility index in constipation than in the control group; e) the high values of the percent activity was the most important element in the elevation of the motility index in constipation; f) the propulsion and retention activities of the colon were higher in constipation than in normals, as was demonstrated by radiologic and electromanometric studies.

[Emergencies in peptic gastroduodenal ulcers]

The authors present an objective review of the main emergencies regarding peptic ulcer disease, gastric and duodenal. The complications, perforation, bleeding and pyloric stenosis, are dealt with in detail, regarding diagnosis and best therapeutic orientation, either clinical or surgical.

Misoprostol in the treatment of duodenal ulcer. A multicenter double-blind placebo-controlled study

Patients with endoscopically documented duodenal ulcer participated in a double-blind, multicenter trial comparing placebo with misoprostol 100 micrograms administered q.i.d. for up to four weeks in the treatment of duodenal ulcer. Ulcers were examined endoscopically at two weeks and, if not healed, again at four weeks. Acetaminophen was permitted for pain relief. At four weeks, of 286 patients admitted to the study, the cumulative healing rate for the 227 evaluable patients was 64.9% for misoprostol and 47.4% for placebo (P = 0.008). Misoprostol was also significantly superior to placebo in promoting ulcer healing when all patients entering the study (intent-to-treat cohort) were compared (P = 0.018), and in a modified intent-to-treat cohort consisting of all patients whose final endoscopic results were known (P = 0.005). Ulcer symptoms were similar in both treatment groups, and most patients in both groups were pain free at the end of the first two weeks of treatment. Diarrhea was the most frequently reported adverse experience (8.5% for misoprostol and 3.5% for placebo). This symptom was mild and self-limiting in spite of continued use of misoprostol. We conclude that misoprostol 100 micrograms q.i.d. for four weeks is safe and effective in the healing of duodenal ulcers.

Gastrointestinal motility in normal subjects and patients with diverticulosis of the colon

Our study included 25 subjects, ten with normal intestinal habits and 15 with colonic diverticulosis. Data was collected from X-rays of gastrointestinal transit times and from intraluminal pressures in the sigmoid and rectum, using electromanometry. A comparison of the results led to the following conclusions: 1) transit times to the cecum were essentially similar in both the control subjects and patients with diverticulosis; 2) the barium contrast arrived twice as fast in the proximal sigmoid of patients with diverticulosis compared to the control group. Therefore, there is an increase in the transit between the cecum and sigmoid in individuals with diverticulosis of the colon; 3) the mean of the total time of gastrointestinal emptying is similar in both groups; 4) under unstimulated conditions, the electromanometric study of the sigmoid and rectum was similar in both groups; 5) the sigmoid region in patients with diverticulosis has a modulating transit capacity delaying it. This modulation was not reflected in the electromanometric study as an increase in motor activity.

[Crohn's disease of the duodenum associated with acute acalculous cholecystopathy]

Since the initial description of Crohn's disease (CD) located in the distal ileum, great number of cases has been observed, and we know that this disease can occur in any part of the digestive tube, from mouth to anus. The duodenal involvement is rare and no more than two hundred cases have been observed. A case of Crohn's disease located in the duodenum, with a severe acalculus cholecystitis, without intestinal involvement is presented. Radiological study showed a stenotic process in the first, second and third duodenal portion, later on confirmed by endoscopy. This was confirmed at surgery, when a gastrojejunostomy with truncal vagotomy, cholecystectomy, besides duodenum and liver biopsies were performed. The patient is asymptomatic four years after surgery. It is considered that bile reflux, resulting from involvement of Vater papilla by CD, is responsible factor of the biliary pathology.

[Hamartomatosis and adenomatosis of the colon]

The authors report five members of a family, having colonic polyposis, whose parents had adenomas that posteriorly degenerated to carcinoma, while sons had juvenile polyposis. Such aspects were considered as familial, evolutive and genetic. In contrast to adenomas, juvenile polyposis or hamartomas were always considered as benign lesions, with no susceptibility to malignancy. Nevertheless, these lesions must be considered as having degenerative potential at least similar to the originating tissue and, perhaps, even higher, once the sick tissue shows abnormal growth rate. These observations raise an important problem, namely, evaluating an eventual existence of malignancy among patients with juvenile polyposis which, if actually confirmed, could result in changes of its concepts and of its therapeutic approaches. The acknowledgement of the association between malignant potenial with genetics, could also result in better prevention for colonic cancer, once known its hereditary predisposition. The expectation of new cases among members of a same family should promote prevention before cancer appears. Thus, with this approach, the transcolonoscopic removal of polyps, mostly among families presenting high cancer potential, should avoid the sequence "adenoma-carcinoma".

[Treatment of bile duct diseases. Dyskinesias. Chronic inflammation]

The approach to the integrated diagnosis of the patient with biliary tract diseases is reviewed as a basis for the appropriate treatment, taking into account the functional disturbances and the organic elements including malformation, inflammation, infection, gallstone and neoplasia. The role of impaired emptying of the gallbladder is emphasized. This condition may give origin to inflammation of the gallbladder is emphasized. This condition may give origin to inflammation of the gallbladder which is caused by the irritative action of concentrated bile acids as a consequence of the stagnated bile in the gallbladder with poor emptying. Other consequences of bile stagnation in the gallbladder is gallstone formation and biliary infection by bacterias. Thus, increase of gallbladder emptying and of bile production are advised in the treatment of biliary diseases. Such two effects can be obtained by the diet using adequate amounts of vegetables, oils and eggs and by drugs such as choleretics. A new choleretic drug-the cicloxilic acid-was used in 102 patients, 48 out of them with gallstone and 54 without lithiasis. The following three actions of this drug were recorded: a decrease of gastrointestinal gaseousness; a decrease of abdominal discomfort and soreness, and a mild laxative effect with stool of less consistency.

[Psychosomatic medicine and psychoanalytic observation: considerations on the mechanism of symptom formation]

The clinical symptom, perceived at body level, such as pain, dyskinesia, circulatory changes (tachycardia, blushing, pallor) is intrinsic and simultaneous with parallel changes at the mind level, such as anxiety, sorrow, instability, joy, depression and shame. Therefore, it has to be distinguished within the symptom, the overt component - somatic alterations - and the latent component - changes in mental processes. Hence, the global psychosomatic nature is intrinsic to the clinical symptoms.

[Effect of cicloxilic acid on biliary dynamics]

This work was developed in order to estimate, with objective methods, the pharmacodynamic activities of a new choleretic and antilithogenic drug, the cicloxilic acid. It was determined the changes of daily biliary flow and bile composition in 8 patients with biliary system surgical intervention and "T" (Kehr) tube inserted. The cicloxilic acid was given in the dose of 240 mg/day. The results showed, after treatment, an emphasized middle volume increase of the excreted bile, as well as a significant decrease of the biliary cholesterol, while pH and density maintained constants. The results corroborated the pharmacodynamic activities given to cicloxilic acid as a "true" choleretic to be utilized in clinic situations where it's wished a biliary flow increase and the possibility to avoid a cholesterol lithiasis or relieve consequent disturbances.

[The effect of colchicine on liver function tests and hepatic fibrosis in patients with chronic active hepatitis: a study of 3 cases (author's transl)]

Three patients with chronic active hepatitis received Colchicine therapy, as an antifibrotic drug. The effect of this drug is analysed biochemically (serum albumin, total serum billirubin and amino-transferase aspartate) and histologically before and after colchicine therapy. Biochemical improvement was observed. No histological change was noted.