The number of pregnancies is a risk factor for Alzheimer's disease

Epidemiological data show a higher prevalence of late-onset Alzheimer's disease (AD) in women. The estrogenic deficiency in the post-menopausal period is suspected to be the cause of the gender-related risk of the disease, but studies on the estrogenic therapy and occurrence of AD were not consistent and sometimes contradicting. The aim of this study is to investigate whether a higher exposure to endogenous estrogens is associated with lower risk of dementia or not. Two hundred and four AD patients and 201 control women were considered. By interviews, we evaluated different variables, indirectly correlated to estrogenic natural exposure, as well as educational level and head trauma. These data were correlated in the AD group with the disease progression, as well as with the age at onset. Unexpectedly, we found a significant higher number of pregnancies in the AD than in the control group. Within the AD cases, the number of lifetime pregnancies is related to an earlier onset of the disease. As previously reported, we confirmed that the educational level is a protective factor and that major head trauma represents a risk factor in developing AD. The higher number of pregnancies and a less frequency of nulliparous women, indirectly relate the AD group to a higher estro-progestinic exposure. These findings suggest that it is the increase of progesterone or estrogens level--and not the estrogens decrease, as previously indicated by other authors--that could play a role in the Alzheimer's pathology.

In vitro evaluation of the protective effects of plant extracts against amyloid-beta peptide-induced toxicity in human neuroblastoma SH-SY5Y cells

Alzheimer's disease (AD) is the most common form of dementia and has no cure. Therapeutic strategies focusing on the reduction of oxidative stress, modulation of amyloid-beta (Aβ) toxicity and inhibition of tau protein hyperphosphorylation are warranted to avoid the development and progression of AD. The aim of this study was to screen the crude extracts (CEs) and ethyl-acetate fractions (EAFs) of Guazuma ulmifolia, Limonium brasiliense, Paullinia cupana, Poincianella pluviosa, Stryphnodendron adstringens and Trichilia catigua using preliminary in vitro bioassays (acetylcholinesterase inhibition, antioxidant activity and total polyphenol content) to select extracts/fractions and assess their protective effects against Aβ25-35 toxicity in SH-SY5Y cells. The effect of the EAF of S. adstringens on mitochondrial membrane potential, lipid peroxidation, superoxide production and mRNA expression of 10 genes related to AD was also evaluated and the electropherogram fingerprints of EAFs were established by capillary electrophoresis. Chemometric tools were used to correlate the in vitro activities of the samples with their potential to be evaluated against AD and to divide extracts/fractions into four clusters. Pretreatment with the EAFs grouped in cluster 1 (S. adstringens, P. pluviosa and L. brasiliense) protected SH-SY5Y cells from Aβ25-35-induced toxicity. The EAF of S. adstringens at 15.62 μg/mL was able completely to inhibit the mitochondrial depolarization (69%), superoxide production (49%) and Aβ25-35-induced lipid peroxidation (35%). With respect to mRNA expression, the EAF of S. adstringens also prevented the MAPT mRNA overexpression (expression ratio of 2.387x) induced by Aβ25-35, which may be related to tau protein hyperphosphorylation. This is the first time that the neuroprotective effects of these fractions have been demonstrated and that the electropherogram fingerprints for the EAFs of G. ulmifolia, L. brasiliense, P. cupana, P. pluviosa and S. adstringens have been established. The study expands knowledge of the in vitro protective effects and quality control of the evaluated fractions.

Pheophorbide a, a compound isolated from the leaves of Arrabidaea chica, induces photodynamic inactivation of Trypanosoma cruzi

BACKGROUND

Approximately 6-7 million people are infected with Trypanosoma cruzi, the etiological agent of Chagas' disease. Only two therapeutic compounds have been found to be useful against this disease: nifurtimox and benznidazole. These drugs have been effective in the acute phase of the disease but less effective in the chronic phase; they also have many side effects. Thus, the search for new compounds with trypanocidal action is necessary. Natural products can be the source of many important substances for the development of drugs to treat this infection. The present study evaluated the biological activity of an extract and fractions of Arrabidaea chica against T. cruzi and observed morphological and ultrastructural characteristics of parasites exposed to the isolated compound pheophorbide a.

METHODS

The crude hydroethanolic extract of A. chica was prepared. Fractions were obtained by partition and separated by liquid chromatography.

RESULTS

We observed a progressive increase in activity against epimastigote, trypomastigote, and amastigote forms of the parasite over the course of the fractionation process. Interestingly, we isolated a compound known as a photosensitizer that is used in photodynamic therapy. This method of treatment involving a photosensitizer, activation light and molecular oxygen is of great importance due to its selectivity. Pheophorbide a had activity against the protozoan in the presence of light and caused morphological and ultrastructural changes, demonstrating its potential in photodynamic therapy.

CONCLUSIONS

Based on the ability of pheophorbide a to eliminate bloodstream forms of T. cruzi, we suggest its use in blood banks for hemoprophylaxis.

Application and evaluation of propolis, the natural antioxidant in Italian-type salami

Summary This study aimed to characterize propolis with respect to its antioxidant activity and apply it to the elaboration of Italian-type salami. A propolis sample was collected and subjected to chemical and physicochemical characterization and its antioxidant capacity determined. Four salami formulations were developed: F1 (no antioxidants); F2 (addition of 0.01% BHT); F3 (addition of 0.01% propolis) and F4 (addition of 0.05% propolis). The salamis were evaluated with respect to their physicochemical properties and lipid oxidation. The characterization of the propolis showed a high level of waxes and low levels of phenolic compounds and flavonoids, although in sufficient quantity to prove their antioxidant activity. The Italian-type salamis showed moisture, protein and lipid contents which conformed to the limits preconized by Brazilian legislation. The F4 formulation (0.05% propolis) showed a better result when compared to the formulations F3 (0.01% propolis) and F1 (no antioxidant). However, formulation F2 (0.01% BHT) showed the lowest value of lipid oxidation. The results showed that propolis inhibits oxidative action and can be added to meat products as a natural antioxidant.

Genetic and molecular alterations in rhabdomyosarcoma: mRNA overexpression of MCL1 and MAP2K4 genes

Rhabdomyosarcoma, the most common soft tissue sarcoma in childhood, belongs to the small round cell tumor family and is classified according to its histopathological features as embryonal, alveolar and pleomorphic. In this study we propose to explore genetic alterations involved in rhabdomyosarcoma tumorigenesis and assess the level of mRNA gene expression of controlling survival signalling pathways. For genetic and molecular analysis, array-based comparative genomic hybridization, combined with Real Time PCR using the comparative method, was performed on 14 primary well-characterized human primary rhabdomyosarcomas. Multiple changes affecting chromosome arms were detected in all cases, including gain or loss of specific regions harbouring cancer progression-associated genes. Evaluation of mRNA levels showed in the majority of cases overexpression of MCL1 and MAP2K4 genes, both involved in cell viability regulation. Our findings on rhabdomyosarcoma samples showed multiple copy number alterations in chromosome regions implicated in malignancy progression and indicated a strong expression of MAP2K4 and MCL1 genes, both involved in different biological functions of complicated signalling pathways.

Stem bark extract of Poincianella pluviosa incorporated in polymer film: Evaluation of wound healing and anti-staphylococcal activities

Poincianella pluviosa has already been described as capable of healing skin wounds. In an attempt to prolong contact of the drug with the wound, it was proposed in this study to evaluate wound healing using a crude extract (CE) of P. pluviosa incorporated in carboxymethylcellulose polymer films. The chromatographic profile of the semipurified fraction of P. pluviosa was evaluated by ultra-high performance liquid chromatography (UHPLC), confirming the compounds gallic acid, geraniin, and ellagic acid. The films were evaluated for their physical and mechanical properties, water vapor permeability, moisture absorption capacity, and FTIR spectroscopy. For in vivo experiments, wounds were made on the back of rats and treated daily for 4, 7, 10, or 14 days with film containing CE or control film. At the end of each period, skin permeation analysis and histological analysis were made using re-epithelialisation, cell proliferation, and collagen formation. Statistical significance was determined by GraphPad Prism using t test and Mann-Whitney test. Anti-staphylococcal activity was evaluated with standard strains of Staphylococcus aureus, methicillin-resistant, and coagulase negative. It was demonstrated that the presence of CE in the films increased the capacity to absorb water and decreased resistance and permeability. The CE of the film permeated the skin, reaching the dermis and was able to influence re-epithelisation, cell proliferation, and collagen formation. Satisfactory results were observed against S. aureus strains, particularly coagulase negative. Films with CE of P. pluviosa can be an alternative in the wound healing, protecting against opportunistic infections and giving comfort to the patient.

Cytotoxicity of extracts and compounds isolated from Croton echioides in animal tumor cell (HTC)

The search for compounds with anticancer effects is of paramount importance today due to the high incidence of the disease. The Euphorbiaceae family is known for having compounds with therapeutic properties, one of its genera being Croton. It has several species, which contain compounds already known for their biological activities, presenting anti-inflammatory, antimicrobial and anticancer properties. Thus, the cytotoxicity/antiproliferative activity of semi-purified fractions and compounds isolated from Croton echioides in liver tumor cells of Rattus norvegicus (HTC) was evaluated by the MTT test. The semi-purified fractions showed cytotoxicity at concentrations above 200 µg/mL, at 24, 48 and 72 hours, reaching cell viability of 24.78% [400 µg/mL] at 24 hours, 12.79% [500 µg/mL] at 48 hours and 10.57% [300 µg/mL] at 72 hours. For the isolated compounds, lupeol had a cytotoxic effect in all concentrations (1, 5, 10, 15, 20, 40, 60, 80 and 100 µg/mL) and tested times (24, 48 and 72 hours), reaching minimum viability of 4.37% [100 µg/mL], within 72 hours. The clerodan diterpenes CEH-1 and CEH-4 also showed antiproliferative activity, with minimum viability of 36.19% [100 µg/mL] over 72 hours and 21.33% [100 µg/mL] over 48 hours, respectively. However, the clerodan diterpenes CEH-2 and CEH-3 did not shows a cytotoxic effect for HTC cells. Thus, there is a cytotoxic/antiproliferative potential of C. echioides against tumor cells, with targeted to mitochondrial enzymes, associated with cell proliferation, indicating that this species deserves prominence in the search for new molecules for the treatment of cancer.

Method development and validation for analysis of microencapsulated cyanidin-3-O-rutinoside in dairy samples containing juçara palm fruit by high-performance liquid chromatography

Euterpe edulis is a plant native of Brazil and popularly known as juçara. The aim of this study was to develop and validate an analytical method using high-performance liquid chromatography (HPLC) of juçara crude extracts (JCEs) and to evaluate dairy products containing free and microencapsulated extracts. The validated analytical method for JCE was performed using cyanidin-3-O-rutinoside (C3R - isolated and identified as major component from JCE) as a reference: linearity was obtained using ten concentrations between 25 and 250 μg mL-1 (R2  = 0.994); limits of detection and quantification were 19.04 μg mL-1 and 57.7 μg mL-1 respectively; accuracy (relative standard deviation) was <5%; recovery was 104.85 μg mL-1 ; and the method is robust. Physicochemical analyses of the dairy products were evaluated using colour, pH, and concentration of anthocyanins using HPLC calculated as C3R over 21 days of storage. The pH remained stable until the end of the test. The colour and the concentration of anthocyanins remained stable for 9 days. C3R was isolated, the HPLC method was developed and validated, and the colour stability was not altered until 9 days. © 2023 Society of Chemical Industry.

Cytotoxicity of isolated compounds from Picrasma crenata (Vell.) Engl. in animal tumor cell (HTC)

The study aim was to evaluate the cytotoxic activity, using the MTT test [3-(4,5-Dimethilthiazol-2-yl)-2,5-diphenil tetrazolium bromide], from the crude extract of Picrasma crenata (Pau Tenente) and its isolated compounds, quassin and parain, in culture of rat liver tumor cells (HTC). The test was carried out exposing the cells for 24, 48 and 72 hours to concentrations of 5, 10, 50, 100, 200, 300, 400, 500 and 1000 μg of crude extract of Pau Tenente/mL of culture medium and 1, 5, 10, 15, 20, 40, 60, 80 and 100 μg of quassin or parain compounds/mL of culture medium. The absorbances averages results obtained showed that the crude extract did not present cytotoxicity for the HTC cells in all the concentrations and evaluated times. For quassin, the concentrations of 80 and 100 μg/mL were cytotoxic, after 72 hours of treatment. For parain, the concentrations of 1, 5, 20, 40, 60, 80 and 100 µg/mL, in 72 hours, were cytotoxic, revealing a new activity for this compound. Thus, the results demonstrate a first indication of the cytotoxic activity of compounds quassin and parain, adding an important social and economic value to them, and may have application in future research and in pharmaceutical industry.

[Conservative surgical treatment of lung cancer: the "sleeve resection". Case contribution]

A series of 19 upper right lobectomies with resection and anastomosis of the principal bronchus carried out since 1975 at the 2nd Surgery Division, S. Luigi Gonzaga Hospital is described. An account is given of the carcinogenic risk, the endoscopic aspects, and the intraoperative picture in the various cases, and the long-term survivals, compatible with the time when the operation was performed. A brief description is also given of the technique employed, namely Sleeve Resection instead of the usual cuneiform approach. The reasons for this choice are explained. Lastly, from what is indicated it appears that right upper lobectomy with resection and anastomosis of the main bronchus is a very efficacious and very probably radical method in any cases where the neoplastic site should make right pneumonectomy necessary, but this is barred on the patient's functional status.