Ultrastructure and heteromorphism of spermatozoa in five species of bugs (Pentatomidae: Heteroptera)

Pentatomidae is one of the largest Heteroptera families, comprising about 10% of the species estimated for the suborder. In spite of existing studies, doubts remain regarding the systematics of Pentatomomorpha. In this study, five species of Pentatomidae spermatozoa were examined to achieve characteristics that enable inferences in the phylogeny of the group and in behavioral issues associated with the presence of polymorphisms. Spermatozoa polymorphisms, characterized by two classes of sizes, are found in Podisus nigrispinus, Podisus distinctus, and Brontocoris tabidus, whereas Thynacanta marginata (Dallas) and Supputius cincticeps have single-size spermatozoa. The head region consists of an acrosome, a nucleus, and part of the centriolar adjunct. In the more anterior region, the nucleus is parallel to the centriolar adjunct. In the nucleus-flagellum transition region, the nucleus overlaps the anterior region of the mitochondrial derivatives, just above the axoneme. The mitochondrial derivatives and the axoneme run the entire extent of the flagellum. In species in which the spermatozoa are polymorphic, the larger spermatozoa have derivatives mitochondrial approximately 3-fold larger than the smaller spermatozoa. Characteristics derived from the morphology of spermatozoa indicate synapomorphies and are promising for systematic studies.     

Phagocytosis of spermatozoa by epithelial cells in the vagina of the lizard Hemidactylus mabouia (Reptilia, Squamata)

Hemidactylus mabouia is an Africa oviparous lizard that is now distributed on other continents and has been introduced to Brazil. In the majority of reptiles, the females have the ability to store spermatozoa in specialized regions of the genital tract. Considering that in H. mabouia the storage of spermatozoa is restricted to the region of the uterine tube, in this study we utilized optical and transmission electron microscopy to investigate the processes related to the large number of spermatozoa in the vagina. Although it was possible to visualize spermatozoa in the vagina, an ultrastructural analysis of the region revealed that significant phagocytosis occurs, which is mediated by the epithelial cells. Such a process indicates that the anterior portion of the vagina is related to the elimination of supernumerary or deficient spermatozoa and not storage.     

Antimycobacterial activity of salicylanilide benzenesulfonates

A series of eighteen novel esters of salicylanilides with benzenesulfonic acid were designed, synthesized and characterized by IR, 1H-NMR and 13C-NMR. They were evaluated in vitro as potential antimycobacterial agents towards Mycobacterium tuberculosis, Mycobacterium avium and two strains of Mycobacterium kansasii. In general, the minimum inhibitory concentrations range from 1 to 500 μmol/L. The most active compound against M. tuberculosis was 4-chloro-2-(4-(trifluoromethyl)phenylcarbamoyl)-phenyl benzenesulfonate, with MIC of 1 μmol/L and towards M. kansasii its isomer 5-chloro-2-(4-(trifluoromethyl)phenylcarbamoyl)phenyl benzenesulfonate (MIC of 2-4 μmol/L). M. avium was the less susceptible strain. However, generally, salicylanilide benzenesulfonates did not surpass the activity of other salicylanilide esters with carboxylic acids.     

Synthesis and Antitubercular Evaluation of N‐Arylpyrazine and N,N′‐Alkyl‐diylpyrazine‐2‐carboxamide Derivatives

Two series of pyrazinamide (PZA) derivatives have been synthesized and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis H37Rv. Some compounds exhibited minimum inhibitory concentration activity of 50–100 μg/mL, greater than the first line antituberculosis drug PZA in Alamar Blue assay (>100 μg/mL). The obtained activities can be considered promising results, which characterizes these compounds as good start points to development of new antitubercular agents.     

1H and 13C NMR spectral assignments of four dammarane triterpenoids from carnauba wax

The phytochemical investigation of carnauba wax led to the isolation of three new dammarane triterpenoids 1, 2 and 4, together with the known triterpene 3. The structures of the new compounds were determined by 1D and 2D NMR spectroscopy and by comparison with published data for closely related compounds.     

Niobium (V) peroxocomplexes as a catalyst of oxidation of methylphenylsulphide by hydroperoxide

The electrospray ionization-mass spectrometry (ESI-MS) method has been used for determination of the structure of niobium peroxocomplexes. The formation of mono- and bisperoxocomplexes has been established. These complexes contain Schiff bases and 8-quinolinol as ligands. Trisperoxocomplexes are formed when pyridine and 1,10-phenanthroline are used. Peroxocomplexes with Schiff bases as ligands has shown a high activity as catalysts in the methylphenylsulphide oxidation.     

Application of thermal analysis to the study of antituberculosis drugs–excipient compatibility

First-line drugs (rifampicin, RIF; isoniazid, INH; ethambutol, ETA; and pyrazinamide, PZA) recommended in conventional treatment of tuberculosis were analyzed in 1:1 w/w binary mixtures with microcrystalline cellulose MC 101 (CEL) and lactose supertab^® (LAC) by differential scanning calorimetry (DSC), thermogravimetry (TG), differential thermal analysis (DTA), and Fourier transformed infrared analysis (FTIR) as part of development of fixed dose combination (FDC) tablets. Evidence of interaction between drug and pharmaceutical excipients was supposed when peaks disappearance or shifting were observed on DTA and DSC curves, as well as decreasing of decomposition temperature onset and TG profiles, comparing to pure species data submitted to the same conditions. LAC was showed to interact with RIF (absence of drug fusion and recrystallization events on DSC/DTA curves); INH (thermal events of the mixtures different from those observed for drug and excipient pure in DSC/DTA curves); PZA (decrease on drug fusion peak in DSC/DTA curves), and ETA (shift on drug onset fusion and absence of pure LAC events on DSC/DTA curves). In all cases, an important decrease on the temperature of drug decomposition was verified for the mixtures (TG analysis). However, FTIR analysis showed good correlation between theoretical and experimental drug-LAC spectra except for INH–LAC mixture, evidencing high incompatibility between these two species and suggesting that those interactions with PZA and RIF were thermally induced. No evidence of incompatibilities in CEL mixtures was observed to any of the four-studied drugs.     

Effect of Diets,Familial History,and Alternative Therapies on Genomic Instability of Breast Cancer Patients

This study evaluates a correlation between family history, micronutrients intake, and alternative therapies with genetic instability, before and during breast cancer treatment. For this study, a total of 150 women were selected. Among those, 50 women were breast cancer patients on chemotherapy, while 50 breast cancer patients were on radiotherapy, and 50 were healthy females. All the participants signed the informed consent form and answered the public health questionnaire. Samples of buccal epithelial and peripheral blood cells were collected and analyzed through micronucleus and comet assays. The cells were evaluated for apoptosis and DNA damage. Results showed the association of patients’ family history with an increase in toxicogenetic damage before and during cancer therapy. On the other hand, patients with late-onset cancer also presented genetic instability before and during therapy, along with those who did not take sufficient vegetables and alternative therapies. A positive correlation was observed between the genetic instability and alternative therapies, while inverse correlation was recorded with the vegetable consumption. Results clearly explain that the nutritional aspects and alternative therapies influence the genetic instability before and during cancer therapies especially in radiotherapy treated patients. Our data could be used for the monitoring therapies and management of breast cancer patients.

     

Separation of niobium and tantalum by extraction chromatography with bis(2-ethylhexyl)phosphoric acid

A novel method is developed for the reversed-phase extractive chromatographic separation of niobium and tantalum with bis(2-ethylhexyl)phosphoric acid. Niobium is extracted from 1-10M hydrochloric acid and can be stripped with 3M sulphuric acid containing 2% hydrogen peroxide. Tantalum is extracted from 0.1-2M hydrochloric acid and can be stripped with 0.1M hydrochloric acid containing 2M tartaric acid. It is possible to separate niobium and tantalum, in different ratios, from multicomponent mixtures.