Chitosan thread in the healing of the cecal wall of rabbits (Oryctolagus cuniculus) submitted to cecorrhaphy.

The development and evaluation of synthesis materials are crucial to reducing the morbidity and magnitude of post-enterorrhaphy surgical complications. Despite the possibility of production, chitosan thread has not yet been used in enterorrhaphy, and its effects on intestinal healing have not been evaluated. Therefore, this study aimed to evaluate the effects of chitosan thread on the intestinal wall repair of rabbits submitted to cecorrhaphy. For this, 42 rabbits were allocated into two groups with 21 animals. One group was submitted to cecorrhaphy with chitosan suture thread (CG) and the other with poliglecaprone suture thread (PG). The occurrence of postoperative complications, the intensity of edema, cellular response, formation of granulation tissue, as well as the deposition and maturation of collagen fibers, and the intensity of vascular endothelial growth factor (VEGF-α) expression, were evaluated during the intestinal wall repair process. The evaluations occurred on the 5th, 15th, and 25th postoperative (PO) days. The animals did not develop peritonitis, but adherence was observed in six animals from CG and seven from PG, with no difference between groups. The polymorphonuclear infiltrate showed higher intensity and higher amount of type III collagen fibers in CG on the 15th PO day. In contrast, a lower amount of type I collagen fibers was observed in CG samples on the 25th PO day. Therefore, the chitosan thread used for cecorrhaphy in rabbits results in minimal postoperative complications, presents biocompatibility, and bioactively assists the tissue repair process of the cecal wall, inducing minimal tissue reaction, stimulating the deposition of type III collagen fibers in the proliferative phase, with sustained VEGF-α expression, but with reduced deposition of type I fibers, indicating a delay in collagen maturation.

Coronavirus disease 2019 and stroke in Iran: a case series and effects on stroke admissions.

OBJECTIVE: The coronavirus disease 2019 pandemic has affected healthcare systems around the globe and massively impacted patients with various non-infectious, life-threatening conditions. Stroke is a major neurological disease contributing to death and disability worldwide, and is still an ongoing issue during the pandemic. Here we investigate the impact of the coronavirus disease 2019 outbreak on stroke manifestations, treatment courses, the outcome of stroke patients, and the hospitalization rate in a referral center for stroke management in Tehran, Iran. METHODS: We extracted data regarding 31 stroke patients (10 patients with laboratory-confirmed coronavirus disease 2019) and compared the demographic and pathological characteristics of the patients with or without coronavirus disease 2019 infection. The association of demographic/pathological characteristics of stroke patients during the coronavirus disease 2019 pandemic and a corresponding period during the previous year (49 patients) and an earlier period during the same year as the pandemic (50 patients) was also evaluated. RESULTS: The absolute number of admissions decreased about 40% during the coronavirus disease 2019 pandemic. Except for the stroke severity (P = 0.002), there were no significant changes in the demographic and pathological characteristics of the stroke patients during the three studied periods. A significantly higher mean of age (75.60 ± 9.54 versus 60.86 ± 18.45; P = 0.007), a significant difference in the type of stroke (P = 0.046), and significantly higher stroke severity (P = 0.024) were observed in stroke patients with coronavirus disease 2019 compared with those of stroke patients without coronavirus disease 2019. Treatment approaches, duration of hospitalization, and mortality rates did not differ significantly. CONCLUSIONS: This report shows that the pandemic caused the number of acute stroke admissions to plummet compared to other periods. Although the pandemic did not affect the treatment plans and care of the patients, stroke cases with coronavirus disease 2019 had higher age, more large vessel ischemic stroke, and more severe stroke. Further studies are urgently needed to realize the probable interaction of the coronavirus disease 2019 pandemic and the neurologic disease.

The photoprotective and anti-inflammatory activity of red propolis extract in rats.

The negative effects triggered by ultraviolet radiation, such as premature aging and carcinogenesis, have motivated several studies on photoprotection. Recent strategies for photoprotection have included the incorporation of natural antioxidant and anti-inflammatory compounds, such as flavonoids, into sunscreens and the oral administration of natural antioxidant extracts. Brazilian Red propolis extract contains isoflavonoids with antioxidant and anti-inflammatory activities. Here, we investigate the photoprotective effects of orally- or topically-administered formulations containing hydroalcoholic extract of red propolis (HERP) in a rodent model. HERP showed markers identified as: daidzein (4.68 µg/mL), formononetin (31.81 µg/mL) and biochanin A (9.58 µg/mL). A fourth peak was found in the chromatogram but was not identified. The antioxidant activity of HERP was calculated to be 3.07 mmol Trolox/g and 2.13 mmol Trolox/g, respectively. Topical HERP exerted a protective action against UVB radiation, which was similar to that exerted by oxybenzone filter. Oral HERP as an adjuvant treatment did not increase sunburn protection. However, the oral administration of HERP presented chemoprotective and anti-inflammatory activity (p < 0.05) similar or better than Polypodium leucotomos oral treatment (positive control). In conclusion, topical administration of HERP has photoprotective activity in a murine model and the mechanisms of protection can be related to the antioxidant and anti-inflammatory characteristics of HERP compounds.

A proteomic road to acquire an accurate serological diagnosis for human tegumentary leishmaniasis.

Diagnostic tools are important for clinical management and epidemiological evaluation of Tegumentary (TL) and Visceral (VL) Leishmaniasis. Serology is not frequently used for the diagnosis of the TL form because low antibody titers and cross-reaction with VL. Therefore, it is crucial to identify specific and immunogenic antigens from species associated with the TL form. Here we employed a proteomic approach coupled to an in silico analysis and identified the most abundant and immunogenic proteins from Leishmania amazonensis, Leishmania braziliensis and Leishmania infantum. Of 16 species specific proteins, nine were from the species causative of the TL form (L. amazonensis and L. braziliensis). In silico analysis revealed 18 B-cell epitopes with 0% similarity to Trypanosoma cruzi orthologs and, therefore, less likely to crossreact with sera of patients with Chagas disease. Two proteins reacted exclusively with serum from TL patients and presented several B-cell epitopes without similarity to T. cruzi orthologs: the hypothetical protein GI 134063939 and the metallo-peptidase Clan MA(E)-Family M3. The immunoassay revealed nine peptides with strong reactivity to sera from TL patients. These proteins and peptides may be good candidates to improve the specificity and sensibility of serological tests aiming to diagnose the TL of this neglected human disease. BIOLOGICAL SIGNIFICANCE: As no gold-standard test for tegumentary leishmaniasis (TL) exists, a combination of different diagnostic techniques is often necessary to obtain precise results. Thus, the identification of species-specific, highly immunogenic and abundant proteins that stimulate the humoral immune response in the host should help in the development of serological tests for human TL. Herein we searched for these potential antigens in Leishmania species related to American Leishmaniasis (L. amazonensis, L. braziliensis and L. infantum). To this end, we employed an immunoproteomic approach using proteins from these Leishmania species and sera from TL and Visceral Leishmaniasis (VL) patients. Our study unveils specific proteins and peptides that may represent antigens that will help the efforts to improve the accuracy of serological tests to diagnose the TL form.

Immunoproteomic and bioinformatic approaches to identify secreted Leishmania amazonensis, L. braziliensis, and L. infantum proteins with specific reactivity using canine serum.

Leishmania spp have a wide range of hosts, and each host can harbor several Leishmania species. Dogs, for example, are frequently infected by Leishmania infantum, where they constitute its main reservoir, but they also serve as hosts for L. braziliensis and L. amazonensis. Serological tests for antibody detection are valuable tools for diagnosis of L. infantum infection due to the high levels of antibodies induced, unlike what is observed in L. amazonensis and L. braziliensis infections. Likewise, serology-based antigen-detection can be useful as an approach to diagnose any Leishmania species infection using different corporal fluid samples. Immunogenic and secreted proteins constitute powerful targets for diagnostic methods in antigen detection. As such, we performed immunoproteomic (2-DE, western blot and mass spectrometry) and bioinformatic screening to search for reactive and secreted proteins from L. amazonensis, L. braziliensis, and L. infantum. Twenty-eight non-redundant proteins were identified, among which, six were reactive only in L. amazonensis extracts, 10 in L. braziliensis extracts, and seven in L. infantum extracts. After bioinformatic analysis, seven proteins were predicted to be secreted, two of which were reactive only in L. amazonensis extracts (52kDa PDI and the glucose-regulated protein 78), one in L. braziliensis extracts (pyruvate dehydrogenase E1 beta subunit) and three in L. infantum extracts (two conserved hypothetical proteins and elongation factor 1-beta). We propose that proteins can be suitable targets for diagnostic methods based on antigen detection.

Aqueous extract of Chrysobalanus icaco leaves, in lower doses, prevent fat gain in obese high-fat fed mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Due to the rise in obesity, the necessity for resources and treatments that could reduce the morbidity and mortality associated to this pandemia has emerged. The development of new anti-obesity drugs through herbal sources has been increasing in the past decades which are being used not only as medicine but also as food supplements. Previous studies with the aqueous extract of Chrysobalanus icaco L (AECI) have demonstrated activity on lowering blood glucose levels and body weight. AIM OF THE STUDY: Investigate C. icaco effects in overall adiposity and glycemic homeostasis. MATERIAL AND METHODS: C57BL/6J mice were randomly assigned to standard chow (SC) or high-fat diet (HFD) and treated with AECI in 0.35mg/mL or 0.7mg/mL concentrations ad libitum. Food intake, feed efficiency, metabolic efficiency, body, fat pads and gastrocnemius weight, adiposity index, serum lipids, fecal lipid excretion, locomotor activity in the open field test and insulin and glucose tolerance tests were analyzed and compared. The major components of the extract were demonstrated through HPLC and its antioxidant activity analyzed through DPPH and lipid peroxidation. RESULTS: The AECI in the 0.35mg/mL concentration did not affect food intake or body weight. However, it promoted lower adipose tissue gain, TG levels, and fecal lipid excretion, increased locomotor activity and lean mass weight, and normalized insulin sensitivity and glucose tolerance. Moreover, AECI showed the presence of myricetin 3-O-glucuronide, rutin, quercitrin and myricitrin and demonstrated high-antioxidant activity. CONCLUSIONS: AECI in lower concentrations can prevent fat storage or enhance fat utilization through the increase of locomotor activity. Also, this reinforces its ability to maintain glucose homeostasis through the normalization of insulin sensitivity and glucose tolerance despite the high-fat diet intake. These activities could be associated to the extract's polyphenol content.