Structural and morphological characterization of hemozoin produced by Schistosoma mansoni and Rhodnius prolixus

Hemozoin (Hz) is a heme crystal produced upon the digestion of hemoglobin (Hb) by blood-feeding organisms as a main mechanism of heme disposal. The structure of Hz consists of heme dimers bound by reciprocal iron-carboxylate interactions and stabilized by hydrogen bonds. We have recently described heme crystals in the blood fluke, Schistosoma mansoni, and in the kissing bug, Rhodnius prolixus. Here, we characterized the structures and morphologies of the heme crystals from those two organisms and compared them to synthetic β-hematin (βH). Synchrotron radiation X-ray powder diffraction showed that all heme crystals share the same unit cell and structure. The heme crystals isolated from S. mansoni and R. prolixus consisted of very regular units assembled in multicrystalline spherical structures exhibiting remarkably distinct surface morphologies compared to βH. In both organisms, Hz formation occurs inside lipid droplet-like particles or in close association to phospholipid membranes. These results show, for the first time, the structural and morphological characterization of natural Hz samples obtained from these two blood-feeding organisms. Moreover, Hz formation occurring in close association to a hydrophobic environment seems to be a common trend for these organisms and may be crucial to produce very regular shaped phases, allowing the formation of multicrystalline assemblies in the guts of S. mansoni and R. prolixus.     

Changes in hemorheological parameters due to lead exposure in female rats

Lead is an ubiquitous metal in the environment that induces a broad range of physiological, biochemical and behavioral dysfunctions. The purpose of this study was to investigate its effects on blood parameters and blood viscosity. Female rats (14 Wistar-Albino type) were divided into a control and a lead exposed group. Both groups were fed with the same standard food, but lead acetate was added to the drinking water of the experimental group for 5 weeks. At the end of the experimental period, blood samples were drawn from the abdominal aorta of the anaesthetized animals. Hematocrit (Hct %), hemoglobin (Hb), and the number of erythrocytes were determined, blood viscosity was measured with a rotational viscometer, and the lead concentration in blood was analyzed by means of flame atomic absorption spectrometry. The erythrocyte count, Hb and Hct % of the lead exposed group were found to be significantly lower than in the control group (p<0.01). The blood viscosity level was significantly higher compared to the control group (p<0.01). It can be concluded that increased lead concentrations in blood impair certain hemorheological mechanisms and increase blood viscosity.     

Circulating levels of apoptotic markers and oxidative stress parameters in women with polycystic ovary syndrome: a case-controlled descriptive study

Context: Apoptotic dysregulation plays a role in the pathogenesis of polycystic ovary syndrome (PCOS).

Objective: To evaluate circulatory apoptotic markers and oxidative stress in patients with PCOS.

Materials and methods: Forty-four women with PCOS, and 44 healthy women as controls were enrolled in the study. Oxidative stress parameters and caspases levels were measured in serum.

Results: The caspase 9 level was significantly lower and related with oxidant status in patients with PCOS, while the circulating levels of caspases 3 and 7 were statistically similar in both groups.

Discussion: This study is the first report demonstrating the circulating levels of apoptotic markers and their relationship with oxidant status in PCOS.

Conclusion: The circulating caspase 9 and oxidant status might contribute to apoptotic dysregulation in PCOS.     

Effects of Chronic Light/Dark Cycle on Iron Zinc and Copper Levels in Different Brain Regions of Rats

In this study, we aimed to investigate whether chronic shift in light/dark cycle alters brain trace element concentrations. For this purpose, 20 male Wistar albino adult rats were weighed and randomly divided into three groups. The first group (n?=?6) was the control and had been subjected to 12/12-h light/dark cycle for 30?days. The second group (n?=?7) was subjected to 6/18-h light/dark cycle for 15?days, and the third group (n?=?7) was also subjected to 6/18-h light/dark cycle for 15?days and then returned to normal 12/12-h light/dark cycle for 15?days. When light/dark cycle protocols were completed, tissue specimens of the frontal lobe, temporal lobe, and brain stem were collected. Iron (Fe), zinc (Zn), and copper (Cu) concentrations of the frontal lobe, temporal lobe, and brain stem were determined by an atomic absorption spectrophotometer. When compared with controls, Fe levels of the temporal lobe significantly increased in 6/18-h light/dark cycle group (p?相似文献   

Molecular genetic diversity and association mapping of morphine content and agronomic traits in Turkish opium poppy (<Emphasis Type="Italic">Papaver somniferum</Emphasis>) germplasm

As the sole plant source of many potent alkaloids, opium poppy (Papaver somniferum L.) is an important medicinal crop. Nevertheless, few studies have characterized opium poppy germplasm with crop-specific molecular markers. Because Turkey is a diversity center for opium poppy, Turkish germplasm is a valuable genetic resource for association mapping studies aimed at identifying QTLs controlling morphine content and agronomic traits. In this study, the morphological diversity and molecular diversity of 103 Turkish opium poppy landraces and 15 cultivars were analyzed. Potentially useful morphological variation was observed for morphine content, plant height, and capsule index. However, the landraces exhibited limited breeding potential for stigma number, and seed and straw yields. Both morphological and molecular analyses showed distinct clustering of cultivars and landraces. In addition, a total of 164 SSR and 367 AFLP polymorphic loci were applied to an opium poppy association mapping panel composed of 95 opium poppy landraces which were grown for two seasons. One SSR and three AFLP loci were found to be significantly associated with morphine content (P < 0.01 and LD value (r ²) = 0.10–0.32), and six SSR and 14 AFLP loci were significantly associated with five agronomic traits (plant height, stigma number, capsule index, and seed and straw yields) (P < 0.01 and LD value (r ²) = 0.08–0.35). This is the first report of association mapping in this crop. The identified markers provide initial information for marker-assisted selection of important traits in opium poppy breeding.     

Local induction of acetylcholine receptor clustering in myotube cultures using microfluidic application of agrin

During neuromuscular synaptogenesis, the exchange of spatially localized signals between nerve and muscle initiates the coordinated focal accumulation of the acetylcholine (ACh) release machinery and the ACh receptors (AChRs). One of the key first steps is the release of the proteoglycan agrin focalized at the axon tip, which induces the clustering of AChRs on the postsynaptic membrane at the neuromuscular junction. The lack of a suitable method for focal application of agrin in myotube cultures has limited the majority of in vitro studies to the application of agrin baths. We used a microfluidic device and surface microengineering to focally stimulate muscle cells with agrin at a small portion of their membrane and at a time and position chosen by the user. The device is used to verify the hypothesis that focal application of agrin to the muscle cell membrane induces local aggregation of AChRs in differentiated C2C12 myotubes.     

Effects of erythropoietin and pentoxifylline on the oxidant and antioxidant systems in the experimental short bowel syndrome

In this study, we investigated the effects of erythropoietin (Epo), and pentoxifylline (Ptx) on the oxidant and antioxidant systems in the experimental short bowel syndrome. Spraque-Dawley rats were divided into four groups and all animals underwent 75% small bowel resection. Group E was treated with 500 IU kg(- 1) Epo subcutaneously (s.c.), group P with 50 mg kg(- 1) day(- 1) s.c. Ptx and group E+P with 500 IU kg(- 1) s.c. Epo plus 50 mg kg(- 1) day(- 1) s.c. Ptx for a period of 28 days. In group C, which is the control group, no drug treatment was given. At the end of 28 days the experimented rats were killed and ileum samples excised for biochemical and histopathological testing. Malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were determined in ileum homogenates. When compared to group C, the MDA and GSH-Px levels were significantly decreased (p < 0.05), but SOD activity was not changed (p > 0.05) in groups P and E+P, whereas both MDA and SOD and also GSH-Px activities were not changed significantly in group E (p > 0.05). The average villous length, crypt depth, muscular thickness and mucosal length were measured in all groups. The average crypt depth and mucosal length were statistically higher in the group P than group C (p < 0.001, p < 0.01, respectively). In addition, the crypt depth was statistically higher in both E and E+P groups as compared to group C (p < 0.001, p < 0.01, respectively). Therefore, our study indicates that Ptx may be more effective than Epo in reducing lipid peroxidation. Moreover, we considered that Ptx may give this protective effect by inhibiting the free oxygen radicals to a greater extent than developing the antioxidant capacity.     

S100A1 as a Potential Diagnostic Biomarker for Assessing Cardiotoxicity and Implications for the Chemotherapy of Certain Cancers

This study examined the value of blood marker S100A1 in detecting cardiotoxicity induced by chemotherapy agents; trastuzumab and lapatinib, in normal rat heart. The rats were divided into three groups: control (n = 8, no treatment), T (n = 8, one time ip treatment with 10 mg/kg trastuzumab) and L (n = 8, oral treatment with 100 mg/kg/day lapatinib for 7 days). The activities of oxidative stress parameters Malondialdehyde (MDA), Superoxide dismutase (SOD), Catalase (CAT) and Glutathione (GSH) were measured from the extracted cardiac tissues. The levels of troponinI and S100A1 expressions were measured from blood samples. All biomarkers responded to the treatments as they exhibited alterations from their normative values, validating the chemically induced cardiotoxicity. S100A1 expression attenuated significantly (75%), which made the sensitive detection of cardiotoxicity feasible. Assessment of cardiotoxicity with S100A1 may be a valuable alternative in clinical oncology of cancers in some organs such as breast and prostate, as they do not overexpress it to compete against.