Phytochemical observation and antibacterial activity of Cyperus esculentus L

In the present study various extracts of Cyperus esculentus L. such as acetone, 50% ethanol, chloroform and petroleum ether were evaluated for their antibacterial activity against several human pathogens such as Escherichia coli, Staphylococcus aureus, Salmonella sp, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa and Citrobacter freundii, by using disc diffusion method. The activity of the samples were compared with that of standard antibiotics. The qualitative phytochemical analysis was also carried out with all the extracts of the sample. Of all the extracts 50% ethanol and acetone extract were found to be rich in phytochemicals such as alkaloids, flavonoids, phenols, tannins, steroids, terpenoids and glycosides. Acetone extract showed highest inhibitory activity against S.aureus, ILpneumoniae and P.vulgaris. 50% ethanolic extract showed maximum activity against E.coli, S.aureus and Salmonella sp. Chloroform extract maximally inhibited the growth of S.aureus whereas, petroleum ether extract showed positive results against Salmonella sp respectively. All extracts were sensitive to C. freundii.

Distinct but redundant expression of the Frizzled Wnt receptor genes at signaling centers of the developing mouse brain

The establishment of the regional subdivisions of the vertebrate CNS is accomplished through the activity of different neuroepithelial organizing centers. The wingless/int (Wnt) family of secreted glycoproteins, among other factors, plays a crucial role in signaling from these centers. Wnt1 secreted from the boundary between the mid- and hindbrain, for instance, controls the development of this brain region and of associated neuronal populations. Different Wnts secreted from the caudomedial pallium, the cortical hem, pattern the adjacent hippocampal field. The first step in Wnt signal transduction is binding of the Wnt ligand to its receptors, the seven-pass transmembrane Frizzled proteins. Inactivation of different Frizzled genes in mice have revealed an extensive functional redundancy between these receptors. In order to discriminate between a possible participation of different Frizzled receptors in the transduction of Wnt signals at the mid-/hindbrain boundary and the cortical hem, we have performed a detailed expression study of the 10 known murine Frizzled genes at crucial stages of mouse embryonic development. Our analysis reveals a highly dynamic yet distinct expression pattern of individual Frizzled genes in the anterior neural tube of the developing mouse embryo. The overlapping spatio-temporal expression of at least two and up to six Frizzled genes in any region of the developing mouse brain, however, also suggests a vast functional redundancy of the murine Frizzled receptors. This redundancy has to be taken into consideration for future analyses of Frizzled receptor function at these signaling centers in the mouse.

Clinical and pathological response to taxanes (T) and anthracycline (AC) based neoadjuvant chemotherapy (NAC) in locally advanced breast cancer (LABC): A retrospective analysis from a single institution in North India

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Background: In India LABC remains a common presentation of breast cancer (BC). Pathological complete response (pCR) achievement is crucial for increasing survival in LABC. Taxanes and anthracyclines are amongst agents with highest activity in BC. We retrospectively evaluated clinical and pathological responses in LABC patients (pts) treated with T and AC based chemotherapy. Methods: 32 LABC pts with clinical stage IIB, IIIA, IIIB, IIIC who had received T & AC based NAC between October 2002 and October 2006 were evaluated. Patients received doxorubicin 60mg/m2 (21 pts) or epirubicin 75 mg/m2 (11 pts) and docetaxel 75 mg/m2 (all pts) 3 weekly for 3–4 cycles followed by surgery. Most pts received same chemotherapy as adjuvant and also radiation therapy and hormonal treatment depending upon ER, PgR status. Results: Baseline characteristics of 32 pts: median age 50 years (range 26–65); all female; performance status 0–1; clinical stage IIB (3 pts), IIIA (9 pts), IIIB (16 pts), IIIC (4 pts); node positive (25 pts), hormone receptor positive (17 pts), unknown (1 pt); 29 pts received 3 cycles of NAC, 3 pts received 4 cycles of NAC. Growth factor was used in all patients. 31 pts underwent MRM; 5 pts had clinically complete response (16%), 22 pts had partial response (69%), 4 pts had stable disease (12%), 1 pt had progressive disease (3%); pathological complete response was seen in 4 pts (12 %). There were 2 events of febrile neutropenia; grade 3 or 4 neutropenia was seen in 26 pts (81%). There was no significant thrombocytopenia, cardiovascular event and hypersensitivity reaction. Conclusions: Our analysis indicates that T and AC based chemotherapy is well tolerated and effective in Indian pts with LABC with response rates similar to international studies.

No significant financial relationships to disclose.

Development of dopaminergic neurons in the mammalian brain

Dopaminergic neurons in the mammalian brain have received substantial attention in the past given their fundamental role in several body functions and behaviours. The largest dopaminergic population is found in two nuclei of the ventral midbrain. Cells of the substantia nigra pars compacta are involved in the control of voluntary movements and postural reflexes, and their degeneration in the adult brain leads to Parkinson's disease. Cells of the ventral tegmental area modulate rewarding and cognitive behaviours, and their dysfunction is involved in the pathogenesis of addictive disorders and schizophrenia. Because of their clinical relevance, the embryonic development and maintenance of the midbrain dopaminergic cell groups in the adult have been intensively studied in recent years. In the present review, we provide an overview of the mechanisms and factors involved in the development of dopaminergic neurons in the mammalian brain, with a special emphasis on the midbrain dopaminergic population.

Socioeconomic predictors of unconstrained child growth in Muscat, Oman

Weconducted a study to identify socioeconomic factors associated with unconstrained growth among preschoolers in Muscat, Oman. A sample of children born in 1995 and aged 28-43 months was drawn from the Child Health Registers of 2 health care centres. Sociodemographic data were collected by oral interview and maternal and child anthropometry measured. Regression analysis was used to identify socioeconomic indicators and cut-offs associated with unconstrained growth. Children from households with a monthly income > or = 800 Omani rials and mother’s education > or = 4 years attained height-for-age levels comparable to the current international growth reference. By screening using this criterion, we could obtain a suitable sample for the World Health Organization Multicentre Growth Reference Study in Muscat

Socioeconomic predictors of unconstrained child growth in Muscat, Oman

We conducted a study to identify socioeconomic factors associated with unconstrained growth among preschoolers in Muscat, Oman. A sample of children born in 1995 and aged 28-43 months was drawn from the Child Health Registers of 2 health care centres. Sociodemographic data were collected by oral interview and maternal and child anthropometry measured. Regression analysis was used to identify socioeconomic indicators and cut-offs associated with unconstrained growth. Children from households with a monthly income > or = 800 Omani rials and mother's education > or = 4 years attained height-for-age levels comparable to the current international growth reference. By screening using this criterion, we could obtain a suitable sample for the World Health Organization Multicentre Growth Reference Study in Muscat.

Identification of biochemical pathways for the metabolism of oxidized low-density lipoprotein derived aldehyde-4-hydroxy trans-2-nonenal in vascular smooth muscle cells

Oxidation of low-density lipoproteins (LDL) generates high concentrations of unsaturated aldehydes, such as 4-hydroxy trans-2-nonenal (HNE). These aldehydes are mitogenic to vascular smooth muscle cells and sustain a vascular inflammation. Nevertheless, the processes that mediate and regulate the vascular metabolism of these aldehydes have not been examined. In this communication, we report the identification of the major metabolic pathways and products of [(3)H]-HNE in rat aortic smooth muscle cells in culture. High-performance liquid chromatography separation of the radioactivity recovered from these cells revealed that a large (60-65%) proportion of the metabolism was linked to glutathione (GSH). Electrospray mass spectrometry showed that glutathionyl-1,4 dihydroxynonene (GS-DHN) was the major metabolite of HNE in these cells. The formation of GS-DHN appears to be due aldose reductase (AR)-catalyzed reduction of glutathionyl 4-hydroxynonanal (GS-HNE), since inhibitors of AR (tolrestat or sorbinil) prevented GS-DHN formation, and increased the fraction of the glutathione conjugate remaining as GS-HNE. Gas chromatography-chemical ionization mass spectroscopy of the metabolites identified a subsidiary route of HNE metabolism leading to the formation of 4-hydroxynonanoic acid (HNA). Oxidation to HNA accounted for 25-30% of HNE metabolism. The formation of HNA was inhibited by cyanamide, indicating that the acid is derived from an aldehyde dehydrogenase (ALDH)-catalyzed pathway. The overall rate of HNE metabolism was insensitive to inhibition of AR or ALDH, although inhibition of HNA formation by cyanamide led to a corresponding increase in the fraction of HNE metabolized by the GSH-linked pathway, indicating that ALDH-catalyzed oxidation competes with glutathione conjugation. These metabolic pathways may be the key regulators of the vascular effects of HNE and oxidized LDL.

Vasopressin mRNA localization in nerve cells: characterization of cis-acting elements and trans-acting factors

mRNA localization is a complex pathway. Besides mRNA sorting per se, this process includes aspects of regulated translation. It requires protein factors that interact with defined sequences (or sequence motifs) of the transcript, and the protein/RNA complexes are finally guided along the cytoskeleton to their ultimate destinations. The mRNA encoding the vasopressin (VP) precursor protein is localized to the nerve cell processes in vivo and in primary cultured nerve cells. Sorting of VP transcripts to dendrites is mediated by the last 395 nucleotides of the mRNA, the dendritic localizer sequence, and it depends on intact microtubules. In vitro interaction studies with cytosolic extracts demonstrated specific binding of a protein, enriched in nerve cell tissues, to the radiolabeled dendritic localizer sequence probe. Biochemical purification revealed that this protein is the multifunctional poly(A)-binding protein (PABP). It is well known for its ability to bind with high affinity to poly(A) tails of mRNAs, prerequisite for mRNA stabilization and stimulation of translational initiation, respectively. With lower affinities, PABP can also associate with non-poly(A) sequences. The physiological consequences of these PABP/RNA interactions are far from clear but may include functions such as translational silencing. Presumably, the translational state of mRNAs subject to dendritic sorting is influenced by external stimuli. PABP thus could be a component required to regulate local synthesis of the VP precursor and possibly of other proteins.

The effects of remifentanil on haemodynamic stability during rigid bronchoscopy

We examined the effect of remifentanil on the haemodynamic response to rigid bronchoscopy in 22 adult ASA 2-4 patients, randomly allocated to receive 1.0 microg.kg-1 remifentanil over 1 min followed by 0.5 microg.kg-1.min-1 (remifentanil group) or 2.0 microg.kg-1 fentanyl followed by a saline infusion (control group). Following the initial infusion, all patients received a sleep dose of propofol followed by rocuronium 0.6 mg.kg-1 and their lungs were ventilated using a Sander's injector attached to the rigid bronchoscope. Direct arterial blood pressures, heart rate and ST segment changes on the CM5 lead configuration of the electrocardiograph were measured at 1-min intervals from before induction of anaesthesia until the end of bronchoscopy. Arterial pressures and heart rate were similar in the two groups before and after induction of anaesthesia. Remifentanil attenuated the haemodynamic response to bronchoscopy (p < 0.05 for increases in arterial pressures and heart rate). Four patients in the remifentanil group had ST segment depression compared with eight patients in the control group, but this was not statistically significant.

Malformation of the functional organization of somatosensory cortex in adult ephrin-A5 knock-out mice revealed by in vivo functional imaging

The molecular mechanisms that coordinate the functional organization of the mammalian neocortex are largely unknown. We tested the involvement of a putative guidance label, ephrin-A5, in the functional organization of the somatosensory cortex by quantifying the functional representations of individual whiskers in vivo in adult ephrin-A5 knock-out mice, using intrinsic signal optical imaging. In wild-type mice ephrin-A5 is expressed in a gradient in the somatosensory cortex during development. In adult ephrin-A5 knock-out mice, we found a spatial gradient of change in the amount of cortical territory shared by individual whisker functional representations across the somatosensory cortex, as well as a gradient of change in the distance between the functional representations. Both gradients of change were in correspondence with the developmental expression gradient of ephrin-A5 in wild-type mice. These changes involved malformations of the cortical spacing of the thalamocortical components, without concurrent malformations of the intracortical components of individual whisker functional representations. Overall, these results suggest that a developmental guidance label, such as ephrin-A5, is involved in establishing certain spatial relationships of the functional organization of the adult neocortex, and they underscore the advantage of investigating gene manipulation using in vivo functional imaging.

Visualizing and quantifying evoked cortical activity assessed with intrinsic signal imaging

Intrinsic signal imaging (ISI) measures changes in light reflectance from the illuminated cortex (intrinsic signals or IS) attributed to various vascular and metabolic sources that, when using illumination in the 600 nm range, appear to co-localize with neuronal activity. Given the multiple sources contributing to the collected IS, the common practice of averaging across an extended post-stimulus time epoch before dividing by baseline data typically visualizes evoked IS overlying both the cortical tissue and the large surface blood vessels. In rat PMBSF, the contribution from these vessels are problematic as they do not co-localize with known PMBSF function. Determining a means for quantifying the evoked IS area poses an additional challenge. Here, we describe how exploiting IS collected shortly after stimulus onset (within 1.5 s), which coincides with fast oxygen consumption of active neurons, visualizes evoked IS overlying the cortical tissue without the large surface vessels. We also describe how the use of absolute thresholds combined with a baseline determined from data collected immediately prior to stimulus onset (within 1 s) targets most precisely a specific evoked IS amplitude, a method that should be especially useful when evoked areas are expected to occupy a substantial portion of the total imaged area and/or when peak activity is expected to differ between subjects.

A mapping label required for normal scale of body representation in the cortex

The neocortical primary somatosensory area (S1) consists of a map of the body surface. The cortical area devoted to different regions, such as parts of the face or hands, reflects their functional importance. Here we investigated the role of genetically determined positional labels in neocortical mapping. Ephrin-A5 was expressed in a medial > lateral gradient across S1, whereas its receptor EphA4 was in a matching gradient across the thalamic ventrobasal (VB) complex, which provides S1 input. Ephrin-A5 had topographically specific effects on VB axon guidance in vitro. Ephrin-A5 gene disruption caused graded, topographically specific distortion in the S1 body map, with medial regions contracted and lateral regions expanded, changing relative areas up to 50% in developing and adult mice. These results provide evidence for within-area thalamocortical mapping labels and show that a genetic difference can cause a lasting change in relative scale of different regions within a topographic map.

Identification of both general and region-specific embryonic CNS enhancer elements in the nestin promoter

In this report, we investigate how nestin expression is controlled in neural progenitor cells of the embryonic CNS. A 374-bp region in the second intron of the human nestin gene is sufficient, and a 120-bp sequence in this region is required, to express the lacZ reporter gene throughout the developing CNS of E9.5-10.5 transgenic mouse embryos. The 120-bp element region contains putative binding sites for nuclear hormone receptors and we show that TRs, RXR, RAR, and COUP-TF bind to these motifs. A separate enhancer, located most probably 5' to the 120-bp sequence in the second intron, controls midbrain expression at E10.5. In conclusion, our data show that the nestin enhancer in the second intron contains elements both for general and for region-specific CNS progenitor cell expression and suggest that nuclear hormone receptors play a role in the regulation of nestin expression in the early CNS.

Decreased vascular endothelial growth factor expression associated with tumor regression induced by (E)-2'-deoxy-2'-(fluoromethylene)cytidine (MDL 101,731)

The effect of the antitumor drug MDL 101,731 [(E)-2'-deoxy-2'-(fluoromethylene)cytidine] on tumor growth and on steady-state vascular endothelial growth factor (VEGF) mRNA levels in MDA-MB-231, PC-3, MCF-7, and HT-29 human tumor xenografts grown in nude mice was examined, using quantitative in situ hybridization. MDL 101,731 caused regression of MDA-MB-231 and PC-3 tumor xenografts, but only inhibition of growth (without regression) of MCF-7 xenografts. The drug caused inhibition of growth of HT-29 xenografts at low doses, and regression at high doses. When treatment with MDL 101,731 led to tumor regression, VEGF mRNA levels were decreased. When treatment led only to inhibition of growth, there was no significant change in VEGF mRNA. Further examination of the tumor xenografts revealed that elevated VEGF mRNA was associated with hypoxic zones surrounding areas of necrosis in the tumors, and that the drop in VEGF mRNA observed in tumors from mice treated with MDL 101,731 correlated with a loss of zones of necrosis. In contrast, treatment with cisplatin led to either an increase (PC-3) or no change (MDA-MB-231) in VEGF mRNA levels, and no loss of necrotic zones. Quantitative analysis of changes in VEGF mRNA levels was supported by immunohistochemical analysis of VEGF protein in the same tumor specimens. In vitro, MDL 101,731 was a potent inhibitor of VEGF secretion in cells exposed to hypoxia, whereas there was no effect of cisplatin on VEGF secretion by three of the four cell lines tested. These findings suggest that inhibition of VEGF expression by MDL 101,731 may distinguish this compound from other classes of cytotoxic agents, such as cisplatin.

Dendritic localization of rat vasopressin mRNA: ultrastructural analysis and mapping of targeting elements

Transcripts encoding the vasopressin precursor are located in axons and dendrites of rat hypothalamic magnocellular neurons. While the axonal vasopressin mRNA has been extensively characterized both at the biochemical and morphological level, little is known about those transcripts residing in dendrites of magnocellular neurons. As revealed by in situ hybridization at the electron microscopic level, the mRNA is located in proximal and distal dendritic segments and is exclusively confined to regions containing rough endoplasmic reticulum. These results suggest that dendrites of hypothalamic neurons may be capable of local precursor synthesis independent of that occurring in the cell somata. A heterologous system has been employed to define cis-acting elements within the vasopressin mRNA which may be involved in dendritic compartmentalization. Expression vector constructs consisting of the cytomegalovirus promoter coupled to the rat vasopressin cDNA have been injected into the cell nuclei of cultured neurons derived from embryonic rat superior cervical ganglia. Vector-encoded vasopressin transcripts were also sorted to dendrites of these neurons indicating that the molecular determinants of dendritic mRNA transport are not cell specific. Mapping of the targeting elements revealed two segments within the vasopressin mRNA that are able to confer dendritic compartmentalization to alpha-tubulin mRNA which is normally confined to the cell body.

RAPID and opposite effects of BDNF and NGF on the functional organization of the adult cortex in vivo

The adult cortex is thought to undergo plastic changes that are closely dependent on neuronal activity (reviewed in ref. 1), although it is not yet known what molecules are involved. Neurotrophins and their receptors have been implicated in several aspects of developmental plasticity, and their expression in the adult cortex suggests additional roles in adult plasticity. To examine these potential roles in vivo, we used intrinsic-signal optical imaging to quantify the effects of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) on the functional representation of a stimulated whisker in the 'barrel' subdivision of the rat somatosensory cortex. Topical application of BDNF resulted in a rapid and long-lasting decrease in the size of a whisker representation, and a decrease in the amplitude of the activity-dependent intrinsic signal. In contrast, NGF application resulted in a rapid but transient increase in the size of a representation, and an increase in the amplitude of the activity-dependent intrinsic signal. These results demonstrate that neurotrophins can rapidly modulate stimulus-dependent activity in adult cortex, and suggest a role for neurotrophins in regulating adult cortical plasticity.