Top PDF First early hominin from central Africa (Ishango, Democratic Republic of Congo).

First early hominin from central Africa (Ishango, Democratic Republic of Congo).

First early hominin from central Africa (Ishango, Democratic Republic of Congo).

We are grateful to the following institutions and persons that gave permission to study the comparative material. In the following cases, the institution was the legal repository for the fossil material: Arche´ologie andennaise, Belgium (D. Bonjean), Senckenberg Research Institute (F. Schrenk and O. Kullmer), Croatian Museum of Natural History (J. Radovcˇic´), Ditsong National Museum of Natural History (S. Potze), Institut de Pale´ontologie Humaine (H. de Lumley, D. Grimaud-Herve´), Institutul de Antropologie ‘‘Francisc I. Rainer’’ (A. D. Soficaru), Max Planck Institute for Evolutionary Anthropology (J.-J. Hublin), Museo Nacional de Ciencias Naturales (A. Rosas), Muse´e d’Angouleˆme (J.-F. Tournepiche), Muse´e d’Arche´ologie Nationale, National Museums of Kenya (E. Mbua), Muse´e National de Pre´histoire (J.-J. Cleyet-Merle), Rockefeller Museum, Sackler School of Medicine (Y. Rak, A. Barash, I. Hershkovitz), University of Witwatersrand (B. Zipfel), Staatliches Museum fu¨r Naturkunde (R. Ziegler), Rheinisches Landesmuseum (H. Joachim), Russian Academy of Science Archaeology Institute (T. Balueva), National Museum of Archaeology in Lisbon, Iziko South African Museum. In the case of the British Museum (N. Spencer, D. Antoine), the Department of Anthropology in the Colorado University in Boulder (D. Van Gerven), and the Royal Belgian Institute of Natural Sciences, the specimen(s) was/were donated to the institution. The specimens from the Department of Anthropology of the National Museum of Natural History (Smithsonian Institution, D. Hunt) are on loan. S. Prat and H. Roche gave access to the specimen in their care. Finally, the comparative material from the Museum fu¨r Vor- und Fru¨hgeschichte, Staatliche Museum zu Berlin (A. Hoffmann & W. Menghin) was purchased by this institution.
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Conquest, occupation, colonialism and exclusion: land disputes in Angola

Conquest, occupation, colonialism and exclusion: land disputes in Angola

Colonial officers removed from power rulers who resisted or challenged Portuguese wars of conquest in the seventeenth, eighteenth and early nineteenth centuries. Those local authorities were later replaced by more collaborative rulers. Two centuries of signed vassalage treaties provoked major political rearrangements in West Central Africa. Until the mid-nineteenth century, Portuguese colonialism in Angola was based on the control over subjects, not of continuous territorial occupation (Miller 1976; Dias 1986; Santos 2007; Candido 2013a: 70-76). After that, the colonial state shifted to the belief that territorial control was vital to imperial aspirations. Local men and women adjusted to the new realities, in the same way that their ancestors had done in earlier times. By the mid-nineteenth century, Portuguese colonialism had disrupted local notions of land use and ownership, imposing new models and new ways to claim property.
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Plio-Pleistocene aardvarks (Mammalia, Tubulidentata) from East Africa

Plio-Pleistocene aardvarks (Mammalia, Tubulidentata) from East Africa

Since the early Miocene, 14 species of Tubulidentata have been described from Africa and Eurasia (see Leh- man 2006). During the Plio-Pleistocene, only three spe- cies from a single genus are known in Africa, but their distribution was considered to be restricted. Only the extant O. afer was known to show a continental distri- bution but the first stages of its expansion are equivo- cal. The revision of the Kenyan specimens and the de- scription of new material from Ethiopia and Kenya demonstrate, for the first time, that a fossil species was present at the same time in two distant regions of Afri- ca: Chad on the one hand, and Ethiopia and Kenya on the other hand. O. djourabensis would thus be the old- est-known species of aardvark to have achieved a con- tinental dispersal. The two regions where this species has been discovered are situated east and west of the Rift Valley. According to this analysis, the distribution of fossil Tubulidentata was not influenced by the Rift during Plio-Pleistocene times. As recognised for other mammals (see Brunet et al. 1998), passage between Central and East Africa was possible. It would seem, therefore, plausible that early hominids could also have crossed the Rift Valley during the Plio-Pleistocene and
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Adherence to drug-refill is a useful early warning indicator of virologic and immunologic failure among HIV patients on first-line ART in South Africa.

Adherence to drug-refill is a useful early warning indicator of virologic and immunologic failure among HIV patients on first-line ART in South Africa.

Earlier reports from resource-limited settings have defined virologic failure as a VL of .400, .1,000 or .5,000 copies/ml at one or two repeated visits [14,15]. However, drug resistance mutations can emerge at lower VL levels [16] and in high-income countries, monitoring guidelines recommend using VL .50 copies/ ml as an indicator of virologic failure for patients on ART [17]. As more robust, sensitive and lower cost assays are developed, ART programmes in low- and middle-income may be able to adopt lower threshold values for virologic failure. Thus, we assessed the proportion of repeated VL .50 copies/ml, immunologic failure and median CD4 cell count gains in a cohort of long-term, first-line recipients in Soweto, who had been on NNTRI-based regimens for up to eight years. We also assessed the relationship between cumulative adherence to drug-refill visits and treatment failure.
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Hominin responses to environmental changes during the Middle Pleistocene in Central and Southern Italy

Hominin responses to environmental changes during the Middle Pleistocene in Central and Southern Italy

The faunal records of the studied period partially cover two successive MA, from the middle Galerian (Isernia FU) to the early Aurelian (Torre in Pietra FU). Therefore, human communities had to adapt their activities to the evolution of the ecosystems, especially during these faunal turnovers. Subsistence behavior analysis from the ear- liest sites (La Pineta and Notarchirico) highlighted that the local populations mainly

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The First Modern Human Dispersals across Africa

The First Modern Human Dispersals across Africa

The emergence of more refined chronologies for climate change and archaeology in prehistoric Africa, and for the evolution of human mitochondrial DNA (mtDNA), now make it feasible to test more sophisticated models of early modern human dispersals suggested by mtDNA distributions. Here we have generated 42 novel whole-mtDNA genomes belonging to haplogroup L0, the most divergent clade in the maternal line of descent, and analysed them alongside the growing database of African lineages belonging to L0’s sister clade, L1’6. We propose that the last common ancestor of modern human mtDNAs (carried by “mitochondrial Eve”) possibly arose in central Africa ~180 ka, at a time of low population size. By ~130 ka two distinct groups of anatomically modern humans co-existed in Africa: broadly, the ancestors of many modern-day Khoe and San populations in the south and a second central/ eastern African group that includes the ancestors of most extant worldwide populations. Early modern human dispersals correlate with climate changes, particularly the tropical African “megadroughts” of MIS 5 (marine isotope stage 5, 135–75 ka) which paradoxically may have facilitated expansions in central and eastern Africa, ultimately triggering the dispersal out of Africa of people carrying haplogroup L3 ~60 ka. Two south to east migrations are discernible within haplogroup LO. One, between 120 and 75 ka, represents the first unambiguous long-range modern human dispersal detected by mtDNA and might have allowed the dispersal of several markers of modernity. A second one, within the last 20 ka signalled by L0d, may have been responsible for the spread of southern click- consonant languages to eastern Africa, contrary to the view that these eastern examples constitute relicts of an ancient, much wider distribution.
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Palavras-chave: Macrostemum alienum, larva, Trichoptera Hydropsychidae, Macronematinae, Nigeria, West Africa

Palavras-chave: Macrostemum alienum, larva, Trichoptera Hydropsychidae, Macronematinae, Nigeria, West Africa

Earlier reports on hydropsychid caddisflies in the Afrotropical region were mainly from East, Central and South- ern Africa (Scott 1988, Anderson & Johanson 1992) with a few from West Africa (Petr 1970, Gibbs 1973, Hynes 1975). However, there have been a number of recent reports from West Africa (Marlier 1978, Statzner 1984, Statzner & Gibon 1984, Statzner et al. 1985, 1987 Gibon et al. 1994, Kjaerandsen & Andersen1997, Andersen & Kjaerandsen 2001), but they are from just a few countries in the sub-region. Therefore, as pointed out in Andersen & Kjaerandsen (2001) and Kjaerandsen (2005), it is evident that the hydropsychid caddisfly fauna of the rest of the West-African sub-region is not completely known. Furthermore, many described spe- cies also need redescription to allow for clear, precise rec- ognition (Kjaerandsen 2005). For example, there is a dearth of information pertaining to the caddisfly fauna in Nigeria compared to those in other West African countries, such as Ghana (Gibbs 1973, Kjaerandsen & Andersen 1997) and Ivory Coast (Statzner 1982, 1984), where extensive studies have been carried out. The first documented study of hydropsychid caddisflies in Nigeria is in the author’s earlier paper (Ogbogu 2001) in which larvae were observed in a reservoir spillway.
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The first hominin from the early Pleistocene paleocave of Haasgat, South Africa

The first hominin from the early Pleistocene paleocave of Haasgat, South Africa

The Haasgat fossil site is a paleokarstic deposit consisting of a large cave passage completely in-filled with calcified cave sediments and interstratified speleothem, the latter of which was largely removed by lime mining at the turn of the 20th century. This mining activity also generated a large talus slope outside the cave consisting of fossil bearing paleocaves sediment blocks that have yielded the Haasgat ex situ faunal assemblage (HGD; Keyser, 1991; Keyser & Martini, 1991; McKee & Keyser, 1994; Plug & Keyser, 1994; Adams, 2012). The Haasgat primate community is unique relative to that reported from most Bloubank Valley sites (e.g., Sterkfontein, Swartkrans, Cooper’s, Kromdraai), with the most demographically diverse and potentially oldest sample of the basal Papio species, Papio angusticeps, in the African fossil record (Freedman, 1957; Gilbert et al., 2015). Haasgat is also the only site currently documenting multiple fossil colobine species (Cercopithecoides haasgati, Cercopithecoides williamsi, Cercopithecoides sp.) in South Africa (McKee & Keyser, 1994; McKee, Von Mayer & Kuykendall, 2011; Kegley, Hemingway & Adams, 2011; Adams, 2012; Adams et al., 2015). The overall mammalian faunal assemblage is also unusual in the low representation of Order Carnivora, as well as the recovery of primitive alcelaphins/ovibovins and a high proportion of extremely large klipspringers (Oreotragus sp.) that are more similar to those from the Makapansgat Member 3 deposits (3.03–2.58 Ma; Herries et al, 2013) than those recovered from the nearby Gondolin GD 2 deposits (∼1.8 Ma; Herries et al., 2006; Adams, 2010; Adams, 2012). Despite this rich and regionally-unique faunal community established through the ex situ HGD assemblage, no hominins were recovered during the first phases of paleontological sampling at Haasgat. This paper provides a comprehensive morphological and dental microstructure analysis of the first hominin specimen, a partial maxillary molar (HGT 500; Fig. 2), that was recovered from a calcified ex situ dumpsite block collected in 2011 from the site.
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Rev. Bras. Psiquiatr.  vol.37 número4

Rev. Bras. Psiquiatr. vol.37 número4

Methods: A selective literature search of the PubMed, Embase, PsycINFO, and ISI databases from inception until March 2014 was performed. Included in this review were articles that a) characterized prodromal and first-episode stages of BD or b) detailed efficacy and safety/tolerability of interventions in patients considered prodromal for BD or those with only one episode of mania/hypomania. Results: As research has only recently focused on characterization of the early phase of BD, there is little evidence for the effectiveness of any treatment option in the early phase of BD. Case management; individual, group, and family therapy; supportive therapy; and group psychoeducation programs have been proposed. Most evidence-based treatment guidelines for BD do not address treatment specifically in the context of the early stages of illness. Evidence for pharmacotherapy is usually presented in relation to illness polarity (i.e., manic/mixed or depressed) or treatment phase. Conclusions: Although early recognition and treatment are critical to preventing unfavorable outcomes, there is currently little evidence for interventions in these stages of BD.
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In vitro regeneration and antibacterial activity of Prunus domestica L.

In vitro regeneration and antibacterial activity of Prunus domestica L.

transferred to the rooting medium (Tian et al., 2007). According to Padilla et al. (2003) and Tian et al. (2007) addition of higher concentrations of NAA in the medium has been reported to increase rooting. In present study, roots were greatly increased by adding NAA in the ½ MS medium. Highest root number. was appeared 7.0 at 1.0 mg/l IBA. But Petri & Scorza (2009) showed that highest root number appeared 2.3. 37 days were needed from initial culture to the establishment of rooted plants in the outside environment. Mante et al. (1989) established a method of plant regeneration for a time period about 100 days.
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Cad. Saúde Pública  vol.24 suppl.2

Cad. Saúde Pública vol.24 suppl.2

This study evaluates the association between postpartum depression and interruption of ex- clusive breastfeeding in the first two months of life. Cohort study of 429 infants ≤ 20 days of age to four primary health care units in Rio de Janeiro, Brazil. Interruption of exclusive breast- feeding (outcome) was defined as the introduc- tion of water, other types of liquids, milk, or for- mulas or any food. Postpartum depression was assessed using the Edinburgh Post-Natal De- pression Scale. Associations between variables were expressed as prevalence ratios (baseline) and risk ratios (follow-up), with their respec- tive 95% confidence intervals, estimated by Pois- son regression with robust variance. Children of mothers with postpartum depressive symptoms were at higher risk of early interruption of exclu- sive breastfeeding in the first and second months of follow-up (RR = 1.46; 95%CI: 0.98-2.17 and RR = 1.21; 95%CI: 1.02-1.45, respectively). Con- sidering mothers that were exclusively breast- feeding at the first month, postpartum depres- sion was not associated with interruption of ex- clusive breastfeeding in the second month (RR = 1.44; 95%CI: 0.68-3.06). The results indicate the importance of maternal mental health for the success of exclusive breastfeeding.
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How small accounting firms can compete in an environment in which the big four are getting bigger

How small accounting firms can compete in an environment in which the big four are getting bigger

This paper sets out to determine how small accounting firms can compete in the United States in the early 21 st century. The first chapter identifies the central goal of the paper: namely, to use existing literature and market data to define a business strategy for Ross & Moncure, Inc., a small accounting firm in the metropolitan Washington area. The second chapter is a literature review, and in it the author finds that large accounting firms are advantaged in terms of reputation, ability to diversify, and ability to retain employees, but are disadvantaged in their ability to form longstanding successful relationships with clients. In the third chapter, the author explores the relationship between the Big Four firms and their employees. The goal of this chapter is to determine how small accounting firms can compete for top talent in the HR market, and the author finds that this can be done by offering faster career progression and more client interaction. The fourth chapter looks at the market for accounting services in the United States, exploring the different options that consumers have to meet their accounting needs. It is found in this chapter that big and small accounting firms tend to compete for clients of different profiles. In the fifth chapter, the author uses proprietary company data to explore the composition, existing strategy and culture of Ross & Moncure. In the sixth chapter, all of the previous chapters come together to formulate a strategy and plan for action for Ross & Moncure: specifically, that the firm should further cultivate networks and relationships, and should create a fulfilling professional environment by increasing client-employee interaction, encouraging external education, and allowing employees to take on many different projects.
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An insight into the dilemma of african modernity and a theoretical response

An insight into the dilemma of african modernity and a theoretical response

The implication of this theory is that shared identity and good-will are the basic principles which African morality tends to defend. Arising from this, one can hold that core African values such as co-operation, consensus, reconciliation, commonality and related values sought by the African all serve to defend the principle of good will and shared identity. One can further hold that since morality spans nearly all of social life and forms the background of which all other social, political, economic achievements are weighed and measured it is safe to hold that this moral principle provides the background to understanding and interpreting all that should be considered good or bad within the mental universe of the African world. Thus, it is expected that other values as variously held by Africans: “sense of human value”, (O. Onwubiko, 1991, G. Onah cited in Metz, 2007); “sense of hospitality”, “sense of the sacred”, and “the sacredness of life”, “sense of community” “sense of good human relations”, “sense of identity” (O.Onwubiko,1991) are all geared towards defending these principles. Thus, the relevant position to note in relation to our discussion is the fact that African worldview to the extent that it is known to human memory had haboured the thesis that the other is a relevant component of being human and that man is at the centre of the moral and intellectual African world. In a classical statement in this regard John Mbiti (1969) had held that for the African “I is in the we and we is the I”. The negritude theorists were later to interpret this creed to mean “I dance the other I feel the other”, as. This position is reflected in a cluster of works on African history, thought and culture (Oliver Onwubiko, 19991; John Mbiti; 1970).
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The foreign debt problem of Africa

The foreign debt problem of Africa

A clear example of the special currency situation in Africa is the CFA franc zone with special ties to the French Treasury ( 19 ) . It encloses the Comores, the West African Monetary Union (UMOA) and the zone of the Bank of Central African States (BEAC). UMOA has seven members : Benin, Ivory Coast, Mali, Niger, Senegal, Togo and Burkina. BEAC has five members : Cameroon, Central African Republic, Congo, Chad and Gabon. For those countries the problems associated with the servicing of public and publicly guaranteed debt show some special features. On the one hand, the foreign exchange to service external debt is drawn from a common pool and therefore not constrained by an individual member's export earnings, and moreover, facilitated by net drawings from the French Treasury (Operations Account). On the other hand, to service its own debt, the government has to generate sufficient revenues in the common currency and can rely on money creation only within narrow limits. Thus, a crucial debt service variable is government revenues instead of export income.
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The Middle and Lower Xingu: the response to the crystallization of different temporalities in the production of regional space | Médio e Baixo Xingu: o reflexo da cristalização de diferentes temporalidades na produção do espaço regional

The Middle and Lower Xingu: the response to the crystallization of different temporalities in the production of regional space | Médio e Baixo Xingu: o reflexo da cristalização de diferentes temporalidades na produção do espaço regional

fragility of the affected populations (riparian, indigenous, small farmers, urban population, etc.), when faced with the overwhelming position of the state and companies in the Brazilian energy sector. While hydroelectric power is repeatedly presented as a clean, renewable, cheap source of energy, necessary for national development, high social costs are: reduced capacity of fishing and agriculture, relocation of the local population, cultural and material violence, problems of security and welfare are camouflaged amid expressive (inter) national ignorance regarding the region. According to Pinho and Costa (2012), while there is a proven relationship between sexual violence and the Belo Monte HPP, and an increase in the vulnerability of migrant families and their families, there is no evidence of a link between the increased migration of men and the rise of sexual violence. Representatives from the Specialized Reference Center for Social Assistance (CREAS) in Altamira consider that the construction of the Belo Monte HPP has considerably influenced an increase in demand for the center and with regard to this they state that:
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USE OF AFLPS TO DISTINGUISH LANDRACES OF PEJIBAYE (Bactris gasipaes) IN BRAZILIAN AMAZONIA

USE OF AFLPS TO DISTINGUISH LANDRACES OF PEJIBAYE (Bactris gasipaes) IN BRAZILIAN AMAZONIA

ABSTRACT: Although the first inhabitants of western Amazonia domesticated pejibaye (Bactris gasipaes Kunth, Palmae) or peach palm for its fruits, today it is widely planted for its heart-of-palm. Like other domesticates, pejibaye presents a complex hierarchy of landraces developed before the conquest of the Americas. The existence of three landraces (Pará, Solimões, Putumayo) was proposed along the Amazonas and Solimões Rivers, Brazil, based on morphological characteristics. There are some questions remaining about the intermediate landrace being an artifact of the morphometric analysis. AFLPs were used to evaluate the relationships among samples of these putative landraces. DNA was extracted from 99 plants representing 13 populations maintained in the Pejibaye Germplasm Bank, Manaus, AM; six primer combinations generated 245 markers via PCR, which were scored in an ABI Prism 310 sequencer and analyzed with GeneScan Software; Jaccard similarities were estimated and a dendrogram was generated with UPGMA. Two groups of plants were observed in the dendrogram instead of three, and were similar at 0.795. Each group contained two subgroups, similar at 0.815. One group (n=41) contained 73% Pará landrace plants, with one subgroup (n=22) containing 91% Pará, and the other (n=19) containing 53% Pará. The other group (n=58) contained 53% Solimões and 40% Putumayo landrace plants, with one subgroup (n=21) containing 52% Solimões and 43% Putumayo, and the other (n=35) containing 57% Solimões and 37% Putumayo. The first group confirmed the Pará landrace. The second group suggested that the Solimões landrace does not exist, but that the Putumayo landrace extends along the Solimões River to Central Amazonia.
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Growth of HIV-Exposed Uninfected Infants in the First 6 Months of Life in South Africa: The IeDEA-SA Collaboration.

Growth of HIV-Exposed Uninfected Infants in the First 6 Months of Life in South Africa: The IeDEA-SA Collaboration.

This was a retrospective cohort study based on routine data provided to the International Epide- miologic Databases to Evaluate AIDS, Southern Africa (IeDEA-SA, www.iedea-sa.org) collabora- tion. The IeDEA-SA cohort has been previously described [18,19], although this is the first analysis of HEU infants. Two South African sites were included in this analysis namely McCord Hospital (MH) in KwaZulu-Natal Province and Rahima Moosa Mother and Child Hospital (RMMCH), Gauteng Province. MH was a public-not-for-profit programme where a small patient co-payment was required at each visit, while RMMCH is a public hospital where care is provided at no cost to pregnant women and children 6 years old. Both facilities provided primary and secondary care. We included infants born from 2007–2013. Growth monitoring and promotion was provided based on standard practices at each facility. In South Africa, 2008 guidelines on infant feeding advocated HIV-infected mothers exclusively breastfeed their infants unless replacement feeding met the AFASS criteria, in which case free infant formula was provided for 6 months [20,21]. The 2010 PMTCT guidelines recommended the following antiretroviral regi- mens: women were eligible for lifelong ART (tenofovir (TDF) + lamivudine/emtricitabine (FTC) + nevirapine (NVP)) if they had a CD4 350 cells/μl or WHO clinical stage 3/4. Women not eli- gible for ART (CD4 >350 cells/μl or WHO clinical stage 1/2) received zidovudine (ZDV) from 14 week gestation followed by single dose NVP and ZDV during labour and TDF + FTC after delivery [22]. Prior to 2010, women at RMMCH received single dose nevirapine (sdNVP) at delivery only, while at MH ZDV from 14 weeks gestation plus sdNVP at delivery was used in women ineligible for triple ART (CD4 200 cells/μl). In 2011, the Tshwane declaration of sup- port for breastfeeding was signed, ending the provision of infant formula for PMTCT in state facilities, like RMMCH [23]. MH continued the provision of infant formulae.
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Model study of the cross-tropopause transport of biomass burning pollution

Model study of the cross-tropopause transport of biomass burning pollution

CO remains high during boreal winter, but not during austral winter. Figure 15 is the same as Fig. 14, except for the tropical LS (above 380 K and >60 mb; 12 ◦ N–12 ◦ S). Not surprisingly, the mean concentrations (16–25 ppbv) are lower than in the TTL and they peak 1–2 months later because of the transit time via slow ascent. The peak in total CO from SH burning in austral spring, as evident in the TTL (Fig. 14), is muted in the

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SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF DICHOTOMIN A ANALOGS

SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF DICHOTOMIN A ANALOGS

A cyclic hexapeptide dichotomin-A, Cyclo-L-[Gly-Thr-Phe-Leu-Tyr-Val] isolated from the roots of Stellaria dichotoma, showed cell growth inhibitory activity 1 and used as folk medicine for antifebrile. Several peptide antibiotics such as geodiamolides, arylomycin, clavariosporin were found to contain N-methylated amino acids in their ring structures 2-4 . A review of the structures of cyclic peptides exhibiting antimicrobial activity showed presence of D- amino acid and / or N- methylated amino acid units in the molecule. Hence two cyclic hexapeptides N-methylated analogs of dichotomin-A have been designed. Both the cyclic hexapeptides comprise of N, O- dimethylated Tyr units but the second one in addition to that contains one D-Val instead of L-Val. The two molecule (1) Cyclo-L-[Gly-Thr-Phe-Leu-(N-CH 3 ,O-CH 3 ) Tyr-Val] (2) Cyclo-L-[Gly-Thr-
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ULTRASOUND-MEDIATED SYNTHESIS PYRAZINE-2-CARBOXYLAMINO ACIDS AND DIPEPTIDES AS POTENT INSECTICIDAL AND

ULTRASOUND-MEDIATED SYNTHESIS PYRAZINE-2-CARBOXYLAMINO ACIDS AND DIPEPTIDES AS POTENT INSECTICIDAL AND

All the reactions requiring anhydrous conditions were conducted in flame dried apparatus. The amino acids used are L-amino acid, except D-alanine, purchased from Spectrochem Private Limited, Mumbai, India. Solvents and reagents were purified by standard methods. Boc-amino acids, amino acid methyl ester hydrochlorides and nitro-arginine were prepared by standard procedures. N-methylvaline was prepared using NaH/CH 3 I by Benoiton method 11 . Organic extracts were dried over anhydrous sodium sulphate. Melting

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