A new practical and economical technique for the obtention of high quality thin section photographs with the help of a simple optical microscope

Microscopic study is an indispensable step in the determination of the petrographic characteristics of rocks. In Cameroon just like in most developing countries, simple polarizing microscopes of the 20th Century constitute the only available material for macroscopic studies. A major difficulty encountered in the use of these instruments resides in the realisation of photographs of the different parts of the thin section that require illustrations. The technique that has been used upto now has been inefficient and unsatisfactory. Faced with this recurrent situation, we thought of setting up a new, semi-modern, practical and very economical technique for photographing the thin section.conferenc

Neoproterozoic metamorphic events in the kekem area (central domain of the Cameroon north equatorial fold belt): P-T data

The Kekem area (southwestern part of the central domain of the Cameroon North Equatorial Fold Belt) is composed of high-grade migmatitic gneisses in which two lithological units are distinguished: (i) a metasedimentary unit (garnet- sillimanite-biotite-gneisses and garnet-biotite-gneisses) interpreted as a continental series; and (ii) meta-igneous rocks comprising mafic pyroxene gneisses, amphibolites, and orthogneisses. These units recrystallised under HT-MP conditions (T=700-800‹C, P . 0.5-0.8GPa) and were deformed in relation to a major tangential tectonic event with the NNE-SSW kinematic direction. The lithological association and its tectono-metamorphic evolution show striking similarities with the Banyo and Maham III gneisses, suggesting that the extensional depositional environment envisaged for this formation can be extended farther west. P-T calculations in this contribution provide new data on the Pan-African structural and metamorphic evolution of the metapelites and metabasites in the basement of the Kekem area. The results show two distinct events: (1) crystallization during a Pan-African high temperature metamorphic event and, (2) subsequent deformation and high temperature mylonitization. The data imply a high-temperature amphibolite-facies metamorphism along a clockwise P-T path. The recorded P-T involves a marked variation in pressure, which is typical of collisional crustal thickening. The contrasted metamorphic evolution between areas located to the south of the Central Cameroon Shear Zone(CCSZ; high pressure: Yaounde, Ntui-Betamba), and those located to the north (low pressure: Banyo, Tibati), along with widespread remains of Paleoproterozoic crust, suggest important crustal thickening during Pan-African tangential tectonics in southern Cameroon. As a consequence, the CCSZ is not simply a late Pan-African transpressive shear zone but appears to have been formerly a major intracontinental thrust zone.Key words: HT metamorphic event / Kekem/ Cameroon / Collisional crustal thickening / Neoproterozoic /North Equatorial Fold Belt.La region de Kekem est formee de gneiss anatectiques de haut-degre dans lesquels deux ensembles sont reconnus: (i) un ensemble metasedimentaire (gneiss a grenat, sillimanite et biotite, et gneiss a grenat et biotite) considere comme depose a lLinterieur dLun continent, (ii) des roches meta-ignees comprenant des gneiss a grenat et pyroxene,des amphibolites de composition mafique, et des orthogneiss. Ces deux ensembles ont recristallise (T=700-800‹C, P. 0,5-0,8GPa) et ont ete deformes en relation avec un episode majeur de tectonique tangentielle de direction cinematique NNE-SSW. Cette association lithologique et son evolution tectono-metamorphique montrent une similitude remarquable avec les formations panafricaines de Banyo et Maham III du domaine central de la chaine, suggerant que le contexte extensif de depot envisage pour ces dernieres peut etre etendu plus a lLouest. Les donnees nouvelles sur lLevolution tectono-metamorphique des metasediments et des metabasites panafricains du socle de la region de Kekem mettent en evidence un metamorphisme panafricain de haute temperature suivi dLune mylonitisation a haute temperature dans le facies amphibolite de haut degre selon un chemin P-T horaire. Les conditions P-T enregistrees se caracterisent par une variation de pression typique dLun epaississement crustal. LLevolution metamorphique panafricaine contrastee entre le domaine au sud du cisaillement Centre Camerounais(CCC; haute pression: Yaounde, Ntui-Betamba) et le domaine nord-CCC (basse a moyenne pression: Banyo, Tibati) ainsi que la presence ubiquiste de reliques dLune croute ancienne paleoproterozoique, suggerent un important epaississement crustal, lors dLun episode de tectonique tangentielle. Le CCC nLest donc pas un simple accident panafricain transpressif, mais apparait bien avoir ete prealablement un  chevauchement intracontinental majeur.Mots-cles : Metamorphisme de Haut degre/Kekem/ Cameroun/ Epaississement crustal/ Neoproterozoique /Chaine Nord Equatoria

The Macrocyclic Peptide Natural Product CJ-15,208 Is Orally Active and Prevents Reinstatement of Extinguished Cocaine-Seeking Behavior

The macrocyclic tetrapeptide natural product CJ-15,208 (cyclo[Phe-d-Pro-Phe-Trp]) exhibited both dose-dependent antinociception and kappa opioid receptor (KOR) antagonist activity after oral administration. CJ-15,208 antagonized a centrally administered KOR selective agonist, providing strong evidence it crosses the blood–brain barrier to reach KOR in the CNS. Orally administered CJ-15,208 also prevented both cocaine- and stress-induced reinstatement of extinguished cocaine-seeking behavior in the conditioned place preference assay in a time- and dose-dependent manner. Thus, CJ-15,208 is a promising lead compound with a unique activity profile for potential development, particularly as a therapeutic to prevent relapse to drug-seeking behavior in abstinent subjects

Dynamic interaction in tropical Africa: IGCP-616Y and IGCP 646 projects and events

The scientific objectives and research program of the IGCP-646 project (2015–2018) cuts across many disciplines and includes various aspects of continental basement geology, resource exploration (mineral, water and hydrocarbons), geohazard mitigation, and climate change, all of which are of critical importance to developing countries, particularly in parts of West Africa where population pressures are on the rise. Considerable emphasis was placed on capacity building, creation of opportunities for young scientists to undertake higher degrees programs, knowledge transfer and training. The SIDA-funded “pilot project” IGCP-616Y (started in 2012), focused on three objects (i) crustal architecture, tectonic evolution and regional geology of Central Africa and the connection with NE Brazil; (ii) the Mesozoic continental rifting and breakup leading to a better integration of the onshore and offshore geology; (iii) clarification and quantification of the links between basement structures, neotectonics, climate change and landscape evolution. The IGCP-616Y and IGCP-646 projects consisted of over 250 researchers, from different countries. In the course of the projects, six annual meetings, four field trips/workshops, as well as several training sessions were organized. Here we provide a summary of the scientific targets of the projects and a summary of the organized activities

Phenylalanine Stereoisomers of CJ-15,208 and [d-Trp]CJ-15,208 Exhibit Distinctly Different Opioid Activity Profiles

This work is licensed under a Creative Commons Attribution 4.0 International License.The macrocyclic tetrapeptide cyclo[Phe-d-Pro-Phe-Trp] (CJ-15,208) and its stereoisomer cyclo[Phe-d-Pro-Phe-d-Trp] exhibit different opioid activity profiles in vivo. The present study evaluated the influence of the Phe residues’ stereochemistry on the peptides’ opioid activity. Five stereoisomers were synthesized by a combination of solid-phase peptide synthesis and cyclization in solution. The analogs were evaluated in vitro for opioid receptor affinity in radioligand competition binding assays, and for opioid activity and selectivity in vivo in the mouse 55 °C warm-water tail-withdrawal assay. Potential liabilities of locomotor impairment, respiratory depression, acute tolerance development, and place conditioning were also assessed in vivo. All of the stereoisomers exhibited antinociception following either intracerebroventricular or oral administration differentially mediated by multiple opioid receptors, with kappa opioid receptor (KOR) activity contributing for all of the peptides. However, unlike the parent peptides, KOR antagonism was exhibited by only one stereoisomer, while another isomer produced DOR antagonism. The stereoisomers of CJ-15,208 lacked significant respiratory effects, while the [d-Trp]CJ-15,208 stereoisomers did not elicit antinociceptive tolerance. Two isomers, cyclo[d-Phe-d-Pro-d-Phe-Trp] (3) and cyclo[Phe-d-Pro-d-Phe-d-Trp] (5), did not elicit either preference or aversion in a conditioned place preference assay. Collectively, these stereoisomers represent new lead compounds for further investigation in the development of safer opioid analgesics.National Institute on Drug Abuse (R01 DA18832)National Institute on Drug Abuse (R01 DA032928

Direct Phenotypic Screening in Mice: Identification of Individual, Novel Antinociceptive Compounds from a Library of 734 821 Pyrrolidine Bis-piperazines

The hypothesis in the current study is that the simultaneous direct in vivo testing of thousands to millions of systematically arranged mixture-based libraries will facilitate the identification of enhanced individual compounds. Individual compounds identified from such libraries may have increased specificity and decreased side effects early in the discovery phase. Testing began by screening ten diverse scaffolds as single mixtures (ranging from 17 340 to 4 879 681 compounds) for analgesia directly in the mouse tail withdrawal model. The “all X” mixture representing the library TPI-1954 was found to produce significant antinociception and lacked respiratory depression and hyperlocomotor effects using the Comprehensive Laboratory Animal Monitoring System (CLAMS). The TPI-1954 library is a pyrrolidine bis-piperazine and totals 738 192 compounds. This library has 26 functionalities at the first three positions of diversity made up of 28 392 compounds each (26 × 26 × 42) and 42 functionalities at the fourth made up of 19 915 compounds each (26 × 26 × 26). The 120 resulting mixtures representing each of the variable four positions were screened directly in vivo in the mouse 55 °C warm-water tail-withdrawal assay (ip administration). The 120 samples were then ranked in terms of their antinociceptive activity. The synthesis of 54 individual compounds was then carried out. Nine of the individual compounds produced dose-dependent antinociception equivalent to morphine. In practical terms what this means is that one would not expect multiexponential increases in activity as we move from the all-X mixture, to the positional scanning libraries, to the individual compounds. Actually because of the systematic formatting one would typically anticipate steady increases in activity as the complexity of the mixtures is reduced. This is in fact what we see in the current study. One of the final individual compounds identified, TPI 2213-17, lacked significant respiratory depression, locomotor impairment, or sedation. Our results represent an example of this unique approach for screening large mixture-based libraries directly in vivo to rapidly identify individual compounds

Effects of eluted components from 4-META/MMA-TBB adhesive resin sealer on osteoblastic cell proliferation

Background/purpose: Adhesive resin sealer systems are applied to seal root-canal systems more effectively through the formation of a resin impregnation layer. The purpose of this study was to investigate the effects of eluted components of the adhesive, Super-Bond sealer (SBS), on the proliferation of osteoblastic cells in vitro. Materials and methods: The standard powder:liquid ratio according to the manufacturer\u27s instructions was used to produce a cylindrical block of SBS (5 mm in diameter, 10 mm long) for this elution study. The resin block was placed on a 100-mm culture dish. Osteoblastic cells were seeded at a density of 4 × 10 6 in α-minimum essential medium containing 10% fetal bovine serum and cultured in a humidified incubator. After 3 days of culture with or without SBS, cells were retrieved and lysed according to the manufacturer\u27s instructions. The cellular events induced by the eluted components from SBS were analyzed using an antibody assay for mitogen-activated protein kinases (MAPKs) and a 3-(4,5-dimethylthyazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Furthermore, the concentration of boron, a component of the catalyst, tri-n-butyl borane (TBB), was analyzed using inductively coupled plasma optical emission spectrometry. Results: Expression of MAPKs increased after SBS application. The MTT assay indicated that TBB, one of the components of SBS, accelerated the proliferation of osteoblastic cells. Values of boron were 1.66 ± 0.37 and 1.74 ± 0.30 ppm in cells cultured with and without FBS, respectively. Conclusions: The eluted components from SBS can increase the expression of some MAPKs related to osteoblastic cell proliferation and differentiation in vitro. Both the elution experiment and treatment of cell culture with SBS components indicated that the boron originating from TBB is likely to be responsible for activation of the proliferation of osteoblastic cells

Recent Innovations & Daily Problems. A new prosthesis in inguinal hernia repair:preliminary results of a pilot study.

Introduction: Elective surgery for inguinal hernia is affected by very low mortality « 1 per 10000 operation); in contrast, when surgery is carried out for complicated inguinal hernia, risks of postoperative complication are higher. TAPP is a world-wide accepted surgical practice in the treatment of elective bilateral or recurrent inguinal hernia, above all in young patients. Few exploratory studies were published on laparoscopic approach in the treatment of urgent complicated inguinal hernia. Aim of this study was to analyze feasibility (operative time, conversion rate), safety (postoperative morbidity, length of hospital stay) and quality of life (acute and chronic pain, return to work) of trans-abdominal pre-peritoneal laparoscopic hernia repair in acute incarcerated inguinal hernia. Rationale of laparoscopic trans-abdominal approach is the easier hernia reduction under vision and a better exploration of the abdominal cavity. Methods: from September 2012 to September 2013, 15 consecutive patients admitted in emergency at the Division of General Surgery of University "Sapienza", Polo Pontino, for acute incarcerated inguinal hernia were submitted to TAPP using 3 trocars (1 of 10 mm and 2 of 5mm) and polyester prosthesis fixed by fibrin glue. Exclusion criteria for laparoscopic approach were age III, previous abdominal surgery, signs of strangulated hernia. All of them were evaluated for operative time, conversion rate, postoperative morbidity, organ resection or other surgery required. All patients were scored for pain by Visual Analogic Scale (VAS) during postoperative in hospital stay at 7 days, 1,6 and 12 months after surgery. Results: median follow-up was 16 months and 12 as minimum. In all cases reduction of hernia was always possible and none conversion to open surgery was recorded, median operative time was 89 minutes (55-137 as range), omental resection was carried out in one patient (6,6%), no other organ resections needed, whereas contralateral hernia was diagnosed and repaired at the same time in 4 patients (26,6%). No major complications were observed, median blood loss was 100 ml, minor morbidity was contained to 18% represented by fever and wound infection of surgical umbilical scar. Median in hospital stay was 1,5 days with 1-5 days as range. Postoperative median acute pain, measured by visual analogic scale (VAS), was 2 (range:0-4), none patient referred any pain during follow-up. Median time of return to work was 6,5 days, ranged between 3 to 15 days. Patients' compliance to treatment and to follow-up was complete as well their satisfaction. Conclusions: In centres skilled for laparoscopy in emergency, TAPP could be considered a feasible and safe technique. In well-selected patients (especially if emolled in controlled clinical trial) TAPP could represent an alternative surgical approach for complicated incarcerated inguinal hernia to conventional open surgery even in urgency. The main advantages of laparoscopic approach are the ability to perform surgical hernia reduction under vision, a better exploration and evaluation of abdominal cavity and diagnosis and treatment of eventual contralateral defect of wall, otherwise often missed. Finally, the good control of acute and chronic pain, faster return to normal activity and work, better aesthetic results contributed to total satisfaction and compliance of the patients

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京都大学0048新制・論文博士理学博士論理博第85号新制||理||45(附属図書館)933(主査)教授 波多野 博行, 教授 田中 正三, 教授 後藤 良造学位規則第5条第2項該当Kyoto UniversityDA