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1.
Proc Biol Sci ; 287(1938): 20202129, 2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33171091

RESUMEN

Since their discovery in 1927, the phylogenetic status of the Myanmar amphipithecines has been highly debated. These fossil primates are recognized either as anthropoids or as adapiform strepsirrhines. This uncertainty was largely the consequence of a limited fossil record consisting mostly of jaw fragments but lacking the critical cranial elements that might resolve this debate. We report here cranial remains associated with an ulna from a single individual pertaining to the amphipithecine Ganlea megacanina. In addition to anthropoid-like dentognathic characters, Ganlea displays several ulna and skull features that testify to its anthropoid affinities (e.g. short subvertically oriented lacrimal duct, lacrimal foramen and bone inside the orbit, maxillary contribution to the lower orbital rim, fused metopic suture). By contrast to crown anthropoids, however, Ganlea lacks postorbital closure, confirming that postorbital closure appeared later than many anthropoid dentognathic characters and evolved convergently in extant tarsiers and anthropoids. Thus, amphipithecines must now be recognized as stem anthropoids offering a unique window on the early evolution of cranial and skeletal features in anthropoids, and reinforcing the hypothesis of an origin and early diversification of anthropoids in Asia.


Asunto(s)
Evolución Biológica , Haplorrinos , Animales , Asia , Fósiles , Mianmar , Órbita , Filogenia , Primates , Cráneo
2.
Int J Dent Hyg ; 16(2): e96-e102, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29120096

RESUMEN

OBJECTIVES: This study aimed to assess the oral health and the prevalence of pre-existing oral colonization with respiratory pathogens in dependent elderly, and whether these factors influence pneumonia development. MATERIALS AND METHODS: Participants residing in a long-term care facility received bedside oral examinations, and information on their oral health (caries status, calculus index and debris index) was obtained. Samples from the tongue and teeth were collected at baseline and at time of pneumonia development. Sputum was collected at the time of pneumonia diagnosis. Samples were assessed for Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pneumoniae by polymerase chain reaction. RESULTS: This was a 1-year longitudinal study of 60 dependent elderly (mean age: 64.2 ± 14.1 years). Seventeen patients (28.3%) developed pneumonia. The mean Decayed, Missing and Filled Teeth and Simplified Oral Hygiene Index were 22.8 ± 9.2 and 4.0 ± 1.0, respectively. At baseline, 48.3% were orally colonized with ≥1 respiratory pathogens. The presence of H. influenzae (P = .002) and P. aeruginosa (P = .049) in the sputum was significantly associated with their colonization on the tongue at baseline. In the bivariate analyses, pneumonia development was associated with naso-gastric feeding tube (P = .0001), H. influenzae (P = .015) and P. aeruginosa (P = .003) tongue colonization at baseline and calculus index (P = .002). Multivariate analyses revealed that calculus index (P = .09) and the presence of tracheostomy (P = .037) were associated with pneumonia. CONCLUSIONS: The calculus amount and tongue colonization with respiratory pathogens are risk factors for pneumonia development. Oral hygiene measures to remove tongue biofilm and calculus may reduce pneumonia development.


Asunto(s)
Placa Dental/microbiología , Estado de Salud , Casas de Salud , Salud Bucal , Neumonía Bacteriana/microbiología , Esputo/microbiología , Lengua/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Biopelículas , Índice CPO , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Índice de Higiene Oral , Reacción en Cadena de la Polimerasa , Estudios Prospectivos , Factores de Riesgo , Singapur
3.
J Med Chem ; 42(11): 1975-81, 1999 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-10354405

RESUMEN

To examine the effect of changing the amide bond of anandamide (5, AN) to a less hydrolyzable moiety, analogues 1a-1l, 2a-2c, 3a-3c, and 4a-4h were synthesized from commercially available arachidonyl alcohol or arachidonic acid and tested for their pharmacological activity. Arachidonyl ethers 1a-1k were obtained through the coupling of the arachidonyl mesylate (6) (generated from the mesylation of arachidonyl alcohol) with the appropriate alcohol in potassium hydroxide. Arachidonyl ether 1l was obtained through the phase-transfer coupling of arachidonyl alcohol with 2-(2-iodoethoxy)tetrahydropyran (which was generated from its bromide) followed by cleavage of the tetrahydropyran group with Dowex resin. Arachidonyl carbamates 2a-2c were obtained through the coupling of arachidonyl alcohol with the appropriate isocyanates. Norarachidonyl carbamates 3a-3c and ureas 4a-4h were obtained through the coupling of the norarachidonyl isocyanate (generated from arachidonic acid using diphenyl phosphorazidate and triethylamine upon heating) with the appropriate alcohols and amines, respectively. AN analogues 1-3 have shown poor binding affinities to the CB1 receptor and fail to produce significant pharmacological effect at doses up to 30 mg/kg. Several ether analogues 1 were also evaluated in the CB2 binding assay and were found to be of low affinity. However, norarachidonyl urea analogues 4 have shown generally good binding affinities to the CB1 receptor (Ki = 55-746 nM) and pharmacological activity with AN-like profiles. The most potent analogue of this series is the 2-fluoroethyl analogue 4f which binds 2 times better than AN and was more active in several mouse behavioral assays. It was also observed that urea analogues 4a and 4g, which have weak binding affinities to the CB1 receptor (Ki = 436 and 347 nM, respectively), produced surprisingly potent pharmacological activity. These urea analogues have also shown hydrolytic stability toward the amidase enzymes, responsible for the primary degradation pathway of anandamide, in binding affinity assays in the absence of the enzyme inhibitor PMSF.


Asunto(s)
Ácidos Araquidónicos/síntesis química , Carbamatos/síntesis química , Urea/análogos & derivados , Urea/síntesis química , Analgésicos no Narcóticos/síntesis química , Analgésicos no Narcóticos/química , Analgésicos no Narcóticos/metabolismo , Analgésicos no Narcóticos/farmacología , Animales , Ácidos Araquidónicos/química , Ácidos Araquidónicos/metabolismo , Ácidos Araquidónicos/farmacología , Temperatura Corporal/efectos de los fármacos , Cannabinoides/metabolismo , Carbamatos/química , Carbamatos/metabolismo , Carbamatos/farmacología , Endocannabinoides , Hidrólisis , Ligandos , Ratones , Actividad Motora/efectos de los fármacos , Alcamidas Poliinsaturadas , Ensayo de Unión Radioligante , Receptores de Cannabinoides , Receptores de Droga/metabolismo , Relación Estructura-Actividad , Urea/química , Urea/metabolismo , Urea/farmacología
4.
Br J Pharmacol ; 132(2): 525-35, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11159703

RESUMEN

1. The activities of a number of side-chain analogues of delta-8-tetrahydrocannabinol (Delta(8)-THC) in rat cerebellar membrane preparations were tested. 2. The affinities of each compound for the CB(1) receptor were compared by their respective abilities to displace [(3)H]-SR141716A and their efficacies compared by stimulation of [(35)S]-GTPgammaS binding. 3. It was found that the affinities varied from 0.19+/-0.03 nM for 3-norpentyl-3-[6'-cyano,1',1'-dimethyl]hexyl-Delta(8)-THC to 395+/-66.3 nM for 5'-[N-(4-chlorophenyl)]-1',1'-dimethyl-carboxamido-Delta(8)-THC. 4. The efficacies of these compounds varied greatly, ranging from the very low efficacy exhibited to acetylenic compounds such as 1'-heptyn-Delta(8)-THC and 4'-octyn-Delta(8)-THC to higher efficacy compounds such as 5'-(4-cyanophenoxy)-1',1'-dimethyl-Delta(8)-THC and 5'-[N-(4-aminosulphonylphenyl)]-1',1' dimethyl-carboxamido Delta(8)-THC. All agonist activities were antagonized by the CB(1)-selective antagonist SR141716A. 5. It was found that a ligand's CB(1) affinity and efficacy are differentially altered by modifications in the side-chain. Decreasing the flexibility of the side-chain reduced efficacy but largely did not alter affinity. Additionally, the positioning of electrostatic moieties, such as cyano groups, within the side-chain also has contrasting effects on these two properties. 6. In summary, this report details the characterization of a number of novel Delta(8)-THC analogues in rat cerebellar membranes. It provides the first detailed pharmacological analysis of how the inclusion of electrostatic moieties in the side-chain and also how alteration of the side-chain's flexibility may differentially affect a CB(1) cannabinoid receptor ligand's affinity and efficacy.


Asunto(s)
Dronabinol/análogos & derivados , Dronabinol/farmacología , Receptores de Droga/efectos de los fármacos , Receptores de Droga/metabolismo , Animales , Células CHO , Ácidos Carboxílicos/síntesis química , Ácidos Carboxílicos/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Cerebelo/efectos de los fármacos , Cerebelo/metabolismo , Cricetinae , Ciclohexanoles/farmacología , Dronabinol/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Técnicas In Vitro , Masculino , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley , Receptores de Cannabinoides , Relación Estructura-Actividad
5.
Am J Trop Med Hyg ; 56(5): 566-72, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9180609

RESUMEN

Despite a growing body of evidence predominantly, but not exclusively, from Thailand suggesting that the risk of developing dengue shock syndrome (DSS) is greatest following an anamnestic dengue infection, particularly if the most recent infection was with dengue 2 virus, there continues to be debate about the justification for these claims. This report describes a five-year, prospective study in two townships (suburbs) in Yangon (Rangoon) Myanmar (Burma) in which attempts were made to confirm the data from an earlier prospective study in Thailand and to address some of the criticism of earlier studies. This investigation found the incidence of anamnestic dengue infections in DSS patients to be significantly higher than in the community from which they were drawn and a significantly higher risk of developing DSS following an anamnestic infection (particularly with dengue 2 virus) than following a primary infection with any serotype.


Asunto(s)
Dengue/complicaciones , Niño , Preescolar , Humanos , Estudios Prospectivos , Factores de Riesgo
6.
Eur J Pharmacol ; 377(1): 117-25, 1999 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-10448934

RESUMEN

The aim of this study was to characterize the activity of the cannabinoid CB2 receptor selective antagonist, N-[(1S)-endo-1,3,3-trimethyl bicyclo[2.2.1] heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazo le-3-carboxamide] (SR144528) in a number of biochemical assays and to look for evidence of cannabinoid CB2 receptors in the rat central nervous system. SR144528 displaced [3H]CP 55,940 ((-)-3-[2-hydroxyl-4-(1,1-dimethylheptyl)-phenyl]-4-[3-hydroxyprop yl]cyclohexan-1-ol) from binding sites in CB2- and CB1-transfected cells (Ki = 0.67+/-0.30 and 33.0+/-5.09 nM) and from rat cerebellum and whole brain membrane homogenates (Ki = 54.7+/-9.70 and 54.8+/-7.86 nM). In the GTPgammaS binding assay, SR144528 antagonized a number of cannabinoid receptor agonists (K(B) values ranging from 26.3 to 76.6 nM) in rat cerebellar membranes and in rat whole brain membranes (K(B) = 50.8 nM). SR144528 also antagonized CP 55,940-stimulated GTPgammaS binding in a CB2-expressing cell line (K(B) = 6.34 nM). In Xenopus oocytes co-expressing the CB1 receptor and G-protein coupled inwardly rectifying K+ channels (GIRK 1/4), SR144528 antagonized WIN 55212-2((R)-(+)-[2,3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrolo [1,2,3-de]-1,4-benzoxazin-6-yl](1-naphthalenyl)methanone) -stimulated K+ currents (K(B) = 558 nM). In summary, this report characterizes the cannabinoid CB2 receptor-selective cannabinoid antagonist, SR144528, and additionally suggests an absence of cannabinoid CB2 receptors in the rat central nervous system, an observation confirmed by Northern blot.


Asunto(s)
Canfanos/farmacología , Canales de Potasio de Rectificación Interna , Pirazoles/farmacología , Receptor Cannabinoide CB2 , Receptores de Droga/antagonistas & inhibidores , Animales , Benzoxazinas , Unión Competitiva , Northern Blotting , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Canfanos/metabolismo , Sistema Nervioso Central/efectos de los fármacos , Sistema Nervioso Central/metabolismo , Relación Dosis-Respuesta a Droga , Proteínas de Unión al GTP/fisiología , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Humanos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Membranas/efectos de los fármacos , Membranas/metabolismo , Morfolinas/farmacología , Naftalenos/farmacología , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Oocitos/fisiología , Canales de Potasio/genética , Canales de Potasio/fisiología , Pirazoles/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ensayo de Unión Radioligante , Ratas , Ratas Sprague-Dawley , Receptores de Cannabinoides , Receptores de Droga/genética , Distribución Tisular , Xenopus laevis
7.
Trans R Soc Trop Med Hyg ; 86(4): 438-42, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1332222

RESUMEN

During 1984, 1548 children were admitted to the Yangon [Rangoon] Children's Hospital in Myanmar [Burma] with haemorrhagic fever. No evidence of recent dengue infection was found in 577 of the 803 children from whom paired sera were obtained, raising the possibility of reappearance of Chikungunya virus infection in Myanmar. An enzyme-linked immunosorbent assay (ELISA) for the detection of anti-Chikungunya virus immunoglobulin M (IgM) antibody was prepared and standardized using only reagents which are commercially available or which could be prepared without the use of sophisticated equipment. While there was 90% agreement between haemagglutination inhibition (HI) tests and the IgM ELISA in the diagnosis of acute Chikungunya virus infections, 12 additional patients with stationary anti-Chikungunya virus HI antibody titres could be identified as having acute Chikungunya infections using the ELISA. Furthermore, the ELISA could identify twice as many patients (31/103) at the time of admission to hospital as the HI test (15/103). There was no false positive IgM reaction with the ELISA which could be attributed to the presence of rheumatoid factor. Using the test, 103 of a sample of 163 children who presented to the Yangon Children's Hospital with fever/haemorrhagic fever were diagnosed as Chikungunya patients, 4 had possible dual Chikungunya and dengue infections, 16 had dengue, 30 had neither Chikungunya nor dengue infections, and a definitive diagnosis could not be made for 10 patients. Routine use of the ELISA would alert authorities to future outbreaks of Chikungunya virus infection and avoid admission to hospital of patients with a non-life-threatening viral disease.


Asunto(s)
Anticuerpos Antivirales/análisis , Virus Chikungunya/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina M/análisis , Infecciones por Togaviridae/inmunología , Niño , Preescolar , Brotes de Enfermedades , Humanos , Tiempo de Internación , Mianmar/epidemiología , Infecciones por Togaviridae/epidemiología
8.
Drug Alcohol Depend ; 60(2): 133-40, 2000 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10940540

RESUMEN

The N-1 alkyl side chain of the aminoalkylindole analogues (AAI) has been implicated as one of a three-point interaction with the cannabinoid CB(1) receptor. In this study, the morpholinoethyl of WIN 55,212-2 was replaced with carbon chains of varying lengths ranging from a methyl to heptyl group. Additional groups were added to the naphthoyl and the C2 positions of the molecule. These structural changes revealed that high affinity binding to the CB(1) and CB(2) receptors requires an alkyl chain length of at least three carbons with optimum binding to both receptors occurring with a five carbon side chain. An alkyl chain of 3-6 carbons is sufficient for high affinity binding; however, extension of the chain to a heptyl group results in a dramatic decrease in binding at both receptors. The unique structure of the cannabimimetic indoles provides a useful tool to define the ligand-receptor interaction at both cannabinoid receptors and to refine proposed pharmacophore models.


Asunto(s)
Cannabinoides/metabolismo , Dronabinol/metabolismo , Indoles/metabolismo , Receptores de Droga/metabolismo , Animales , Benzoxazinas , Células CHO , Cannabinoides/química , Cricetinae , Dronabinol/química , Humanos , Indoles/química , Morfolinas/química , Morfolinas/metabolismo , Naftalenos/química , Naftalenos/metabolismo , Receptores de Cannabinoides , Relación Estructura-Actividad
9.
Biosens Bioelectron ; 26(8): 3666-9, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21367597

RESUMEN

This paper unveils a platform to develop a compact, simple, reusable and disposable, and cost effective hand-held urinalysis device for home-health-care and doctor's office uses. A polymeric optical waveguide and colorimetric absorption were used as an optical sensor and sensing mode, respectively. The results of the tests show that the device was able to deliver quantitative results with the detection limits better than 0.1g/L, 0.2g/L, 0.025 g/L, and 0.1g/L for glucose, creatinine, albumin and total protein, respectively. There are some superiorities of this device as compared to the dip-stick counterpart, that are, better sensitivity, ability to deliver quantitative results and reusability. The device is being further miniaturized to use a LED and photodiode as a light source and detector, respectively. It is believed the device has potential for early diagnostic and wellness monitoring tool.


Asunto(s)
Técnicas Biosensibles/instrumentación , Polímeros/química , Urinálisis/instrumentación , Albuminuria/diagnóstico , Glucemia/análisis , Calibración , Creatinina/orina , Glucosuria/diagnóstico , Humanos , Proteinuria/diagnóstico
10.
Ann Trop Paediatr ; 6(1): 27-9, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2428288

RESUMEN

The effect of oral rehydration (OR) has been well established in the management of dehydration in acute childhood diarrhoea. Many authors have been trying to find additives of all types which would be effective in retaining oral fluids and promoting their active absorption into the circulation. Any agent which will effectively reduce oral rehydration requirements should be considered for prospective studies. Amongst the traditional medicines, it was noticed that sodium tetraborate (borax) and alum reduced appreciably the fluid requirement in many cases of acute childhood diarrhoea. This traditional usage of these chemicals without any noticeable side effects has been described for centuries. During preliminary observations on 26 of our children given these salts no side effects were detected.


Asunto(s)
Compuestos de Alumbre , Aluminio/uso terapéutico , Boratos/uso terapéutico , Diarrea Infantil/terapia , Diarrea/terapia , Sulfatos/uso terapéutico , Aluminio/farmacología , Bicarbonatos/uso terapéutico , Peso Corporal/efectos de los fármacos , Boratos/farmacología , Preescolar , Quimioterapia Combinada , Glucosa/uso terapéutico , Humanos , Lactante , Cloruro de Potasio/uso terapéutico , Cloruro de Sodio/uso terapéutico , Sulfatos/farmacología , Factores de Tiempo
11.
Bioorg Med Chem ; 7(12): 2905-14, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10658595

RESUMEN

The synthesis and pharmacology of 15 1-deoxy-delta8-THC analogues, several of which have high affinity for the CB2 receptor, are described. The deoxy cannabinoids include 1-deoxy-11-hydroxy-delta8-THC (5), 1-deoxy-delta8-THC (6), 1-deoxy-3-butyl-delta8-THC (7), 1-deoxy-3-hexyl-delta8-THC (8) and a series of 3-(1',1'-dimethylalkyl)-1-deoxy-delta8-THC analogues (2, n = 0-4, 6, 7, where n = the number of carbon atoms in the side chain-2). Three derivatives (17-19) of deoxynabilone (16) were also prepared. The affinities of each compound for the CB1 and CB2 receptors were determined employing previously described procedures. Five of the 3-(1',1'-dimethylalkyl)-1-deoxy-delta8-THC analogues (2, n = 1-5) have high affinity (Ki = < 20 nM) for the CB2 receptor. Four of them (2, n = 1-4) also have little affinity for the CB1 receptor (Ki = > 295 nM). 3-(1',1'-Dimethylbutyl)-1-deoxy-delta8-THC (2, n = 2) has very high affinity for the CB2 receptor (Ki = 3.4 +/- 1.0 nM) and little affinity for the CB1 receptor (Ki = 677 +/- 132 nM).


Asunto(s)
Cannabinoides/metabolismo , Dronabinol/análogos & derivados , Receptores de Droga/metabolismo , Animales , Línea Celular , Dronabinol/síntesis química , Dronabinol/química , Dronabinol/metabolismo , Humanos , Técnicas In Vitro , Cinética , Ligandos , Espectroscopía de Resonancia Magnética , Receptores de Cannabinoides , Relación Estructura-Actividad
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