RESUMO
Aerosols are one of the significant external sources of soluble reactive nitrogen to the surface ocean and their deposition affects the primary productivity. Owing to rapid industrialization over South and Southeast Asia, an increasing trend in atmospheric pollutants was observed over the northern Indian Ocean (NIO). To assess the contribution of the aeolian supply of inorganic nitrogen to the NIO, the available compositional data of marine aerosols collected over this basin between 2001 and 2020 were compiled. Based on the observed relationship of mass load, and particulate nitrate and ammonium concentrations with the corresponding satellite-derived anthropogenic aerosol optical depth (AAOD), the temporal, spatial, and long-term variabilities were derived for the past two decades. In particular, high aerosol mass load, nitrate and ammonium levels were observed in the coastal aerosols of peninsular India during fall and winter and they were low in summer. The atmospheric input of inorganic nitrogen to the Arabian Sea is higher (AS; 1.7 TgN per year) compared to that of the Bay of Bengal (BoB; 0.9 TgN per year) and accounts for â¼30% of the total external sources of nitrogen to the NIO. The new production, supported by external sources of nitrogen, contributes to â¼23 and 53% of export production to the oxygen minimum zone (OMZ) in the AS and BoB respectively. A significant rate of increase in the aerosol mass load (0.05-1.67 µg per m3 per year), and nitrate (0.003-0.04 µg per m3 per year) and ammonium (0.006-0.11 µg per m3 per year) concentrations was observed between 2001 and 2020, likely because of the increased emission of anthropogenic pollutants over South and Southeast Asia and their subsequent long-range atmospheric transport to the NIO. Overall, these results suggest that an enhanced contribution of atmospheric nitrogen may potentially increase (1) the N/P ratio of the surface ocean that impacts phytoplankton composition, (2) export production to the OMZ leads to intensification, and (3) sequestration of atmospheric CO2. A decrease in primary production due to global warming is reported due to a decrease in vertical nutrient supply; however, the increase in atmospheric deposition of nutrients may compensate for this. Therefore, ocean models must be coupled with atmospheric models to better constrain the oceanic response to climate change in the NIO.
Assuntos
Poluentes Atmosféricos , Compostos de Amônio , Poluentes Ambientais , Nitrogênio , Oceano Índico , Monitoramento Ambiental/métodos , Nitratos , Dióxido de Carbono , Aerossóis/análise , Poeira , Oxigênio , Poluentes Atmosféricos/análiseRESUMO
Perennial increase in atmospheric pollution over the Bay of Bengal (BoB) and South China Sea is reported due to increase in human population and industrial activity in South and Southeast Asia. Based on total aerosol optical depth (AOD) derived from MODIS (moderate resolution imaging resolution imaging spectroradiometer), natural and anthropogenic fractions were derived. The seasonality and spatial variability in rate of increase in total, natural, and anthropogenic AOD fractions were examined over the BoB using data collected between 2001 and 2019. Both total and anthropogenic AOD displayed statistically significant rate of increase in the northwest BoB (NWB) and western coastal BoB (WCB) regions during 2001 to 2019 whereas the long-term changes are insignificant in the other regions of BoB. Significant increase in AOD in the NWB and WCB regions is mainly contributed by dominant outflow of anthropogenic emissions from Indo-Gangetic Plain (IGP) area of Indian subcontinent. The magnitude of AOD decreased by half from northern BoB to equatorial region due to increase in distance from the source region. The contribution of anthropogenic AOD was >70% to total AOD with higher contribution during winter and lower during summer. The rate of increase in both total and anthropogenic AOD was close to 0.104 and 0.099 per decade in the NWB and 0.069 and 0.059 per decade in the WCB region between 2001 and 2019. The rate of increase in total and anthropogenic AOD decreased from 2001-2009 (0.164 and 0.115 per decade respectively) to 2010-2019 (0.068 and 0.076 per decade respectively) in the NWB region. Significant increase in anthropogenic AOD by 50 and 30% was observed during El Niño and La Niña periods respectively than normal year in both northwest BoB (NWB) and western coastal (WCB) regions due to change in strength and direction of winds. Although some fraction of anthropogenic AOD is found over the entire BoB, significant rate of increase in anthropogenic AOD is found only about 23% of the area of BoB than hitherto reported as entire BoB. The impact of atmospheric deposition of anthropogenic aerosols on biogeochemical processes, such as primary production and ocean acidification, needs further evaluation.
Assuntos
Poluentes Ambientais , Aerossóis , Baías , Humanos , Concentração de Íons de Hidrogênio , Água do MarRESUMO
Presented here is the clinical and hemodynamic profile of 147 patients, above the age of 18 with tetralogy of Fallot. Cardiac catheterization and selective cineangiocardiography were performed in all. Infundibular pulmonary stenosis, a subaortic large infracristal ventricular septal defect, mitral-aortic fibrous continuity and equal pressures in both the ventricles and aorta were considered mandatory for the diagnosis of tetralogy of Fallot. Cardiac enlargement was seen in 25.8 per cent of the patients, and 15.6 per cent were in congestive cardiac failure; 9.5 per cent had systemic hypertension, and aortic regurgitation was present in 6.7 per cent. A reticular pattern in the lung fields due to bronchial collaterals was seen in 23.1 per cent. The incidence of right aortic arch (19.9 per cent), absent left pulmonary artery (2.8 per cent), absent right pulmonary artery (0.7 per cent) and dextrocardia (1.4 per cent) is brought out. The right atrial mean pressure was increased in 4.8 per cent and a prominent "a" wave greater than 10 mm Hg was present in 10.9 per cent. The right ventricular end-diastolic pressure was increased in 23.8 per cent and the left ventricular end-diastolic pressure in 25.9 per cent of the patients.
Assuntos
Tetralogia de Fallot/diagnóstico , Adolescente , Adulto , Insuficiência da Valva Aórtica/etiologia , Pressão Sanguínea , Volume Cardíaco , Cardiomegalia/etiologia , Circulação Colateral , Feminino , Insuficiência Cardíaca/etiologia , Hemodinâmica , Humanos , Hipertensão/etiologia , Masculino , Tetralogia de Fallot/complicações , Tetralogia de Fallot/fisiopatologiaRESUMO
A DNA vaccine expressing glycoprotein C (gC) of bovine herpesvirus-1 (BHV-1) was evaluated for inducing immunity in bovines. The plasmid encoding gC of BHV-1 was injected six times intramuscularly or intradermally into calves at monthly intervals. After immunization by both routes neutralizing antibody and lymphoproliferative responses developed. The responses in the intradermally immunized calves were better than those in calves immunized intramuscularly. However, the intradermal (i.d.) route was found to be less efficacious when protection against BHV-1 challenge was compared. Following intranasal BHV-1 challenge, all immunized calves demonstrated a rise in IgG antibody titre on day 3, indicating an anamnestic response. The control non-immunized calf developed a neutralizing antibody response on day 7 post-challenge. The immunized calves showed a slight rise in temperature and mild clinical symptoms after challenge. The intramuscularly immunized calves showed earlier clearance of challenge virus compared with intradermally immunized calves. These results indicate that DNA immunization with gC could induce neutralizing antibody and lymphoproliferative responses with BHV-1 responsive memory B cells in bovines. However, the immunity developed was not sufficient to protect calves completely from BHV-1 challenge.
Assuntos
Doenças dos Bovinos/imunologia , Infecções por Herpesviridae/veterinária , Herpesvirus Bovino 1/imunologia , Vacinação/veterinária , Vacinas de DNA/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Bovinos , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/virologia , Divisão Celular/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Infecções por Herpesviridae/sangue , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/prevenção & controle , Herpesvirus Bovino 1/genética , Injeções Intradérmicas/veterinária , Injeções Intramusculares/veterinária , Leucócitos Mononucleares/imunologia , Masculino , Testes de Neutralização/veterinária , Vacinas de DNA/administração & dosagem , Proteínas do Envelope Viral/genética , Carga Viral/veterináriaRESUMO
PURPOSE: To study the optic disc size in eyes with ocular hypertension (OHT) in comparison to primary open-angle glaucoma (POAG) and normals. METHODS: Optic disc photographs obtained with the Nidek 3dx NM camera were digitized (Nikon coolscan) and disc area calculated using Littmann correction in a randomly chosen eye of 28 OHT, 42 POAG and 30 normal subjects. OHT was defined as increased intraocular pressure with no disc or field changes suggestive of glaucoma with open angles. RESULTS: The optic disc area in OHT was 9.47 +/- 1.09 mm2; 12.27 +/- 2.87 mm2 in POAG; and 12.11 +/- 2.83 mm2 in normal individuals. CONCLUSION: Using magnification corrected morphometry and the criteria for OHT diagnosis, the optic disc area in OHT was significantly smaller (p < 0.0001) in POAG and normals.
Assuntos
Hipertensão Ocular/patologia , Disco Óptico/patologia , Glaucoma de Ângulo Aberto/patologia , Humanos , Pressão Intraocular , Fotografação , Prognóstico , Campos VisuaisAssuntos
Anormalidades Múltiplas , Cardiopatias Congênitas/complicações , Baço/anormalidades , Criança , Pré-Escolar , Feminino , Humanos , Lactente , MasculinoRESUMO
The adenylyl and guanylyl cyclases catalyze the formation of 3', 5'-cyclic adenosine or guanosine monophosphate from the corresponding nucleoside 5'-triphosphate. The guanylyl cyclases, the mammalian adenylyl cyclases, and their microbial homologues function as pairs of homologous catalytic domains. The crystal structure of the rat type II adenylyl cyclase C2 catalytic domain was used to model by homology a mammalian adenylyl cyclase C1-C2 domain pair, a homodimeric adenylyl cyclase of Dictyostelium discoideum, a heterodimeric soluble guanylyl cyclase, and a homodimeric membrane guanylyl cyclase. Mg2+ATP or Mg2+GTP were docked into the active sites based on known stereochemical constraints on their conformation. The models are consistent with the activities of seven active-site mutants. Asp-310 and Glu-432 of type I adenylyl cyclase coordinate a Mg2+ ion. The D310S and D310A mutants have 10-fold reduced Vmax and altered [Mg2+] dependence. The NTP purine moieties bind in mostly hydrophobic pockets. Specificity is conferred by a Lys and an Asp in adenylyl cyclase, and a Glu, an Arg, and a Cys in guanylyl cyclase. The models predict that an Asp from one domain is a general base in the reaction, and that the transition state is stabilized by a conserved Asn-Arg pair on the other domain.
Assuntos
Adenilil Ciclases/química , Adenilil Ciclases/metabolismo , Guanilato Ciclase/química , Guanilato Ciclase/metabolismo , Modelos Moleculares , Adenilil Ciclases/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação/genética , Catálise , Colforsina/metabolismo , Primers do DNA/genética , Guanilato Ciclase/genética , Cinética , Metais/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Nucleotídeos/metabolismo , Conformação Proteica , Ratos , Homologia de Sequência de Aminoácidos , Especificidade por SubstratoRESUMO
The coagglutination test was standardised using Staphylococcus aureus strain Cowan I (containing Protein A) coated with anti-goat pox serum for the detection of goat pox antigen of infected goat skin or kid kidney cell culture antigen. Agglutination was observed within 10 seconds in virus dilutions up to 10(-6). As the test is easy to perform it can be used for rapid diagnosis of goat pox.
Assuntos
Doenças das Cabras/diagnóstico , Infecções por Poxviridae/veterinária , Testes de Aglutinação , Animais , Antígenos Virais/análise , Células Cultivadas , Cabras , Rim/citologia , Poxviridae/imunologia , Infecções por Poxviridae/diagnóstico , Pele/microbiologiaRESUMO
Phosphoinositide kinases play central roles in signal transduction by phosphorylating the inositol ring at specific positions. The structure of one such enzyme, type IIbeta phosphatidylinositol phosphate kinase, reveals a protein kinase ATP-binding core and demonstrates that all phosphoinositide kinases belong to one superfamily. The enzyme is a disc-shaped homodimer with a 33 x 48 A basic flat face that suggests an electrostatic mechanism for plasma membrane targeting. Conserved basic residues form a putative phosphatidylinositol phosphate specificity site. The substrate-binding site is open on one side, consistent with dual specificity for phosphatidylinositol 3- and 5-phosphates. A modeled complex with membrane-bound substrate and ATP shows how a phosphoinositide kinase can phosphorylate its substrate in situ at the membrane interface.
Assuntos
Fosfotransferases (Aceptor do Grupo Álcool)/química , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cristalografia , Dimerização , Escherichia coli , Dados de Sequência Molecular , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Frações Subcelulares/enzimologia , Especificidade por SubstratoRESUMO
Resolution of the racemic amino alcohol derivatives 1-6 is readily achieved to obtain enantiomerically enriched compounds using chiral 1,1'-bi-2-naphthol and boric acid in solvents such as CH(3)CN, THF, and MeOH. Purification of the diastereomeric mixture 7 has also been carried out following this method. The corresponding intermediate ammonium borate complexes were also characterized by X-ray diffraction methods.
RESUMO
Two new sphingolipids, (2S,3S,4R)-1,3,4-trihydroxy-2-[((R)-2'-hydroxytetradecanoyl) amino] tricosane (4) and (2S,3S,4R)-1,3,4-triacetoxy-2-[((R)-2'-acetoxyoctadecanoyl) amino]octadecane (5) along with africanene (1, reasonably good yield), 23-demethylgargosterol (2) and batylalcohol (3) have been isolated from the soft coral Sinularia leptoclados. Preliminary studies for pharmacological activity (blind screening and toxicity studies) of africanene were conducted. Africanene exhibited in vitro and in vivo cytotoxicity, dose dependent hypotensive activity as well as antiinflammatory activity. The pharmacological and toxicity studies on africanene are being reported for the first time and findings strongly encourage further investigation. Compounds 1, 4 and 5 were studied for the antibacterial, antifungal and antiviral activity while compounds 4 and 5 were also studied for the short term in vitro cytotoxic activity.
Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Antineoplásicos/isolamento & purificação , Cnidários/química , Esfingolipídeos/isolamento & purificação , Terpenos/isolamento & purificação , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/toxicidade , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Antineoplásicos/farmacologia , Antivirais/isolamento & purificação , Antivirais/farmacologia , Antivirais/toxicidade , Anuros , Bactérias/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Sobrevivência Celular , Cães , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Contração Muscular/efeitos dos fármacos , Ratos , Ratos Wistar , Esfingolipídeos/farmacologia , Esfingolipídeos/toxicidade , Terpenos/farmacologiaRESUMO
The interaction between the alpha subunit of G protein Gs (Gsalpha) and the two cytoplasmic domains of adenylyl cyclase (C1 and C2) is a key step in the stimulation of cAMP synthesis by hormones. Mutational analysis reveals that three discrete regions in the primary sequence of adenylyl cyclase affect the EC50 values for Gsalpha activation and thus are the affinity determinants of Gsalpha. Based on the three-dimensional structure of C2.forskolin dimer, these three regions (C2 alpha2, C2 alpha3/beta4, and C1 beta1) are close together and form a negatively charged and hydrophobic groove the width of an alpha helix that can accommodate the positively charged adenylyl cyclase binding region of Gsalpha. Two mutations in the C2 alpha3/beta4 region decrease the Vmax values of Gsalpha activation without an increase in the EC50 values. Since these three regions are distal to the catalytic site, the likely mechanism for Gsalpha activation is to modulate the structure of the active site by controlling the orientation of the C2 alpha2 and alpha3/beta4 structures.