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1.
Vaccine ; 42(9): 2290-2298, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431444

RESUMO

BACKGROUND: World Health Organization human papillomavirus (HPV) vaccination recommendations include a single- or two-dose schedule in individuals 9-20 years old and advice for generating data on single-dose efficacy or immunobridging. The ongoing Phase 3 trial of Innovax's bivalent (types 16 and 18) HPV vaccine (Cecolin®) assesses in low- and middle-income countries alternative dosing schedules and generates data following one dose in girls 9-14 years old. Interim data for the 6-month dosing groups are presented. METHODS: In Bangladesh and Ghana, 1,025 girls were randomized to receive either two doses of Cecolin at 6-, 12-, or 24-month intervals; one dose of Gardasil® followed by one dose of Cecolin at month 24; or two doses of Gardasil 6 months apart (referent). Serology was measured by enzyme-linked immunosorbent assay (ELISA) and, in a subset, by neutralization assays. Primary objectives include immunological non-inferiority of the Cecolin schedules to referent one month after the second dose. Safety endpoints include reactogenicity and unsolicited adverse events for 7 and 30 days post-vaccination, respectively, as well as serious adverse events throughout the study. RESULTS: Interim analyses included data from the two groups on a 0, 6-month schedule with 205 participants per group. One month after Dose 2, 100% of participants were seropositive by ELISA and had seroconverted for both antigens. Non-inferiority of Cecolin to Gardasil was demonstrated. Six months following one dose, over 96% of participants were seropositive by ELISA for both HPV antigens, with a trend for higher geometric mean concentration following Cecolin administration. Reactogenicity and safety were comparable between both vaccines. CONCLUSIONS: Cecolin in a 0, 6-month schedule elicits robust immunogenicity. Non-inferiority to Gardasil was demonstrated one month after a 0, 6-month schedule. Immunogenicity following one dose was comparable to Gardasil up to six months. Both vaccines were safe and well tolerated (ClinicalTrials.gov No. 04508309).


Assuntos
Infecções por Papillomavirus , Vacinas contra Papillomavirus , Feminino , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/efeitos adversos , Infecções por Papillomavirus/prevenção & controle , Anticorpos Antivirais , Vacinação , Imunogenicidade da Vacina
2.
Diabetol Metab Syndr ; 14(1): 148, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229864

RESUMO

BACKGROUND: Diabetes-induced liver injury is a complication of diabetes mellitus of which there are no approved drugs for effective treatment or prevention. This study investigates possible hepatoprotective effect of alpha-lipoic acid (ALA), and sulfane sulfur/hydrogen sulfide pathway as a novel protective mechanism in a rat model of type 2 diabetes-induced liver injury. METHODS: Thirty Sprague-Dawley rats underwent fasting for 12 h after which fasting blood glucose was measured and rats were randomly assigned to diabetic and non-diabetic groups. Type 2 diabetes mellitus (T2DM) was induced in diabetic group by administration of nicotinamide (110 mg/kg) and streptozotocin (55 mg/kg). Diabetic rats were treated daily with ALA (60 mg/kg/day p.o.) or 40 mg/kg/day DL-propargylglycine (PPG, an inhibitor of endogenous hydrogen sulfide production) for 6 weeks and then sacrificed. Liver, pancreas and blood samples were collected for analysis. Untreated T2DM rats received distilled water. RESULTS: Hypoinsulinemia, hyperglycemia, hepatomegaly and reduced hepatic glycogen content were observed in untreated T2DM rats compared to healthy control group (p < 0.001). Also, the pancreas of untreated T2DM rats showed severely damaged pancreatic islets while liver damage was characterized by markedly increased hepatocellular vacuolation, sinusoidal enlargement, abnormal intrahepatic lipid accumulation, severe transaminitis, hyperbilirubinemia, and impaired hepatic antioxidant status and inflammation compared to healthy control rats (p < 0.01). While pharmacological inhibition of hepatic sulfane sulfur/hydrogen sulfide with PPG administration aggravated these pathological changes (p < 0.05), ALA strongly prevented these changes. ALA also significantly increased hepatic expression of hydrogen sulfide-producing enzymes (cystathionine γ-lyase and 3-mecaptopyruvate sulfurtransferase) as well as hepatic sulfane sulfur and hydrogen sulfide levels compared to all groups (p < 0.01). CONCLUSIONS: To the best of our knowledge, this is the first experimental evidence showing that ALA prevents diabetes-induced liver injury by activating hepatic sulfane sulfur/hydrogen sulfide pathway via upregulation of hepatic cystathionine γ-lyase and 3-mecaptopyruvate sulfurtransferase expressions. Therefore, ALA could serve as a novel pharmacological agent for the treatment and prevention of diabetes-induced liver injury, with hepatic sulfane sulfur/hydrogen sulfide as a novel therapeutic target.

3.
Front Pharmacol ; 13: 1077380, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618915

RESUMO

Background: Plant as a source of medicine has gained international popularity in recent times because of its natural origin, availability in local communities, cheaper to purchase, ease of administration, and its usefulness as an alternative treatment in case of numerous side effects and drug resistance. However, the use of herbal formulations can also result in short-term and long-term organ damage or dysfunction to the host. In this study, chloroform fractions of the leaves of two medicinal plants, Alchornea cordifolia (ACL) and Carapa procera (CPL), were investigated for their toxicological and anti-malarial effects in murine models. Method: Acute (14-day) and sub-acute (28-day) studies were conducted based on the Organization for Economic Cooperation and Development (OECD) Guidelines in Institute for Cancer Research (ICR) mice and Sprague Dawley (SD) rats respectively. A dosage of 2000 mg/kg body weight was administered orally to each ICR mouse during the acute study and 100, 300, and 1000 mg/kg body weight to each SD rat during the sub-acute study. A 5-day curative anti-plasmodial activity was assessed in ICR mouse model. Results: The assessment of toxicity revealed that all three fractions did not influence mortality, clinical appearance, body weight gain, or necropsy at the various doses. Hematological and serum biochemical analysis indicated no significant elevations in liver and renal function parameters. Histopathological examinations of the liver indicated reversible liver degeneration with the chloroform fraction of the 100% ethanol extract of Carapa procera leaves (CPL100%) at 1000 mg/kg. Anti-plasmodial assessments showed CPL100% exhibiting dose-dependent anti-plasmodial activity from 16% to 26.67%. On the other hand, chloroform fraction of the 100% ethanol extract of Alchornea cordifolia leaves (ACL100%) showed declining anti-plasmodial activity from 21.1% to 15.1%. Conclusion: These preliminary findings demonstrate that chloroform fractions of the leaves of Carapa procera and Alchornea cordifolia may be safe agents for treating malaria hence further development for drug discovery must be pursued.

4.
BMC Complement Altern Med ; 17(1): 152, 2017 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-28284204

RESUMO

BACKGROUND: Calcium (Ca)- magnesium (Mg) imbalance is implicated in prostate cancer. Ca/Mg ratio increases or decreases with proliferation or apoptosis, respectively. The study examined whether this Ca/Mg imbalance exists in BPH patients and the effect of a phytotherapeutic drug on the Ca/Mg ratio. METHODS: Thirty (30) BPH patients who used the ethanolic root extract of Croton membranaceus (60 mg/day) for 3 months were examined for serum Ca, Mg, phosphate, parathyroid hormone (PTH), vitamin D, prostate specific antigen (PSA) levels and renal function tests (RFT) before (BT) and after treatment (AT) alongside thirty (30) controls. Twenty (20) trace element including Mg and Ca were determined in the drug by neutron activation analysis (NAA). RESULTS: RFT, PTH and vitamin D for BT, AT and controls (C) were normal. Mean PSA was 1.0 ± 0.64 (C), 27.9 ± 19.0 (BT) and 16.2 ± 11.8 ng/mL (AT) (p = 0.002). Mg, Ca/Mg ratio BT, AT and control were significantly different (p = 0.0001, respectively). After treatment, Mg and Ca/Mg ratio were not different from controls. The prevalence of Ca/Mg imbalance was 80% (BT), 13.3% (AT) and 3.3% (control group). CONCLUSION: Ca/Mg ratio imbalance is associated with BPH. This has previously not been demonstrated. The imbalance was significantly corrected after treatment with the phytotherapeutic drug.


Assuntos
Cálcio/sangue , Croton/química , Magnésio/sangue , Extratos Vegetais/uso terapêutico , Hiperplasia Prostática/sangue , Hiperplasia Prostática/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Raízes de Plantas/química , Prevalência , Próstata/patologia , Estudos Retrospectivos
5.
Artigo em Inglês | MEDLINE | ID: mdl-26106434

RESUMO

Benign prostatic hyperplasia (BPH) is an enlargement of the prostate. The study aimed at validating the use of freeze-dried Croton membranaceus ethanolic root extract for BPH management. Thirty-three patients were observed before and after 3-month administration of 20 mg t.i.d orally. The International Prostate Symptom Score (IPSS), and the International Index of Erectile Function (IIEF) questionnaires were used. Total/free PSA (tPSA, fPSA), renal, liver function, lipid tests, and ultrasonographic imaging were performed. Thirty (30) patients (66 ± 11 years) completed the study. IPSS results showed 37% had severe, 40% moderate, and 23% mild symptoms before; 57% and 43% had moderate and mild symptoms, respectively, after treatment. IIED of patients' results showed 30% with severe, 40% moderate, 24% mild-moderate, 3% mild, and 3% no erectile dysfunction before treatment and 20% severe, 43% moderate, and 37% mild-moderate dysfunction, after treatment. Quality of life (QoL) improved (P = 0.001). Significant but non-pathological increases in total and indirect bilirubin as well as apolipoprotein A occurred. Mean tPSA reduced from 27.9 ± 19.0 to 16.2 ± 11.8 ng/mL (P = 0.002); fPSA from 6.1 ± 4.8 to 3.9 ± 2.9 ng/mL (P = 0.045); and prostate volume from 101.8 ± 41.3 to 54.5 ± 24.8 cm(3) (P = 0.023). C. membranaceus shrinks the prostate and improves QoL.

6.
J Ethnopharmacol ; 157: 90-8, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25256687

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Croton membranaceus leaf extracts are used in the Bahamas to aromatize tobacco. In Nigeria it is used to improve digestion and in Ghana, the root extract is used for the treatment of benign prostatic hyperplasia (BPH). Despite claims of efficacy no data exists to support this. The aim of this study was to determine if Croton membranaceus aqueous root extract (CMARE) could attenuate the development of BPH in an animal model. MATERIALS AND METHODS: Fifty (50) adult male Sprague-Dawley rats weighing 200-250g were randomly divided into 5 groups. Group 1 served as the control and received normal saline p.o. Groups 2-5 were castrated and injected with 5mg/kg b.wt. testosterone propionate subcutaneously for 28 days. Group 2 (model group) had no further treatment. Group 3 was simultaneously given 0.5mg/kg b.wt. finasteride p.o. throughout. Groups 4 and 5 received 30mg/kg b.wt. [low dose (LD)] and 300mg/kg b.wt. [high dose (HD)] CMARE, respectively, for 28 days. Rats were sacrificed at the end of the study and all prostate organs harvested. Wet weights, volumes and prostatic index (PI) were determined. Tissues were histologically examined. Serum prostate specific antigen (PSA) and dihydrotestosterone (DHT) levels were determined. RESULTS: Prostate volume of the control group was 0.67±0.23cm(3). The model, finasteride, CMARE LD and HD groups had the following volumes: 0.92±0.12, 0.84±0.16, 0.79±0.16 and 0.80±0.19cm(3), respectively. Only the model group showed significant statistical differences with the control (p=0.007). PI for control, model, finasteride, LD and HD groups was as follows: 0.19±0.04, 0.30±0.04, 0.25±0.04, 0.21±0.05 and 0.22±0.05. No statistical differences between the control PI and the CMARE treated groups were observed. Histologically, the model group had massive growth of columnar stromal and epithelial cells. CMARE and finasteride attenuated this growth with a resultant thin layer of stromal and epithelial cells similar to the control. PSA levels were significantly lower in the treatment groups. CONCLUSION: CMARE reduces stromal and epithelial cell growth, and subsequently shrinks enlarged prostate. This is the first scientific proof validating the anecdotal evidence of CMARE efficacy in the management of BPH.


Assuntos
Croton/química , Extratos Vegetais/farmacologia , Hiperplasia Prostática/tratamento farmacológico , Animais , Di-Hidrotestosterona/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Finasterida/farmacologia , Masculino , Medicina Tradicional , Extratos Vegetais/administração & dosagem , Raízes de Plantas , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/patologia , Ratos , Ratos Sprague-Dawley
7.
Pharm Biol ; 51(6): 691-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23570525

RESUMO

CONTEXT: Phyllanthus niruri L. (Euphorbiaceae), a medicinal plant traditionally known for dissolving kidney stones, is used prophylactically as an antimalarial agent. OBJECTIVE: The study was undertaken to determine its effect on some male hormones and other toxicological properties due to paucity of its data despite its wide use. MATERIAL AND METHODS: Male Sprague-Dawley rats (100-140 g) were used. Group 1 [control group (C), n = 6] received water. Group 2 [low-dose test group (LD), n = 6] received 50 mg/kg body weight (b.wt.) aqueous leaf extract orally. Group 3 [high-dose test group (HD), n = 6] received 500 mg/kg b.wt. extract for 90 days. Upon sacrifice, among other organs the testes were harvested. Blood samples drawn were used for biochemical (including progesterone, estrogen and testosterone), cytotoxicity and hematological assays. RESULTS: C, LD and HD estrogen values were 192 ± 25, 385 ± 122 and 962 ± 357 pg/ml, respectively. In the same order, progesterone values were 96 ± 24, 155 ± 45 and 320 ± 80 pg/ml, respectively. Testosterone levels were 5210 ± 1090, 4710 ± 220 and 4500 ± 580 pg/ml, respectively. Significant differences were observed in the estrogen and progesterone levels (p = 0.001). Degenerative changes were observed histologically. Cytotoxicity at 50% (CC50) was 10.0 µg/ml. DISCUSSION AND CONCLUSION: This antimalarial plant is mildly cytotoxic with male antifertility properties.


Assuntos
Antimaláricos/toxicidade , Phyllanthus/química , Extratos Vegetais/toxicidade , Animais , Antimaláricos/administração & dosagem , Antimaláricos/isolamento & purificação , Relação Dose-Resposta a Droga , Estrogênios/sangue , Masculino , Medicina Tradicional , Extratos Vegetais/administração & dosagem , Folhas de Planta , Progesterona/sangue , Ratos , Ratos Sprague-Dawley , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/sangue
8.
J Virol Methods ; 185(2): 244-53, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22796283

RESUMO

Microarrays are suitable for multiplexed detection and typing of pathogens. Avian influenza virus (AIV) is currently classified into 16 H (hemagglutinin) and 9 N (neuraminidase) subtypes, whereas Newcastle disease virus (NDV) strains differ in virulence and are broadly classified into high and low pathogenicity types. In this study, three assays for detection and typing of poultry viruses were developed on an automated microarray platform: a multiplex assay for simultaneous detection of AIV and detection and pathotyping of NDV, and two separate assays for differentiating all AIV H and N subtypes. The AIV-NDV multiplex assay detected all strains in a 63 virus panel, and accurately typed all high pathogenicity NDV strains tested. A limit of detection of 10(1)-10(3) TCID(50)/mL and 200-400 EID(50)/mL was obtained for NDV and AIV, respectively. The AIV typing assays accurately typed all 41 AIV strains and a limit of detection of 4-200 EID(50)/mL was obtained. Assay validation showed that the microarray assays were generally comparable to real-time RT-PCR. However, the AIV typing microarray assays detected more positive clinical samples than the AIV matrix real-time RT-PCR, and also provided information regarding the subtype. The AIV-NDV multiplex and AIV H typing microarray assays detected mixed infections and could be useful for detection and typing of AIV and NDV.


Assuntos
Vírus da Influenza A/isolamento & purificação , Influenza Aviária/diagnóstico , Doença de Newcastle/diagnóstico , Vírus da Doença de Newcastle/isolamento & purificação , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Animais , Galinhas/virologia , Genes Virais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/análise , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Aviária/virologia , Neuraminidase/análise , Neuraminidase/genética , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Sensibilidade e Especificidade , Perus/virologia , Proteínas Virais de Fusão/análise , Proteínas Virais de Fusão/genética
9.
J Ethnopharmacol ; 139(1): 265-72, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22101359

RESUMO

Moringa oleifera Lam. (order -Moringales, family -Moringaceae and genus -Moringa) is a well known nutraceutical used in the treatment of hypercholesterolemia and hyperglycemia, and also, as a nutritional supplementation. Its popularity use raises the question of possible toxicity at supra-supplementation levels. The objective of the study was to ascertain possible acute toxicity with supra-supplementation using Sprague-Dawley (S-D) rats. In experiment 1, human peripheral blood mononuclear cells were given graded doses of Moringa oleifera aqueous leaf extract to induce cytotoxicity. In experiment 2, two groups of rats received low and high dose (LD and HD, respectively) levels (1,000 and 3,000 mg/kgb.wt, respectively) per o.s. alongside negative and positive control rats (0.9% saline and 10mg/mL N-ethyl-N-nitrosourea - administered i.m., respectively). Each group consisted of five rats. Rats were killed after 48 h and the femur bone marrow aspirate examined for polychromatic micronucleated erythrocytes (PCEMN)/normochromatic micronucleated erythrocytes (NCEMN) ratios after Giemsa/Leishman staining. In experiment 3, control, LD and HD groups were established. The LD and HD extracts were administered per o.s. to the respective groups and observed for 14 days. Each group consisted of five rats. Blood was sampled after 48 h and 14 days and examined biochemically and haematologically for acute toxicity. Experiment 1 showed that Moringa oleifera was cytotoxic at 20mg/mL. In experiment 2, PCEMN/NCEMN ratios were: negative control=2.087; LD=1.849; HD=1.397; positive control=1.257. Statistically, LD and HD ratios were significant (p=0.020). Experiment 3 showed that hepatonephro-toxicity was nil with no abnormal haematology results. Genotoxicity results have hitherto not been shown. Moringa oleifera is genotoxic at supra-supplementation levels of 3,000 mg/kg b.wt. However, intake is safe at levels ≤ 1,000 mg/kg b.wt.


Assuntos
Suplementos Nutricionais/toxicidade , Moringa oleifera , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Animais , Medula Óssea/efeitos dos fármacos , Cloretos/sangue , Relação Dose-Resposta a Droga , Testes Hematológicos , L-Lactato Desidrogenase/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Testes para Micronúcleos , Folhas de Planta , Ratos , Ratos Sprague-Dawley , Albumina Sérica/análise , Sódio/sangue , Testes de Toxicidade Aguda , Ureia/sangue
10.
J Ethnopharmacol ; 134(3): 938-43, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21335084

RESUMO

AIM OF THE STUDY: Croton membranaceus root and leaf extracts are used in the Bahamas to aromatize tobacco, in Nigeria to improve digestion, and in Ghana, for benign prostate hyperplasia. Despite claims of success there is paucity of information on its toxicity. The aim of this study was to determine if Croton membranaceus has acute toxicity properties. MATERIALS AND METHODS: Roots were air-dried in a solar dryer for one week before milling. The powder was extracted with 96% ethanol, freeze-dried and re-extracted with distilled water and freeze-dried. 15 male Sprague-Dawley rats (180-200 g) were divided equally into 2 treatment groups [low dose (LD) and high dose (HD)], plus a control group (C). LD and HD received 1500 and 3000 mg/kg b.wt. Croton membranaceus aqueous extract, respectively, one time and observed for 14 days. Haematological [Full Blood Count and haemoglobin (Hb)], biochemical [bilirubin, alanine aminotransferase (ALA), aspartate aminotransferase (AST), total protein, albumin, globulin, alkaline phosphatise (ALP), γ-glutamyltranspetidase (GGT), urea, creatinine, creatinine kinase - Muscle and Brain (CK-MB), creatinine kinase - Total (CK-R)] examinations were performed. RESULTS: Control group's CK-MB (5444±534 U/L) and LD group CK-MB (4014±1016 U/L) were significantly different (p<0.05). Control and the HD group CK-MB (3955±1135 U/L) were significantly different (p<0.05). Both LD and HD CK-R levels (697±197U/L and 732±203 U/L, respectively), were lower than the control (1139±220 U/L) at 48 h and 14 days (p<0.05, p<0.05, respectively). γ-GT levels of the HD group was 4.8±0.4 U/L compared to the Control group value of 0.9±0.2 U/L (p<0.05). CONCLUSIONS: Taking all factors into consideration, Croton membranaceus ingestion does not produce general acute toxicity. However, its creatinine kinase lowering ability could be explored.


Assuntos
Croton/química , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Animais , Contagem de Células Sanguíneas , Testes de Química Clínica , Masculino , Ratos , Ratos Sprague-Dawley
11.
J Infect Dis ; 203(4): 556-60, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21248056

RESUMO

Recently, the World Health Organization emphasized the potential benefit of intermittent preventive treatment in infants (IPTi) to control malaria and officially recommended implementation of IPTi with sulfadoxine-pyrimethamine (SP) in areas with moderate and high transmission, where SP resistance is not high. As reported rebound effects make further observation mandatory, we performed a survey of participants of a former IPTi trial. Malariometric parameters were similar in the SP and the placebo group. In contrast, anti-Plasmodium falciparum lysate immunoglobulin G antibody levels, a proxy measure for preceding malaria episodes, remained lower in the SP arm. The most likely explanation is a lower overall exposure to parasitic antigens after IPTi.


Assuntos
Antimaláricos/uso terapêutico , Quimioprevenção/métodos , Malária Falciparum/epidemiologia , Malária Falciparum/prevenção & controle , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico , Anticorpos Antiprotozoários/sangue , Pré-Escolar , Combinação de Medicamentos , Feminino , Seguimentos , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Plasmodium falciparum/imunologia , Estudos Soroepidemiológicos
12.
Appl Environ Microbiol ; 73(14): 4609-18, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17513586

RESUMO

Association patterns between archaea and rumen protozoa were evaluated by analyzing archaeal 16S rRNA gene clone libraries from ovine rumen inoculated with different protozoa. Five protozoan inoculation treatments, fauna free (negative control), holotrich and cellulolytic protozoa, Isotricha and Dasytricha spp., Entodinium spp., and total fauna (type A) were tested. We used denaturing gradient gel electrophoresis, quantitative PCR, and phylogenetic analysis to evaluate the impact of the protozoan inoculants on the respective archaeal communities. Protozoan 18S ribosomal DNA clone libraries were also evaluated to monitor the protozoal population that was established by the inoculation. Phylogenetic analysis suggested that archaeal clones associated with the fauna-free, the Entodinium, and the type A inoculations clustered primarily with uncultured phylotypes. Polyplastron multivesiculatum was the predominant protozoan strain established by the holotrich and cellulolytic protozoan treatment, and this resulted predominantly in archaeal clones affiliated with uncultured and cultured methanogenic phylotypes (Methanosphaera stadtmanae, Methanobrevibacter ruminantium, and Methanobacterium bryantii). Furthermore, the Isotricha and Dasytricha inoculation treatment resulted primarily in archaeal clones affiliated with Methanobrevibacter smithii. This report provides the first assessment of the influence of protozoa on archaea within the rumen microbial community and provides evidence to suggest that different archaeal phylotypes associate with specific groups of protozoa. The observed patterns may be linked to the evolution of commensal and symbiotic relationships between archaea and protozoa in the ovine rumen environment. This report further underscores the prevalence and potential importance of a rather large group of uncultivated archaea in the ovine rumen, probably unrelated to known methanogens and undocumented in the bovine rumen.


Assuntos
Archaea/classificação , Archaea/isolamento & purificação , Eucariotos/crescimento & desenvolvimento , Rúmen/microbiologia , Rúmen/parasitologia , Animais , Archaea/genética , Biodiversidade , Impressões Digitais de DNA , DNA Arqueal/química , DNA Arqueal/genética , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Eletroforese em Gel de Poliacrilamida , Dados de Sequência Molecular , Desnaturação de Ácido Nucleico , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Homologia de Sequência , Ovinos
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