Plasmodium knowlesi, a malaria parasite originally thought to be restricted to macaques in Southeast Asia, has recently been recognized as a significant cause of human malaria. Unlike the benign and morphologically similar P. malariae, these parasites can lead to fatal infections. Malaria parasites, including P. knowlesi, have not yet been detected in macaques of the Kapit Division of Malaysian Borneo, where the majority of human knowlesi malaria cases have been reported. In order to extend our understanding of the epidemiology and evolutionary history of P. knowlesi, we examined 108 wild macaques for malaria parasites and sequenced the circumsporozoite protein (csp) gene and mitochondrial (mt) DNA of P. knowlesi isolates derived from macaques and humans. We detected five species of Plasmodium (P. knowlesi, P. inui, P. cynomolgi, P. fieldi and P. coatneyi) in the long-tailed and pig-tailed macaques, and an extremely high prevalence of P. inui and P. knowlesi. Macaques had a higher number of P. knowlesi genotypes per infection than humans, and some diverse alleles of the P. knowlesi csp gene and certain mtDNA haplotypes were shared between both hosts. Analyses of DNA sequence data indicate that there are no mtDNA lineages associated exclusively with either host. Furthermore, our analyses of the mtDNA data reveal that P. knowlesi is derived from an ancestral parasite population that existed prior to human settlement in Southeast Asia, and underwent significant population expansion approximately 30,000-40,000 years ago. Our results indicate that human infections with P. knowlesi are not newly emergent in Southeast Asia and that knowlesi malaria is primarily a zoonosis with wild macaques as the reservoir hosts. However, ongoing ecological changes resulting from deforestation, with an associated increase in the human population, could enable this pathogenic species of Plasmodium to switch to humans as the preferred host. 相似文献
Interferon beta (IFNβ) is naturally occurring cytokine made and secreted by immune cells in response to stimuli. Non-glycosylated interferon beta Ser 相似文献
A small population of Mugger crocodiles occurs in the southeastern part of Iran, in Sistan & Baluchestan Province, at the westernmost global range of the species. The peak nesting season is May and consequently the eggs hatch in July, but the nesting season can be extended. In four nests found in the wild, 24, 26, 21 and 13 eggs were counted. A 2.2 m long female, which fell in an overflow pond, laid 21 eggs on a concrete surface exposed to the air. A female kept in captivity laid 18 and 25 eggs in two consecutive years. The mean size for the eggs in the last three nests was calculated as 75.7 x 47.7 mm and 91.27 g in weight. The mean total length and weight for 19 hatchlings was 30.47 cm (29.2–33.9 cm) and 84.3 g (66.2 to 90.3 g) respectively. Based on the number of observed hatchlings compared with the clutch size, it seems that hatchlings have a high mortality rate in the early stages after hatching as a result of natural threats. 相似文献
Accidents resulting in widespread dispersal of radioactive materials have given rise to a need for materials that are convenient in allowing individual dose assessment. The present study examines natural Dead Sea salt adopted as a model thermoluminescence dosimetry system. Samples were prepared in two different forms, loose-raw and loose-ground, subsequently exposed to 60Co gamma-rays, delivering doses in the range 2–10 Gy. Key thermoluminescence (TL) properties were examined, including glow curves, dose response, sensitivity, reproducibility and fading. Glow curves shapes were found to be independent of given dose, prominent TL peaks for the raw and ground samples appearing in the temperature ranges 361–385 ºC and 366–401 ºC, respectively. The deconvolution of glow curves has been undertaken using GlowFit, resulting in ten overlapping first-order kinetic glow peaks. For both sample forms, the integrated TL yield displays linearity of response with dose, the loose-raw salt showing some 2.5 × the sensitivity of the ground salt. The samples showed similar degrees of fading, with respective residual signals 28 days post-irradiation of 66% and 62% for the ground and raw forms respectively; conversely, confronted by light-induced fading the respective signal losses were 62% and 80%. The effective atomic number of the Dead Sea salt of 16.3 is comparable to that of TLD-200 (Zeff 16.3), suitable as an environmental radiation monitor in accident situations but requiring careful calibration in the reconstruction of soft tissue dose (soft tissue Zeff 7.2). Sample luminescence studies were carried out via Raman and Photoluminescence spectroscopy as well as X-ray diffraction, ionizing radiation dependent variation in lattice structure being found to influence TL response.
The AcmA binding domains of Lactococcus lactis were used to display the VP1 protein of chicken anemia virus (CAV) on Lactobacillus acidophilus. One and two repeats of the cell wall binding domain of acmA gene were amplified from L. lactis MG1363 genome and then inserted into co-expression vector, pBudCE4.1. The VP1 gene of CAV was then fused to the acmA sequences and the VP2 gene was cloned into the second MCS of the same vector before transformation into Escherichia coli. The expressed recombinant proteins were purified using a His-tag affinity column and mixed with a culture of L. acidophilus. Whole cell ELISA and immunofluorescence assay showed the binding of the recombinant VP1 protein on the surface of the bacterial
cells. The lactobacilli cells carrying the CAV VP1 protein were used to immunize specific pathogen-free chickens through the
oral route. A moderate level of neutralizing antibody to CAV was detected in the serum of the immunized chickens. A VP1-specific
proliferative response was observed in splenocytes of the chickens after oral immunization. The vaccinated groups also showed
increased levels of Th1 cytokines interleukin (IL)-2, IL-12, and IFN-γ. These observations suggest that L. acidophilus can be used in the delivery of vaccines to chickens. 相似文献
INTRODUCTION: Non-Hodgkin's lymphoma (NHL) is often complicated by pleural effusion and ascites. The present study is an attempt to categorize the lymphomatous effusions according to the WHO classification, using archival material. METHODS: May-Grünwald-Giemsa and Papanicolaou-stained smears of 31 lymphomatous effusion specimens were reviewed. Of these, detailed cytological assessment was done on 12 pleural effusions and ten ascitic fluid specimens from 22 patients using the WHO lymphoma classification system. Immunocytochemical studies were performed in 21 specimens. RESULTS: Based on cytomorphological features, the 22 lymphomatous effusion specimens were categorized into lymphoplasmacytoid lymphoma (1), follicle centre cell (FCC) grade-1 (centrocytic) lymphoma (3), FCC grade-2 (centrocytic-centroblastic) lymphoma (3), FCC grade-3 (centroblastic) lymphoma (4), large cell immunoblastic lymphoma (4), lymphoblastic lymphoma (2), anaplastic large cell lymphoma (3) and miscellaneous types (2). Immunocytochemically, the lymphoma cells were T-cell (positive for CD3) and B-cell type (CD20 positive) in five and six cases respectively. CONCLUSION: Cytological examination of pleural effusion and ascitic fluid samples, supported by immunocytochemical studies, may be useful for the classification of lymphomas under the WHO system. 相似文献
Over two hundred bacteria were isolated from the halosphere, rhizosphere and endophyte of Malaysian maize plantation and screened
for phytases activity. Thirty isolates with high detectable phytase activity were chosen for media optimization study and
species identification. Ten types of bacterial phytase producers have been discovered in this study, which provides opportunity
for characterization of new phytase(s) and various commercial and environmental applications. The majority of the bacterial
isolates with high detectable phytase activity were of endophyte origin and 1.6% of the total isolates showed phytase activity
of more than 1 U/ml. Most of the strains produced extra-cellular phytase and Staphylococcus lentus ASUIA 279 showed the highest phytase activity of 1.913 U/ml. All 30 species used in media optimization study exhibit favorable
enzyme production when 1% rice bran was included in the growth media. 相似文献
Aberrations of DNA methylation are early events in the development of tumors. In this study, we investigated the DNA methylation status of growth hormone secretagogue receptor (GHSR), a promising pan-cancer biomarker, in gastric cancer (GC). Initially, data sets from DNA methylation and gene expression studies available at Gene Expression Omnibus (GEO) were analyzed. Confirmation was done on primary tumor specimens and adjacent normal stomach tissue samples. Both analyses showed significant hypermethylation of GHSR. For further validation, The Cancer Genome Atlas data on stomach cancer was used. A receiver operating characteristic curve analysis yielded an area under the curve value of 0.85, corroborating its usefulness as a diagnostic marker. A genome-wide comethylation analysis revealed several correlated genes. CREB1 was found to act as an upstream regulator of this gene network. Furthermore, GHSR methylation was found to be a biomarker in several other tumor entities, namely cancers of the bladder, endometrium, esophagus, head and neck, liver, thyroid, kidney, and ovary. Our findings along with previous reports on other types of cancer suggest a high potential of GHSR gene methylation as a pan-cancer biomarker, which could be considered for liquid biopsy applications. 相似文献
Low-income countries with high Tuberculosis burden have few reference laboratories able to perform TB culture. In 2006, the Zanzibar National TB Control Programme planned to decentralize TB diagnostics. The Italian Cooperation Agency with the scientific support of the "L. Spallanzani" National Institute for Infectious Diseases sustained the project through the implementation of a TB reference laboratory in a low-income country with a high prevalence of TB. The implementation steps were: 1) TB laboratory design according to the WHO standards; 2) laboratory equipment and reagent supplies for microscopy, cultures, and identification; 3) on-the-job training of the local staff; 4) web- and telemedicine-based supervision.From April 2007 to December 2010, 921 sputum samples were received from 40 peripheral laboratories: 120 TB cases were diagnosed. Of all the smear-positive cases, 74.2% were culture-positive. During the year 2010, the smear positive to culture positive rate increased up to 100%.In March 20, 2010 the Ministry of Health and Social Welfare of Zanzibar officially recognized the Public Health Laboratory- Ivo de Carneri as the National TB Reference Laboratory for the Zanzibar Archipelago.An advanced TB laboratory can represent a low cost solution to strengthen the TB diagnosis, to provide capacity building and mid-term sustainability. 相似文献