705 research outputs found
Pediatric carcinoma of rectum - Varanasi experience
Background : Primary gastrointestinal system malignancies constitute
approximately 2% of pediatric neoplasm and of these; colorectal
carcinoma is the second most common malignancy. This is one of the
rarer diseases in children. Aim : We reviewed our records to study the
clinical features, outcome and the follow-up of this condition with
evaluation of the prognostic factors. Settings and Design: Tertiary
care Pediatric Surgery centre. Retrospective study. Materials and
Methods : The data of all patients with diagnosis of colorectal
carcinoma from January 1986 to January 2006 were reviewed. The
confirmation of the diagnosis was by biopsy from the lesion. The age,
sex, family history, clinical features, response to the treatment and
follow-up were studied. Results : There were four male patients. All
had bleeding per rectum as the presenting complaint. Three patients had
advanced disease at presentation. All the patients had signet cell
adenocarcinoma. The two patients expired and one was lost to follow-up.
One patient is alive after one year of follow up and is receiving
treatment. Conclusion : Colorectal cancer in children though rare can
be a reality, hence any children presenting with pain in abdomen along
with doubtful history of constipation and rectal bleeding should be
examined carefully with special emphasis on digital rectal examination
Case Report: A Case of Wood-Smoke–Related Pulmonary Disease
CONTEXT: Biomass serves as a major fuel source for > 50% of the world’s population. The global burden of disease attributed to indoor air pollution from biomass combustion accounts for approximately 3% of worldwide disability-adjusted life-years lost. This is due to pneumonia in children and chronic obstructive pulmonary disease and lung cancer in women. CASE PRESENTATION: A 53-year-old man from Mexico was referred to the pulmonary clinic for evaluation of chronic productive cough and pulmonary nodules. In his youth, he worked at a charcoal plant in Mexico, where he burned wood and was exposed to massive amounts of smoke. His evaluation revealed thickened bronchovascular bundles with nodules on thoracic computed tomography, dark black plaques in large airways on bronchoscopy, and carbon-laden macrophages and fibrotic scars on lung biopsy. DISCUSSION: The patient was diagnosed with “hut lung,” a term that refers to the noninfectious, nonmalignant respiratory manifestations of chronic, high-level exposures to biomass smoke. This is the first reported case of hut lung associated with charcoal production. This case highlights that histopathologic abnormalities of the lung parenchyma may be present in patients with only mild symptoms and that clinical progression is likely a function of both the duration and intensity of exposure. RELEVANCE TO CLINICAL PRACTICE: As residents of lesser developed countries continue to be exposed to high levels of biomass smoke at work or at home and continue to immigrate to developed countries, it is important that health care providers in developed countries be aware of biomass-smoke–related pulmonary disease
Pediatric carcinoma of rectum - Varanasi experience
Background : Primary gastrointestinal system malignancies constitute
approximately 2% of pediatric neoplasm and of these; colorectal
carcinoma is the second most common malignancy. This is one of the
rarer diseases in children. Aim : We reviewed our records to study the
clinical features, outcome and the follow-up of this condition with
evaluation of the prognostic factors. Settings and Design: Tertiary
care Pediatric Surgery centre. Retrospective study. Materials and
Methods : The data of all patients with diagnosis of colorectal
carcinoma from January 1986 to January 2006 were reviewed. The
confirmation of the diagnosis was by biopsy from the lesion. The age,
sex, family history, clinical features, response to the treatment and
follow-up were studied. Results : There were four male patients. All
had bleeding per rectum as the presenting complaint. Three patients had
advanced disease at presentation. All the patients had signet cell
adenocarcinoma. The two patients expired and one was lost to follow-up.
One patient is alive after one year of follow up and is receiving
treatment. Conclusion : Colorectal cancer in children though rare can
be a reality, hence any children presenting with pain in abdomen along
with doubtful history of constipation and rectal bleeding should be
examined carefully with special emphasis on digital rectal examination
Distances and ages of globular clusters using Hipparcos parallaxes of local subdwarfs
We discuss the impact of Population II and Globular Cluster (GCs) stars on
the derivation of the age of the Universe, and on the study of the formation
and early evolution of galaxies, our own in particular. The long-standing
problem of the actual distance scale to Population II stars and GCs is
addressed, and a variety of different methods commonly used to derive distances
to Population II stars are briefly reviewed. Emphasis is given to the
discussion of distances and ages for GCs derived using Hipparcos parallaxes of
local subdwarfs. Results obtained by different authors are slightly different,
depending on different assumptions about metallicity scale, reddenings, and
corrections for undetected binaries. These and other uncertainties present in
the method are discussed. Finally, we outline progress expected in the near
future.Comment: Invited review article to appear in: `Post-Hipparcos Cosmic Candles',
A. Heck & F. Caputo (Eds), Kluwer Academic Publ., Dordrecht, in press. 22
pages including 3 tables and 2 postscript figures, uses Kluwer's crckapb.sty
LaTeX style file, enclose
Observation of epitaxially ordered twinned zinc aluminate “nanoblades” on c-capphire
We report the observation of a novel nanostructured growth mode of the ceramic spinel zinc aluminate grown on c-sapphire in the form of epitaxially ordered twinned crystallites with pronounced vertically aligned “nanoblades” on top of these crystallites. The nanostructures are formed on bare c-sapphire substrates using a vapour phase transport method. Electron microscopy images reveal the nanostructure morphology and dimensions and allow direct and indirect observation of the twin boundary location in a number of samples. The nanoblade structure with sharply rising sidewalls gives rise to a distinctive bright contrast in secondary electron images in scanning electron microscopy measurements
Daidzein Prevents the Increase in CD4+CD28null T Cells and B Lymphopoesis in Ovariectomized Mice: A Key Mechanism for Anti-Osteoclastogenic Effect
Estrogen deficiency leads to an upregulation of TNF-α producing T cells and B-lymphopoesis which augments osteoclastogenesis. Estrogen deficiency also increases the population of premature senescent CD4+CD28null T cells which secrete a higher amount of TNF-α thus leading to enhanced osteoclastogenesis. Isoflavonoids like daidzein and genistein are found mostly in soybeans, legumes, and peas. These share structural similarity with 17β-stradiol (E2) and have osteoprotective role. This study explores the effect of daidzein (Daid) on the proliferation of TNF-α producing T cells, premature senescent T cells and B cell lymphopoesis under estrogen deficient conditions. For this study adult Balb/c mice were treated with Daid at 10 mg/kg body weight dose by oral gavage daily post ovariectomy (Ovx). After six weeks animals were autopsied and bone marrow and spleen cells were collected for FACS analysis. Blood serum was collected for ELISA. It was observed that Ovx mice treated with Daid for six weeks show reduction in Ovx induced expansion of CD4+ T cells in bone marrow and spleen when analysed by flow cytometry. Estrogen deficiency led to increased prevalence of TNF-α secreting CD4+CD28null T cells, however, treatment with Daid increased the percentage of CD4+CD28+ T cells. Co-culture of CD4+CD28null T cells and bone marrow resulted in enhanced osteoclastogenesis as evident by increased tartarate resistant acid phosphatase (TRAP) expression, an osteoclast marker. However, treatment with Daid resulted in reduced osteoclastogenesis in CD4+CD28null T cells and bone marrow cell co-culture. Daid also regulated B lymphopoesis and decreased mRNA levels of RANKL in B220+ cells. Taken together, we propose that one of the mechanisms by which Daid prevents bone loss is by reversing the detrimental immune changes as a result of estrogen deficiency
Agronomic Management of Indigenous Mycorrhizas
Many of the advantages conferred to plants by arbuscular mycorrhiza (AM) are associated to the ability of AM plants to explore a greater volume of soil through the extraradical mycelium. Sieverding (1991) estimates that for each centimetre of colonized root there is an increase of 15 cm3 on the volume of soil explored, this value can increase to 200 cm3 depending on the circumstances. Due to the enhancement of the volume of soil explored and the ability of the extraradical mycelium to absorb and translocate nutrients to the plant, one of the most obvious and important advantages resulting from mycorrhization is the uptake of nutrients. Among of which the ones that have immobilized forms in soil, such as P, assume particular significance. Besides this, many other benefits are recognized for AM plants (Gupta et al, 2000): water stress alleviation (Augé, 2004; Cho et al, 2006), protection from root pathogens (Graham, 2001), tolerance to toxic heavy metals and phytoremediation (Audet and Charest, 2006; Göhre and Paszkowski, 2006), tolerance to adverse conditions such as very high or low temperature, high salinity (Sannazzaro et al, 2006), high or low pH (Yano and Takaki, 2005) or better performance during transplantation shock (Subhan et al, 1998). The extraradical hyphae also stabilize soil aggregates by both enmeshing soil particles (Miller e Jastrow, 1992) and producing a glycoprotein, golmalin, which may act as a glue-like substance to adhere soil particles together (Wright and Upadhyaya, 1998).
Despite the ubiquous distribution of mycorrhizal fungi (Smith and Read, 2000) and only a relative specificity between host plants and fungal isolates (McGonigle and Fitter, 1990), the obligate nature of the symbiosis implies the establishment of a plant propagation system, either under greenhouse conditions or in vitro laboratory propagation. These techniques result in high inoculum production costs, which still remains a serious problem since they are not competitive with production costs of phosphorus fertilizer. Even if farmers understand the significance of sustainable agricultural systems, the reduction of phosphorus inputs by using AM fungal inocula alone cannot be justified except, perhaps, in the case of high value crops (Saioto and Marumoto, 2002). Nurseries, high income horticulture farmers and no-agricultural application such as rehabilitation of degraded or devegetated landscapes are examples of areas where the use of commercial inoculum is current. Another serious problem is quality of commercial available products concerning guarantee of phatogene free content, storage conditions, most effective application methods and what types to use. Besides the information provided by suppliers about its inoculum can be deceiving, as from the usually referred total counts, only a fraction may be effective for a particular plant or in specific soil conditions. Gianinazzi and Vosátka (2004) assume that progress should be made towards registration procedures that stimulate the development of the mycorrhizal industry.
Some on-farm inoculum production and application methods have been studied, allowing farmers to produce locally adapted isolates and generate a taxonomically diverse inoculum (Mohandas et al, 2004; Douds et al, 2005). However the inocula produced this way are not readily processed for mechanical application to the fields, being an obstacle to the utilization in large scale agriculture, especially row crops, moreover it would represent an additional mechanical operation with the corresponding economic and soil compaction costs.
It is well recognized that inoculation of AM fungi has a potential significance in not only sustainable crop production, but also environmental conservation. However, the status quo of inoculation is far from practical technology that can be widely used in the field. Together a further basic understanding of the biology and diversity of AM fungi is needed (Abbott at al, 1995; Saito and Marumoto, 2002).
Advances in ecology during the past decade have led to a much more detailed understanding of the potential negative consequences of species introductions and the potential for negative ecological consequences of invasions by mycorrhizal fungi is poorly understood. Schwartz et al, (2006) recommend that a careful assessment documenting the need for inoculation, and the likelihood of success, should be conducted prior to inoculation because inoculations are not universally beneficial.
Agricultural practices such as crop rotation, tillage, weed control and fertilizer apllication all produce changes in the chemical, physical and biological soil variables and affect the ecological niches available for occupancy by the soil biota, influencing in different ways the symbiosis performance and consequently the inoculum development, shaping changes and upset balance of native populations. The molecular biology tools developed in the latest years have been very important for our perception of these changes, ensuing awareness of management choice implications in AM development.
In this context, for extensive farming systems and regarding environmental and economic costs, the identification of agronomic management practices that allow controlled manipulation of the fungal community and capitalization of AM mutualistic effect making use of local inoculum, seem to be a wise option for mycorrhiza promotion and development of sustainable crop production
Choroidal melanoma metastasizing to maxillofacial bones
BACKGROUND: Melanomas are malignant neoplasm of melanocytic origin, commonly seen on skin and various mucous membranes. Melanomas are the commonest intraocular malignant tumour in the adults. CASE PRESENTATION: A 50-year-old female presented with complains of painless progressive swelling in right cheek region of two months duration. Examination revealed a 6 × 4 cm bony hard swelling in right zygomatic region near and below lateral canthus of right eye with loss of vision. Investigations revealed it to be a choroidal melanoma metastatising to the zygomatic bone. Patient was successfully treated by surgery. CONCLUSION: Choroidal melanoma, which commonly metastasizes to liver and lungs, never involves the lymph nodes and metastasis to facial bones is rare. Here we report a case of choroidal melanoma metastasizing to maxillofacial bones
Sulfur Nanoparticles Synthesis and Characterization from H2S Gas, Using Novel Biodegradable Iron Chelates in W/O Microemulsion
Sulfur nanoparticles were synthesized from hazardous H2S gas using novel biodegradable iron chelates in w/o microemulsion system. Fe3+–malic acid chelate (0.05 M aqueous solution) was studied in w/o microemulsion containing cyclohexane, Triton X-100 andn-hexanol as oil phase, surfactant, co-surfactant, respectively, for catalytic oxidation of H2S gas at ambient conditions of temperature, pressure, and neutral pH. The structural features of sulfur nanoparticles have been characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS), diffused reflectance infra-red Fourier transform technique, and BET surface area measurements. XRD analysis indicates the presence of α-sulfur. TEM analysis shows that the morphology of sulfur nanoparticles synthesized in w/o microemulsion system is nearly uniform in size (average particle size 10 nm) and narrow particle size distribution (in range of 5–15 nm) as compared to that in aqueous surfactant systems. The EDS analysis indicated high purity of sulfur (>99%). Moreover, sulfur nanoparticles synthesized in w/o microemulsion system exhibit higher antimicrobial activity (against bacteria, yeast, and fungi) than that of colloidal sulfur
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