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51.
Emergence of drug-resistant Plasmodium falciparum strains to conventional first-line antimalarial drugs has compelled many countries to reorient their drug policies to adopt artemisinin-based combination therapies (ACTs) for treatment of uncomplicated malaria. This has increased the demand of artemisinin, already a scarce commodity. Synthesis of artemisinin is not yet commercially viable. Extensive use of available ACTs will invariably lead to emergence of resistance to these combinations. Thus, there is need to search for new artemisinin-based synthetic, inexpensive, synergistic combinations to reduce dependence on artemisinin. In vitro cultures of P. falciparum provide an appropriate system for identification of such new combinations. We evaluated interactions of artemisinin with triclosan or ketoconazole against blood stages of P. falciparum by a fixed-ratio isobologram method. Artemisinin shows mild synergistic interaction with triclosan and slight to marked antagonism with ketoconazole in vitro. These antiplasmodial interactions, however, require confirmation using in vivo model systems.  相似文献   
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A 38-year-old farmer was apparently well until 5 years of age. At this age, the patient's mother found mildly itchy, raised eruptions over the scalp during combing of the scalp hair. Since then, the eruptions have progressed insidiously to involve the face and other parts of the body, with a preponderance over the face, upper back, and chest, including the palms. The soles, oral cavity, and genital tract were unaffected. The lesions were persistent in nature and showed no remission or exacerbation. Mild to moderate pruritus/discomfort was experienced following sunlight exposure. A prominent, raised eruption appeared on the right side of the forehead 9 years ago, 25 years after the initial eruptions, which in due course ulcerated. It was progressive in nature and acquired a large size. Two years later, it was diagnosed as squamous cell carcinoma, for which liquid nitrogen cryosurgery was performed. There was a recurrence of the lesion at the site of surgery, which was excised 4 months later. Subsequently, there was a sudden flare up at the same site. It was badly infected with maggot infestation. The relentless course of the disease was evident by the appearance of two similar lesions, one on the right half of the nose and the other on the left preauricular region. A short while ago, fatigue and loss of weight were also recorded. Bladder and bowel functions were normal and there was no loss of appetite, hoarseness of voice, or breathlessness. Four of the patient's six children (three sons and one daughter) were reported to have similar lesions all over the body. In addition, nine other relatives were also affected. Accordingly, a total of 14 (12 males and two females) family members were found to be affected from amongst 41 individuals (26 males and 15 females) spread across several generations (Fig. 1). There was a second-degree consanguinity of marriage, with the patient's grandmother and wife's father being brother and sister. Skin surface examination was marked by multiple, discrete, flat-topped, scaly, brownish-black papules of diverse morphology, from hypopigmented macules to verrucous lesions, with a few coalescing to form plaques. The scales were brown, dry, and adherent (Fig. 2a). The lesions were conspicuous by their presence over the face, neck, and front and back of the chest. The extremities were also affected. Nevertheless, the soles and genitalia were spared. The oral mucosae, hair, and nails were normal. Koebner's phenomenon was explicit, whereas Auspitz's sign was not demonstrable. In addition, a perceptible nodulo-ulcerative lesion (size, 3 in x 2 in) with indurated, raised, averted margins was encountered on the right side of the forehead. The ulcer was tender and had a fetid discharge. Necrotic slough was prominent over its base. Similar lesions were located on the left preauricular region and right half of the nose. Hematoxylin and eosin-stained sections prepared from biopsies taken from representative lesions of epidermodysplasia verruciformis and squamous cell carcinoma revealed their diagnostic features. Epidermodysplasia verruciformis showed features of hyperkeratosis and acanthosis with hardly any papillomatosis. Marginal elongation of the rete ridges was present. Extensive vacuolization was a remarkable feature, and was largely confined to the upper stratum Malpighian and the granular cell layer. Some of the vacuolated cells were fairly large; their nuclei were located in the center and had variable pyknosis. The granular cell layer was uniformly thickened, whereas the stratum corneum had a loosely felted (basket-weave) appearance. The dermis was apparently normal (Fig. 2b,c). The other microsection(s) from squamous cell carcinoma were conspicuous by the presence of hyperkeratosis, acanthosis, and irregular masses of epidermal cells, proliferating downwards and invading the dermis. Varying proportions of differentiated squamous cells formed their bulk. These cells were atypical, characterized by variations in size and shape, hyperplasia and hyperchromasia of the nuclei, absence of prickles, chas, characterization of individual cells, and the presence of both mitotic and atypical mitotic figures (Fig. 3b).  相似文献   
53.
International Ophthalmology - This study is aimed to determine the frequency, sociodemographic profile, clinical presentation, patterns of injury, treatment and outcomes of cases of...  相似文献   
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The efficacy of the larvivorous fish Poecilia reticulata against mosquito larvae was monitored in a drain at Bharat Heavy Electricals Limited, Hardwar, India. The water was polluted and the water flow was in some way impeded. Poecilia reticulata failed to feed on Culex quinquefasciatus larvae in this drain. Laboratory experiments also confirmed the inefficacy of P. reticulata as a predator of Cx. quinquefasciatus larvae during the first 24 h. Significant differences in the efficacy of P. reticulata against Cx. quinquefasciatus were recorded between polluted water and drinking water. Poecilia reticulata preferred to feed on other available food present in the polluted water rather than on Cx. quinquefasciatus larvae. This was verified by the identification of plankton in the gut content of the fish and by the high density of plankton present in the polluted water.  相似文献   
57.
A 28-year-old man with decreased libido received ashwagandha in the usual daily dosage of 5 g for 10 days. During this period, he experienced a burning and/or itching sensation as well as discoloration of the skin/mucous membrane confined to the penis. He had a similar type of eruption at the same site 6 months prior while taking ashwagandha. Examination of the skin surface was conspicuous and marked by the presence of a dusky, erythematous, oval, eroded plaque of 3 cm, affecting the glans penis and prepuce (Figure). The drug was withdrawn and topical 0.05% clobetasol propionate cream was administered along with cetrizine dihydrochloride, an H1-receptor blocker, 10 mg daily for 1 month. There was a perceptible amelioration of the lesion, resulting in residual greyish white pigmentation. He was prescribed oral drug provocation with 1 g of ashwagandha powder. Within 12 hours, a flare-up developed at the earlier site, confirming the causality.  相似文献   
58.
The venereal form of treponematosis, caused by the spirochete Treponema pallidum, plagued every major city in the preantibiotic era. "Civilization means syphilization," was an idea touted by Richard von Krafft-Ebing in the late 19th, and early 20th centuries that the effects of modern life make men more susceptible to syphilis and other diseases. Christopher Columbus was thought of as an importer of syphilis to Europe. Because his serendipitous voyages to the New World initiated the process of Spanish colonization, which foreshadowed general European colonization of the New World, it is difficult to rule out the cultural and political animosity created by Columbus and his men. These recent revelations are intriguing and may create dialogue that may subsequently challenge the age-old theory of "East to West" spread of venereal syphilis. This contribution warrants the continuation of study in this direction, taking into account skeletal studies that utilized radiocarbon dating technique and the phylogenetic analysis of the bacterial strains, offering a possible consensus on the origin and evolution of syphilis.  相似文献   
59.
Testosterone supplementation reduces total body adipose tissue (AT), but we do not know whether the effects are uniformly distributed throughout the body or are region specific, or whether they are dose related. We determined the effects of graded doses of testosterone on regional AT distribution in 54 healthy men (18-35 yr) in a 20-wk, randomized, double-blind study of combined treatment with GnRH agonist plus one of five doses (25, 50, 125, 300, or 600 mg/wk) of testosterone enanthate (TE). Total body, appendicular, and trunk AT and lean body mass were measured by dual-energy x-ray absorptiometry, and sc, intermuscular, and intraabdominal AT of the thigh and abdomen were measured by magnetic resonance imaging. Treatment regimens resulted in serum nadir testosterone concentrations ranging from subphysiological to supraphysiological levels. Dose-dependent changes in AT mass were negatively correlated with TE dose at all sites and were equally distributed between the trunk and appendices. The lowest dose was associated with gains in sc, intermuscular, and intraabdominal AT, with the greatest percent increase occurring in the sc stores. At the three highest TE doses, thigh intermuscular AT volume was significantly reduced, with a greater percent loss in intermuscular than sc depots, whereas intraabdominal AT stores remained unchanged. In conclusion, changes in testosterone concentrations in young men are associated with dose-dependent and region-specific changes in AT and lean body mass in the appendices and trunk. Lowering testosterone concentrations below baseline increases sc and deep AT stores in the appendices and abdomen, with a greater percent increase in sc depots. Conversely, elevating testosterone concentrations above baseline induces a greater loss of AT from the smaller, deeper intermuscular stores of the thigh.  相似文献   
60.
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