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101.
BACKGROUND: We undertook this study in order to determine the pattern and prevalence of childhood psoriasis in northern India and to highlight the differences and similarities with previous studies. MATERIALS AND METHODS: In this retrospective epidemiologic study, the data from 419 children (less than 14 years of age) with psoriasis registered at the Psoriasis Clinic between January 1990 and December 2002 were included. RESULTS: The 419 children registered at the Psoriasis Clinic constituted 0.3% of the dermatology outpatients and 12.5% of the total psoriasis patients seen over a period of 13 years in the department. There were 219 (52.2%) boys and 200 (47.7%) girls, with a male to female ratio of 1.09 : 1. The age of onset ranged from 4 days to 14 years. The mean age of onset was 8.1 +/- 2.1 years in boys and 9.3 +/- 2.3 years in girls. The peak age of onset in boys was in the 6-10-year age group, whereas the majority of girls showed an onset of psoriasis between the ages of 10 and 14 years. A positive family history was present in only 19 (4.5%) patients. The extensors of the legs were the most common initial site affected [105 (25%) cases], followed by the scalp [87 (20.7%)]. Classical plaque psoriasis was the most frequent clinical presentation [254 (60.6%) patients], followed by plantar psoriasis [54 (12.8%)]. Nail involvement was observed in 130 (31%) cases. All types of nail changes described in psoriasis were seen in these patients. Pitting was the most common nail change, followed by ridging and discoloration. Five children (1.1%) (three girls and two boys) had psoriatic arthropathy. Precipitating factors that brought about the onset of the disease or were associated with exacerbation could be recalled in only 28 (6.6%) patients. Koebnerization was observed in 27.9% of patients. Pruritus was the most frequent symptom, reported by 365 (87.1%) children. Twenty-seven (6.4%) children had other concurrent mucocutaneous diseases (vitiligo, pityriasis alba, alopecia areata, ichthyosis vulgaris, halo nevus, aphthous stomatitis, urticaria, pityriasis versicolor, nummular eczema, salmon patch, and verrucous epidermal nevus). Eighteen children had systemic disorders, including seizures, bronchial asthma, mitral regurgitation, scleroderma, Down's syndrome, high arched palate, cholelithiasis, anterior mongoloid slant, and prognathism; however, these conditions were possibly chance findings only and no correlation with the age of onset or severity of the disease was found. CONCLUSIONS: Our findings differ from those of previous studies in showing a delayed onset, equal sex distribution, less frequent facial involvement, uncommon guttate lesions, more frequent involvement of the soles, and a less frequent history of familial occurrence.  相似文献   
102.
Renal magnetic resonance imaging   总被引:3,自引:0,他引:3  
PURPOSE OF REVIEW: Current magnetic resonance imaging systems allow the visualization of normal and diseased kidney, with exquisite resolution of renal structures. Dynamic contrast magnetic resonance imaging has the potential, unique among all noninvasive modalities, to differentiate diseases that affect different portions of the vascular-nephron system. This article reviews the most important recently published studies in selected topics chosen because of their clinical relevance or potential for technical developments. RECENT FINDINGS: Magnetic resonance imaging is used increasingly to evaluate renal masses, the prenatal genitourinary system, urinary obstruction and infection, renal vasculature, and the kidneys of transplant donors and recipients. Dynamic contrast magnetic resonance renography based on gadolinium chelated to diethylenetriamine pentaacetic acid, a safe (non-nephrotoxic) paramagnetic agent, emerges as the functional renal imaging modality of choice. Both perfusion and filtration rates can be assessed in individual kidney. SUMMARY: Magnetic resonance imaging has the potential to provide a complete anatomic, physiologic, kidney-specific evaluation. With future advances in automated image analysis methods we can expect functional renal magnetic resonance imaging to play an influential role in management of renal disease.  相似文献   
103.
INTRODUCTION: The occurrence of thrombocytopenia in the perioperative period after a liver transplant is not uncommon. However, there are few studies on persistent thrombocytopenia during the longer follow up period of patients after liver transplantation. We examined the prevalence of and contributing factors to persistent thrombocytopenia beyond 1 year post-liver transplantation. METHODS: We analyzed adult patients followed for at least 1 year posttransplant with full blood counts and abdominal scans, as well as clinical notes. RESULTS: The 35 patients of mean age at transplant of 50 years and showed a mean follow-up of about 4 years showed a prevalence of persistent thrombocytopenia at 12 months of 54% and at 3 years of 25%. Factors that were associated with persistent thrombocytopenia were pretransplant variceal bleeding, splenomegaly, and thrombocytopenia at 3 and 6 months posttransplant. After multivariate analysis only the latter represented independent factors for persistent thrombocytopenia at 1 and 3 years posttransplant, respectively. CONCLUSION: Persistent thrombocytopenia improved over time posttransplant; no bleeding problem was observed among the affected cases.  相似文献   
104.
INTRODUCTION: One of the major concerns in liver transplant patients who survive past 1 year posttransplant is the development of chronic diseases. AIM: We studied two important clinical conditions that can have a chronic course-renal impairment and diabetes mellitus-among long-term liver transplant survivors. METHODS: All adult patients transplanted and followed for at least 1 year were evaluated for clinical status, blood tests, and imaging studies. The occurrence and development of renal impairment, defined as a serum creatinine above 125 micromol/L or creatinine clearance less than 75 mL/min, or diabetes mellitus were evaluated for contributing factors. RESULTS: The 35 evaluated patients of mean age at transplant of 50 years had a mean follow-up duration of 45 months. The incidence of posttransplant renal impairment was 22.8% at 1 year and 47.6% at 3 years. This disorder was associated with pretransplant renal impairment and with a diagnosis of diabetes. Posttransplant diabetes mellitus was observed in 48.6% with 41.1% resolving over time. CONCLUSION: Posttransplant renal impairment appears to be a potential long-term problem. Although this relates to pretransplant conditions, longer follow-up is required to examine whether posttransplant factors contribute to its progression.  相似文献   
105.
PURPOSE: Ashwagandha is regarded as a wonder shrub of India and is commonly used in Ayurvedic medicine and health tonics that claim its variety of health-promoting effects. Surprisingly, these claims are not well supported by adequate studies, and the molecular mechanisms of its action remain largely unexplored to date. We undertook a study to identify and characterize the antitumor activity of the leaf extract of ashwagandha. EXPERIMENTAL DESIGN: Selective tumor-inhibitory activity of the leaf extract (i-Extract) was identified by in vivo tumor formation assays in nude mice and by in vitro growth assays of normal and human transformed cells. To investigate the cellular targets of i-Extract, we adopted a gene silencing approach using a selected small hairpin RNA library and found that p53 is required for the killing activity of i-Extract. RESULTS: By molecular analysis of p53 function in normal and a variety of tumor cells, we found that it is selectively activated in tumor cells, causing either their growth arrest or apoptosis. By fractionation, purification, and structural analysis of the i-Extract constituents, we have identified its p53-activating tumor-inhibiting factor as with a none. CONCLUSION: We provide the first molecular evidence that the leaf extract of ashwagandha selectively kills tumor cells and, thus, is a natural source for safe anticancer medicine.  相似文献   
106.
107.
Two novel lectins were purified from rhizomes of two sweet flag species, namely Acorus calamus (Linn.) and Acorus gramineus (Solandin Ait.) by affinity chromatography on mannose linked epoxy-activated Sepharose 6B. The apparent molecular mass of the lectins, as determined by gel filtration chromatography, was 56 kDa for ACL and 55 kDa for AGL. In SDS-PAGE, pH 8.3, both lectins migrated with a subunit molecular mass of 13.6 kDa and 13.5 kDa, respectively, under reducing and non-reducing conditions thus indicating the absence of disulphide linkages. Acorus lectins readily agglutinated rabbit, rat and guinea pig erythrocytes. Both ACL and AGL also reacted with RBCs from sheep, goat and human ABO blood groups after neuraminidase treatment. ACL and AGL were inhibited by mannose/glucose and their derivatives. The most effective inhibitor was methyl-alpha-D-mannopyranoside. Acorus lectins were stable up to 55 degrees C, did not require metal ions for their activity and were also affected by high concentrations of denaturants like urea, thiourea and guanidine-HCl. These lectins showed potent mitogenic activity towards mouse splenocytes and human lymphocytes. Both ACL and AGL also significantly inhibited the growth of J774, a murine macrophage cancer cell-line and to lesser extent WEHI-279, a B-cell lymphoma.  相似文献   
108.
alpha-Santalol, an active component of sandalwood oil, has been studied in detail in recent years for its skin cancer preventive efficacy in murine models of skin carcinogenesis; however, the mechanism of its efficacy is not defined. Two major biological events responsible for the clonal expansion of transformed/initiated cells into tumors are uncontrolled growth and loss of apoptotic death. Accordingly, in the present study, employing human epidermoid carcinoma A431 cells, we assessed whether alpha-santalol causes cell growth inhibition and/or cell death by apoptosis. Treatment of cells with alpha-santalol at concentrations of 25-75 microM resulted in a concentration- and a time-dependent decrease in cell number, which was largely due to cell death. Fluorescence-activated cell sorting analysis of Annexin V/propidium iodide (PI) stained cells revealed that alpha-santalol induces a strong apoptosis as early as 3 h post-treatment, which increases further in a concentration- and a time-dependent manner up to 12 h. Mechanistic studies showed an involvement of caspase-3 activation and poly(ADP-ribose) polymerase cleavage through activation of upstream caspase-8 and -9. Further, the treatment of cells with alpha-santalol also led to disruption of the mitochondrial membrane potential and cytochrome c release into the cytosol, thereby implicating the involvement of the mitochondrial pathway. Pre-treatment of cells with caspase-8 or -9 inhibitor, pan caspase inhibitor or cycloheximide totally blocked alpha-santalol-caused caspase-3 activity and cleavage, but only partially reversed apoptotic cell death. This suggests involvement of both caspase-dependent and -independent pathways, at least under caspase inhibiting conditions, in alpha-santalol-caused apoptosis. Together, this study for the first time identifies the apoptotic effect of alpha-santalol, and defines the mechanism of apoptotic cascade activated by this agent in A431 cells, which might be contributing to its overall cancer preventive efficacy in mouse skin cancer models.  相似文献   
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