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31.
Neoplasms consisting of different cell lineages within a single skin specimen are rare, yet well documented in the literature. However, to date, there appears to be no report of invasive melanoma arising directly from the passenger melanocytes of a basal cell carcinoma (BCC). We present a case of a 91-year-old male with a suspicious lesion on the ear. Histopathology and immunohistochemical staining revealed BCC closely intertwined with invasive melanoma that exhibited foci of chondroid differentiation. The melanoma appeared to arise from the benign-appearing passenger melanocytes of the BCC and lacked connection to the overlying epidermis or an in situ component. Multiple dermatopathologists reviewed the case and agreed that the most likely explanation for the histopathologic findings was that the invasive melanoma arose from the passenger melanocytes within the BCC.  相似文献   
32.
Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein with tyrosine-kinase signaling activity, involved in many cellular functions including cell growth and differentiation. Germ line loss-of-function mutations in EGFR lead to a severe neonatal skin disorder (Online Mendelian Inheritance in Man #131550). We report 18 premature Roma children from 16 families with birthweights ranging 440–1470 g and multisystem diseases due to the homozygous mutation c.1283G˃A (p.Gly428Asp) in EGFR. They presented with thin, translucent, fragile skin (14/15), skin desquamation (10/17), ichthyosis (9/17), recurrent skin infections and sepsis (9/12), nephromegaly (10/16) and congenital heart defects (7/17). Their prognosis was poor, and all died before the age of 6 months except one 13-year-old boy with a severe skin disorder, dentinogenesis imperfecta, Fanconi-like syndrome and secondary hyperaldosteronism. Management of ion and water imbalances and extremely demanding skin care may improve the unfavorable outcome of such patients.  相似文献   
33.
The dissemination of public performance reporting (PPR) cards aims to increase utilisation of information on quality of care by consumers when making health plan choices. However, evaluations of PPR cards show that they have little impact on consumer choices. The aim of this study is to undertake a systematic review and meta-analysis of the impact of PPR cards in promoting health plan selection and switching between health plans by consumers. We searched five online databases and eight previous reviews for studies reporting findings on PPR and health plans. We extracted data and conducted quality assessment, systematic critical synthesis and meta-analyses on the included studies. We identified eight relevant health plan articles related to selection (n?=?2), switching (n?=?4), selection/switching (n?=?2). Meta-analyses showed that PPR was associated with an improvement in health plan selection and a very small deterioration in switching health plans though these changes were not statistically significant. Differences were observed between employer-sponsored health insurance and Medicare/Medicaid insurance. Given the small number of studies included in the review, further research examining the impact of PPR on health plan selection and switching in a range of insurance markets is required.  相似文献   
34.
The transient receptor potential canonical 4 (TRPC4) channel is a Ca2+-permeable nonselective cation channel in mammalian cells and mediates a number of cellular functions. Many studies show that TRPC channels are activated by stimulation of Gαq-phospholipase C (PLC)-coupled receptors. However, our previous study showed that the TRPC4 current was inhibited by co-expression of a constitutively active form of Gαq (Gαq Q209L). A shortage of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] in Gαq Q209L may be responsible for reduced TRPC4 activity. Here, we tested this hypothesis by using a rapamycin-inducible system that regulates PI(4,5)P2 acutely and specifically. Our results showed that the TRPC4β current was reduced by inducible Gαq Q209L, but not by the mutants with impaired binding ability to PLCβ. Depletion of PI(4,5)P2 by inducing the inositol polyphosphate 5-phosphatase to HEK293 cells that express TRPC4β led to an irreversible inhibition of TRPC4β currents. In contrast, inducing phosphatidylinositol 4-phosphate 5-kinase or intracellular PI(4,5)P2 application did not activate the TRPC4β current. Finally, we revealed that PI(4,5)P2 is important in delaying the desensitization of TRPC4β. Taken together, we suggest that PI(4,5)P2 is not the activator of TRPC4β activation, but it is still necessary for regulating TRPC4β activation.  相似文献   
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Background

The management of septic arthritis without bacteriological evidence is not well codified.

Aim of the work

To compare the features of septic arthritis with and without isolated germs.

Patients and Methods

This is a retrospective study including all patients with septic arthritis, discharged from the Rheumatology Department of Charles Nicolle Hospital, Tunisia over a period of 17?years [1998–2014]. The epidemiological and clinical data were evaluated. Patients were grouped according to the presence and absence of isolated germs.

Results

Fifty-nine septic arthritis patients were collected with an average of 3.5?cases/year. The mean age of the patients was 54.6?±?19?years [15–95] without sex predominance: 28 were male and 31 were female. At least one risk factor for SA was founded in 41 patients (69.5%). It was monoarticular in 50 cases (84.7%), oligoarticular in 6 (10.2%) and polyarticular in 3 (5.1%). The knee was the most often affected (49.2%). Germ was isolated in cultures and/or synovial fluids in 27 patients (45.8%). The age tended to be older in those with isolated germs and the elderly were more frequently infected compared to the non-elderly (51.8% versus 21.9%) (p?=?.01). The synovial fluid analysis, clinical and laboratory characteristics were comparable but the functional disability was significant higher in those without isolated germs (p?=?.024). Sternoclavicular joint was more common in patients with isolated germs (p?=?.016). There was no difference between the two groups regarding the course of the infection.

Conclusion

Patients with isolated and non-isolated germs have similar epidemiologic, clinical, biological and radiological characteristics.  相似文献   
37.
Rare disorders resulting in prenatal or neonatal death are genetically heterogeneous. For some conditions, affected fetuses can be diagnosed by ultrasound scan, but this is not usually possible until mid-gestation. There is often limited fetal DNA available for investigation. We investigated a strategy for diagnosing autosomal recessive lethal disorders in non-consanguineous pedigrees with multiple affected fetuses. Exome sequencing was performed to identify genes where each parent is heterozygous for a rare non-synonymous-coding or splicing variant. Putative pathogenic variants were tested for cosegregation in affected fetuses and unaffected siblings. In eight couples of European ancestry, we found on average 1.75 genes (range 0–4) where both parents were heterozygous for rare potentially deleterious variants. A proof-of-principle study detected heterozygous DYNC2H1 variants in a couple whose five fetuses had short-rib polydactyly. Prospective analysis of two couples with multiple pregnancy terminations for fetal akinesia syndrome was performed and a diagnosis was obtained in both the families. The first couple were each heterozygous for a previously reported GLE1 variant, p.Arg569His or p.Val617Met; both were inherited by their two affected fetuses. The second couple were each heterozygous for a novel RYR1 variant, c.14130-2A>G or p.Ser3074Phe; both were inherited by their three affected fetuses but not by their unaffected child. Biallelic GLE1 and RYR1 disease-causing variants have been described in other cases with fetal akinesia syndrome. We conclude that exome sequencing of parental samples can be an effective tool for diagnosing lethal recessive disorders in outbred couples. This permits early prenatal diagnosis in future pregnancies.  相似文献   
38.
5,10‐Methylenetetrahydrofolate reductase (MTHFR) deficiency is the most common inherited disorder of folate metabolism and causes severe hyperhomocysteinaemia. To better understand the relationship between mutation and function, we performed molecular genetic analysis of 76 MTHFR deficient patients, followed by extensive enzymatic characterization of fibroblasts from 72 of these. A deleterious mutation was detected on each of the 152 patient alleles, with one allele harboring two mutations. Sixty five different mutations (42 novel) were detected, including a common splicing mutation (c.1542G>A) found in 21 alleles. Using an enzyme assay in the physiological direction, we found residual activity (1.7%–42% of control) in 42 cell lines, of which 28 showed reduced affinity for nicotinamide adenine dinucleotide phosphate (NADPH), one reduced affinity for methylenetetrahydrofolate, five flavin adenine dinucleotide‐responsiveness, and 24 abnormal kinetics of S‐adenosylmethionine inhibition. Missense mutations causing virtually absent activity were found exclusively in the N‐terminal catalytic domain, whereas missense mutations in the C‐terminal regulatory domain caused decreased NADPH binding and disturbed inhibition by S‐adenosylmethionine. Characterization of patients in this way provides a basis for improved diagnosis using expanded enzymatic criteria, increases understanding of the molecular basis of MTHFR dysfunction, and points to the possible role of cofactor or substrate in the treatment of patients with specific mutations.  相似文献   
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