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141.
We report on a 28-year old woman carrying a 0.8 Mb de novo interstitial deletion in 19q13.32 detected by high-resolution array-CGH. She has severe mental retardation, tetralogy of Fallot, cleft lip and palate, deafness, megacolon and other dysmorphic features. Only a few cases of constitutional deletions located at the long arm of chromosome 19 have been previously described and this is the first report involving 19q13.32. The deleted region encompasses 15 genes, among which 3 candidate genes for genotype–phenotype correlation could be delineated. Since SLC8A2 is broadly expressed in brain and plays a potential role during embryonic development, its haploinsufficiency could possibly be related to mental retardation; as it is also expressed in aortic and intestinal smooth muscles, SLC8A2 could be related to the aortic defect of the complex cardiac malformation and to the megacolon. SAE1, a SUMO-1 activating enzyme subunit, may be related to cleft lip and palate. KPTN coding region may be a candidate gene for hearing loss. Further experimental studies on either in vivo models or diagnostic materials are needed to elucidate the role of these potential candidate genes for the phenotypic abnormalities observed in the investigated patient.  相似文献   
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Background  The geometry of lockable, ratchet, or jamming sliding surgical knots was assessed to enhance practical and topological understanding of knots among surgeons. Methods  Using a database of more than 100 surgical knots, 29 knots that reportedly feature locking, ratchet, or jamming mechanisms were topologically assessed for their ability to lock antegradely or retrogradely, to lock by assuming their flat geometry, or to jam. Results  Eighteen of the 29 investigated surgical knots have previously been mistakenly categorized. Topologically, the concept of a true ratchet knot is a fallacy. Conclusions  Surgical knots may be consistently classified on the basis of precise and detailed definition of various anti-backsliding geometrical characteristics of knots.  相似文献   
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Toll-like receptors (TLRs) can detect endogenous danger molecules released upon tissue injury resulting in the induction of a proinflammatory response. One of the TLR family members, TLR4, is constitutively expressed at RNA level on renal epithelium and this expression is enhanced upon renal ischemia/reperfusion (I/R) injury. The functional relevance of this organ-specific upregulation remains however unknown. We therefore investigated the specific role of TLR4 and the relative contribution of its two downstream signaling cascades, the MyD88-dependent and TRIF-dependent cascades in renal damage by using TLR4−/−, MyD88−/− and TRIF-mutant mice that were subjected to renal ischemia/reperfusion injury. Our results show that TLR4 initiates an exaggerated proinflammatory response upon I/R injury, as reflected by lower levels of chemokines and infiltrating granulocytes, less renal damage and a more preserved renal function in TLR4−/− mice as compared to wild type mice. In vitro studies demonstrate that renal tubular epithelial cells can coordinate an immune response to ischemic injury in a TLR4-dependent manner. In vivo we found that epithelial- and leukocyte-associated functional TLR4 contribute in a similar proportion to renal dysfunction and injury as assessed by bone marrow chimeric mice. Surprisingly, no significant differences were found in renal function and inflammation in MyD88−/− and TRIF-mutant mice compared with their wild types, suggesting that selective targeting of TLR4 directly may be more effective for the development of therapeutic tools to prevent I/R injury than targeting the intracellular pathways used by TLR4. In conclusion, we identified TLR4 as a cellular sentinel for acute renal damage that subsequently controls the induction of an innate immune response.  相似文献   
146.
The role of automated urine particle flow cytometry in clinical practice   总被引:16,自引:0,他引:16  
Urine particle flow cytometers (UFC) have improved count precision and accuracy compared to visual microscopy and offer significant labor saving. The absence of an internationally recognized reference measurement procedure, however, is a serious drawback to their validation. Chamber counting by phase contrast microscopy of supravitally-stained uncentrifuged urine is considered the best candidate for reference. The UF-100 (Sysmex Corporation, Japan) identifies RBC, WBC, squamous epithelial cells, transitional epithelial and renal tubular cells (SRC), bacteria, hyaline and inclusional casts, yeast-like cells, crystals and spermatozoa, using argon laser flow cytometry. Evaluations have established acceptable linearity over useful working ranges, with an imprecision that is consistently and significantly less than microscopy, and with negligible carry-over. Comparisons of UFC with chamber counts, quantitative urine microscopy, sediment counts, test strips, bacterial culture and urine density are reviewed. Clinical studies include diagnosis and monitoring of urinary tract infection; localization of the sites of hematuria; and diagnosis, monitoring and exclusion of renal disease. The most popular approach is to combine test strips with UFC for primary screening either always by both methods or by using test strips for analytes unrelated to particles analyzed by UFC. Expert systems now exist combining both test modalities based on user definable decision rules. The implementation of such a strategy significantly reduces microscopy review and saves time and expense without diminishing clinical utility.  相似文献   
147.
BACKGROUND: Urinalysis comprises three techniques: urinary flow cytometry, test strip analysis and determination of specific urinary proteins. We investigated the diagnostic possibilities of combining these methods for a cohort of patients with a variety of well-documented urological and nephrological pathology. METHODS: Urinary samples from 407 in- and out-patients with nephrological or urological pathology were retrospectively included in our study. Test strip analysis (URISYS 2400), urinary flow cytometry (UF-100) and urinary protein analysis [albumin, total protein, alpha1-microglobulin (A1M), alpha2-macroglobulin (A2M)] were performed. RESULTS: In discriminating upper and lower urinary tract infections, A1M and A1M/log(white blood cells) can be used, whereas pathological casts only give poor discrimination. The ratio A2M/log(red blood cells; RBC) allows differentiation between cystitis and pyelonephritis, while glomerular diseases can be recognised by the log(RBCxurinary total protein). Combining A2M and urinary albumin allows the determination of acute prostatitis. CONCLUSIONS: Using combined parameters provided by various urinalysis techniques, ratios can be proposed with diagnostic value for classifying renal and urological conditions. Possible integration in computer-based knowledge systems may offer valuable information for clinicians dealing with these pathologies.  相似文献   
148.

Purpose

Treatment options for patients with relapsed or refractory chronic lymphocytic leukemia (R/R CLL) are limited. Until recently, few effective treatment options existed, and even with the advent of new agents, studies evaluating comparative efficacy are scarce. In the Ibrutinib Versus Ofatumumab in Patients With Relapsed or Refractory Chronic Lymphocytic Leukemia (RESONATE) Phase III study, ibrutinib, an oral, once-a-day, first-in-class covalent Bruton tyrosine kinase inhibitor, improved progression-free survival (PFS) and overall survival (OS) compared with ofatumumab (PFS hazard ratio [HR] = 0.106 and OS HR = 0.369 [adjusted for crossover] at a median of 16 months’ follow-up). We sought to establish the relative efficacy of ibrutinib versus other treatment options for patients with R/R CLL using indirect comparison methods.

Methods

A systematic literature review was conducted to identify clinical trials sharing a common treatment arm with the RESONATE Phase III trial such that a network meta-analysis or indirect treatment comparisons (ITCs) could be conducted. Two trials were identified, each using the same comparator (ofatumumab) as the RESONATE study. Two pairwise ITCs were conducted using the Bucher method to establish the relative treatment efficacy of ibrutinib versus (1) idelalisib plus ofatumumab in the first study and (2) physician’s choice, defined as a mix of therapies commonly used in R/R CLL, in the second study. Odds ratios for these ITCs were calculated for overall response rate (ORR) and HRs for PFS and OS.

Findings

A strong and consistent trend of superiority for ibrutinib was observed via these ITC models with idelalisib plus ofatumumab and physician’s choice for ORR, PFS, and OS. Ibrutinib revealed prolonged PFS and OS versus comparators (PFS HR = 0.06; 95% CI, 0.04–0.11; and OS HR = 0.25; 95% CI, 0.12–0.54), physician’s choice (PFS HR = 0.41; 95% CI, 0.25–0.66; and OS HR = 0.50; 95% CI, 0.23–1.08), and idelalisib plus ofatumumab. These findings were robust and continued to favor ibrutinib when adjusting (where appropriate) for underlying differences in patient population between the trials. Some trial differences were not accounted for in the models and thus some limitations remain; however, consistency of results supports the overall findings.

Implications

In a randomized Phase III study, ibrutinib significantly improved ORR, PFS, and OS in patients with R/R CLL versus ofatumumab. In ITC models that used ofatumumab as the common comparator, ibrutinib appears to have higher ORR and longer PFS and OS versus both idelalisib plus ofatumumab and physician’s choice. In the absence of head-to-head studies and taking into consideration inherent limitations of ITCs, these models provide useful estimates of comparative efficacy.  相似文献   
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150.
Carbohydrate-deficient transferrin (CDT) is currently considered to be the best available marker for the diagnosis of chronic alcoholism. A large variety of methods have been developed, demonstrating the need for standardisation. Commercially available anion-exchange chromatographic-based assays are easy to use and require no specialised, expensive instruments. However, these methods cannot identify genetic transferrin variants or the carbohydrate-deficient glycoprotein syndrome. In 1989, a capillary isoelectric focusing method was developed for quantitative measurement of CDT. Despite the optimal resolution, this method is not easily applied in a clinical routine environment due to the complexity of analysis. Capillary electrophoresis in a polymer network using coated capillaries allowed full resolution of the sialoforms of human transferrin. The drawbacks due to an expensive and time-consuming sample preparation were eliminated when a method in neat serum was developed. Capillary zone electrophoresis allowed full resolution of the transferrin isoforms with a high analytical performance in a short analysis time thanks to a strong electroosmotic flow. Genetic transferrin variants were easily detected, avoiding false-positive results. Also, using capillary zone electrophoresis, it was shown that CDT is a suitable marker of chronic alcohol abuse detection in transferrin CD (common/cathodal) variants.  相似文献   
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