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51.
PURPOSE: To study child-parent similarities and the heritability of corneal shape by applying a variance component model to videokeratographic data. METHODS: Sixteen astigmatic (keratometric cylinder >/= 1.0 D) and 18 nonastigmatic (keratometric cylinder < 1.0 D) children, 7-14 years of age (mean age, 9.5 years), were enrolled with their parents. Corneal curvature, corneal astigmatism (axis and magnitude), asphericity, corneal uniformity index, and Rabinowitz McDonnell inferior-superior dioptric asymmetry value (I-S value), as well as spherical and astigmatic topographic patterns, were determined by a corneal topographer. Child-parent comparisons were assessed through a 1-way analysis of variance and the chi test. For corneal curvature, corneal astigmatism, and asphericity, heritability was estimated by a variance component model after adjustments were made for age and sex. RESULTS: Both astigmatic and nonastigmatic children showed steeper keratometric values than their parents (P < 0.05). The axis values of corneal astigmatism showed no statistically significant difference (P = 0.684) between astigmatic offspring and their parents, whereas the magnitude values were significantly higher (P < 0.001) in astigmatic children. Altogether, 68% (95% confidence interval [CI], 66%-72%) of child-parent comparisons showed the same topographic pattern between parents and their offspring. Heritability values (48%; 95% CI, 36%-57%) were statistically significant for corneal curvature (P < 0.00001) and <30% for corneal astigmatism and asphericity. CONCLUSIONS: The application of a variance component model to videokeratographic child-parent comparisons suggests that the genetic contribution to corneal shape affects corneal curvature rather than corneal astigmatism.  相似文献   
52.
Occupational skin diseases are very common among hairdressers. The aim of our study was to evaluate the frequency, the age distribution and the source of contact sensitization in a group of 209 hairdressers who consulted our Clinic from 1990 to 1999. One hundred and thirty-two patients showed one or more clinically relevant positive reactions to different allergens; 89 of them were positive to the hairdressers' series and 43 were positive to other allergens. Para-phenylenediamine base and para-toluenediamine sulphate caused the greatest number of positive reactions (77 and 29 respectively). Both glyceryl monothioglycolate and ammonium persulphate gave 25 positive patch tests. The allergens not included in the hairdressers' series which gave the greatest number of positive reactions were nickel sulphate and disperse dyes yellow 3, blue 124 and red 1. The allergens known as strong skin sensitizers have remained almost the same over the years. Preventive measures should be mandatory to protect hands and to improve the safety of this job.  相似文献   
53.
Flow-cytometric detection of minimal residual disease (MRD) identifies patients with high relapse risk in childhood acute lymphoblastic leukaemia (ALL). We studied the efficacy of this method in adult T-ALL treated with the Italian co-operative GIMEMA (Gruppo Italiano Malattie Ematologiche dell'Adulto) LAL0496 protocol. Bone marrow samples from 53 patients were taken at fixed treatment time points and MRD was analysed using a leukaemia-specific immunophenotype (cytoplasmic-CD3/nuclear-terminal desoxynucleotidyl transferase). The median follow-up was 17 months (range 3-61) and a median of 4.5 analyses/patient was performed (range 3-12). Six out of 53 (11.3%) patients were refractory to treatment, 30/53 (56.6%) relapsed and 17/53 (32.1%) remain in continuous complete remission. The probability of relapse at 2 years for MRD-positive patients at preconsolidation was 81.5%vs 38.9% for MRD-negative patients (P = 0.00078). This risk was still 54.5% for MRD-positive vs 15.8% for MRD-negative patients pre-third reinduction (P = 0.0098) and 50.0% for MRD-positive vs 16.4% for MRD-negative patients pre-sixth reinduction (P = 0.032). The relapse-predicting value of MRD did not depend on features at diagnosis such as age, sex and leucocyte count. Our data suggest that immunophenotypic MRD monitoring in the first year of treatment is a useful outcome predictor for adult T-ALL patients.  相似文献   
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Clinical Rheumatology - The aim of this study is to evaluate a possible negative action of lockdown, during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, in the...  相似文献   
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The human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus, is a gamma herpesvirus associated with AIDS-related body cavity-based lymphomas (BCBL), also called primary effusion lymphomas (PEL). These are a rare form of non-Hodgkin lymphomas in which HHV-8 is present, often associated with Epstein-Barr virus (EBV) infection. HHV-8 is also present in a latent state or in a state of low-level persistence in different primary effusion lymphoma-derived cell lines, such BCBL-1 cells, that lack EBV infection. This cell line was induced to produce mature virions by treatment with 12- O -tetradecanoyl phorbol-13-acetate (TPA) and the characteristic ultrastructural features of HHV-8 lytic replication were identified and compared to those of the other members of Herpesviridae family.  相似文献   
58.
Testicular germ cell tumors account for about 1% of all cancers. The incidence of these tumors is increasing and they represent the most common solid malignancies of young men aged 15–40 years with seminoma being one of the most common histotype. Pathogenesis of testicular germ cell tumors remains unknown and, although cryptorchidism is considered the main risk factor, there is evidence of an association with environmental and genetic risk factors. Human papillomaviruses (HPV) are a family of DNA viruses and represent a major risk factor for cervical cancer. In addition, they have been associated with other human non‐malignant and malignant diseases, including breast and head and neck cancer. HPV sequences have been detected throughout the male lower genitourinary tract as well as in seminal fluid and an increased testicular tumorigenesis has been reported in HPV transgenic mice. Aim of this study was to evaluate the potential involvement of HPV in human testicular tumorigenesis. Real‐time PCR employing GP5+/GP6+ consensus HPV primers was used to examine the presence of HPV sequences in a subset of human seminoma (n = 61) and normal testicles (n = 23). None of the specimens tested displayed the presence of HPV DNA. These findings do not support an association between HPV and human seminoma and warrant further studies to assess definitively the role of these viruses in human testicular tumorigenesis. J. Med. Virol. 85:105–109, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
59.
In this work, we propose that for further studies of the physiopathology and treatment for inflammatory bowel diseases, an integral view of the conditions, including the triad of microbiota–heat shock proteins (HSPs)–probiotics, ought to be considered. Microbiota is the complex microbial flora that resides in the gut, affecting not only gut functions but also the health status of the whole body. Alteration in the microbiota’s composition has been implicated in a variety of pathological conditions (e.g., ulcerative colitis, UC), involving both gut and extra-intestinal tissues and organs. Some of these pathologies are also associated with an altered expression of HSPs (chaperones) and this is the reason why they may be considered chaperonopathies. Probiotics, which are live microorganisms able to restore the correct, healthy equilibrium of microbiota composition, can ameliorate symptoms in patients suffering from UC and modulate expression levels of HSPs. However, currently probiotic therapy follows ex-adiuvantibus criteria, i.e., treatments with beneficial effects but whose mechanism of action is unknown, which should be changed so the probiotics needed in each case are predetermined on the basis of the patient’s microbiota. Consequently, efforts are necessary to develop diagnostic tools for elucidating levels and distribution of HSPs and the microbiota composition (microbiota fingerprint) of each subject and, thus, guide specific probiotic therapy, tailored to meet the needs of the patient. Microbiota fingerprinting ought to include molecular biology techniques for sequencing highly conserved DNA, e.g., genes encoding 16S RNA, for species identification and, in addition, quantification of each relevant microbe.  相似文献   
60.
Amyloid beta (Aβ) is implicated in Alzheimer's disease (AD) as an integral component of both neural toxicity and plaque formation. Brains of the longest-lived rodents, naked mole-rats (NMRs) approximately 32 years of age, had levels of Aβ similar to those of the 3xTg-AD mouse model of AD. Interestingly, there was no evidence of extracellular plaques, nor was there an age-related increase in Aβ levels in the individuals examined (2–20+ years). The NMR Aβ peptide showed greater homology to the human sequence than to the mouse sequence, differing by only 1 amino acid from the former. This subtle difference led to interspecies differences in aggregation propensity but not neurotoxicity; NMR Aβ was less prone to aggregation than human Aβ. Nevertheless, both NMR and human Aβ were equally toxic to mouse hippocampal neurons, suggesting that Aβ neurotoxicity and aggregation properties were not coupled. Understanding how NMRs acquire and tolerate high levels of Aβ with no plaque formation could provide useful insights into AD, and may elucidate protective mechanisms that delay AD progression.  相似文献   
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