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Pavan Brahmamdam Stephen L. Carveth Mary Smyth Brian S. Gendelman M. Jeffrey Maisels 《Journal of pediatric surgery》2019,54(9):1800-1803
PurposeTo examine what proportion of caregivers, if given a choice, would choose medical versus surgical treatment of appendicitis and what factors would be important in their decision.MethodsA survey was devised and given to the caregivers of children presenting to the pediatrician for a routine visit in community and academic pediatric clinics. The survey presented a summary of outcomes after medical (non-operative) and surgical treatment of uncomplicated appendicitis. Participants were then asked to choose medical versus surgical treatment if their child were to develop appendicitis. They were also asked to rate the importance of certain factors in their decision ? 1 being “not important” and 5 being “very important”.ResultsFour hundred surveys were distributed with an 86.2% (345/400) response rate. Six percent (21/342) of respondents reported a history of appendicitis and 49.4% (168/340) reported having known someone who had appendicitis. The majority of respondents, 85.3% (284/333), were mothers. A minority of respondents, 41.7% (95% CI: 36.7, 47.0), chose medical treatment over surgery for appendicitis. There was no statistical difference in the proportion of mothers (41.6%) versus fathers who chose medical treatment (41.3%). Caregivers who chose medical treatment were more likely to rate time in hospital (p = .008) and time out of school (p = 05) as important in decision making when compared with those who chose surgery. Those who chose surgical treatment were more likely to rate risk of recurrent appendicitis (p < .001) as important to decision making. In the multivariate analysis, those who rated time in hospital as very important had more than twice the odds of choosing medical therapy (OR 2.20, p = 0.02) when compared with those who rated it as less important. Not knowing someone who has had appendicitis was significantly associated with choosing medical therapy when compared with those who do know someone who has had appendicitis, OR 2.3, p = .002. Rating pain as very important was also significantly associated with choosing medical therapy, when compared to those rating pain 1–3, OR 3.38, p = .03.ConclusionsIn this survey of caregivers of children presenting for routine care, 41.7% would choose medical, or non-operative, therapy for their children with acute appendicitis. The risk of recurrence, time in hospital, and time out of school, pain, and knowing someone who has had appendicitis were all important factors that families may consider when making a decision. These data may be useful for surgeons counseling patients on which treatment to pursue. 相似文献
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A viscoelastic constitutive model for the periodontal ligament (PDL) capable of accounting for large strains, anisotropy, and inelastic time-dependent effects was developed. Anisotropy characteristics are determined by the composite nature of the tissue and, in particular, by the distribution of collagen fibres. Time-dependent viscous phenomena are due to microstructural modifications during loading, such as fluid fluxes moving through the solid matrix and the internal rearrangement of fibers and constitutive adaptation. The viscoelastic model presented here was implemented in a general purpose finite element code. In vitro experimental tests were carried out on the PDL specimens of adult pigs to obtain stress-relaxation and cyclic stress-strain curves. The comparison of experimental and numerical results revealed good correspondence and confirmed the capability of the formulation assumed to properly interpret the viscoelastic behavior of the PDL. 相似文献
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Claudio Festuccia Vincenza Dolo Fulvio Guerra Stefania Violini Paola Muzi Antonio Pavan Mauro Bologna 《Clinical & experimental metastasis》1998,16(6):513-528
The malignant phenotype of prostatic tumor cells correlates with the expression of both uPA and itscell-membrane receptor (uPAR); however, there is little information concerning the role of cell-bound uPAin matrix degradation and invasion. Our results suggest that cell-associated uPA plays a key role in regulat-ingthe amount of plasmin present at the surface of prostatic carcinoma (PRCA) cells and show that differ-entialproduction of uPA corresponds with the capacity to bind and activate plasminogen. In addition, weprovide direct evidence that both uPA secretion and the presence of uPA-uPAR complexes characterize theinvasive phenotype of PRCA cells and suggest the existence of several pathways by which tumor cells acquireplasmin activity. LNCaP cells (which do not produce uPA but express uPAR) may activate plasmin throughexogenous uPA. In vivo, the source of uPA may be infiltrating macrophages and/or fibroblasts as observedin several other systems. PAI-1 accumulation in the conditioned medium (CM) limits plasmin action to thepericellular microenvironment. Our results indicate that MMP-9 and MMP-2 are also activated by plasmingenerated by cell-bound but not by soluble, extracellular uPA. Plasmin activation and triggering of the pro-teolyticcascade involved in Matrigel invasion is blocked by antibodies against uPA (especially by anti- A-chainof uPA which interacts with uPAR) and by PA inhibitors such as p-aminobenzamidine which mayregulate levels of cell-bound uPA. uPA may also regulate growth in PRCA cells. Indeed, antibodies againstuPA A-chain (and also p-aminobenzamidine treatment) interfere with the ATF domain and inhibit cell growthin uPA-producing PC3 and DU145 prostate cancer cell lines, whereas exogenous uPA (HMW-uPA with ATF)induces growth of LNCaP prostate tumor cell line. These data support the hypothesis that in prostatic can-cerpatients at risk of progression, uPA/plasmin blockade may be of therapeutic value by blocking both growthof the primary tumor and dissemination of metastatic cells. ©Kluwer Academic Publishers 相似文献
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Flora Hoodin Leah LaLonde Josh Errickson Kristen Votruba Rachel Kentor Erin Gatza Pavan Reddy Sung Won Choi 《Biology of blood and marrow transplantation》2019,25(2):343-353
Myeloablative conditioning allogeneic hematopoietic cell transplantation (HCT) puts patients at greater risk for significant cognitive and quality of life decline compared with recipients of reduced-intensity conditioning or autologous HCT. Vorinostat, a histone deacetylase inhibitor, has been shown to have neuroprotective and neurorestorative effects in preclinical models of neurologic diseases. Thus, within the context of a myeloablative conditioning phase II clinical trial of vorinostat combined with tacrolimus and methotrexate for graft-versus-host disease prophylaxis, we conducted an ancillary study to evaluate feasibility of assessing associations between vorinostat and neurocognitive function and quality of life (ClinicalTrials.gov NCT02409134). Nine patients (mean age, 53 years; range, 36 to 66) underwent computerized neuropsychological testing (Cogstate) and completed surveys of mood (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder-7), and quality of life (Functional Assessment of Cancer Therapy–General). Control cohorts from a separate concurrent longitudinal study (19 autologous and 18 allogeneic HCT patients, who matched the vorinostat patients on relevant medical and demographic variables) completed the same test battery. All allogeneic patients received busulfan-based myeloablative conditioning and were transplanted with HLA-matched unrelated donors. The total neurocognitive performance score of vorinostat patients did not change significantly across the study duration (ie, baseline, day 30, day 100, and day 160). Depression, anxiety, and quality of life also did not differ significantly across time. In univariate analyses (analysis of variance), vorinostat-treated patients showed no difference in neurocognitive function or quality of life compared with autologous and allogeneic control subjects. However, when medical variables were accounted for in a linear mixed effects regression model, the total neurocognitive performance of vorinostat-treated patients was comparable with autologous control subjects. Notably, autologous control subjects performed significantly better than allogeneic control subjects (estimate, .64; standard error, .23; P ≤ .01). Moreover, a smaller percentage of vorinostat-treated patients were classified as mildly, moderately, or severely impaired across neurocognitive domains as well as time points compared with both control cohorts. Thus, vorinostat may have neurorestorative or neuroprotective effects in the HCT setting. Accordingly, we recognize the need for a future, full-scale randomized controlled trial to further examine this hypothesis. 相似文献
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Human Disease Genes and Their Cloned Mouse Orthologs: Exploration of the FANTOM2 cDNA Sequence Data Set
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M Negrini A Castagnoli J V Pavan S Sabbioni D Araujo A Corallini F Gualandi P Rimessi A Bonfatti C Giunta 《Cancer research》1992,52(5):1297-1303
Viral transformation models may be useful for detecting and mapping human tumor suppressor genes. BK virus (BKV), a human papovavirus, readily transforms rodent cells but is unable to transform human cells, suggesting that oncosuppressive functions expressed in human cells control BKV oncogenic activity. We have transferred human chromosome 11 to BKV-transformed mouse cells. All of the cell clones were suppressed in the tumorigenic phenotype and anchorage-independent growth, except one clone which was nontumorigenic but maintained the ability to grow in soft agar. Cytogenetic analysis and DNA hybridization with chromosome 11-specific probes showed that all the reverted hybrids had an intact human chromosome 11, except the clone growing in semisolid medium which had lost the short arm. The results suggest that a gene located on 11p controls anchorage independence, whereas a gene on 11q controls the tumorigenicity of BKV-transformed cells. BKV T-antigen was expressed in all the hybrid clones at the same level as in the parental cell line, indicating that the putative human tumor suppressor gene(s) do not inhibit expression of the viral oncogene and must operate by another mechanism in inducing reversion of the oncogenic phenotype. Since BKV-transformed mouse cells are highly susceptible to retrovirus infection, this model can be used for searching and cloning tumor suppressor gene(s) by retrovirus-mediated "insertional mutagenesis". 相似文献
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A Akula M K Kota S G Gopisetty R V Chitrapu M Kalagara S Kalagara K K Veeravalli J P Gomedhikam 《Pharmacological research》2003,48(5):429-435
Diabetes mellitus is associated with an increased susceptibility to cardiovascular disease and it has been suggested that alterations in myocardial function may contribute to the development of diabetic cardiovascular complications. The objective of the present study is to examine the left ventricular (LV) function in streptozotocin (STZ)-induced diabetic rats in a definite course of time by non-invasive methods, i.e. M-mode and Doppler echocardiography. From the results, it was found that treatment of animals with STZ resulted in increase in blood glucose, triglycerides, cholesterol, low density lipoproteins (LDL) and decrease in serum total protein levels.Echocardiographic studies revealed that LV internal dimension (mm) during systole was significantly increased after 12 weeks of diabetes when compared to base line data of the same animals and with control animals 6.50+/-0.13 versus 4.25+/-0.17, versus 4.34+/-0.25 (P<0.05), however there was no significant change after 4-8 weeks of diabetes. Also LV internal dimension (mm) during end diastole increased significantly only after 12 weeks of diabetes than to base line data of the same animals and with control animals 7.71+/-0.34 versus 6.18+/-0.25, versus 6.25+/-0.18 (P<0.05). Fractional shortening (%), 15.69+/-5.1 versus 31.22+/-1.7, versus 30.56+/-2.1 (P<0.05), and ejection fraction (%) 37+/-2.31 versus 68.18+/-2.8, versus 60.32+/-3.5 (P<0.05), differ significantly after 12 weeks of diabetes when compared to base line data of the same animals and with control animals. E-wave (cm/s) was significantly decreased after 12 weeks of diabetes 21.11+/-1.5 versus 35.19+/-4.5, versus 32.75+/-3.0 (P<0.05), and A-wave (cm/s) was significantly increased after 12 weeks of diabetes 34.88+/-4.2 versus 19.21+/-2.8, versus 20.59+/-2.1 (P<0.05); thus, diabetic animals after 12 weeks had an inversed E/A ratio. Histological studies revealed that after 8 weeks of diabetes, necrosis was minimal, but after 12 weeks of diabetes extensive focal endomyocardial necrosis was observed. From this study, we conclude that overt LV systolic and diastolic dysfunction was fully visible at 12 weeks of diabetes on echocardiography and this non-invasive technique of echocardiography is useful in diagnosing LV dysfunction in diabetic rats without the need of invasive histopathological procedures. 相似文献