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Type 3 immunodeficiency-associated vaccine-derived polioviruses (iVDPVs) were isolated from a 15-month-old Iranian boy with acute flaccid paralysis (AFP) who was subsequently diagnosed with X-linked agammaglobulinemia (XLA). VP1 nucleotide sequences of the two isolates differed from Sabin 3 by 2.0% and 2.1% and from each other by 0.6%. Although the key determinant of attenuation and temperature sensitivity in the 5'-untranslated region (U(472)-->C) had reverted, a second capsid-region determinant (VP3:Phe(091)) was unchanged, but a presumptive suppressor (VP1:Ala(054)-->Val) was found. The isolates were Sabin 3/Sabin 1 recombinants, sharing a single recombination breakpoint in the 2C region. Although the two isolates were antigenically distinct from Sabin 3, only one amino acid replacement was found in the neutralizing antigenic sites (VP3:Ser(059)-->Asn in site 3). The patient was placed on intravenous immunoglobulin (IVIG) therapy within 9 days of onset of AFP, and iVDPV excretion ceased thereafter, but the patient remained severely paralyzed until his death approximately 11 months after paralysis. No secondary AFP cases were found, and none of the seven tested contacts of the patient were found to be infected with poliovirus.  相似文献   
143.
Cell distribution and nutrient supply in 3D cell-laden hydrogel scaffolds are critical and should mimic the in vivo cellular environment, but been difficult to control with conventional fabrication methods. Here, we present a microfluidic direct writer (MFDW) to construct 3D cell-laden hydrogel structures with openings permitting media exchange. The MFDW comprises a monolithic microfluidic head, which delivers coaxial streams of cell-laden sodium alginate and calcium chloride solutions to form hydrogel fibers. Fiber diameter is controlled by adjusting the ratio of the volumetric flow rates. The MFDW head is mounted on a motorized stage, which is automatically controlled and moves at a speed synchronized with the speed of fiber fabrication. Head geometry, flow rates, and viscosity of the writing solutions were optimized to prevent the occurrence of curling and bulging. For continuous use, a highly reliable process is needed, which was accomplished with the integration of a declogging conduit supplying a solvent to dissolve the clogging gel. The MFDW was used for layer-by-layer fabrication of simple 3D structures with encapsulated cells. Assembly of 3D structures with distinct fibers is demonstrated by alternatively delivering two different alginate gel solutions. The MFDW head can be built rapidly and easily, and will allow 3D constructs for tissue engineering to be fabricated with multiple hydrogels and cell types.  相似文献   
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BACKGROUND:

Few effective therapeutic options exist for patients with refractory diffuse large B‐cell lymphoma (DLBCL). YM155 is a survivin suppressant with activity against DLBCL in a phase I trial. This phase II study was conducted to better characterize the toxicity and efficacy of this small molecule in patients with refractory DLBCL.

METHODS:

Forty‐one patients with a median age of 66 years and 3 prior regimens were enrolled and treated with a YM155 dose of 5 mg/m2/d by continuous infusion for 168 hours every 21 days for up to 15 cycles of treatment. The median number of completed cycles was 3.

RESULTS:

One patient had a complete remission (CR) (2.4%) with an additional 2 patients (5.9%) responding, with a median progression‐free survival of 58 days.

CONCLUSIONS:

YM155 was well tolerated with major toxicities including anemia and fatigue. Whereas YM155 had limited single‐agent activity, preclinical data suggest its role in combination with other agents, including rituximab, and a study of that combination in ongoing. Cancer 2012;118: 3128–34. © 2011 American Cancer Society.  相似文献   
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Laboratory studies have suggested a role for cholesterol in the pathogenesis of both osteoporosis and atherosclerosis. The purpose of this prospective study was to assess whether cholesterol levels, repeatedly measured over three decades in young and middle-aged adult women and men, predicted bone mineral density (BMD) at advanced age. Study participants included 712 women and 450 men enrolled in the Framingham Osteoporosis Study, aged 32-61 years at baseline (1953-55) who underwent bone densitometry 34 years later (1988-1989). BMD was measured at the proximal femur (neck, trochanter, and Ward's triangle) and lumbar spine using dual-photon absorptiometry and at the one-third radial shaft and ultradistal radius using single-photon absorptiometry. Sex-specific multivariable linear regression was used to model each BMD site as a function of total cholesterol level, adjusted for age, cigarette smoking, alcohol consumption, body mass index, systolic blood pressure, diabetes, and estrogen use (women). No significant association between total cholesterol and BMD was found in women for any of the bone sites considered. For example, adjusted mean BMD at the lumbar spine was similar in women from the lowest to highest quartile of total cholesterol, respectively, 1.07, 1.08, 1.06, 1.07 g/cm2; P for trend=0.98. Similarly, the findings in men largely showed no association between cholesterol and BMD, although there was an isolated finding of a statistically significant trend in decreasing mean radial shaft BMD with increasing total cholesterol, 0.73, 0.72, 0.72, 0.70 g/cm2, lowest to highest quartile, P for trend=0.02. Cholesterol levels in women and men from young adulthood to middle age years do not appear to have long-term clinical implications for osteoporosis later in life.  相似文献   
148.
Severe Combined Immunodeficiency (SCID) consists of a heterogeneous group of genetic disorders characterized by an arrest in T lymphocyte development which is variably associated with an abnormal differentiation of B and NK cells. In order to depict the clinical state of Iranian patients with SCID, records of forty patients were reviewed. Patients were classified based on the flow cytometry data in two groups of B- and B+. In thirty two families (80%) parents were consanguine and in 17 families (50%) there were affected members other than proband. We showed that autosomal forms of SCID might be more frequent due to higher rate of consanguineous marriages. Alongside several infective complications, complicated Bacillus Calmette-Guérin (BCG) vaccination was documented in 18 cases (45%) following the routine vaccination at birth. BCG immunization is still a part of standard vaccination for newborns in developing countries; whereas in communities with a better health condition it could be held for a few months and performed for kids whose immune system sounds intact. We discuss where consanguine mating is common, a test of screening should be run timely. A complete blood count of cord blood could reveal lymphocytopenia at birth; this helps early diagnosis. Genetic consultation would help the families with affected members preventing new SCID offspring.  相似文献   
149.
OBJECTIVE: To determine the prevalence of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms in women of different ethnic groups and to relate these common mutations to plasma homocysteine, red cell folate, and serum folate. DESIGN: A one-time fasting blood sample was obtained for MTHFR genotype (C677T and A1298C) determinations (n=433). Serum folate, red cell folate, and homocysteine analyses were performed in nonfolic acid supplement users (n=215). SUBJECTS/SETTING: This study involved 433 women from four ethnic groups, including 193 Hispanic women of Mexican descent, 139 white women, 53 Asian women of mixed descent, and 48 African American women. STATISTICAL ANALYSIS PREFORMED: Chi;(2), t Test, and analysis of variance were used. RESULTS: Mexican women (18.1%) had a higher frequency of the 677 TT genotype compared with white (7.2%), Asian (3.8%), and African American (0%) women. White women (7.9%) had a higher frequency of the 1298 CC genotype than the other ethnic groups (range=1.9% to 2.6%). The frequency of compound heterozygosity (677 CT + 1298 AC) was higher in Mexican (17.6%) and white (15.1%) women than Asian and African American ( approximately 4% to 6%) women. In the era of folic acid fortification, neither genotype, independently or together, was associated with homocysteine or blood folate concentrations when ethnic groups were combined. In Mexican women, however, a linear trend (P相似文献   
150.
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