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111.
Times to key events in Zika virus infection and implications for blood donation: a systematic review
Justin Lessler Cassandra T Ott Andrea C Carcelen Jacob M Konikoff Joe Williamson Qifang Bi Lauren M Kucirka Derek AT Cummings Nicholas G Reich Lelia H Chaisson 《Bulletin of the World Health Organization》2016,94(11):841-849
ObjectiveTo estimate the timing of key events in the natural history of Zika virus infection.MethodsIn February 2016, we searched PubMed, Scopus and the Web of Science for publications containing the term Zika. By pooling data, we estimated the incubation period, the time to seroconversion and the duration of viral shedding. We estimated the risk of Zika virus contaminated blood donations.FindingsWe identified 20 articles on 25 patients with Zika virus infection. The median incubation period for the infection was estimated to be 5.9 days (95% credible interval, CrI: 4.4–7.6), with 95% of people who developed symptoms doing so within 11.2 days (95% CrI: 7.6–18.0) after infection. On average, seroconversion occurred 9.1 days (95% CrI: 7.0–11.6) after infection. The virus was detectable in blood for 9.9 days (95% CrI: 6.9–21.4) on average. Without screening, the estimated risk that a blood donation would come from an infected individual increased by approximately 1 in 10 000 for every 1 per 100 000 person–days increase in the incidence of Zika virus infection. Symptom-based screening may reduce this rate by 7% (relative risk, RR: 0.93; 95% CrI: 0.89–0.99) and antibody screening, by 29% (RR: 0.71; 95% CrI: 0.28–0.88).ConclusionNeither symptom- nor antibody-based screening for Zika virus infection substantially reduced the risk that blood donations would be contaminated by the virus. Polymerase chain reaction testing should be considered for identifying blood safe for use in pregnant women in high-incidence areas. 相似文献
112.
Epstein—Barr virus is a human herpes virus which, whilst found as a widespread asymptomatic infection, is also associated with certain tumours of lymphoid and epithelial origin including Burkitt's lymphoma (BL), immunoblastic lymphoma (IBL), Hodgkin's Disease (HD) and nasopharyngeal carcinoma (NPC). A unique characteristic of EBV is its ability to infect and transform primary resting B lymphocytes in vitro into permanently growing lymphoblastoid cell lines (LCLs); this effect is associated with constitutive expression of a limited set of viral genes. Interestingly, the pattern of EBV gene expression observed in LCLs in vitro is also a feature of IBLs, a tumour associated with immunosuppression. The other EBV associated tumours display a more restricted pattern of EBV latent protein expression. B cell lines can be activated in vitro into the virus replicative cycle, where a large number of viral genes associated with EBV DNA replication and virus assembly are synthesised. Whilst EBV can be detected in throat washings from seropositive individuals, the only in vivo situation where full virus replication can be reliably observed is hairy leukoplakia (HL), a benign lesion of lingual epithelium frequently found in AIDS patients. Thus, the relative contribution of lymphoid cells and epithelial cells to latent EBV infection/persistence vs replication in vivo remains controversial. Recent studies suggest that HL represents a focus of EBV replication in the absence of a truly latent infection and this supports the contention that EBV persistence resides in the lymphoid compartment. These aspects together with the role of EBV in oral diseases and the effect of certain EBV genes on the control of epithelial cell growth and differentiation will be discussed. 相似文献
113.
Hamade AM Butt I Balbisi B Ross G Al-Hourani S Al-Bahrani AZ Ammori BJ 《Surgical laparoscopy, endoscopy & percutaneous techniques》2006,16(3):156-160
Primary cannulation of the peritoneal cavity is a critical part of laparoscopic surgery. The aim of this study was to evaluate the safety and applicability of a direct blunt-port primary cannulation. The peritoneal cavity was accessed by direct trocar-port insertion at sites other than the umbilicus and avoiding abdominal scars. A 5-mm port with a smooth blunt tip conical trocar was employed using a closed technique. The closed blunt trocar-port technique for primary cannulation of the peritoneal cavity was applied in 503 of 524 patients (96%) who underwent laparoscopic surgery between 2002 and 2005. Some 199 patients (38%) had abdominal scars of previous surgery. There were no major complications, but minor complications occurred in 3 patients (0.6%). No bowel or retroperitoneal vascular injuries were encountered. The closed introduction of a blunt-tipped 5-mm port, conical-trocar is a simple technique for primary cannulation in laparoscopic surgery that allows safe and rapid access to the peritoneal. 相似文献
114.
Further studies on the interaction between human platelet membrane glycoproteins IIb and IIIa in triton X-100 总被引:3,自引:0,他引:3
Analysis of human platelet membrane proteins by crossed immunoelectrophoresis (CIE) in the presence of Triton X-100 (TX-100) has previously shown that glycoproteins (GP) IIb and IIIa are located in a single immunoprecipitate, band 16.2 To investigate whether IIb and IIIa are associated in a complex, we have analyzed TX-100-solubilized 125I-labeled membrane proteins by density gradient ultracentrifugation using 10%-40% sucrose gradients containing the nonionic detergent. studies were performed using soluble proteins derived from membranes isolated in the presence or absence of EDTA. Analysis of gradient fractions by SDS-polyacrylamide gel electrophoresis showed that in the absence of divalent cation chelation, GP IIb and IIIa penetrated well into the gradient (fractions 15-17). Analysis of fractions 15-17 by CIE revealed the presence of band 16. In contrast, when the membrane proteins were incubated with EDTA prior to or after TX-100 solubilization, IIb and IIIa remained near the top of the gradient (fractions 8-11) and gave separate immunoprecipitates during CIE. Incubation of washed platelet lysates with leupeptin, an inhibitor of the Ca2+-dependent protease of human platelets, had no effect on the shape of the band 16 immunoprecipitate. Thus, for the first time, direct evidence has been obtained that GP IIb and IIIa may form a divalent cation-mediated complex. Calibration of the sedimentation profiles using proteins of known molecular weight suggests that the complex is of limited size. Indirect evidence suggests that the complex is a heterodimer. 相似文献
115.
116.
Salmasi AM Al-Bahrani LJ Alimo A Frost P Dancy M 《American journal of hypertension》2005,18(10):1294-1299
BACKGROUND: The natural history of hypertension in healthy normotensive subjects has been described in the Framingham population. We aim to study the rate of progression to hypertension in normotensive subjects after acute myocardial infarction (AMI). METHODS: One hundred seventy-three consecutive normotensive subjects admitted to the Coronary Care Unit with AMI were studied retrospectively with prospective follow-up 4 years after AMI. All the patients who were not known to be diabetic on admission (n = 150) underwent glucose tolerance test (GTT) at 2 months after AMI. RESULTS: Among the 15 patients (8.7%) who developed hypertension, GTT was abnormal in 75% (diabetes = 3, impaired glucose tolerance = 9). There were significantly more Indo-Asians and fewer whites in the hypertensive than in the normotesive patients but they were similar in age and gender, creatinine kinase level, and rate of thrombolysis during admission for AMI. Multiple regression analysis showed that progression to hypertension was a function of the presence of anterior AMI on admission (P = .0297), abnormal GTT (P = .0156), and subsequent MI on follow-up (P = .0122), but was independent of age, gender, smoking habit, body weight, previous MI, thrombolysis, creatinine kinase level, subsequent development of heart failure, and intake of beta-adrenergic blockade or angiotensin-converting enzyme (ACE) inhibitor. Of the hypertensive patients, 47% (n = 7) died compared to 8% (n = 13) of the normotensive subjects (P < .0001). CONCLUSIONS: Progression to hypertension in normotensive subjects after AMI is determined by a combination of the site of the infarct, GTT 2 months after AMI, and subsequent development of a second MI. Systemic hypertension after AMI is associated with a high mortality. 相似文献
117.
Outcome of Long‐Term Bisphosphonate Therapy in McCune‐Albright Syndrome and Polyostotic Fibrous Dysplasia
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Bas CJ Majoor Natasha M Appelman‐Dijkstra Martha Fiocco Michiel AJ van de Sande PD Sander Dijkstra Neveen AT Hamdy 《Journal of bone and mineral research》2017,32(2):264-276
McCune‐Albright syndrome (MAS) is a rare bone disorder characterized by fibrous dysplasia (FD), endocrinopathies, and café‐au‐lait patches. FD patients have been shown to respond favorably to treatment with bisphosphonates, but data are scarce in the more severe polyostotic form (PFD), including MAS, and factors determining treatment outcome are not known, particularly in the long‐term. We evaluated the biochemical (bone turnover markers [BTMs]) and clinical (pain reduction) outcome of bisphosphonate therapy in 11 patients with MAS and 30 patients with PFD: median duration of treatment 6 years (range, 2 to 25 years). Prognostic factors for treatment outcome were identified in both groups. Patients with MAS were younger at diagnosis (p = 0.001), all had precocious puberty, and four (36%) had additional growth hormone (GH) excess associated with severe craniofacial FD. Extent of skeletal disease was more severe in MAS compared to PFD. MAS patients had higher serum alkaline phosphatase (ALP) concentrations (p = 0.005), higher skeletal burden scores (p < 0.001), and more fractures (p = 0.021). MAS patients had also higher levels of FGF‐23 (p = 0.008) and higher prevalence of hypophosphatemia (p = 0.013). Twenty‐four of 30 PFD patients (80%) demonstrated a complete clinical and biochemical response within a year of starting treatment (p = 0.015), compared to only four of 11 MAS patients (36%). There were no nonresponders. In the whole group, FGF‐23, total ALP, P1NP, and CTX positively correlated with skeletal burden scores (all p ≤ 0.001), which was the only significant risk factor for an incomplete response to bisphosphonate therapy (p < 0.01). Our data suggest a beneficial and safe outcome of long‐term bisphosphonate therapy in the majority of patients with PFD, although response to therapy was limited by the higher skeletal disease burden in MAS patients. In the PFD/MAS population studied, the only identified prognostic factor that influenced the outcome of bisphosphonate therapy was a high skeletal burden score. © 2016 American Society for Bone and Mineral Research. 相似文献
118.
Impact Microindentation: Consistency of Serial Measurements and Alterations in Patients With Paget's Disease of the Tibia
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Frank Malgo Neveen AT Hamdy Socrates E Papapoulos Natasha M Appelman‐Dijkstra 《Journal of bone and mineral research》2017,32(12):2375-2380
Impact microindentation (IMI) is a new technique for the in vivo measurement of tissue‐level properties of cortical bone in humans. To address issues related to the proper application of IMI in clinical practice and to directly examine cortical bone properties in patients with tibia pathology, we studied 11 subjects without tibia pathology and nine patients with Paget's disease of the tibia in biochemical remission after bisphosphonate treatment. Serial indentations in the tibias of both legs were performed in all subjects by a single operator until 10 adequate measurements were obtained in each tibia. In patients without Paget's disease (7 men and 4 women; mean age, 61.9 years; range, 51 to 72 years), there was no difference in mean bone material strength index (BMSi) between the dominant and nondominant leg (82.1 ± 1.3 and 81.4 ± 1.3, respectively; p = 0.606). In each individual subject studied, sequential indentations in both legs showed no trends for higher or lower values with time. The standard deviation of unnormalized bone material strength (BMSu) was also comparable between the dominant and nondominant tibia (5.3 and 4.5, respectively; p = 0.657). In patients with Paget's disease (4 men and 5 women; mean age, 69.5 years; range, 55 to 87 years), mean BMSi of the Pagetic tibia was lower, albeit nonsignificantly, than that of the contralateral nonaffected tibia (74.7 ± 1.7 and 78.7 ± 1.3, respectively; p = 0.120). In contrast to subjects without Paget's disease, the SD of adequate BMSu values was significantly larger in the Pagetic tibia compared to that of the non‐Pagetic tibia (7.6 versus 5.0, respectively, p = 0.008). These results highlight the consistency of serial IMI measurements as performed by a single operator in the presence as well as absence of tibia pathology and illustrate that the method is able to capture alterations of tissue‐level cortical bone properties in patients with Paget's disease of the tibia. © 2017 The Authors.Journal of Bone and Mineral Research Published by Wiley Periodicals Inc. 相似文献
119.
Generalized glycogen storage and cardiomegaly in a knockout mouse model of Pompe disease 总被引:3,自引:2,他引:3
Bijvoet AG; van de Kamp EH; Kroos MA; Ding JH; Yang BZ; Visser P; Bakker CE; Verbeet MP; Oostra BA; Reuser AJ; van der Ploeg AT 《Human molecular genetics》1998,7(1):53-62
Glycogen storage disease type II (GSDII; Pompe disease), caused by
inherited deficiency of acid alpha-glucosidase, is a lysosomal disorder
affecting heart and skeletal muscles. A mouse model of this disease was
obtained by targeted disruption of the murine acid alpha-glucosidase gene
(Gaa) in embryonic stem cells. Homozygous knockout mice (Gaa -/-) lack Gaa
mRNA and have a virtually complete acid alpha-glucosidase deficiency.
Glycogen-containing lysosomes are detected soon after birth in liver, heart
and skeletal muscle cells. By 13 weeks of age, large focal deposits of
glycogen have formed. Vacuolar spaces stain positive for acid phosphatase
as a sign of lysosomal pathology. Both male and female knockout mice are
fertile and can be intercrossed to produce progeny. The first born knockout
mice are at present 9 months old. Overt clinical symptoms are still absent,
but the heart is typically enlarged and the electrocardiogram is abnormal.
The mouse model will help greatly to understand the pathogenic mechanism of
GSDII and is a valuable instrument to explore the efficacy of different
therapeutic interventions.
相似文献
120.
Although embryo cryopreservation is routine for many mammalian species, it
is important to know how the fundamental cryobiology of these cells changes
with development. Progressive cleavage divisions result in a reduction in
the blastomere surface area available for water and cryoprotectant mass
transport. Therefore, the membrane permeability of murine oocytes, zygotes,
2-cell, 4-cell, and 8-cell embryos to water (Lp), and dimethylsulphoxide
(PDMSO), and the reflection coefficient, sigma (sigma) were determined.
Oocytes or zygotes were recovered, cumulus cells removed, then cultured
until use. Oocytes and embryos were immobilized and perfused with treatment
solutions at 24 degrees C. Osmotically induced cell volume changes over
time were videotaped followed by image analysis. The Lp values in the
presence of dimethylsulphoxide (DMSO) were 0.77, 0.81, 0.94, 0.86, and 1.10
microm/min/atm, and the PDMSO values were 1.85, 2.04, 2.41, 1.95, and
1.25x10(-3) cm/min for oocytes, zygotes, 2, 4, and 8-cell embryos
respectively. The Lp values in the presence of DMSO were significantly (P
< 0.05) higher than those in the absence of DMSO. Treating the whole
embryo as a single osmotic entity leads to significantly (P < 0.05)
elevated PDMSO estimates relative to those based upon measurements of
individual blastomeres. These data indicate that both Lp and PDMSO
estimates are lower when predicted on an individual blastomere basis. The
data also show that neither Lp nor PDMSO differ among oocytes, zygotes,
2-cell and 4-cell embryos. However, the significantly higher Lp and lower
PDMSO of the 8-cell stage support the hypothesis that fundamental
cryobiological differences may require developmental stage- specific embryo
cryopreservation protocols.
相似文献