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21.
To estimate the incidence (any mother to child) and rate (from seropositive mother to child) of mother-to-child transmission of Trypanosoma cruzi, a serological census was conducted, targeting pregnant women and infants born to seropositive mothers, in four municipalities of El Salvador. Of 943 pregnant women, 36 (3.8%) were seropositive for T. cruzi. Of 36, 32 proceeded to serological tests of their infants when they became 6–8 months of age. Six infants seropositive at the age of 6–8 months further proceeded to second-stage serological test at the age of 9–16 months. As the result, one infant was congenitally infected. Thus, serological tests at the age of 6–8 months produced five false positives. To ensure earlier effective medication only for true positives, identification of seropositive infants at the age of 9–16 months is crucial. Incidence and rate of mother-to-child transmission were 0.14 (per 100 person-years) and 4.0%, respectively. Estimated number of children infected through mother-to-child transmission in El Salvador (170 per year) was much higher than that of human immunodeficiency virus (HIV; seven per year). It is recommended that serological testing for T. cruzi be integrated into those for HIV and syphilis as part of antenatal care package.  相似文献   
22.
Herein we report on laparoscopic donor hepatectomy (left lateral sectionectomy) for pediatric living donor liver transplantation by using a pure laparoscopic approach. Seven laparoscopic living donor procedures were performed during the period March 2016 to February 2017 at our institution. The average age of donors was 33.3 years. Preoperative liver function was normal in all donors. Four donors required 1 or more Pringle maneuver(s). The etiology was biliary atresia (n = 3), metabolic disorders (n = 2) (OTC deficiency), Alagille syndrome (n = 1), and neonatal ductopenia (n = 1). The graft was implanted orthotopically in 6 patients; we performed an auxilliary transplantation in a patient with an OTC deficiency. The time of donor surgery was 363 minutes. Dindo-Clavien complications among donors were type I (n = 1), type IIa (n = 1), and type IIb (n = 2). The mean hospital stay for the recipients was 14 days. The mean donor stay was 3.7 days. Perioperative donor and recipient mortality was 0%. Graft survival was 87.5% with 1 graft loss secondary to inadequate venous outflow. In conclusion, we can propose the laparoscopic approach in experienced centers as a “standard of practice” due to its minimal complication rate and short hospital stay.  相似文献   
23.
Gene therapy essentially consists of introducing specific genetic material into target cells without producing toxic effects on surrounding tissue. Advances over recent decades in the surgical, radiotherapeutic and chemotherapeutic treatment of oral cancer patients have not produced a significant improvement in patient survival. Increasing interest is being shown in developing novel therapies to reverse oral epithelial dysplastic lesions. This review provides an update on transfer techniques, therapeutic strategies, and the clinical applications and limitations of gene therapy in the management of oral cancer and precancer. We highlight the combination of gene therapy with chemotherapy (e.g., 5-Fluoracil) and immunotherapy, given the promising results obtained in the use of adenovirus to act at altered gene level (e.g., p53). Other techniques such as suicide gene therapy, use of oncolytic viruses or the use of antisense RNA have shown positive although very preliminary results. Therefore, further research into these promising gene therapy techniques is required to assess their true efficacy and safety in the management of these lesions.  相似文献   
24.
ObjectivesTo identify the incidence of unplanned extubations (UE) in a general intensive care unit (ICU) and associated risk factors.MethodsAn analytical, observational and prospective study was performed in an eight-bed general ICU over a 6-month period. The participants consisted of 79 consecutive patients who underwent mechanical ventilation for 12 h or more and who were under the ventilator weaning phase. The variables studied were age, days of endotracheal intubation, length of stay in the ICU, weaning phase and the APACHE II prognostic score; the degree of sedation and/or agitation was evaluated using Riker's Sedation-Agitation Scale. The incidence density of UEs was calculated and the variables measured in the extubated and non-extubated groups were compared using the Mann Whitney U-test.ResultsAmong the 79 patients studied, UE occurred in 15 (18.9%). Of these events, 76.9% occurred during the ventilator weaning phase. There were 11 cases (73.3%) of self-extubations, three cases (20%) of accidental removal and one case (6.6%) of endotracheal tube obstruction. Age equal to or less than 60 years was a risk factor. No relationship was found with the remaining factors studied: days of hospital stay, days of endotracheal intubation or APACHE score.ConclusionsPatients at risk for UE were younger and showed agitation on the Riker scale. UEs usually occurred during the ventilator weaning phase.  相似文献   
25.
Assembly of the viral genome into virions is a critical process of the virus life cycle often defining the ability of the virus to move within the plant and to be transmitted horizontally to other plants. Closteroviridae virions are polar helical rods assembled primarily by a major coat protein, but with a related minor coat protein at one end. The Closteroviridae is the only virus family that encodes a protein with similarity to cellular chaperones, a 70-kDa heat-shock protein homolog (HSP70h). We examined the involvement of gene products of Citrus tristeza virus (CTV) in virion formation and found that the chaperone-like protein plus the p61 and both coat proteins were required for efficient virion assembly. Competency of virion assembly of different CTV mutants was assayed by their ability to be serially passaged in Nicotiana benthamiana protoplasts using crude sap as inoculum, and complete and partial virus particles were analyzed by serologically specific electron microscopy. Deletion mutagenesis revealed that p33, p6, p18, p13, p20, and p23 genes were not needed for virion formation. However, deletion of either minor- or major-coat protein resulted in formation of short particles which failed to be serially transferred in protoplasts, suggesting that both coat proteins are required for efficient virion assembly. Deletion or mutation of HSP70h and/or p61 dramatically reduced passage and formation of full-length virions. Frameshift mutations suggested that the HSP70h and p61 proteins, not the RNA sequences, were needed for virion assembly. Substitution of the key amino acid residues in the ATPase domain of HSP70h, Asp(7) to Lys or Glu(180) to Arg, reduced assembly, suggesting that the chaperone-like ATPase activity is involved in assembly. Both HSP70h and p61 proteins appeared to contribute equally to assembly, consistent with coordinate functions of these proteins in closterovirus virion formation. The requirement of two accessory proteins in addition to both coat proteins for efficient assembly is uniquely complex for helical virions.  相似文献   
26.
Evidence suggests that in BALB/c mice infected with HSV-1, increased corneal scarring correlated with the presence of IL-12p40 mRNA in the cornea. To determine if this observed correlation reflected function, we have utilized mice with a homologous disruption of the gene encoding either the IL-12p35 subunit or the IL-12p40 subunit of IL-12. The severity of corneal scarring following ocular infection with HSV-1 was reduced significantly in naïve IL-12p35- and IL-12p40-deficient mice compared with naïve BALB/c mice, with the corneal scarring being low grade in the IL-12p35-deficient mice and completely absent in the IL-12p40-deficient mice. The reduction in the corneal scarring could not be attributed to a reduction in the HSV-1 titers in the eyes, which were not significantly different from the BALB/c mice, or to differences in the production of TH1 responses (IL-2 and IFN-γ production) by the infected mice. Taken together, these results suggest the importance of IL-12 in the induction of corneal scarring in HSV-1-infected mice.  相似文献   
27.
Urinary tract infections are one of the most common infections in pregnant women and may produce important consequences in the mother and fetus. Prompt diagnosis and treatment are necessary to avoid those adverse events, but antibiotic drugs are not lacked of risk. Various teratogenic or toxic effects have been described with their use. Currently, there are no sufficient data to recommend a standard regimen to treat these infections. Betalactams, nitrofurantoins, or fosfomycins are appropriate regimens when based on the culture sensitivity, but the increasing problem of antibiotic resistance makes the selection more difficult.  相似文献   
28.
BackgroundRecent evidence suggests that the number of low residue diet (LRD) days does not influence the bowel cleansing quality in non-selected patients. However, there are not data in the subgroup of patients with risk factors of inadequate bowel cleansing.ObjectiveThe aim of this study was to assess whether a 3-day LRD improved the bowel cleansing quality in patients with risk factors of poor bowel cleansing.Patients and methodsPost hoc analysis of a randomized controlled trial carried out between December 2017 and March 2018 in a tertiary care hospital. Patients with high risk of poor bowel cleansing were selected following a validated score. The patients were randomized to the 1-day LRD or 3-day LRD groups. All patients received a 2-L split-dose of polyethylene glycol plus ascorbic acid. Intention-to-treat (ITT) and per-protocol (PP) analyses were conducted for the main outcome.Results135 patients (1-day LRD group = 67, 3-day LRD = 68) were included. The rate of adequate cleansing quality was not significantly different between the groups in the ITT analysis: 76.1%, 95% CI: [64.6–84.8] vs. 79.4%, 95% CI: [68.2–87.4]; odds ratio (OR) 1.2, 95% CI [0.54–2.73]) or in the PP analysis: 77.3%, 95% CI: [65.7–85.8] vs. 80.3%, 95% CI: [69.0–88.3]; OR 1.2, 95% CI [0.52–2.77]). Compliance with the diet or cleansing solution, satisfaction or difficulties with the LRD and the polyp/adenoma detection rates were not significantly different.ConclusionOur results suggest that 1-day LRD is not inferior to 3-day LRD in patients with risk factors of inadequate bowel cleansing.  相似文献   
29.
The long flexuous virions of the Closteroviridae have a unique bipolar architecture incorporating two coat proteins, with most of the helical nucleocapsid encapsidated by the major coat protein (CP) and a small portion of one end encapsidated by the minor coat protein (CPm). It is not known whether CPm encapsidates the genomic RNA and, if so, which end and what effects transition between the two coat proteins. Two other virus-encoded proteins, an HSP70 homolog (HSP70h) and an approximately 61-kDa protein, are required to augment virion assembly. In this work, we examine the in vivo encapsidation of Citrus tristeza virus by its CPm in the absence of CP. In the absence of other assembly-related proteins, CPm protected a family of 5' coterminal RNAs, apparently because of pausing at different locations along the genomic RNA. Most of the nucleocapsids formed by CPm were short, but a few were full-length and infectious. Mutations within the 5' nontranslated region demonstrated that the CPm origin of assembly overlaps the previously described conserved stem-and-loop structures that function as a cis-acting element required for RNA synthesis. Thus, in the absence of CP, the CPm encapsidation is initiated from the 5' end of the genomic RNA. Coexpression of HSP70h and the p61 protein with CPm in protoplasts restricted encapsidation to the 5' approximately 630 nucleotides, which is close to the normal boundary of the bipolar virion, whereas the presence of either HSP70h or the p61 protein alone did not limit encapsidation by CPm.  相似文献   
30.
BACKGROUND AND OBJECTIVE: Endoscopic retrograde cholangiopancreatography (ERCP) is usually the procedure of choice for relieving bile duct obstruction. a large number of patients undergoing this intervention are geriatric population (aged 75 years of age and older). Our aim was to assess the efficacy of ERCP in this group of patients as compared to younger ones. PATIENTS AND METHODS: A retrospective study. All patients in whom a therapeutic biliary endoscopy had been performed over a four-year period of time (2002-2005) were included. RESULTS: 178 geriatric patients and 159 younger ones underwent ERCP. No differences were found in successful biliary drainage (97.7 vs. 98.7%), complication number (11.8 vs. 14.4%), or mortality rate (1.1 vs. 0.6%). On the other hand, more common bile duct stones were found in geriatric patients (57.3 vs. 39.6%, p = 0.004), and also more self-expanding metal stents were employed to drain malignant obstructive jaundice (47 vs. 8%, p = 0.0035). In the youngest group, more ERCPs were repeated in the same patients (4 vs. 10%, p = 0.001). CONCLUSIONS: The geriatric population showed similar success and morbidity and mortality rates when compared to younger patients in draining their bile duct by means of ERCP. Common bile duct stones were more frequently found in geriatric patients. No patients needing an ERCP should be excluded only because of their age.  相似文献   
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