336 research outputs found
Persistence of Hepatitis C RNA in Liver Allografts Is Associated with Histologic Progression Independent of Serologic Viral Clearance
Background. Hepatitis C virus (HCV) nondetectability in the liver may predict a sustained viral response (SVR) in patients with an end of treatment response. HCV RNA can be detected in liver tissue by in situ hybridization (ISH). Aim. To determine if HCV nondetectability in liver allografts by ISH can predict SVR in patients who cleared virus serologically on treatment. Methods. Twenty five patients with undetectable serum HCV on Interferon/Ribavirin therapy for HCV recurrence post liver transplant (LT) were studied. All had biopsies at 4 months post LT (baseline) and follow up with HCV ISH analysis performed. Results. 10 were ISH positive (group 1); 15 were ISH negative (group 2). Groups 1 and 2 had similar patient, donor, and viral characteristics at LT, as well as treatment duration at the time of the ISH assayed liver biopsy (13 ± 16 versus 10 ± 4 months P = .24). However, group 1 had longer total treatment duration (24 ± 10 versus 14 ± 5 months, P = .001). Eight (80%) group 1 and 9 (60%) group 2 patients achieved SVR. Mean grade and stage (modified Ishak score) were similar at 4 months, however, group 1 had higher grade (3 ± 1.7 versus 1.6 ± 1.3, P = .039) and stage (1.4 ± 1.4 versus 0.5 ± 0.6, P = .084) on the ISH assayed biopsy, after similar post LT intervals (23 ± 10 versus 24 ± 12 months, P = .91). Conclusion. Allograft HCV ISH nondetectability does not predict SVR in treatment responsive HCV recurrence, but is associated with less severe histologic disease
Characterization of begomoviruses sampled during severe epidemics in tomato cultivars carrying the Ty-1 gene
Tomato yellow leaf curl virus (TYLCV, genus Begomovirus, family Geminiviridae) is a major species that causes a tomato disease for which resistant tomato hybrids (mainly carriers of the Ty-1/Ty-3 gene) are being used widely. We have characterized begomoviruses severely affecting resistant tomato crops in Southeast Spain. Circular DNA was prepared from samples by rolling circle amplification, and sequenced by massive sequencing (2015) or cloning and Sanger sequencing (2016). Thus, 23 complete sequences were determined, all belonging to the TYLCV Israel strain (TYLCV-IL). Massive sequencing also revealed the absence of other geminiviral and beta-satellite sequences. A phylogenetic analysis showed that the Spanish isolates belonged to two groups, one related to early TYLCV-IL isolates in the area (Group 1), and another (Group 2) closely related to El Jadida (Morocco) isolates, suggesting a recent introduction. The most parsimonious evolutionary scenario suggested that the TYLCV isolates of Group 2 are back recombinant isolates derived from TYLCV-IS76, a recombinant virus currently predominating in Moroccan epidemics. Thus, an infectious Group 2 clone (TYLCV-Mu15) was constructed and used in in planta competition assays against TYLCV-IS76. TYLCV-Mu15 predominated in single infections, whereas TYLCV-IS76 did so in mixed infections, providing credibility to a scenario of co-occurrence of both types of isolates
Lung Ultrasound, Clinical and Analytic Scoring Systems as Prognostic Tools in SARS-CoV-2 Pneumonia: A Validating Cohort
At the moment, several COVID-19 scoring systems have been developed. It is necessary to
determine which one better predicts a poor outcome of the disease. We conducted a single-center
prospective cohort study to validate four COVID-19 prognosis scores in adult patients with confirmed
infection at ward. These are National Early Warning Score (NEWS) 2, Lung Ultrasound Score
(LUS), COVID-19 Worsening Score (COWS), and Spanish Society of Infectious Diseases and Clinical
Microbiology score (SEIMC Score). Our outcomes were the combined variable “poor outcome” (noninvasive mechanical ventilation, intubation, intensive care unit admission, and death at 28 days) and
death at 28 days. Scores were analysed using univariate logistic regression models, receiver operating
characteristic curves, and areas under the curve. Eighty-one patients were included, from which
21 had a poor outcome, and 9 died. We found a statistically significant correlation between poor
outcome and NEWS2, LUS > 15, and COWS. Death at 28 days was statistically correlated with NEWS2
and SEIMC Score although COWS also performs well. NEWS2, LUS, and COWS accurately predict
poor outcome; and NEWS2, SEIMC Score, and COWS are useful for anticipating death at 28 days.
Lung ultrasound is a diagnostic tool that should be included in COVID-19 patients evaluation
Ending cervical cancer: A call to action.
The outlook for elimination of the scourge of cervical cancer is bright, because we now have the tools to achieve this goal. In recent years human papillomavirus (HPV) vaccination in high-income countries has resulted in dramatic decreases in HPV infection and associated cervical disease. If all countries with a substantial burden of disease introduce the vaccine nationally, we can protect the vast majority of women and girls most at risk. For women who are beyond the vaccination target age, progress has been made in screening and treatment for cervical precancer, but we must accelerate this momentum to reduce incidence and mortality worldwide to the very low rates found in wealthier countries. Human and financial resources must be increased and directed to programs that follow best practices and reach all women, including the marginalized or disadvantaged. Seven key actions are recommended. Now is the time for action at national, regional, and global levels
Mobile phone based mini-spectrometer for rapid screening of skin cancer
We demonstrate a highly sensitive mobile phone based spectrometer that has potential to detect cancerous skin lesions in a rapid, non-invasive manner. Earlier reports of low cost spectrometers utilize the camera of the mobile phone to image the field after moving through a diffraction grating. These approaches are inherently limited by the closed nature of mobile phone image sensors and built in optical elements. The system presented uses a novel integrated grating and sensor that is compact, accurate and calibrated. Resolutions of about 10 nm can be achieved. Additionally, UV and visible LED excitation sources are built into the device. Data collection and analysis is simplified using the wireless interfaces and logical control on the smart phone. Furthermore, by utilizing an external sensor, the mobile phone camera can be used in conjunction with spectral measurements. We are exploring ways to use this device to measure endogenous fluorescence of skin in order to distinguish cancerous from non-cancerous lesions with a mobile phone based dermatoscope
Helical peptides from VEGF and Vammin hotspots for modulating the VEGF-VEGFR interaction
The design, synthesis, conformational studies and binding affinity for VEGF receptors of a collection of linear and cyclic peptide analogues of the N-terminal α-helix fragments 13-25 of VEGF and 1-13 of Vammin are described. Linear 13(14)-mer peptides were designed with the help of an AGADIR algorithm and prepared following peptide solid-phase synthetic protocols. Cyclic peptide derivatives were prepared on-resin from linear precursors with conveniently located Glu and Lys residues, by the formation of amide linkages. Conformational analysis, CD and NMR, showed that most synthesized peptides have a clear tendency to be structured as α-helices in solution. Some of the peptides were able to bind a VEGFR-1 receptor with moderate affinity. In addition to the described key residues (Phe17, Tyr21 and Tyr25), Val14 and Val20 seem to be relevant for affinity.Peer Reviewe
Loperamide Therapy for Acute Diarrhea in Children: Systematic Review and Meta-Analysis
BACKGROUND: Loperamide is widely used in adults for acute diarrhea. However, its use in children has been discouraged by the World Health Organization and the American Academy of Pediatrics owing to concerns over safety and efficacy in young children. METHODS AND FINDINGS: To assess the efficacy and adverse effects of loperamide compared with placebo for acute diarrhea in children, we reviewed Medline, EMBase, the Cochrane Central Register of Controlled Trials, and bibliographies of known clinical trials and of review articles, and we also interviewed key investigators in the field. We undertook a systematic review and meta-analysis of randomized controlled trials of children younger than 12 y of age with acute diarrhea, comparing loperamide with placebo. Included trials reported data on diarrhea duration or severity, or provided data on adverse effects. Compared with patients who received placebo, patients allocated to loperamide were less likely to continue to have diarrhea at 24 h (prevalence ratio 0.66, 95% confidence interval [CI]: 0.57 to 0.78), had a shorter duration of diarrhea by 0.8 d (95% CI: 0.7 to 0.9 d), and had a lower count of stools at 24 h (0.84, 95% CI: 0.77 to 0.92). Results were similar when random-effects summaries were estimated. Serious adverse events, defined as ileus, lethargy, or death, were reported in eight out of 927 children allocated to loperamide (0.9%, 95% CI: 0.4% to 1.7%). Serious adverse events were not reported in any of the 764 children allocated to placebo (0%, 95% CI: 0% to 0.5%). Among the children allocated to loperamide, serious adverse events were reported only among children younger than 3 y. CONCLUSIONS: In children who are younger than 3 y, malnourished, moderately or severely dehydrated, systemically ill, or have bloody diarrhea, adverse events outweigh benefits even at doses ≤0.25 mg/kg/d. In children who are older than 3 y with no/minimal dehydration, loperamide may be a useful adjunct to oral rehydration and early refeeding
Genetic and Phenotypic Characterization of the Etiological Agent of Canine Orchiepididymitis Smooth Brucella sp. BCCN84.3
Members of the genus Brucella cluster in two phylogenetic groups: classical and non-classical species. The former group is composed of Brucella species that cause disease in mammals, including humans. A Brucella species, labeled as Brucella sp. BCCN84.3, was isolated from the testes of a Saint Bernard dog suffering orchiepididymitis, in Costa Rica. Following standard microbiological methods, the bacterium was first defined as "Brucella melitensis biovar 2." Further molecular typing, identified the strain as an atypical "Brucella suis." Distinctive Brucella sp. BCCN84.3 markers, absent in other Brucella species and strains, were revealed by fatty acid methyl ester analysis, high resolution melting PCR and omp25 and omp2a/omp2b gene diversity. Analysis of multiple loci variable number of tandem repeats and whole genome sequencing demonstrated that this isolate was different from the currently described Brucella species. The smooth Brucella sp. BCCN84.3 clusters together with the classical Brucella Glade and displays all the genes required for virulence. Brucella sp. BCCN84.3 is a species nova taxonomical entity displaying pathogenicity; therefore, relevant for differential diagnoses in the context of brucellosis. Considering the debate on the Brucella species concept, there is a need to describe the extant taxonomical entities of these pathogens in order to understand the dispersion and evolution
Cellular and humoral immune responses and protection against schistosomes induced by a radiation-attenuated vaccine in chimpanzees
The radiation-attenuated Schistosoma mansoni vaccine is highly effective in rodents and primates but has never been tested in humans, primarily for safety reasons. To strengthen its status as a paradigm for a human recombinant antigen vaccine, we have undertaken a small-scale vaccination and challenge experiment in chimpanzees (Pan troglodytes). Immunological, clinical, and parasitological parameters were measured in three animals after multiple vaccinations, together with three controls, during the acute and chronic stages of challenge infection up to chemotherapeutic cure. Vaccination induced a strong in vitro proliferative response and early gamma interferon production, but type 2 cytokines were dominant by the time of challenge. The controls showed little response to challenge infection before the acute stage of the disease, initiated by egg deposition. In contrast, the responses of vaccinated animals were muted throughout the challenge period. Vaccination also induced parasite-specific immunoglobulin M (IgM) and IgG, which reached high levels at the time of challenge, while in control animals levels did not rise markedly before egg deposition. The protective effects of vaccination were manifested as an amelioration of acute disease and overall morbidity, revealed by differences in gamma-glutamyl transferase level, leukocytosis, eosinophilia, and hematocrit. Moreover, vaccinated chimpanzees had a 46% lower level of circulating cathodic antigen and a 38% reduction in fecal egg output, compared to controls, during the chronic phase of infection
A physical map covering the nsv locus that confers resistance to Melon necrotic spot virus in melon (Cucumis melo L.)
Melon necrotic spot virus (MNSV) is a member of the genus Carmovirus, which produces severe yield losses in melon and cucumber crops. The nsv gene is the only known natural source of resistance against MNSV in melon, and confers protection against all widespread strains of this virus. nsv has been previously mapped in melon linkage group 11, in a region spanning 5.9 cM, saturated with RAPD and AFLP markers. To identify the nsv gene by positional cloning, we started construction of a high-resolution map for this locus. On the basis of the two mapping populations, F2 and BC1, which share the same resistant parent PI 161375 (nsv/nsv), and using more than 3,000 offspring, a high-resolution genetic map has been constructed in the region around the nsv locus, spanning 3.2 cM between CAPS markers M29 and M132. The availability of two melon BAC libraries allowed for screening and the identification of new markers closer to the resistance gene, by means of BAC-end sequencing and mapping. We constructed a BAC contig in this region and identified the marker 52K20sp6, which co-segregates with nsv in 408 F2 and 2.727 BC1 individuals in both mapping populations. We also identified a single 100 kb BAC that physically contains the resistance gene and covers a genetic distance of 0.73 cM between both BAC ends. These are the basis for the isolation of the nsv recessive-resistance gene.This work was partly funded by grants GEN2003-20237-C06-02 and AGL2003-02739 from the Spanish ‘Ministerio de Ciencia y Tecnología’.Peer reviewe
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