Síntesis de evidencia. Covid persistente / Evidence synthesis. persistent covid

El término Covid persistente fue utilizado por primera vez por la Dra. Elisa Perego, como un hashtag de Twitter en mayo de 2020. Describía su propia experiencia de una condición cíclica multifásica, que difería de la evolución clínica característica de Covid-19 tanto en sintomatología como en tiempo. El término Covid persistente o 'Long Covid' tiene varios nombres dependiendo de la literatura consultada: 'secuelas post-agudas de Covid-19', 'Covid¬-19 en curso', 'síndrome crónico de Covid', 'Covid de larga distancia' (Long haulers) y 'condición post-Covid-19', esta última es la utilizada por la Organización Mundial de la Salud (OMS) y todas son consideradas por los Centros para el Control y la Prevención de Enfermedades (CDC) como 'condiciones pos Covid. Aún no existe consenso en cuanto al reconocimiento de Covid persistente como entidad clínica, así como tampoco en cuanto a su nombre y criterios diagnósticos. Sin embargo, dada la alta prevalencia de la sintomatología a la que se le asocia, es imperativo que los servicios y las políticas de salud prioricen su atención. A la vez, es necesario efectuar estudios a futuro para identificar en detalle los diferentes subtipos de Covid persistente y, permitir así, su atención médica estratificada sin que los servicios de salud no se vean abrumados.

The term persistent Covid was used for the first time by Dr. Elisa Perego, as a Twitter hashtag in May 2020. It described her own experience of a multiphasic cyclical condition, which differed from the characteristic clinical evolution of Covid-19 both in symptomatology as in time The term persistent Covid or 'Long Covid' has several names depending on the literature consulted: 'post-acute sequelae of Covid-19', 'Covid¬-19 in progress', 'chronic Covid syndrome', 'Long-distance Covid ' (Long haulers) and 'post-Covid-19 condition', the latter is the one used by the World Health Organization (WHO) and all are considered by the Centers for Disease Control and Prevention (CDC) as ' post covid conditions. There is still no consensus regarding the recognition of persistent Covid as a clinical entity, nor regarding its name and diagnostic criteria. However, given the high prevalence of the symptoms to which it is associated, it is imperative that health services and policies prioritize care. At the same time, it is necessary to carry out future studies to identify in detail the different subtypes of persistent Covid and, thus, allow their stratified medical care without the health services being overwhelmed.

Prostate-specific Membrane Antigen PET: Therapy Response Assessment in Metastatic Prostate Cancer.

Therapy response assessment is a critical step in cancer management, leading clinicians to optimize the use of therapeutic options during the course of the disease. Imaging is a pivotal biomarker for therapy response evaluation in oncology and has gained wider use through the development of reproducible data-based guidelines, of which the Response Evaluation Criteria in Solid Tumors is the most successful example. Disease-specific criteria have also been proposed, and the Prostate Cancer Working Group 3 criteria are the mainstay for prostate cancer (PC). However, conventional imaging evaluation in metastatic PC has several limitations, including (a) the inability to detect small-volume disease, (b) the high prevalence of bone (nonmeasurable) lesions at imaging, and (c) the established role of serum prostate-specific antigen (PSA) levels as the biomarker of choice for response assessment and disease progression. In addition, there are an increasing number of newer treatment options with various effects on imaging features. Prostate-specific membrane antigen (PSMA) PET has improved patient selection for newer treatments, such as metastasis-directed therapy (MDT) or radionuclide therapy. The role of PSMA PET in response assessment for many metastatic PC therapeutic options (MDT, androgen deprivation therapy, chemotherapy, radionuclide therapy, and immunotherapy) is an evolving issue, with emerging data showing good correlation with PSA levels and clinical outcome. However, there are specific implications of each therapy (especially androgen deprivation therapy and immunotherapy) on PSMA expression by PC cells, leading to potential pitfalls and inaccuracies that must be known by radiologists. Despite some limitations, PSMA PET is addressing gaps left by conventional imaging methods (eg, CT and bone scanning) and nonimaging biomarkers (PSA levels) in metastatic PC therapy response assessment, a role that can be improved with advances like refinement of interpretation criteria and whole-body tumor burden quantification.© RSNA, 2020See discussion on this article by Barwick and Castellucci.

Sensitizing gastric adenocarcinoma to chemotherapy by pharmacological manipulation of drug transporters.

Owing to intrinsic and acquired chemoresistance, the response of gastric adenocarcinoma (GAC) to chemotherapy is very poor. Here we have investigated the role of transportome in reducing the intracellular content of anticancer drugs and conferring multidrug resistance (MDR) phenotype. Tumors specimens and paired adjacent tissue were analyzed to determine the MDR signature by TaqMan Low-Density Arrays and single-gene qPCR. Strategies of sensitization were evaluated in vitro using the GAC-derived cell line AGS and in vivo using a subcutaneous xenograft model in immunodeficient nude mice. Several transporters involved in drug uptake and export, which are present in healthy stomach, were highly expressed in GAC. In contrast, the cancer-type OATP1B3 was almost exclusively expressed in tumor tissue. The transportome profile varied depending on tumor anatomical location, differentiation, and stage. Immunofluorescence analysis revealed high MRP1 and MRP4 expression at the plasma membrane of tumor cells as well as AGS cells in culture, in which MRP inhibition resulted in selective sensitization to cytotoxic MRP substrates, such as sorafenib, docetaxel, etoposide, and doxorubicin. In mice with subcutaneous tumors formed by AGS cells, sorafenib alone failed to prevent tumor growth. In contrast, this drug induced a marked inhibitory effect when it was co-administered with diclofenac. In conclusion, MRP1 and MRP4 play an important role in the lack of response of GAC to drugs that are transported by these export pumps. Moreover, agents, such as sorafenib, considered at present useless to treat GAC, may become active antitumor drugs when co-administered with non-toxic MRP inhibitors, such as diclofenac.

Causes of hOCT1-Dependent Cholangiocarcinoma Resistance to Sorafenib and Sensitization by Tumor-Selective Gene Therapy.

Although the multi-tyrosine kinase inhibitor sorafenib is useful in the treatment of several cancers, cholangiocarcinoma (CCA) is refractory to this drug. Among other mechanisms of chemoresistance, impaired uptake through human organic cation transporter type 1 (hOCT1) (gene SLC22A1) has been suggested. Here we have investigated the events accounting for this phenotypic characteristic and have evaluated the interest of selective gene therapy strategies to overcome this limitation. Gene expression and DNA methylation of SLC22A1 were analyzed using intrahepatic (iCCA) and extrahepatic (eCCA) biopsies (Copenhagen and Salamanca cohorts; n = 132) and The Cancer Genome Atlas (TCGA)-CHOL (n = 36). Decreased hOCT1 mRNA correlated with hypermethylation status of the SLC22A1 promoter. Treatment of CCA cells with decitabine (demethylating agent) or butyrate (histone deacetylase inhibitor) restored hOCT1 expression and increased sorafenib uptake. MicroRNAs able to induce hOCT1 mRNA decay were analyzed in paired samples of TCGA-CHOL (n = 9) and Copenhagen (n = 57) cohorts. Consistent up-regulation in tumor tissue was found for miR-141 and miR-330. High proportion of aberrant hOCT1 mRNA splicing in CCA was also seen. Lentiviral-mediated transduction of eCCA (EGI-1 and TFK-1) and iCCA (HuCCT1) cells with hOCT1 enhanced sorafenib uptake and cytotoxic effects. In chemically induced CCA in rats, reduced rOct1 expression was accompanied by impaired sorafenib uptake. In xenograft models of eCCA cells implanted in mouse liver, poor response to sorafenib was observed. However, tumor growth was markedly reduced by cotreatment with sorafenib and adenoviral vectors encoding hOCT1 under the control of the BIRC5 promoter, a gene highly up-regulated in CCA. Conclusion: The reason for impaired hOCT1-mediated sorafenib uptake by CCA is multifactorial. Gene therapy capable of selectively inducing hOCT1 in tumor cells can be considered a potentially useful chemosensitization strategy to improve the response of CCA to sorafenib.

Evaluation of the promiscuous component of several bacterial export pumps TolC as a biomarker for toxic pollutants in feedstuffs.

A significant risk to the food chain is the presence of noxious pollutants in the feeds of animals whose products are used in human nutrition. Consequently, analytical methods and biosensors have been developed to detect these types of contaminates in feeds. Here we have evaluated whether the expression of TolC, a promiscuous component of several ATP-dependent efflux pumps in E. coli, up-regulated in response to chemical stress, could be a useful biomarker for this aim. Changes in TolC expression in response to toxic compounds, with different abilities to induce DNA damage, were determined using two E. coli strains with (DH5α) and without (BL21(DE3)) inactivating mutation in RecA gene. Deoxycholic acid and potassium dichromate up-regulated TolC in both strains. In contrast, cisplatin-induced TolC up-regulation was abolished in the absence of a functional RecA. When the effect of several insecticides, herbicides, antibiotics and common soil pollutants on TolC expression was analyzed, a relationship between toxicity and their ability to up-regulate TolC was observed. However, this was not a general event because the insecticide α-cipermetrin induced a reduction in cell viability, which was not accompanied by TolC up-regulation. In contrast, the soil pollutant benzene was able to stimulate TolC expression at non-toxic concentrations. When this test was used to analyze aqueous extracts from different feedstuffs, up-regulation of TolC was found in the absence of cell toxicity and was even accompanied by enhanced cell viability. In conclusion, TolC expression is partly dependent on the integrity of the RecA/LexaA system. Although toxic compounds up-regulate TolC in a dose-dependent manner, this response is also activated by non-toxic agents. Thus, owing to its poor specificity regardless of its sensitivity, the use of TolC up-regulation in E. coli to detect the presence of toxic pollutants in conventional and unconventional sources of nutrients for ruminant feeding requires supplementary biomarkers.

Biopiracy versus One-World Medicine-From colonial relicts to global collaborative concepts.

BACKGROUND: Practices of biopiracy to use genetic resources and indigenous knowledge by Western companies without benefit-sharing of those, who generated the traditional knowledge, can be understood as form of neocolonialism. HYPOTHESIS: The One-World Medicine concept attempts to merge the best of traditional medicine from developing countries and conventional Western medicine for the sake of patients around the globe. STUDY DESIGN: Based on literature searches in several databases, a concept paper has been written. Legislative initiatives of the United Nations culminated in the Nagoya protocol aim to protect traditional knowledge and regulate benefit-sharing with indigenous communities. The European community adopted the Nagoya protocol, and the corresponding regulations will be implemented into national legislation among the member states. Despite pleasing progress, infrastructural problems of the health care systems in developing countries still remain. Current approaches to secure primary health care offer only fragmentary solutions at best. Conventional medicine from industrialized countries cannot be afforded by the impoverished population in the Third World. Confronted with exploding costs, even health systems in Western countries are endangered to burst. Complementary and alternative medicine (CAM) is popular among the general public in industrialized countries, although the efficacy is not sufficiently proven according to the standards of evidence-based medicine. CAM is often available without prescription as over-the-counter products with non-calculated risks concerning erroneous self-medication and safety/toxicity issues. The concept of integrative medicine attempts to combine holistic CAM approaches with evidence-based principles of conventional medicine. CONCLUSION: To realize the concept of One-World Medicine, a number of standards have to be set to assure safety, efficacy and applicability of traditional medicine, e.g. sustainable production and quality control of herbal products, performance of placebo-controlled, double-blind, randomized clinical trials, phytovigilance, as well as education of health professionals and patients.

The lack of the organic cation transporter OCT1 at the plasma membrane of tumor cells precludes a positive response to sorafenib in patients with hepatocellular carcinoma.

BACKGROUND: Sorafenib is the drug of choice in the treatment of advanced hepatocellular carcinoma (HCC). Beneficial effects are limited by mechanisms of chemoresistance, which include downregulation and/or impaired function of plasma membrane transporters accounting for drug uptake. The organic cation transporter 1 (OCT1) plays a major role in sorafenib uptake and decreased expression in HCC has been associated with poorer response. METHODS: The multicenter retrospective TRANSFER study involved tumor biopsies from 39 patients with advanced HCC and sorafenib therapy for ≥4 wk. Endpoint was the relationship between clinicopathological features and immunohistological result. Immunostaining was performed using specific primary anti-OCT1-head and anti-OCT1-tail antibodies. Tumors were classified according to a simplified staining score as absent, weak, moderate or strong, taking into account the localization of the staining at the plasma membrane as positive or negative. RESULTS: Results confirmed OCT1 downregulation in half of the cases investigated (10% absent, 38% weak). However, only one third of tumors expressing OCT1 displayed plasma membrane location (15% vs. 36% cytosolic expression). When comparing HCC with and without OCT1 expression, no different sorafenib response was found. When tumors expressing OCT1 at the plasma membrane were considered separately, a marked longer survival was found (Log Rank p<0.001). No association between OCT1 expression at the plasma membrane with tumor stage, previous treatment with TACE or radiological response was seen.In conclusion, these results indicate that the presence of OCT1 at the plasma membrane, rather than its expression levels, is related to better outcome of HCC patients treated with sorafenib.

Efficacy of Different Treatment Alternatives for Obesity Hypoventilation Syndrome. Pickwick Study.

RATIONALE: The incidence of obesity hypoventilation syndrome (OHS) may be increasing in parallel with the present obesity epidemic. Despite extensive noninvasive ventilation (NIV) and continuous positive airway pressure (CPAP) use in patients with OHS, information regarding efficacy is limited. OBJECTIVES: We performed a large, multicenter randomized controlled study to determine the comparative efficacy of NIV, CPAP, and lifestyle modification (control group) using daytime PaCO2 as the main outcome measure. METHODS: Sequentially screened patients with OHS with severe sleep apnea were randomized into the above-mentioned groups for a 2-month follow up. Arterial blood gas parameters, clinical symptoms, health-related quality-of-life assessments, polysomnography, spirometry, 6-minute-walk distance, dropouts, compliance, and side effects were evaluated. Statistical analysis was performed using intention-to-treat analysis, although adjustments for CPAP and NIV compliance were also analyzed. MEASUREMENTS AND MAIN RESULTS: In total, 351 patients were selected, and 221 were randomized. NIV yielded the greatest improvement in PaCO2 and bicarbonate, with significant differences relative to the control group but not relative to the CPAP group. In the CPAP group, PaCO2 improvement was significantly different than in the control group only after CPAP compliance adjustment. Additionally, clinical symptoms and polysomnographic parameters improved similarly with NIV and CPAP relative to the control. However, some health-related quality-of-life assessments, the spirometry, and 6-minute-walk distance results improved more with NIV than with CPAP. Dropouts were similar between groups, and compliance and secondary effects were similar between NIV and CPAP. CONCLUSIONS: NIV and CPAP were more effective than lifestyle modification in improving clinical symptoms and polysomnographic parameters, although NIV yielded better respiratory functional improvements than did CPAP. Long-term studies must demonstrate whether this functional improvement has relevant implications. Clinical trial registered with www.clinicaltrials.gov (NCT01405976).

Expression of SLC22A1 variants may affect the response of hepatocellular carcinoma and cholangiocarcinoma to sorafenib.

UNLABELLED: Reduced drug uptake is an important mechanism of chemoresistance. Down-regulation of SLC22A1 encoding the organic cation transporter-1 (OCT1) may affect the response of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CGC) to sorafenib, a cationic drug. Here we investigated whether SLC22A1 variants may contribute to sorafenib chemoresistance. Complete sequencing and selective variant identification were carried out to detect single nucleotide polymorphisms (SNPs) in SLC22A1 complementary DNA (cDNA). In HCC and CGC biopsies, in addition to previously described variants, two novel alternative spliced variants and three SNPs were identified. To study their functional consequences, these variants were mimicked by directed mutagenesis and expressed in HCC (Alexander and SK-Hep-1) and CGC (TFK1) cells. The two novel described variants, R61S fs*10 and C88A fs*16, encoded truncated proteins unable to reach the plasma membrane. Both variants abolished OCT1-mediated uptake of tetraethylammonium, a typical OCT1 substrate, and were not able to induce sorafenib sensitivity. In cells expressing functional OCT1 variants, OCT1 inhibition with quinine prevented sorafenib-induced toxicity. Expression of OCT1 variants in Xenopus laevis oocytes and determination of quinine-sensitive sorafenib uptake by high-performance liquid chromatography-dual mass spectrometry confirmed that OCT1 is able to transport sorafenib and that R61S fs*10 and C88A fs*16 abolish this ability. Screening of these SNPs in 23 HCC and 15 CGC biopsies revealed that R61S fs*10 was present in both HCC (17%) and CGC (13%), whereas C88A fs*16 was only found in HCC (17%). Considering all SLC22A1 variants, at least one inactivating SNP was found in 48% HCC and 40% CGC. CONCLUSION: Development of HCC and CGC is accompanied by the appearance of aberrant OCT1 variants that, together with decreased OCT1 expression, may dramatically affect the ability of sorafenib to reach active intracellular concentrations in these tumors.

Bile acids: chemistry, physiology, and pathophysiology.

The family of bile acids includes a group of molecular species of acidic steroids with very peculiar physical-chemical and biological characteristics. They are synthesized by the liver from cholesterol through several complementary pathways that are controlled by mechanisms involving fine-tuning by the levels of certain bile acid species. Although their best-known role is their participation in the digestion and absorption of fat, they also play an important role in several other physiological processes. Thus, genetic abnormalities accounting for alterations in their synthesis, biotransformation and/or transport may result in severe alterations, even leading to lethal situations for which the sole therapeutic option may be liver transplantation. Moreover, the increased levels of bile acids reached during cholestatic liver diseases are known to induce oxidative stress and apoptosis, resulting in damage to the liver parenchyma and, eventually, extrahepatic tissues. When this occurs during pregnancy, the outcome of gestation may be challenged. In contrast, the physical-chemical and biological properties of these compounds have been used as the bases for the development of drugs and as pharmaceutical tools for the delivery of active agents.

The antiviral activities of artemisinin and artesunate.

Traditional Chinese medicine commands a unique position among all traditional medicines because of its 5000 years of history. Our own interest in natural products from traditional Chinese medicine was triggered in the 1990s, by artemisinin-type sesquiterpene lactones from Artemisia annua L. As demonstrated in recent years, this class of compounds has activity against malaria, cancer cells, and schistosomiasis. Interestingly, the bioactivity of artemisinin and its semisynthetic derivative artesunate is even broader and includes the inhibition of certain viruses, such as human cytomegalovirus and other members of the Herpesviridae family (e.g., herpes simplex virus type 1 and Epstein-Barr virus), hepatitis B virus, hepatitis C virus, and bovine viral diarrhea virus. Analysis of the complete profile of the pharmacological activities and molecular modes of action of artemisinin and artesunate and their performance in clinical trials will further elucidate the full antimicrobial potential of these versatile pharmacological tools from nature.

Effect of cantharidin, cephalotaxine and homoharringtonine on "in vitro" models of hepatitis B virus (HBV) and bovine viral diarrhoea virus (BVDV) replication.

The effect as antiviral agents versus viral hepatitis B and C of three compounds purified from natural products commonly used as remedies in traditional Chinese medicine, cantharidin, cephalotaxine and homoharingtonine, was investigated. To assess the activity of these compounds against flavivirus, we used bovine viral diarrhoea virus (BVDV) as a surrogate for hepatitis C virus (HCV). Anti-BVDV activity was determined by reduction in BVDV-RNA production and protection of infected embryonic bovine trachea (EBTr) cells against the cytopathic effect of BVDV. The effect versus hepatitis B virus (HBV) was investigated by measuring HBsAg and HBV-DNA release from hepatoblastoma HepG2 2.2.15 cells infected with HBV. As positive control we used the standard anti-HBV and anti-HCV drugs, lamivudine and ribavirin, respectively. Up to 100 microM lamivudine and ribavirin did not induce cell toxicity, whereas they induced dose-dependent anti-HBV and anti-BVDV effects, respectively. In the same range, cantharidin, cephalotaxine and homoharringtonine induced toxicity in EBTr cells and had no protective effect against BVDV. In contrast, they were able to inhibit HBV production at concentrations 10- to 100-fold lower than those inducing cell toxicity, which suggests that they are useless for the treatment of infection by flaviviruses, but potentially useful in combined therapy against hepatitis B.

Antiviral effect of artemisinin from Artemisia annua against a model member of the Flaviviridae family, the bovine viral diarrhoea virus (BVDV).

The antiviral activity versus flaviviruses of artemisinin, a safe drug obtained from Artemisia annua and commonly used to treat malaria, has been investigated using as an IN VITRO model bovine epithelial cells from embryonic trachea (EBTr) infected with the cytopathic strain Oregon C24V, of bovine viral diarrhoea virus (BVDV), which is a member of the Flaviviridae family. Antiviral activity was estimated by the degree of protection against the cytopathic effect of BVDV on host cells and by the reduction in BVDV-RNA release to the culture medium. To induce an intermediate cytopathic effect in non-treated cells, EBTr cells were first exposed to BVDV for 48 h and then incubated with virus-free medium for 72 h. Ribavirin and artemisinin (up to 100 microM) induced no toxicity in host cells, whereas a slight degree of toxicity was observed for IFN-alpha at concentrations above 10 U/mL up to 100 U/mL. Treatment of infected cells with IFN-alpha, ribavirin and artemisinin markedly reduced BVDV-induced cell death. A combination of these drugs resulted in an additive protective effect. These drugs induced a significant reduction in the production/release of BVDV virions by infected EBTr cells; there was also an additive effect when combinations of them were assayed. These results suggest a potential usefulness of artemisinin in combination with current pharmacological therapy for the treatment of human and veterinary infections by flaviviruses.

Bioremediation by composting of heavy oil refinery sludge in semiarid conditions.

The present work attempts to ascertain the efficacy of low cost technology (in our case, composting) as a bioremediation technique for reducing the hydrocarbon content of oil refinery sludge with a large total hydrocarbon content (250-300 g kg(-1)), in semiarid conditions. The oil sludge was produced in a refinery sited in SE Spain The composting system designed, which involved open air piles turned periodically over a period of 3 months, proved to be inexpensive and reliable. The influence on hydrocarbon biodegradation of adding a bulking agent (wood shavings) and inoculation of the composting piles with pig slurry (a liquid organic fertiliser which adds nutrients and microbial biomass to the pile) was also studied. The most difficult part during the composting process was maintaining a suitable level of humidity in the piles. The most effective treatment was the one in which the bulking agent was added, where the initial hydrocarbon content was reduced by 60% in 3 months, compared with the 32% reduction achieved without the bulking agent. The introduction of the organic fertiliser did not significantly improve the degree of hydrocarbon degradation (56% hydrocarbon degraded). The composting process undoubtedly led to the biodegradation of toxic compounds, as was demonstrated by ecotoxicity tests using luminescent bacteria and tests on plants in Petri dishes.

Effect of artemisinin/artesunate as inhibitors of hepatitis B virus production in an "in vitro" replicative system.

The antiviral effect against hepatitis B virus (HBV) of artemisinin, its derivative artesunate and other compounds highly purified from traditional Chinese medicine remedies, were investigated. HBV production by permanently transfected HepG2 2.2.15 cells was determined by measuring the release of surface protein (HBsAg) and HBV-DNA after drug exposure (0.01-100 microM) for 21 days. The forms of HBV-DNA released were investigated by Southern-blotting. Neutral Red retention test was used to evaluate drug-induced toxicity on host cells. The compounds were classified according to their potential interest as follows: (i) none: they had no effect on viral production (daidzein, daidzin, isonardosinon, nardofuran, nardosinon, tetrahydronardosinon and quercetin); (ii) low: they were able to markedly reduce viral production, but also induced toxicity on host cells (berberine and tannic acid) or they had no toxic effect on host cells but only had a moderate ability to reduce viral production (curcumin, baicalein, baicalin, bufalin, diallyl disulphide, glycyrrhizic acid and puerarin); (iii) high: they induced strong inhibition of viral production at concentrations at which host cell viability was not affected (artemisinin and artesunate). Moreover, artesunate in conjunction with lamivudine had synergic anti-HBV effects, which warrants further evaluation of artemisinin/artesunate as antiviral agents against HBV infection.

Un caso de extrofia vesical / A case of vesical extrophia

El hallazgo de extrofia vesical en un recién nacido, constituye en la práctica urológica como pediátrica una alteración embriológica sumamente rara, pues la literatura cita una incidencia de 1 en 20.000 a 1 en 100.000, motivo por el cual se presenta este caso. Los autores presentan un caso de extrofia vesical, variedad completa en un recién nacido de sexo masculino. Se hace una revisión sobre las causas no encontrando etiología determinada, se comenta la frecuencia en nuestro medio-segundo caso en 32 años y primero de variedad completa-se describe la intervención quirúrgica y sus resultado para corregir esta alteración