Multiple venous thrombosis caused by F9 gene duplication and treated with catheter-directed thrombolysis, AngioJet-assisted pharmaco-mechanical thromboectomy and manual aspiration thromboectomy.

Inferior vena cava thrombosis (IVCT) is rare. Thrombophilia is one of the important risk factors. It is also uncommon for gene mutations in F9 gene to cause thrombosis but not hemorrhage. A 35-year-old male patient was admitted to our department with left lower limb swelling without an obvious cause for 1 day. Through contrast-enhanced computed tomography and color Doppler ultrasound, he was found to have lower extremity deep vein thrombosis, IVCT and pulmonary embolism. Through whole-exome sequencing analysis, he was found to carry a 925.7 kb duplication (chrX:137939698-138865419, hg19) encompassing ATP11C , SRD5A1P1 , MCF2 , FGF13 and F9 genes. This duplication of F9 gene was not detected in his parents. Other thrombophilic genes defects were not found. The factor IX activities of this patient, his father and mother were 194, 70 and 148, respectively. He was treated with catheter-directed thrombolysis, AngioJet-assisted pharmaco-mechanical thromboectomy and manual aspiration thromboectomy. Complete recanalization of left femoral, iliac veins and inferior vena cava was achieved. F9 gene duplication is a rare mutation, which can induce multiple venous thrombosis through increasing the activity level of factor IX in plasma. IVCT is a serious type of venous thrombosis. Personalized intervention treatment plans should be developed based on the different clinical characteristics of each case to achieve a higher benefit-risk ratio.

The SNP rs460089 in the gene promoter of the drug transporter OCTN1 has prognostic value for treatment-free remission in chronic myeloid leukemia patients treated with imatinib.

Membrane transporters are important determinants of drug bioavailability. Their expression and activity affect the intracellular drug concentration in leukemic cells impacting response to therapy. Pharmacogenomics represents genetic markers that reflect allele arrangement of genes encoding drug transporters associated with treatment response. In previous work, we identified SNP rs460089 located in the promotor of SLC22A4 gene encoding imatinib transporter OCTN1 as influential on response of patients with chronic myeloid leukemia treated with imatinib. Patients with rs460089-GC pharmacogenotype had significantly superior response to first-line imatinib treatment compared to patients with rs460089-GG. This study investigated whether pharmacogenotypes of rs460089 are associated with sustainability of treatment-free remission (TFR) in patients from the EUROpean Stop Kinase Inhibitor (EURO-SKI) trial. In the learning sample, 176 patients showed a significantly higher 6-month probability of molecular relapse free survival (MRFS) in patients with GC genotype (73%, 95% CI: 60-82%) compared to patients with GG (51%, 95% CI: 41-61%). Also over time, patients with GC genotype had significantly higher MRFS probabilities compared with patients with GG (HR: 0.474, 95% CI: 0.280-0.802, p = 0.0054). Both results were validated with data on 93 patients from the Polish STOP imatinib study. In multiple regression models, in addition to the investigated genotype, duration of TKI therapy (EURO-SKI trial) and duration of deep molecular response (Polish study) were identified as independent prognostic factors. The SNP rs460089 was found as an independent predictor of TFR.

IFNγ, TNFα polymorphisms and IFNγ serum levels are associated with the clearance of drug-resistant P. falciparum in Malian children.

Host immunity has been suggested to clear drug-resistant parasites in malaria-endemic settings. However, the immunogenetic mechanisms involved in parasite clearance are poorly understood. Characterizing the host's immunity and genes involved in controlling the parasitic infection can inform the development of blood-stage malaria vaccines. This study investigates host regulatory cytokines and immunogenomic factors associated with the clearance of Plasmodium falciparum carrying a chloroquine resistance genotype. Biological samples from participants of previous drug efficacy trials conducted in two Malian localities were retrieved. The P. falciparum chloroquine resistance transporter (Pfcrt) gene was genotyped using parasite DNA. Children carrying parasites with the mutant allele (Pfcrt-76T) were classified based on their ability to clear their parasites. The levels of the different cytokines were measured in serum. The polymorphisms of specific human genes involved in malaria susceptibility were genotyped using human DNA. The prevalence of the Pfcrt-76T was significantly higher in Kolle than in Bandiagara (81.6 % vs 38.6 %, p < 10-6). The prevalence of children who cleared their mutant parasites was significantly higher in Bandiagara than in Kolle (82.2 % vs 67.4 %, p < 0.05). The genotyping of host genes revealed that IFN-γ -874 T and TNF-α -308A alleles were positively associated with parasite clearance. Cytokine profiling revealed that IFN-γ level was positively associated with parasite clearance (p = 0.04). This study highlights the role of host's immunity and immunogenetic factors to clear resistant parasites, suggesting further characterization of these polymorphisms may help to develop novel approaches to antiparasitic treatment strategies.

A combined ligand and target-based virtual screening strategy to repurpose drugs as putrescine uptake inhibitors with trypanocidal activity.

Chagas disease, also known as American trypanosomiasis, is a neglected tropical disease caused by the protozoa Trypanosoma cruzi, affecting nearly 7 million people only in the Americas. Polyamines are essential compounds for parasite growth, survival, and differentiation. However, because trypanosomatids are auxotrophic for polyamines, they must be obtained from the host by specific transporters. In this investigation, an ensemble of QSAR classifiers able to identify polyamine analogs with trypanocidal activity was developed. Then, a multi-template homology model of the dimeric polyamine transporter of T. cruzi, TcPAT12, was created with Rosetta, and then refined by enhanced sampling molecular dynamics simulations. Using representative snapshots extracted from the trajectory, a docking model able to discriminate between active and inactive compounds was developed and validated. Both models were applied in a parallel virtual screening campaign to repurpose known drugs as anti-trypanosomal compounds inhibiting polyamine transport in T. cruzi. Montelukast, Quinestrol, Danazol, and Dutasteride were selected for in vitro testing, and all of them inhibited putrescine uptake in biochemical assays, confirming the predictive ability of the computational models. Furthermore, all the confirmed hits proved to inhibit epimastigote proliferation, and Quinestrol and Danazol were able to inhibit, in the low micromolar range, the viability of trypomastigotes and the intracellular growth of amastigotes.

Molecular characterization of the severe falciparum malaria with typhoid co-infection: A case report.

Malaria and typhoid co-infections can be a serious public health issue in tropical countries leading to incorrect diagnosis due to overlapping clinical presentations of malaria and typhoid and hence, causing a delay in implementing the appropriate treatment regimen for these concurrent infections. This study reports a case of six-year-old female child co-infected with severe malaria (Plasmodium falciparum) and typhoid (Salmonella typhi) diagnosed by rapid malaria antigen test (RMAT) and blood culture respectively. Further, analysis of the chloroquine resistance gene Pfcrt for the falciparum demonstrated the presence of K76T mutant allele in pfcrt gene with high IC50 (150nM) for chloroquine (CQ) drug. The present case highlights the significance of timely identification and treatment of co-infections and also provides information about the circulating P. falciparum clinical strains.

Biotin-Responsive Basal Ganglia Disease: Treatable Metabolic Disorder with SLC19A3 Mutation Presenting as Rapidly Progressive Dementia.

Background and Aims: Biotin-thiamine-responsive basal ganglia disease (BTBGD) is an autosomal recessive disorder due to mutations in the SLC19A3-gene, typically seen in early childhood. Materials and Methods: We report a 49-year-old lady presenting with rapidly progressive cognitive impairment, seizures, hypersomnolence, ataxia, and generalized dystonia of 3 weeks duration. The magnetic resonance imaging (MRI) of the brain revealed T2-hyperintensities in the basal ganglia, thalamus, cortical, subcortical regions with striatal necrosis suggestive of BTBGD that was confirmed by genetic analysis. She was treated with thiamine and biotin following which there was significant clinical and MRI improvement. Conclusions: BTBGD requires a high index of suspicion in any patient presenting with unexplained rapidly progressive dementia. High doses of biotin and thiamine are the mainstay of the treatment to achieve a favorable outcome.

Basal Ganglia Disease Mimicking Acute Encephalitis Syndrome Among Infants of Bodo Tribe, Assam.

We conducted a review of hospital records of infants with acute encephalitis syndrome with bilateral symmetrical basal ganglia infarcts, between 2011-2015, at a single center in Assam. Thiamine (as part of multivitamin injection) was used in the treatment of 23 infants and not used in 27; Only 1 (3.7%) infant died in the former group and 20 infants (86.9%) died in the latter [RR (95% CI) 0.04 (0.006,0.29); P<0.001). Two infants on follow-up had normal development, both in the thiamine group. The study suggests the possibility of subclinical thiamine deficiency, mitochondrial diseases, or SLC19A3 gene mutation in this population.

[Progression on Multifunctional Nanoparticles Interfering with Cell Membrane Transporters-associated Drug Resistance].

Multi-drug resistance(MDR)refers to the loss of sensitivity of tumor cells to traditional chemotherapeutics agents under the mediation of various mechanisms,resulting in the reduction of chemotherapy efficacy.Current studies suggest that a variety of factors,including cell membrane transporter-mediated efflux of anti-tumor drugs,special microenvironment in tumor tissue,DNA self-repair and anti-apoptotic process,and epithelial-mesenchymal cell transformation,may contribute to the formation of MDR.Cell membrane transporter-mediated drug efflux refers to an increase in the amount of anti-tumor drug pumped out of the cell through the up-regulation of the ATP-binding cassette transporter on tumor cell membrane,which reduces the concentration of the drug in the cell,thus forming MDR.An effective method to inhibit the efflux pump caused by overexpression of membrane transporters plays an important role in overcoming MDR.As a promising drug delivery system,multifunctional nanoparticles have demonstrated many advantages in antitumor therapy.Meanwhile,nanoparticles with tailored design are capable of overcoming MDR when combined with a variety of strategies.This paper described in detail the studies relevant to the use of multifunctional nano-sized drug delivery system combined with different strategies,such as co-delivery of agents,external responsiveness or target modification for intervention with efflux pump in order to reverse MDR.This paper provides reference for the development of nano-sized drug delivery system and the formulation of reversal strategy in the future.

Subpatent Plasmodium with mutant pfmdr1, pfcrt, and pvmdr1 alleles from endemic provinces in Mindanao, the Philippines: implications for local malaria elimination.

OBJECTIVES: This study was performed to identify and characterize circulating Plasmodium species in three provinces of Mindanao approaching malaria elimination. METHODS: Rapid diagnostic tests (RDT), microscopic examination, and PCR were used to detect malaria parasites. PCR-positive isolates were genotyped for polymorphisms in loci of interest. RESULTS: A total of 2639 participants were surveyed in Mindanao between 2010 and 2013. Malaria prevalence by PCR was 3.8% (95% confidence interval (CI): 2.7-5.2%) in Sarangani, 10% (95% CI: 7.7-12.7%) in South Cotabato, and 4.2% (95% CI: 3.2-5.6%) in Tawi-Tawi. P. falciparum and P. vivax were identified in all three provinces, and there was one case of P. malariae in South Cotabato. RDT was inferior to PCR for detecting asymptomatic P. falciparum and P. vivax. In Tawi-Tawi, microscopy failed to identify 46 PCR-positive malaria infections. The presence of pfcrt haplotypes CVMNK, CVIET, and SMNT (codons 72-76), pfmdr1 haplotype NFSND (codons 86, 184, 1034, 1042, 1246), and pvmdr1 haplotype NFL (codons 91, 976, 1076) was confirmed in Mindanao. CONCLUSIONS: Asymptomatic Plasmodium infections persisted in local communities between 2010 and 2013. PCR successfully identified subpatent malaria infections, and can better characterize malaria epidemiology in communities seeking malaria control and elimination at the local level.

Progression on Multifunctional Nanoparticles Interfering with Cell Membrane Transporters-associated Drug Resistance / 中国医学科学院学报

Multi-drug resistance(MDR)refers to the loss of sensitivity of tumor cells to traditional chemotherapeutics agents under the mediation of various mechanisms,resulting in the reduction of chemotherapy efficacy.Current studies suggest that a variety of factors,including cell membrane transporter-mediated efflux of anti-tumor drugs,special microenvironment in tumor tissue,DNA self-repair and anti-apoptotic process,and epithelial-mesenchymal cell transformation,may contribute to the formation of MDR.Cell membrane transporter-mediated drug efflux refers to an increase in the amount of anti-tumor drug pumped out of the cell through the up-regulation of the ATP-binding cassette transporter on tumor cell membrane,which reduces the concentration of the drug in the cell,thus forming MDR.An effective method to inhibit the efflux pump caused by overexpression of membrane transporters plays an important role in overcoming MDR.As a promising drug delivery system,multifunctional nanoparticles have demonstrated many advantages in antitumor therapy.Meanwhile,nanoparticles with tailored design are capable of overcoming MDR when combined with a variety of strategies.This paper described in detail the studies relevant to the use of multifunctional nano-sized drug delivery system combined with different strategies,such as co-delivery of agents,external responsiveness or target modification for intervention with efflux pump in order to reverse MDR.This paper provides reference for the development of nano-sized drug delivery system and the formulation of reversal strategy in the future.

Structural insights into the architecture and membrane interactions of the conserved COMMD proteins.

The COMMD proteins are a conserved family of proteins with central roles in intracellular membrane trafficking and transcription. They form oligomeric complexes with each other and act as components of a larger assembly called the CCC complex, which is localized to endosomal compartments and mediates the transport of several transmembrane cargos. How these complexes are formed however is completely unknown. Here, we have systematically characterised the interactions between human COMMD proteins, and determined structures of COMMD proteins using X-ray crystallography and X-ray scattering to provide insights into the underlying mechanisms of homo- and heteromeric assembly. All COMMD proteins possess an α-helical N-terminal domain, and a highly conserved C-terminal domain that forms a tightly interlocked dimeric structure responsible for COMMD-COMMD interactions. The COMM domains also bind directly to components of CCC and mediate non-specific membrane association. Overall these studies show that COMMD proteins function as obligatory dimers with conserved domain architectures.

Pitpnc1a Regulates Zebrafish Sleep and Wake Behavior through Modulation of Insulin-like Growth Factor Signaling.

The lipid transporters of the phosphatidylinositol transfer protein (PITP) family dictate phosphoinositide compartmentalization, and specific phosphoinositides play crucial roles in signaling cascades, membrane traffic, ion channel regulation, and actin dynamics. Although PITPs are enriched in the brain, their physiological functions in neuronal signaling pathways in vivo remain ill defined. We describe a CRISPR/Cas9-generated zebrafish mutant in a brain-specific, conserved class II PITP member, pitpnc1a. Zebrafish pitpnc1a mutants are healthy but display widespread aberrant neuronal activity and increased wakefulness across the day-night cycle. The loss of Pitpnc1a increases insulin-like growth factor (IGF) signaling in the brain, and inhibition of IGF pathways is sufficient to rescue both neuronal and behavioral hyperactivity in pitpnc1a mutants. We propose that Pitpnc1a-expressing neurons alter behavior via modification of neuro-modulatory IGF that acts on downstream wake-promoting circuits.

Proapoptotic action of p53-Tom5 in p53-resistant A549 human non-small cell lung cancer cells through direct mitochondrial dysfunction.

Transcription-dependent apoptosis triggered by p53 hardly occurs in alternative reading frame (ARF)-null cancer cells. Loss of ARF leads to hyperactivation of murine double minute 2 (MDM2), resulting in the degradation of p53. In the present study, A549 (ARF-null) human non-small lung cancer cells were transfected with a plasmid DNA encoding human wild-type p53 and the mitochondrial transmembrane domain of Tom5 (p53-Tom5) for delivering p53 to mitochondria. As a result, p53-Tom5 exclusively localized at mitochondria in A549 cells and suppressed the proliferation of them, whereas wild-type p53 did not. In addition, mitochondrial dysfunction and release of cytochrome c were induced by p53-Tom5 in A549 cells. These data suggest that p53-Tom5 suppressed the proliferation of A549 cells through direct mitochondrial dysfunction.

Transport characteristics of a novel peptide transporter 1 substrate, antihypotensive drug midodrine, and its amino acid derivatives.

Midodrine is an oral drug for orthostatic hypotension. This drug is almost completely absorbed after oral administration and converted into its active form, 1-(2',5'-dimethoxyphenyl)-2-aminoethanol) (DMAE), by the cleavage of a glycine residue. The intestinal H+-coupled peptide transporter 1 (PEPT1) transports various peptide-like drugs and has been used as a target molecule for improving the intestinal absorption of poorly absorbed drugs through amino acid modifications. Because midodrine meets these requirements, we examined whether midodrine can be a substrate for PEPT1. The uptake of midodrine, but not DMAE, was markedly increased in PEPT1-expressing oocytes compared with water-injected oocytes. Midodrine uptake by Caco-2 cells was saturable and was inhibited by various PEPT1 substrates. Midodrine absorption from the rat intestine was very rapid and was significantly inhibited by the high-affinity PEPT1 substrate cyclacillin, assessed by the alteration of the area under the blood concentration-time curve for 30 min and the maximal concentration. Some amino acid derivatives of DMAE were transported by PEPT1, and their transport was dependent on the amino acids modified. In contrast to neutral substrates, cationic midodrine was taken up extensively at alkaline pH, and this pH profile was reproduced by a 14-state model of PEPT1, which we recently reported. These findings indicate that PEPT1 can transport midodrine and contributes to the high bioavailability of this drug and that Gly modification of DMAE is desirable for a prodrug of DMAE.

The emerging functions of UCP2 in health, disease, and therapeutics.

The uncoupling proteins (UCPs) are attracting an increased interest as potential therapeutic targets in a number of important diseases. UCP2 is expressed in several tissues, but its physiological functions as well as potential therapeutic applications are still unclear. Unlike UCP1, UCP2 does not seem to be important to thermogenesis or weight control, but appears to have an important role in the regulation of production of reactive oxygen species, inhibition of inflammation, and inhibition of cell death. These are central features in, for example, neurodegenerative and cardiovascular disease, and experimental evidence suggests that an increased expression and activity of UCP2 in models of these diseases has a beneficial effect on disease progression, implicating a potential therapeutic role for UCP2. UCP2 has an important role in the pathogenesis of type 2 diabetes by inhibiting insulin secretion in islet beta cells. At the same time, type 2 diabetes is associated with increased risk of cardiovascular disease and atherosclerosis where an increased expression of UCP2 appears to be beneficial. This illustrates that therapeutic applications involving UCP2 likely will have to regulate expression and activity in a tissue-specific manner.

The impact of efflux transporters in the brain on the development of drugs for CNS disorders.

The development of drugs to treat disorders of the CNS requires consideration of achievable brain concentrations. Factors that influence the brain concentrations of drugs include the rate of transport into the brain across the blood-brain barrier (BBB), metabolic stability of the drug, and active transport out of the brain by efflux mechanisms. To date, three classes of transporter have been implicated in the efflux of drugs from the brain: multidrug resistance transporters, monocarboxylic acid transporters, and organic ion transporters. Each of the three classes comprises multiple transporters, each of which has multiple substrates, and the combined substrate profile of these transporters includes a large number of commonly used drugs. This system of transporters may therefore provide a mechanism through which the penetration of CNS-targeted drugs into the brain is effectively minimised. The action of these efflux transporters at the BBB may be reflected in the clinic as the minimal effectiveness of drugs targeted at CNS disorders, including HIV dementia, epilepsy, CNS-based pain, meningitis and brain cancers. Therefore, modulation of these efflux transporters by design of inhibitors and/or design of compounds that have minimal affinity for these transporters may well enhance the treatment of intractable CNS disorders.