Design of a DOPC-MoS2/AuNP hybrid as an organic bed with higher amplification for miR detection in electrochemical biosensors.

The liposome-based biosensors are used for detection of nucleic acids and proteins as organic beds which are biocompatible tools for point of care tests, but their lack of sensitivity has been challenging. Therefore, designing a proper strategy is vital to increase the sensitivity of the target in diagnostic tests. In this study, for the first time, we use a combination of cationic DOPC liposome (dioleoylphosphatidylcholine) with MoS2 to enhance the sensitivity of liposomal sensors clearly. The electrochemical measurements are performed between potentials at - 0.4 V and + 0.4 V with 1 mM [Fe(CN)6]-3/-4. At first, we construct the DOPC/MoS2 hybrid (as a mineral/organic bed) to promote higher electrochemical behavior than DOPC liposome (as organic bed). In this research, adding AuNP can cause attachment with both the DOPC and MoS2. Therefore, the electrochemical reactions are enhanced accordingly to provide more positions for attaching the probes on the AuNP. So our DOPC-MoS2/AuNP hybrid can detect miR-21 with high sensitivity (LOD = 10 aM) because of attachment of miR-21 to MoS2/AuNP in addition to DOPC/AuNP. This sensor has also high specificity and repeatability as a biocompatible sensor, which can be used in point of care tests and transduction instruments.

Antimicrobial stewardship program (ASP): an effective implementing technique for the therapy efficiency of meropenem and vancomycin antibiotics in Iranian pediatric patients.

BACKGROUND: Antimicrobial stewardship program (ASP) is a distinguished method to improve the prescription and efficacy of antibiotics. AIM: The efficacy of ASP and conventional methods was compared to measure the effectiveness of meropenem (MPM) and vancomycin (VMN) antibiotics in pediatric patients. DESIGN: In an interventional quasi-experimental study, 135 children admitted in Children's Hospital affiliated to University of Medical Sciences in time periods of 2014-2015 and 2015-2016 were assessed. METHODS: The conventional and ASP methods in 2014-2015 and 2015-2016 were respectively utilized to provide the best antimicrobial therapy of MPM and VMN antibiotics in patient children. The data of mortality rate (MR), antibiotic prescription (AP), antibiotic dose (ADe), antibiotic duration (ADn), length of hospital stay (LOHS), and blood cultures (BCs) were compared across the years using the Chi square, independent t test, and Fisher's exact test. RESULTS: The levels of MR, AP, ADe, ADn, LOHS, and positive BCs using the ASP method in 2015-2016 were significantly lower those of in 2014-2015 using the conventional one (p < 0.05). CONCLUSIONS: The ASP method versus conventional one with a better efficacy can be employed as an antibiotic administration guide for MPM and VMN in the therapy of patients in community-based hospitals.

Hereditary Spherocytosis Unmasked by Human Parvovirus B19 Induced Aplastic Crisis in a Family.

Human parvovirus (HPV) B19 induced aplastic crisis in a family leading to the diagnosis of hereditary spherocytosis (HS) is a very rare condition being barely reported in the literature. We herein report a 4-year-old girl, her brother, and their mother who all presented with progressive pallor and jaundice after a febrile illness. The HPV B19 was diagnosed using polymerase chain reaction (PCR) and positive serology for specific anti-HPV B19 IgM. They were further diagnosed with having HS. The clinical importance of this report is that in the case of an abrupt onset of unexplained severe anemia and jaundice, one should consider underlying hemolytic anemias mostly hereditary spherocytosis complicated by HPV B19 aplastic crisis. Herein, we report the occurrence of this condition, simultaneously in three members of a family. The distinguished feature of this report is that all affected family members developed some degrees of transient pancytopenia, not only anemia, all simultaneously in the course of their disease.

Infantile splenorenopancreatic mucormycosis complicating neuroblastoma.

Herein is described the first case of an infant with neuroblastoma who developed isolated splenorenopancreatic mucormycosis. An 18-month-old boy with neuroblastoma who was on intensive chemotherapy was admitted with febrile neutropenia. On abdominal computed tomography, multiple hypodense lesions in the spleen with invasion to the upper pole of the left kidney were demonstrated. Enlargement of splenic lesions with a complete hypoechoic pattern replacing the whole spleen, consistent with splenic abscess were observed on serial ultrasound. On splenectomy the resected spleen appeared to be severely fragmented and necrotic. On pathology, massive infiltration of broad, non-septate hyphal fragments identified as Mucor with invasion to all blood vessels was seen. Histologically, a piece of the tail of the pancreas also showed involvement by the filamentous Mucor. The present case highlights the necessity of high index of suspicion in susceptible patients, early diagnosis and appropriate management in order to minimize the mortality rate.

Dual electrochemical sensing of spiked virus and SARS-CoV-2 using natural bed-receptor (MV-gal1).

It has been necessary to use methods that can detect the specificity of a virus during virus screening. In this study, we use a dual platform to identify any spiked virus and specific SARS-CoV-2 antigen, sequentially. We introduce a natural bed-receptor surface as Microparticle Vesicle-Galactins1 (MV-gal1) with the ability of glycan binding to screen every spiked virus. MV are the native vesicles which may have the gal-1 receptor. Gal-1 is the one of lectin receptor which can bind to glycan. After dropping the MV-gal1 on the SCPE/GNP, the sensor is turned on due to the increased electrochemical exchange with [Fe(CN)6]-3/-4 probe. Dropping the viral particles of SARS-CoV-2 cause to turn off the sensor with covering the sugar bond (early screening). Then, with the addition of Au/Antibody-SARS-CoV-2 on the MV-gal1@SARS-CoV-2 Antigen, the sensor is turned on again due to the electrochemical amplifier of AuNP (specific detection).For the first time, our sensor has the capacity of screening of any spike virus, and the specific detection of COVID-19 (LOD: 4.57 × 102 copies/mL) by using the natural bed-receptor and a specific antibody in the point of care test.

Different liposome patterns to detection of acute leukemia based on electrochemical cell sensor.

Leukemia is the worst type of malignancy in children which its proper diagnosis can be used in the treatment. We design the turn-off sensor by using the different electrochemical patterns of liposomes to the detection of acute lymphoblastic leukemia cells. Our design is first sandwiched by lectin liposome which increases the electrochemical exchange on the electrode. With the addition of Molt-4 cells, the bonding connection between the n-glycan and lectin can also increase the electrochemical exchange with the high detection cells. Subsequently, the addition of boronic acid liposomes decreases the resistance due to covering glycosylation bond and the sensor is turn-off. But stable and specific binding with the sialic acid causes the higher detection of Molt-4 cells. The electrochemical measurements are performed between the potentials at -0.4 V and +0.4 V with 1 mM [Fe(CN)6] -3/-4. So, for the first time, we designed a cells sensor based on the different patterns of liposomes to screening the N-glycan cells, which can be used in the point of care tests with higher sensitivity.

Haemorrhagic cystitis due to BK virus in a child with ALL on standard chemotherapy without stem cell transplant.

The BK virus (BKV) is a nonenveloped double-stranded DNA virus of the polyomavirus family that primarily affects immunocompromised people. BKV infects humans at an early age. Initial infections with BKV are mainly asymptomatic and usually remain latent in the brain, peripheral blood, kidneys, and urothelium. Following the primary infection, viruses persist indefinitely as 'latent' infections of the kidney and urinary system because the virus is urotheliotropic. Reactivation of the virus infections occurs in individuals with severe immunosuppression states such as kidney and stem cell transplantation and rarely in pregnancy. In this line, BKV has been implicated as a common cause of late-onset haemorrhagic cystitis (HC) in patients who have undergone stem cell transplantation. In contrast, reports of BKV-associated diseases in nontransplant paediatric patients are almost exclusively in patients with human immunodeficiency virus infection. Herein, we report the first case of a child with acute lymphoblastic leukaemia who developed BKV-associated HC without receiving stem cell transplantation while on standard maintenance chemotherapy.

Clear cell sarcoma of the kidney misdiagnosed as mesoblastic nephroma: a case report and review of the literature.

Clear cell sarcoma of the kidney (CCSK) is a rare renal neoplasm of paediatrics, making up about 3% of all renal tumours in paediatrics, with a high tendency for developing bone metastasis. A seven year-old boy was referred to our clinic with two firm, large masses over the manubrium of the sternum and right frontal area, which pathologically were confirmed as a metastatic CCSK. The patient had a history of a renal mass three years earlier, for which radical nephrectomy had been performed, and histopathologic diagnosis was compatible with mesoblastic nephroma. Thus, no further investigation and therapy had been applied for the patient. CCSK is a rare but malignant and aggressive paediatric renal tumour, with a high tendency for developing distant bone metastases, leading to its poor prognosis. CCSK could be misdiagnosed as several other renal tumours such as mesoblastic nephroma, and thus CCSK should be taken carefully into consideration in the diagnosis of renal tumours.