Strain difference in transgene-induced tumorigenesis and suppressive effect of ionizing radiation

Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53^+/−, p53^−/−) and Hd-rR HNI hybrid (p53^+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53^+/− fish than in p53^−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.     

The effects of graphene nanostructures on mesenchymal stem cells

We report the effects of two-dimensional graphene nanostructures; graphene nano-onions (GNOs), graphene oxide nanoribbons (GONRs), and graphene oxide nanoplatelets (GONPs) on viability, and differentiation of human mesenchymal stem cells (MSCs). Cytotoxicity of GNOs, GONRs, and GONPs dispersed in distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)] (DSPE-PEG), on adipose derived mesenchymal stem cells (adMSCs), and bone marrow-derived mesenchymal stem cells (bmMSCs) was assessed by AlamarBlue and Calcein AM viability assays at concentrations ranging from 5 to 300 μg/ml for 24 or 72 h. Cytotoxicity of the 2D graphene nanostructures was found to be dose dependent, not time dependent, with concentrations less than 50 μg/ml showing no significant differences compared to untreated controls. Differentiation potential of adMSCs to adipocytes and osteoblasts, – characterized by Oil Red O staining and elution, alkaline phosphatase activity, calcium matrix deposition and Alizarin Red S staining – did not change significantly when treated with the three graphene nanoparticles at a low (10 μg/ml) and high (50 μg/ml) concentration for 24 h. Transmission electron microscopy (TEM) and confocal Raman spectroscopy indicated cellular uptake of only GNOs and GONPs. The results lay the foundation for the use of these nanoparticles at potentially safe doses as ex vivo labels for MSC-based imaging and therapy.     

Is This Phantom Pain?

Right upper quadrant abdominal pain may be due to many causes, and at times may give rise to diagnostic dilemma. We present here a young lady with biliary type of pain who was eventually found to have gall bladder agenesis with aerobilia, in the absence of prior biliary intervention.     

Synthetically important ring opening reactions by alkoxybenzenes and alkoxynaphthalenes

Alkoxybenzenes and alkoxynaphthalenes, as nucleophiles, have drawn great attention from organic chemists over the decades. Due to their high ring strain, those particular classes of molecules are often used in synthesis by utilizing their properties to undergo facile Friedel–Crafts alkylations. Different isomeric and low or densely substituted alkoxybenzenes are used for synthesis according to the structure of the target molecule. Isomeric methoxybenzenes, are the most commonly used molecule in this regard. This review aims to comprehensively cover the instances of different alkoxy-benzenes/naphthalenes used as nucleophiles for ring opening.

This concise review reports the ring opening functionalizations of small sized molecular rings with alkoxybenzenes/alkoxynaphthalenes in Friedel–Crafts fashion.     

An unusual case of vaccine-associated paralytic poliomyelitis

The present article reports a case involving an immunocompetent, previously well child who, despite two previous doses of inactivated poliovirus vaccine, developed severe flaccid paralysis consistent with polio after receiving oral polio vaccine.     

Middle-preserving pancreatectomy with reversed pancreaticogastrostomy: report of a case

Parenchyma-sparing pancreatic resections have been reported increasingly in recent years; however, for multifocal diseases involving the head and the tail of the pancreas, total pancreatectomy is still the preferred procedure. The possible consequence of this procedure is loss of normal pancreatic parenchyma, resulting in insufficiency of pancreatic exocrine and endocrine functions. Various types of limited resection have been introduced for isolated or multiple pancreatic lesions, depending on the location of the tumor. Even for multifocal diseases, if the pancreatic body is spared, a middle-preserving pancreatectomy (MPP) can be performed to assure maximal pancreatic function and uncompromised quality of life. Yet, few papers have introduced the feasibility of MPP for a better outcome. This report describes a new surgical technique for MPP using an alternative approach for the remnant pancreas anastomosis. We used this technique successfully to remove a bifocal neoplasm: adenocarcinoma of the distal bile duct and mucinous cyst adenoma in the tail of the pancreas.     

Malnutrition after pancreatic enzyme replacement therapy in chronic pancreatitis: Risk factors in real world practice

BackgroundRCTs that have shown improvement in coefficient of fat absorption with pancreatic enzyme replacement therapy (PERT) have seldom evaluated the impact on overall nutritional status.ObjectiveIn this study we evaluated factors responsible for persistence of malnutrition after PERT.MethodsIn this cross-sectional observational study, patients were enrolled based on predefined enrolment criteria. Patients were divided into those taking PERT regularly (Group A), irregularly (Group B) and not taking (Group C) for at least 3 months. Comprehensive evaluation of anthropometric measurements, nutritional assessment and dietary intake was performed. Malnutrition was measured using the Subjective Global Assessment (SGA) tool. Relationship between PERT status, dietary intake and nutritional status were evaluated using standard statistical methods. Logistic regression was performed to identify factors associated with persistence of malnutrition after PERT.Results377 patients with CP and 50 controls were included. 95 (25.2%) patients with CP were in Group A, 106 (28.1%) in Group B and 176 (46.7%) in Group C. 130 (34.5%) patients were malnourished, of which 76 (58.5%) were continuing PERT. There were no differences in clinical and biochemical nutritional markers between Groups A, B, and C. Calorie deficit and daily intake of calorie, protein, carbohydrates and fats were not different between those with and without PERT, but was significantly less in those with malnutrition. Logistic regression demonstrated inadequate dietary intake as independent risk factor for persistence of malnutrition.ConclusionEven though PERT is effective in PEI, comprehensive nutritional assessment, personalized nutritional counselling and therapy along with PERT is mandatory.