Covalently modified halloysite clay nanotubes: synthesis, properties, biological and medical applications.

Halloysite (HNT) is a promising natural nanosized tubular clay mineral that has many important uses in different industrial fields. It is naturally occurring, biocompatible, and available in thousands of tons at low cost. As a consequence of a hollow cavity, HNT is mainly used as nanocontainer for the controlled release of several chemicals. Chemical modification of both surfaces (inner lumen and outer surface) is a strategy to tune the nanotube's properties. Specifically, chemical modification of HNT surfaces generates a nanoarchitecture with targeted affinity through outer surface functionalization and drug transport ability from functionalization of the nanotube lumen. The primary focus of this review is the research of modified halloysite nanotubes and their applications in biological and medical fields.

Correction: Covalently modified halloysite clay nanotubes: synthesis, properties, biological and medical applications.

Correction for 'Covalently modified halloysite clay nanotubes: synthesis, properties, biological and medical applications' by M. Massaro et al., J. Mater. Chem. B, 2017, 5, 2867-2882.

Direct chemical grafted curcumin on halloysite nanotubes as dual-responsive prodrug for pharmacological applications.

Covalently functionalized halloysite nanotubes (HNTs) were successfully employed as dual-responsive nanocarriers for curcumin (Cur). Particularly, we synthesized HNT-Cur prodrug with a controlled curcumin release on dependence of both intracellular glutathione (GSH) and pH conditions. In order to obtain HNT-Cur produgs, halloysite was firstly functionalized with cysteamine through disulphide linkage. Afterwards, curcumin molecules were chemically conjugated to the amino end groups of halloysite via Schiff's base formation. The successful functionalization of halloysite was proved by thermogravimetric analysis, FT-IR spectroscopy, dynamic light scattering and scanning electron microscopy. Experimental data confirmed the presence of curcumin on HNT external surface. Moreover, we investigated the kinetics of curcumin release by UV-vis spectroscopy, which highlighted that HNT-Cur prodrug possesses dual stimuli-responsive ability upon exposure to GSH-rich or acidic environment. In vitro antiproliferative and antioxidant properties of HNT-Cur prodrug were studied with the aim to explore their potential applications in pharmaceutics. This work puts forward an efficient strategy to prepare halloysite based nanocarriers with controlled drug delivery capacity through direct chemical grafting with stimuli-responsive linkage.

Multicavity halloysite-amphiphilic cyclodextrin hybrids for co-delivery of natural drugs into thyroid cancer cells.

Multicavity halloysite nanotube materials were employed as simultaneous carriers for two different natural drugs, silibinin and quercetin, at 6.1% and 2.2% drug loadings, respectively. The materials were obtained by grafting functionalized amphiphilic cyclodextrin onto the HNT external surface. The new materials were characterized by FT-IR spectroscopy, SEM, thermogravimetry, turbidimetry, dynamic light scattering and ζ-potential techniques. The interaction of the two molecules with the carrier was studied by HPLC measurements and fluorescence spectroscopy, respectively. The release of the drugs from HNT-amphiphilic cyclodextrin, at two different pH values, was also investigated by means of UV-vis spectroscopy. Biological assays showed that the new complex exhibits anti-proliferative activity against human anaplastic thyroid cancer cell lines 8505C. Furthermore, fluorescence microscopy was used to evaluate whether the carrier was uptaken into 8505C thyroid cancer cell lines. The successful results revealed that the synthesized multicavity system is a material of suitable size to transport drugs into living cells.

Characterization and predicted role of the microRNA expression profile in amnion from obese pregnant women.

Maternal obesity and nutrient excess in utero increase the risk of future metabolic diseases. The mechanisms underlying this process are poorly understood, but probably include genetic, epigenetic alterations and changes in fetal nutrient supply. We have studied the microRNA (miRNA) expression profile in amnion from obese and control women at delivery to investigate if a specific miRNA signature is associated with obesity. The expression profile of 365 human miRNAs was evaluated with the TaqMan Array in amnion from 10 obese and 5 control (prepregnancy body mass index (BMI) >30 and <25 kg m(-2), respectively) women at delivery. Target genes and miRNA-regulated pathways were predicted by bioinformatics. Anthropometric and biochemical parameters were also measured in mothers and newborns. Seven miRNAs were expressed only in obese women (miR-422b, miR-219, miR-575, miR-523, miR-579, miR-618 and miR-659), whereas 13 miRNAs were expressed at a higher level and 12 miRNAs at a lower level in obese women than in controls. MicroRNAs significantly downregulated the neurotrophin, cancer/ErbB, mammalian target of rapamycin, insulin, adipocytokine, actin cytoskeleton and mitogen-activated protein kinase signaling pathways. In conclusion, we show that the miRNA profile is altered in amnion during obesity and hypothesize that this could affect pathways important for placental growth and function, thereby contributing to an increase in the newborn's risk of future metabolic diseases.

Functionalized halloysite multivalent glycocluster as a new drug delivery system.

A new design for halloysite nanotube materials was obtained by grafting chemically modified cyclodextrin units onto the nanotube surface. In particular, grafted cyclodextrins were decorated with thiosaccharide pendants, in order to mimic the well-known binding of sugars to proteins and the glyco-cluster effect occurring during cellular recognition events. The obtained materials were characterized by using a combination of varied techniques (FT-IR spectroscopy, thermogravimetric analysis, scanning electron microscopy, dynamic light scattering, turbidimetry), and their potential drug-delivery abilities were tested by studying their interactions with the common naturally occurring anticancer agent curcumin. A suitable model describing the interaction between our materials and curcumin is proposed.

Miniaturized flow cytometry-based BCR-ABL immunoassay in detecting leptomeningeal disease.

Despite central nervous system (CNS) prophylactic programs limit leptomeningeal involvement in acute lymphoblastic leukemia (ALL), it can still occur in a restricted percentage of cases. The exact risk rate remains still unknown, and several factors are associated with an increased probability to develop CNS involvement. Among them, Philadelphia (Ph)-positive genotype seems to play a relevant role. Recently, a flow cytometric assay to detect BCR-ABL protein has been developed, but little is known about its possible employment in leptomeningeal disease. Here, we show the miniaturized application of the original assay for BCR-ABL oncoprotein detection in cerebrospinal fluid (CSF) samples.

Carotid intima-media thickness and liver histology in hemodialysis patients with nonalcoholic Fatty liver disease.

The prevalence of atherosclerotic cardiovascular disease in chronic hemodialysis (HD) patients has been demonstrated to be higher than in healthy people. Severe liver fibrosis is strongly associated with early carotid atherosclerosis and it might reduce the survival of patients who undergo both renal replacement therapy and transplantation. We wanted to assess whether nonalcoholic fatty liver disease (NAFLD) was associated with altered intima-media thickness (IMT) in HD patients as an independent marker of subclinical atherosclerosis. We enrolled 42 patients undergoing HD and 48 patients with normal renal function, all of them with high levels of aminotransferases and an ultrasonographic diagnosis of liver steatosis. The control group consisted of 60 healthy subjects. Laboratory tests for inflammatory and oxidative markers, ultrasonographic liver evaluation, carotid IMT measurement, and liver biopsy were performed. Different degrees of fibrosis were detected in our study cohort. Worse liver histopathological scores and higher plasmatic levels of C-reactive protein, reactive oxygen species, and vascular cell adhesion molecule-1 were found in HD patients. Carotid IMT was significantly higher (p < 0.005) in patients with histological steatosis. HD patients may develop active and progressive chronic hepatitis faster than patients with normal renal function and the thickness of their carotid intima-media might be markedly increased. These two conditions seem to be independent on classical risk factors and on metabolic syndrome. They might be related to the high levels of oxidants and to the inflammatory state, which are typical of patients undergoing HD. Independently related with the traditional risk factors for cardiovascular disease, nonspecific inflammation and oxide-reductive imbalance may play an important role in the progression of NAFLD and atherosclerotic disease in HD patients.

Polychromatic flow cytometry analysis of CD34+ hematopoietic stem cells in cryopreserved early preterm human cord blood samples.

During the last decades, extended characterizations were performed of human full-term cord blood (hTCB) cells, but little information is available on human early preterm cord blood (hEPCB) hematopoietic stem cells (HSCs). In our study, we analyzed by flow cytometry 19 hEPCB and 17 hTCB samples. First, we observed that the percentage of CD34(Pos)CD45(Dim) cells was higher in hEPCB compared with hTCB and that it decreased during 16th-20th week of pregnancy. Within the CD34(Pos)CD45(Dim) population, we examined the expression of CD29, CD31, CD38, CD90, CD117, CD133, CD135, CD200, CD243, and CD338. We found that CD135 intensity and CD243(Pos) cells percentage were lower in hEPCB compared with hTCB. As to CD38, we observed that hEPCB samples were richer in undifferentiated CD34(Pos)CD45(Dim)CD38(Neg) HSCs compared with hTCB counterparts. We also compared the expression of the above-mentioned molecules in undifferentiated and committed HSCs residing in hEPCB and hTCB. In particular, although CD34(Pos)CD45(Dim)CD38(Pos) HSCs from both hEPCB and hTCB expressed relatively higher amounts of CD29, CD71, and CD135 compared with CD34(Pos)CD45(Dim)CD38(Neg) cells, a higher expression of CD31 was restricted to CD34(Pos)CD45(Dim)CD38(Pos) cells from hEPCB samples, and a higher expression of CD117 was demonstrated in CD34(Pos)CD45(Dim)CD38(Pos) cells from hTCB samples. Moreover, our data showed that CD34(Pos)CD45(Dim) cell population from hEPCB displayed higher percent of undifferentiated CD38(Neg)CD133(Pos) cells compared with hTCB samples. Finally, analyzing monocytes and lymphocytes within the two samples, we observed that T-cell percentages were higher in hTCB, whereas B-cell percentages were higher in hEPCB. We, therefore, studied the B-cell lineage maturation and found a higher percent of pro-B and pre-B cells in hEPCB compared with hTCB samples. Taken together, these results evidence the hematopoietic peculiarity of hEPCB, potentially useful for highlighting early steps of human hematolymphopoiesis as well as for developing novel strategies of stem cell-based therapy.

Right leg swelling as primary presentation of metastatic Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare malignant cutaneous neuroendocrine tumour with an aggressive behaviour and frequent regional lymph node and distant metastases. It mostly occurs in old patients and the commonest sites are the skin of the head, neck and the extremities. Typically, the primary tumour presents as a fast-growing, painless, reddish nodule with an iceberg-like effect, broadening in the depth. Although the pathogenesis of MCC remains largely unknown, ultraviolet radiation and immunosuppression are likely to play a significant pathogenetic role. The authors describe an unusual case of MCC clinically presenting as lymphedema on the right leg due to an inguinal lymphonodal metastasis. Although extensive investigations were performed the authors were unable to discover the cutaneous primary tumor. The authors examine the etiopathogenesis and hypothesis of this rare tumour and describe the clinical differential diagnosis. They suggest that clinical features together with imaging studies and morphological and immuno-histochemical findings are important for the correct diagnosis.

Critical role of multidimensional flow cytometry in detecting occult leptomeningeal disease in newly diagnosed aggressive B-cell lymphomas.

Among histological aggressive non-Hodgkin lymphomas (NHL), the overall risk of central nervous system (CNS) relapse is approximately 5%, a figure which is too low to offer prophylaxis to all patients. The aim of this work is to demonstrate the utility of flow cytometry (FCM) in detecting occult leptomeningeal disease in this subtype of NHL. We studied cerebrospinal fluid (CSF) involvement in 42 newly diagnosed aggressive NHL patients at risk for CNS involvement. We used multicolour FCM to detect CSF infiltrating neoplastic cells. Among the 42 patients studied, 11 had CSF involvement as detected by FCM. Of these, only four were also positive for conventional morphology (p=0.046). These results designate that FCM as the first choice technique in NHL CSF clinical cell analysis.

Rapid detection of mycoplasma in continuous cell lines using a selective biochemical test.

Mycoplasma contamination is a deleterious event for a cell culture laboratory due to the ability of this microorganism to contaminate cell culture leading up to the production of false data or, in the worst cases, to the loss of cell culture itself. Fortunately, mycoplasma can be eradicated by the use of antibiotics, but early detection of contamination is peremptory. Here, we propose the use of a sensitive and specific biochemical test named MycoAlert. In particular, as regards cell cultures not yet treated with antibiotics, sensitivity, specificity, positive and negative predictive values of MycoAlert assay gave excellent scores of 100%, 97%, 89% and 100%, respectively.

Sperm output in patients with primary infertility and hepatitis B or C virus; negative influence of HBV infection during concomitant varicocele.

AIM: The aim of this study was to evaluate the sperm abnormalities in young infertile patients with hepatitis B (HBV) or C (HCV) virus infection and to evaluate the additional negative influence of varicocele on sperm parameters in these patients. METHODS: Part I. Forty-two infertile patients in Child-Pugh classification A with HBV (n=23) or HCV (n=19) infection, underwent sperm analysis and quantitative detection of HBV-DNA or HCV-RNA in blood serum. Sperm parameters were compared to those of a group of 30 patients with primary infertility due to causes different from liver diseases and/or varicocele). Part II. Twenty-one infertile patients with varicocele associated to HBV (n=11) or HCV (n=10) infection were also enrolled and underwent semen analysis: a group of 39 patients without liver disease, but with varicocele alone served as matched-control group. RESULTS: Part I. HBV patients (with a median HBV-DNA load of 6x10(5) copies/mL, range 1x10(5)-10x10(6)) showed median sperm parameters (sperm density, total number, forward motility and morphology, viability) significantly worse than those found in patients with HCV (with a median HCV-RNA load of 2.3x10(6) copies/mL, range (2x10(5)-12x10(6)). Sperm parameters showed no significant correlation with the duration of infertility neither with the duration of viral infection. Sperm morphology only, exhibited a trend (P=0.06) of negative correlationship (r=-0.59) with the viral HBV-DNA load, whereas the other sperm parameters studied showed no correlation with the viral load. Part II. The group of infertile patients with HBV and varicocele showed median values of all sperm parameter evaluated significantly worse than those found in infertile patients with varicocele alone, or with HCV infection plus varicocele. CONCLUSIONS: Patients with HBV infection show worse sperm parameters compared with HCV patients. The additional presence of varicocele further impairs sperm output in HBV patients.

Role of charges and solvent on the conformational properties of poly(galacturonic acid) chains: a molecular dynamics study.

Pectin shares with many other polysaccharides an intrinsic chemical and physical complexity. The widespread industrial applications have made it one of the most studied polysaccharides. This work presents a theoretical model of poly(galacturonic acid), the major constituent of pectin, suitable to study its structural and dynamical properties. In particular, the effects of solvent and charge status are studied. The dynamics is shown to be severely affected by the presence of charged groups on each residue, making the charged chain much more rigid than the uncharged one. A key structural property for a semirigid polymer, the asymptotic persistence length, is calculated for relatively short charged and uncharged chains in molecular water solvent using a new method. The influence of charge on structural properties of poly(galacturonic acid) is shown to be strong and solvent-dependent. In fact, a large difference is found between continuum solvent adiabatic map calculations and molecular dynamics with explicit solvent, with the latter showing a much larger persistence length.

Randomized clinical trial to compare the effects of methadone and buprenorphine on the immune system in drug abusers.

RATIONALE: Buprenorphine may be a useful alternative option to methadone in addicts. Opioids can produce severe changes in the immune system. OBJECTIVES: The objectives of this study are to compare the effect of sublingual buprenorphine and methadone on the immune system and to compare the two substances on the drying-out program compliance. METHODS: We studied 62 randomized outpatients for a period of 12 months. Subjects (55 males and 7 females; mean age 25+/-4 years; average history of heroin abuse being 2 years) on maintenance treatment were assigned in two groups (A and B). Methadone chloride (medium dose 100 mg/day) was administered to group A, whereas group B received sublingual buprenorphine (32.40+/-2.8 mg/day). Urine toxicological screening, plasma levels of TNF-alpha interleukin-1, interleukin-beta, lymphocyte CD14 and a self-rating depression questionnaire were measured. RESULTS: Urine screening was negative for opiates in 17.6% of group A and in 10.7% of group B (p<0.001; r = 0.62). Depression score was 62+/-2 in group A and 55+/-3 in group B (p < 0.01). Cytokine and CD14 revealed higher concentrations both in groups A and B without significant differences (p > 0.05) between the two groups. CONCLUSIONS: The effects of buprenorphine and methadone tested on the immune system were overlapping in our patients. The elevated cytokine levels observed may suggest that the two drugs stimulate immunologic hyperactivation of an immune system that was formerly inhibited by heroin. Furthermore, our data suggest that buprenorphine can be a valid alternative to methadone in maintenance treatment of chronic heroin abuse and referred a marked decline in depression.

Hyperhomocysteinemia in preeclampsia is associated to higher risk pressure profiles.

Homocysteine levels have been determined with Chromatography on HPLC column, between the 20th and the 24th week of pregnancy, in women with analogous characteristics (a) normotensive, (b) with pregnancy-induced hypertension (PIH), low (LR), medium (MR), high risk (HR). The group they belonged to was confirmed after natural or caesarean delivery. All the patients were submitted to 24 hour blood pressure monitoring for the evaluation of further pressure risk parameters: mean arterial pressure (MAP), non dippers, percentages of pressure peaks. Homocysteine levels in normotensive pregnant women (5.8 +/- 1.7 microM) were low. Significant high levels of homocysteine were present proportionally to the risk degree of PIH. Higher levels of homocysteine statistically significant were present in non dippers of all groups (MR p < 0.05; HR p < 0.01). A direct correlation between plasmatic homocisteine levels and pressure profiles was found out in non dippers (r = 0.56, r = 0.55, r = 0.50 respectively) and in dippers (r = 0.7, r = 0.75, r = 0.60 respectively), and also between levels of homocysteine, MAP value, and pathological percentages of systolic and diastolic nocturnal peaks. In pregnant women presenting preeclampsia afterwards, high levels of homocysteine were not different from mean values present in high risk PIH pregnant women (13.3 +/- 1.9 vs. 16.4 +/- 1.7 microM). High levels of homocysteine early determined in the second trimester of PIH pregnancies seem to be associated to a pregnancy higher risk, coexisting with dangerous pressure profiles. High levels confirm a pregnant woman to belong to a higher or lower risk degree of vascular damage, but in the same group context high levels of homocisteine do not allow to identify those pregnant women who will develop eclampsia.

Improved growth with growth hormone therapy in a child with glycogen storage disease Ib.

UNLABELLED: In type Ib glycogen storage disease (GSD) growth is typically affected and short stature is a common feature. Reported use and effect of growth hormone (GH) therapy in children with GSD is limited. We report on the use of substitutive GH treatment in a poorly growing adolescent female with GSD type Ib. The patient's growth velocity increased from a baseline level of 2.5 cm/y to an average growth velocity during GH therapy of 8.7 cm/y. During GH therapy this patient did not demonstrate metabolic decompensation but increased levels of cholesterol and triglycerides were seen (A-1). CONCLUSION: Patients with GSD may experience an improvement in growth response with GH treatment. Prior to GH therapy, treatment of hyperlipidemia associated with GSD should allow the therapy to be safely tolerated.