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61.
Bone marrow angiogenesis has recently been implicated in the pathophysiology and course of various haematological malignancies. Little is known, however, about the significance of this phenomenon in hairy cell leukaemia (HCL). We evaluated various morphometric characteristics of microvessels, highlighted by means of anti-CD34 immunohistochemistry, in the bone marrow of 44 patients with typical HCL, before and after treatment with interferon-alpha (IFN-alpha). Overall, bone marrow from 103 HCL patients and 20 controls was examined. Microvessel density (MVD) and several size- and shape-related parameters were quantified in the region of most intense vascularization using image analysis. MVD, size-related parameters and the percentage of branching microvessels were higher in HCL than in controls. Likewise, perimeter counts were higher in partial/non-responders than in complete responders. Achievement of complete response was accompanied by smaller calibre microvessels. IFN-alpha induced a decrease in MVD and branching values in cases with diffuse marrow involvement. In univariate analysis, progression-free survival was adversely affected by MVD, branching and major axis length. Multivariate analysis indicated that MVD/branching independently affected progression-free survival and the likelihood of complete response. Our data suggest that the generation of bone marrow microvessels indicated an increased risk of progression and IFN-alpha treatment failure in HCL. Furthermore, the prognostic significance of angiogenesis requires the concomitant assessment of MVD and the complexity of the microvascular network.  相似文献   
62.
Somatostatin (SST) acts as an inhibitory peptide of various secretory and proliferative processes. Apart from neuroendocrine tumors, where SST analogues have an established role, they have been tested in other tumors such as hepatocellular carcinoma (HCC) in the view of the fact that chemotherapy is not working. Several positive reports have been published. Approximately 40% of patients respond with improved survival and an impressive quality of life. A usual misunderstanding in trial designs is that, although SST is not a rescue drug, selection of patients is inappropriate, with mostly moribund patients being recruited. SST analogues do not seem to work in 60% of HCCs and this has been linked to the presence of SST receptors (SSTR) in the tumor, while several resistance mechanisms might be involved. Future management should engage more specific SST analogues targeted to a tumor with a known SSTR map. The use of somatostatin analogues as an adjunct therapy in combination with other treatment modalities should also be investigated.  相似文献   
63.

Aims

To study the impact of diabetic neuropathy, both peripheral sensorimotor (DPN) and cardiac autonomic neuropathy (CAN), on transcutaneous oxygen tension (TcPO2) in patients with type 2 diabetes mellitus (T2DM).

Methods

A total of 163 participants were recruited; 100 with T2DM and 63 healthy individuals. Peripheral arterial disease (PAD) was defined as ankle-brachial index (ABI) values ≤0.90. Diagnosis of DPN was based on neuropathy symptom score and neuropathy disability score (NDS), while diagnosis of CAN on the battery of the cardiovascular autonomic function tests. TcPO2 was measured using a TCM30 system.

Results

Patients with T2DM had lower TcPO2 levels when compared with healthy individuals. Among the diabetic cohort, those who had either PAD, DPN or CAN had significantly lower TcPO2 values than participants without these complications. Multivariate linear regression analysis, after controlling for diabetes duration, diastolic blood pressure, HbA1c, albumin to creatinine ratio and CAN score, demonstrated that TcPO2 levels were significantly and independently associated with current smoking (p?=?0.013), ABI (p?=?0.003), and NDS (p?=?0.013).

Conclusion

Presence of DPN is independently associated with impaired cutaneous perfusion. Low TcPO2 in subjects with DPN may contribute to delay in healing of diabetic foot ulcers, irrespectively of PAD.  相似文献   
64.
BACKGROUND: To explore the effect of short-term cholesterol-lowering treatment with atorvastatin on erythrocyte sodium-lithium countertransport (Na(+)/Li(+) CT) activity. METHODS: Group A consisted of 30 patients (14 men) with mild essential hypertension (systolic blood pressure (SBP), 140-159 mm Hg and/or diastolic BP, 90-99 mm Hg) and primary hypercholesterolemia low-density lipoprotein (LDL) cholesterol >4.1 mmol/l and triglycerides (TG) <2.8 mmol/l), group B of 30 normotensive patients (16 men) with primary hypercholesterolemia, while 37 (18 men) healthy volunteers comprised the control group. After a 6-week dietary lead-in, all eligible patients were prescribed 20 mg/day of atorvastatin. Anthropometric data, blood-pressure (BP) measurements and determinations of lipid, non-lipid metabolic parameters (including homeostasis model assessment index, (HOMA-IR)) and erythrocyte Na(+)/Li(+) CT activity were collected at baseline and after 12 weeks of treatment. RESULTS: At baseline Na(+)/Li(+) CT activity was significantly higher in group A and B compared with the control group and correlated directly with obesity indices, systolic and diastolic BP, total cholesterol, LDL-cholesterol, TG, apolipoprotein B (apoB), HOMA-IR, uric acid and inversely with high-density lipoprotein (HDL)-cholesterol and apoA1. Systolic and diastolic BP levels, HOMA-IR and Na(+)/Li(+) CT activity were significantly decreased after atorvastatin treatment in both patient groups. The reduction in Na(+)/Li(+) CT activity correlated with baseline Na(+)/Li(+) CT activity and the changes in HOMA-IR values. CONCLUSIONS: Short-term treatment with atorvastatin for patients with hypercholesterolemia, and with or without essential hypertension, is associated with a significant reduction in the erythrocyte Na(+)/Li(+) CT activity, BP levels and insulin resistance independent of concomitant changes in lipid parameters.  相似文献   
65.
A novel strategy employing the rhabdovirus untranslated conserved intergenic regions was developed and applied successfully for the determination of the complete nucleotide sequence of Eggplant mottled dwarf virus (EMDV). The EMDV genome contains seven open reading frames with the same organization as Potato yellow dwarf virus (PYDV), the type species of the genus Nucleorhabdovirus. These two species encode five core genes [nucleocapsid (N), phosphoprotein (P), matrix (M), glycoprotein (G), and the polymerase (L)] like other viruses of the genus and an additional one (X), located between N and P, giving rise to a protein with currently unknown function. Furthermore, both EMDV and PYDV contain a gene (Y), inserted between P and M, which probably encodes the virus movement protein, in concordance with the rest of the plant-infecting rhabdoviruses. Phylogenetic analysis of the polymerase gene confirmed the classification of EMDV within the genus Nucleorhabdovirus and showed a close evolutionary relationship to PYDV. The novel sequencing strategy developed is a useful tool for the genome determination of yet uncharacterized rhabdoviruses.  相似文献   
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68.
ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics.  相似文献   
69.
ObjectiveViruses on environmental surfaces, in saliva and other body fluids represent risk of contamination for general population and healthcare professionals. The development of vaccines and medicines is costly and time consuming. Thus, the development of novel materials and technologies to decrease viral availability, viability, infectivity, and to improve therapeutic outcomes can positively impact the prevention and treatment of viral diseases.MethodsHerein, we discuss (a) interaction mechanisms between viruses and materials, (b) novel strategies to develop materials with antiviral properties and oral antiviral delivery systems, and (c) the potential of artificial intelligence to design and optimize preventive measures and therapeutic regimen.ResultsThe mechanisms of viral adsorption on surfaces are well characterized but no major breakthrough has become clinically available. Materials with fine-tuned physical and chemical properties have the potential to compromise viral availability and stability. Emerging strategies using oral antiviral delivery systems and artificial intelligence can decrease infectivity and improve antiviral therapies.SignificanceEmerging viral infections are concerning due to risk of mortality, as well as psychological and economic impacts. Materials science emerges for the development of novel materials and technologies to diminish viral availability, infectivity, and to enable enhanced preventive and therapeutic strategies, for the safety and well-being of humankind.  相似文献   
70.
Objectives

To compare the efficacy, acceptance and preference of conventional infiltration technique with a needleless jet anaesthetic device (Comfort-In).

Materials and methods

Non-fearful healthy adult volunteers, aged 19–40 years, were recruited in the Dental School of Aristotle University of Thessaloniki, Greece. Intact maxillary premolars were selected for local anaesthesia. Both techniques were applied sequentially with 35 min time gap on either buccal side on the same day by the same operator. The quadrant and the order of administration were randomly assigned using an online randomization generator. Immediately after administration, at 1, 3, 5, 10, 15, 20, 25 and 30 min, pulp vitality and soft tissue pain reaction tests were performed. Each participant was asked 6 questions in order to assess acceptance. At the end of the session, at 24 h and 7 days, all participants were asked to report any adverse events and their preference.

Results

In 63 volunteers who were successfully followed, 63 teeth received conventional local infiltration and 63 the Comfort-In. Both techniques presented with similar anaesthetic efficacy at 1, 3, 5, 10 and 15 min, whereas the conventional technique was more efficacious at 20 min (p < 0.005). Both presented similar acceptance apart from higher pain/discomfort during administration of Comfort-In (p = 0.002). Significantly higher preference was reported for the conventional technique immediately after the session, at 24 h and at 7 days (p < 0.0005); 19 (30.2%) reported the presence of ecchymosis or lacerations at the Comfort-In site as opposed to 5 (7.9%) with the conventional method (p < 0.0001).

Conclusion

Both techniques showed similar effectiveness. Conventional infiltration was preferred to needleless anaesthesia by non-fearful adult volunteers and was associated with less adverse events.

Clinical relevance

This study enhances the advantages of conventional local anaesthesia.

Trial registration

ISRCTN17400733

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