Potential Role of 3-Dimensional Printed Vascular Models in Maintenance Hemodialysis Care

Infiltration of a surgically placed hemodialysis vascular access is recognized as a major contributor to the high health care costs associated with dialysis-dependent patients. Three-dimensional (3D) modeling is a critical tool for proceduralists in preparation for surgical interventions. No such modeling is currently available for dialysis specialists to avoid the common complication of vascular access infiltration. Ferumoxytol-enhanced magnetic resonance angiography was used to generate 3D image data that could render a 3D resin-based model of a vascular access without exposing the patient to iodinated or gadolinium-based radiologic contrast. The technique required an abbreviated magnetic resonance angiography procedure interfaced with a 3D printer workstation. An interventional radiology suite was not required. In the described case, the brachial artery was clearly delineated from a cephalic vein to basilic vein bypass with a 3D spatial resolution of 1 mm. In conclusion, we demonstrate that this new technology pathway can provide preprocedural guidance that has the potential to significantly reduce the morbidity and cost associated with vascular access infiltration.

Macrophage Migration Inhibitory Factor and microRNA-451a in Response to Mindfulness-based Therapy or Treatment as Usual in Patients with Depression, Anxiety, or Stress and Adjustment Disorders

BACKGROUND

Macrophage migration inhibitory factor is a proinflammatory cytokine that has been associated with various psychiatric disorders. MicroRNA-451a can directly target macrophage migration inhibitory factor and downregulate its expression in cells. However, the role of macrophage migration inhibitory factor and microRNA-451a in psychiatric patients treated with psychotherapeutic interventions is unknown. In this study, our aim was to investigate levels of macrophage migration inhibitory factor and its regulating microRNA-451a in patients with depression, anxiety, or stress and adjustment disorders who underwent mindfulness-based therapy or treatment as usual.

METHODS

A total of 168 patients with psychiatric disorders were included from a randomized controlled trial that compared mindfulness-based therapy with treatment as usual. Plasma levels of macrophage migration inhibitory factor and microRNA-451a were measured at baseline and after the 8-week follow-up using Luminex assay and qPCR.

RESULTS

Macrophage migration inhibitory factor levels decreased significantly in patients posttreatment, whereas microRNA-451a levels showed a nonsignificant change. Macrophage migration inhibitory factor levels were inversely associated with microRNA-451a expression levels at baseline (β=-0.04, P=.008). The change in macrophage migration inhibitory factor levels (follow-up levels minus baseline levels) was associated with the change in microRNA-451a (follow-up levels minus baseline levels) (β=-0.06, P < .0001). The change in either macrophage migration inhibitory factor or microRNA-451a was not associated with improvement in psychiatric symptoms.

CONCLUSION

We demonstrate that the levels of macrophage migration inhibitory factor decreased after psychotherapeutic interventions in patients with psychiatric disorders. However, this reduction was not associated with an improvement in psychiatric symptoms in response to the treatment. We also found an association between macrophage migration inhibitory factor and its regulating microRNA. However, this association needs to be further examined in future studies.

Role of family history of venous thromboembolism and thrombophilia as predictors of recurrence: a prospective follow-up study

BACKGROUND

Several studies have shown that the family history of venous thromboembolism (FHVTE) is a predictor of first venous thromboembolism (VTE). However its role in recurrent VTE is still controversial.

OBJECTIVES

To investigate whether the presence of FHVTE is a risk factor for VTE recurrence in patients from a well-characterized Malmö thrombophilia study.

METHODS

VTE patients from the Malmö Thrombophilia Study were followed from discontinuation of warfarin treatment until diagnosis of VTE recurrence or to the end of the study (maximum follow-up 9.8 years).

RESULTS

There were 127 events of VTE recurrence (12.2%) registered during the follow-up. Multivariate Cox regression analysis in patients with unprovoked first VTE showed that FHVTE was associated with higher risk of VTE recurrence (hazard ratio [HR] 1.9, 95% confidence interval [CI] 1.2-2.9) compared with patients with no FHVTE. Stratification of data according to thrombophilia status of patients showed that compared with the reference group (no FHVTE or thrombophilia), thrombophilia together with FHVTE was associated with a higher risk of VTE recurrence (HR 3.2, 95% CI 1.8-5.9) than thrombophilia alone (HR 1.8, 95% CI 1.02-3.2) independent of DVT location and duration of warfarin treatment. FHVTE was mainly an important risk factor of VTE recurrence in women (HR 3.1, 95% CI 1.6-5.8) but not in men (HR 1.1, 95% CI 0.6-2.2).

CONCLUSION

Our results show that FHVTE is a risk factor for VTE recurrence in patients who had unprovoked first VTE. Furthermore, presence of FHVTE may be an additional risk factor of VTE recurrence in thrombophilia-positive patients.

The association between apolipoprotein M and insulin resistance varies with country of birth

BACKGROUND AND AIMS

Risk of type 2 diabetes mellitus (T2DM) differs according to ethnicity. Levels of apolipoprotein M (ApoM) have been shown to be decreased in T2DM. However, its role in different ethnicities is not known. We examined the differences in plasma ApoM levels in Swedish residents born in Iraq (Iraqis) and Sweden (Swedes) in relation to T2DM and insulin resistance (IR).

METHODS AND RESULTS

Iraqis and Swedes, aged 45-65 years residing in Rosengård area of Malmö were randomly selected from census records and underwent an oral glucose tolerance test. Plasma levels of ApoM were quantified in 162 participants (Iraqis, n = 91; Swedes, n = 71) by a sandwich ELISA method. Age-, sex-, and body mass index (BMI) adjusted plasma ApoM levels differed by country of birth, with Swedes having 18% higher levels compared to Iraqis (p = 0.001). ApoM levels (mean ± SD) were significantly decreased in Swedes with T2DM (0.73 ± 0.18) compared to those with normal glucose tolerance (NGT) (0.89 ± 0.24; p = 0.03). By contrast, no significant difference in ApoM levels was found between Iraqis with T2DM (0.70 ± 0.17) and those with NGT (0.73 ± 0.13; p = 0.41). In multivariate linear regression analysis with an interaction term between IR and country of birth, low ApoM levels remained significantly associated with IR in Swedes (p = 0.008), independently of age, sex, BMI, family history of diabetes, HDL, LDL, and triglycerides, but not in Iraqis (p = 0.35).

CONCLUSION

Our results show that ApoM levels differ according to country of birth and are associated with IR and T2DM only in Swedes.

Helicobacter pylori downregulates expression of human β-defensin 1 in the gastric mucosa in a type IV secretion-dependent fashion

Helicobacter pylori establishes a chronic lifelong infection in the human gastric mucosa, which may lead to peptic ulcer disease or gastric adenocarcinoma. The human beta-defensins (hβDs) are antimicrobial peptides, hβD1 being constitutively expressed in the human stomach. We hypothesized that H. pylori may persist, in part, by downregulating gastric hβD1 expression. We measured hβD1 and hβD2 expression in vivo in relation to the presence, density and severity of H. pylori infection, investigated differential effects of H. pylori virulence factors, and studied underlying signalling mechanisms in vitro. Significantly lower hβD1 and higher hβD2 mRNA and protein concentrations were present in gastric biopsies from infected patients. Those patients with higher-level bacterial colonization and inflammation had significantly lower hβD1 expression, but there were no differences in hβD2. H. pylori infection of human gastric epithelial cell lines also downregulated hβD1. Using wild-type strains and isogenic mutants, we showed that a functionalcag pathogenicity island-encoded type IV secretion system induced this downregulation. Treatment with chemical inhibitors or siRNA revealed that H. pylori usurped NF-κB signalling to modulate hβD1 expression. These data indicate that H. pylori downregulates hβD1 expression via NF-κB signalling, and suggest that this may promote bacterial survival and persistence in the gastric niche.

Prevalence and distribution of Arcobacter spp. in raw milk and retail raw beef

A total of 106 beef samples which consisted of local (n = 59) and imported (n = 47) beef and 180 milk samples from cows (n = 86) and goats (n = 94) were collected from Selangor, Malaysia. Overall, 30.2% (32 of 106) of beef samples were found positive for Arcobacter species. Imported beef was significantly more contaminated (46.80%) than local beef (16.9%). Arcobacter butzleri was the species isolated most frequently from imported (81.8%) and local (60%) beef, followed by Arcobacter cryaerophilus in local (33.3%) and imported (18.2%) beef samples. Only one local beef sample (10%) yielded Arcobacter skirrowii. Arcobacter species were detected from cow's milk (5.8%), with A. butzleri as the dominant species (60%), followed by A. cryaerophilus (40%), whereas none of the goat's milk samples were found positive for Arcobacter. This is the first report of the detection of Arcobacter in milk and beef in Malaysia.

PET imaging of patients with non-small cell lung cancer employing an EGF receptor targeting drug as tracer

Background:

We have previously developed ¹¹C-erlotinib as a new positron emission tomography (PET) tracer and shown that it accumulates in epidermal growth factor receptor (EGFR)-positive lung cancer xenografts in mice. Here, we present a study in patients with non-small cell lung cancer (NSCLC) investigating the feasibility of ¹¹C-erlotinib PET as a potential method for the identification of lung tumours accumulating erlotinib.

Methods:

Thirteen patients with NSCLC destined for erlotinib treatment were examined by contrast-enhanced computed tomography (CT), ¹¹C-erlotinib PET/low-dose CT and ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) PET/low-dose CT before start of the erlotinib treatment. After 12 weeks treatment, they were examined by ¹⁸F-FDG PET/contrast-enhanced CT for the assessment of clinical response.

Results:

Of the 13 patients included, 4 accumulated ¹¹C-erlotinib in one or more of their lung tumours or lymph-node metastases. Moreover, ¹¹C-erlotinib PET/CT identified lesions that were not visible on ¹⁸F-FDG PET/CT. Of the four patients with accumulation of ¹¹C-erlotinib, one died before follow-up, whereas the other three showed a positive response to erlotinib treatment. Three of the nine patients with no accumulation died before follow-up, four showed progressive disease while two had stable disease after 12 weeks of treatment.

Conclusion:

Our data show a potential for ¹¹C-erlotinib PET/CT for visualizing NSCLC lung tumours, including lymph nodes not identified by ¹⁸F-FDG PET/CT. Large clinical studies are now needed to explore to which extent pre-treatment ¹¹C-erlotinib PET/CT can predict erlotinib treatment response.

The epidermal growth factor family has a dual role in deciding the fate of cancer cells

Expression of the epidermal growth factor (EGF) receptors HER1 and HER2 has been implicated in tumour growth and poor survival, whereas expression of HER3 and HER4 has been associated with improved survival of bladder cancer patients. The balance between the expression of the EGF family members may therefore have a role to play in determining the final outcome in cancer cells. To check this, we examined the effect of HER1 activation and inhibition on the expression of the EGF receptors HER3 and HER4 and ligands - the heregulins (HRGs). RT4 bladder cancer cells were treated with 1nM HB-EGF (known to induce cell proliferation by activating HER1 receptor) and the mRNA content of the two receptors (HER3 and HER4) and their activating ligands (HRG1-HRG4) was quantified by real time PCR at indicated time-points. Expressions of HRG1alpha and HRG1beta increased 8-fold and 9-fold, respectively, whereas the expressions of HRG2alpha (4-fold), HRG2beta (2.5-fold) and HRG4 (3.5-fold) decreased. In contrast, inhibition of tyrosine kinase activity of HER1 with 5 microM Iressa (a specific inhibitor of HER1) resulted in an increase in mRNA expression of HRG2alpha (2.5-fold) and HRG4 (1.5-fold). In addition, expression of the receptors HER3 (1.5-fold) and HER4 (2-fold) was also increased. In conclusion, we demonstrate that activation of the HER1 receptor suppressed the expression of a specific set of HRGs. A decrease in expression of HRG2 and HRG4 during HB-EGF treatment supports their role in growth inhibition, whereas an increase in HRG1 expression points to a role as a growth stimulatory member of the EGF family.

The relation between survival and expression of HER1 and HER2 depends on the expression of HER3 and HER4: a study in bladder cancer patients

Increased expression of the epidermal growth factor (EGF) receptors, HER1 and HER2 are related to poor prognosis in most cancers studied. Recently, a high expression of the two remaining receptors of the EGF system, HER3 and HER4 has been related to a favourable prognosis. However, prognostic significance of HER1 and HER2 receptors in bladder cancer is controversial and the effect of the expression of different combinations of these receptors on patient survival is not well understood. Therefore, we examined the mRNA expression of all four EGF receptors with real-time polymerase chain reaction in biopsies from 88 patients with bladder cancer, where the survival was followed for a median of 38.5 months (range 1-117 months). Expression of HER1 and HER2 alone showed no correlation with survival. However, a high expression of HER1 together with high expression of HER3 and HER4 correlated to a better prognosis compared to the high expression of HER1 together with low expression of HER3 and HER4 (P=0.0006). Also, a significantly longer survival was observed in patients expressing high HER2 when coexpressed with high HER3 and HER4, as compared to the survival in patients with tumours expressing high HER2 but low HER3 and HER4 (P=0.0005). Our results suggest that the final outcome of patients with high HER1- and HER2-expressing tumours depends on the expression of HER3 and HER4.

Expression of HER3, HER4 and their ligand heregulin-4 is associated with better survival in bladder cancer patients

The epidermal growth factor system has been associated to prognosis in patients with bladder cancer based mainly on the expression of the epidermal growth factor (EGF) receptor 1 (EGFR) and HER2 and their activating ligands. Since limited information exists concerning the expression of other parts of the EGF system, we examined the expression of the receptors HER3 and HER4 and their activating ligands, the heregulins (HRGs), in bladder cancer patients. Biopsies from bladder cancer tumours were obtained from 88 patients followed for a median of 23 months (range, 1-97 months). The mRNA content of four ligands and their isoforms (HRG1alpha, HRG1beta, HRG2alpha, HRG2beta, HRG3 and HRG4) and two receptors (HER3 and HER4) was quantified by real-time PCR. A significantly lower mRNA expression level of HER3 (P=0.0003), HRG2alpha (P=0.0159), HRG2beta (P=0.0007) and HRG4 (P<0.0001) was observed in muscle-invasive (T2-T4) tumours as compared to superficial (Ta) tumours. The expression of HER3 mRNA correlated strongly to overall survival (P=0.0042); increased expression of HER4 (P=0.0261) and HRG4 (P=0.0245) was also associated with better prognosis. Interestingly, patients with coexpression of HER3 (P=0.0034) or HER4 (P=0.0080) together with their stimulating ligand HRG4 showed even better survival than for HER3 or HER4 alone. Our results together with previous data suggest a dual face for the EGF system. While it is well established that an increased signalling through HER1 and HER2 is related to a poor prognosis, our data suggest that signalling through HER3 and HER4 is related to a favourable outcome in bladder cancer patients.

Prevalence of solar damage and actinic keratosis in a Merseyside population

This study examines the prevalence of sun-related damage to the skin in a caucasian population in north-west England. The importance of constitutional factors (complexion, skin type and age) as well as environmental and occupational exposures for the development of actinic keratosis (AK) and skin cancers was assessed in people over 40 years of age attending outpatient clinics (non-dermatology) at four centres in north-west England (Mersey region). Nine hundred and sixty-eight volunteers (531 men and 437 women) were recruited. The overall prevalence of AK was 15.4% in men and 5.9% in women. The prevalence was strongly related to age in both sexes, being 34.1% and 18.2%, respectively, in men and women aged 70 years and above, and was most strongly related to two objective signs of sun exposure, namely degree of solar elastosis and presence of solar lentigines. The prevalence of AK was higher in subjects with red hair and freckles, particularly women. There was no evidence of an increased prevalence of AK in relation to any occupation. There was a high prevalence of seborrhoeic keratosis and viral warts in both sexes, which was age-related in the case of seborrhoeic keratosis. Ten cases of basal cell carcinoma, eight cases of Bowen's disease and one case of malignant melanoma were identified. This study shows that the sun exposure received in 'normal' life in England is sufficient to cause potentially malignant skin damage in a significant proportion of the population.

Capillary gas chromatographic determination of putrescine and cadaverine in serum of cancer patients using trifluoroacetylacetone as derivatizing reagent

Trifluoroacetylacetone (FAA) derivatives of 1,4-diaminobutane (putrescine) (Pu) and 1,5-diaminopentane (cadaverine) (CA) were prepared and characterized by elemental microanalysis, IR, and mass spectrometry. Diamine derivatives were eluted from capillary gas chromatographic (CGC) column BP1 (12 m x 0.22 mm I.D.) or BP5 (50 m x 0.22 mm) with layer thickness 0.25 microm, using nitrogen as a carrier gas and flame ionization detection (FID). A solvent extraction procedure was developed for the extraction of Pu and CA from aqueous solution with a linear calibration range 0-20 microg/0.2 ml of extract with a detection limit of 0.5-0.6 ng/injection. The method was applied for the determination of Pu and CA in the serum of five cancer patients before and after radiotherapy. The serum of two healthy persons was also analyzed for Pu and CA contents. Pu and CA concentrations were found within the range 1.16-3.96 microg/ml and 0.88-1.46 microg/ml in cancer patients as compared to 0.11-0.16 microg/ml and 0.06-0.075 microg/ml respectively in healthy persons with a coefficient of variation (CV) within 0.62-5.47%. Pu and CA concentrations decreased on radiotherapy in cancer patients, but were much higher than in healthy persons.

'Angry back syndrome': a non-reproducible phenomenon

The term 'angry back syndrome' (ABS) was coined by Mitchell in 1975. It was stated that a strong positive patch test reaction could create an 'angry back' which becomes hyper-reactive to other patch test challenges. The present study investigated whether the ABS is a generalized state of hyper-reactivity of skin, whether it is a localized hyper-reactivity of skin, i.e. only in the close proximity to a strong patch test reaction, whether it is an individual specific phenomenon and if ABS is a reproducible phenomenon. The studies failed to demonstrate any generalized or localized change in the reactivity of the skin. This left the possibility that ABS might be a rare, and individual-specific phenomenon. However, even in the subjects who had previously been diagnosed as having ABS we failed to reproduce the angry back.

Stapled anastomoses in colorectal surgery: a prospective study

OBJECTIVE

To evaluate the safety and efficacy of stapled anastomosis in left sided colorectal reconstructions.

DESIGN

Prospective study.

SETTING

District hospital, UK.

SUBJECTS

218 Consecutive patients who underwent elective colorectal reconstructions with stapled anastomoses between July 1980 and July 1994.

INTERVENTIONS

154 Anterior resections of the rectum using single or double stapled anastomoses, 37 rejoining after Hartmann's operations, and 28 restorative proctocolectomies with formation of J pouch ileoanal anastomoses.

MAIN OUTCOME MEASURES

Morbidity and mortality.

RESULTS

There were 5/154 clinical anastomotic leaks after anterior resection of the rectum and 1/28 after stapled J pouch ileoanal anastomoses. There were no leaks after rejoining of Hartmann's. The overall clinical leak rate was therefore 3%. 11/154 tumours recurred locally after anterior resection of the rectum (7%) during a mean follow up of 18 months, and 8 (73%) developed within 2 years of operation. All but one recurrence developed after single stapled anastomosis. Dukes' staging remains the most reliable prognostic indicator of the local recurrence of the tumour. There were five postoperative deaths after anterior resection but none after Hartmann's procedure or J pouch ileoanal anastomosis, giving an overall postoperative mortality of 2.3%.

CONCLUSION

The use of stapling instruments in left sided colorectal anastomosis is safe and technically easy, with a low clinical anastomotic leak rate and an acceptable rate of local recurrence after anterior resection of the rectum.

Studies on the reproducibility of allergic contact dermatitis

Diagnosis of allergic contact dermatitis depends upon the use of epicutaneous patch tests with suspected antigens. It has been claimed that the method is unreliable because of variability. Therefore, we have tested this by comparing responses to various forms of replicate, standardized challenge in nickel-sensitive subjects. Nickel-containing coins applied at 2-4 different sites on the back elicited similar responses in up to 95% of tests. Serial dilutions of nickel sulphate (NiSO4) applied, in duplicate, gave highly reproducible responses on the back. However, the forearm skin was clearly less responsive. Examination of the effect of the quantity of nickel-containing vehicle showed that, above a certain minimal level, this had no effect on the reproducibility of the responses. In conclusion, the immune system can give highly reproducible responses when presented with standard eliciting stimuli.

The inhibitory effects of topical chelating agents and antioxidants on nickel-induced hypersensitivity reactions

BACKGROUND

Nickel sensitivity is a common problem, often causing significant morbidity from chronic eczematous dermatitis. The main treatment, topical steroids, usually is unable to suppress the dermatitis completely.

OBJECTIVE

Our purpose was to study the effects of "barrier" ointments containing either chelating agents (clioquinol or ethylenediaminetetraacetic acid [EDTA]) or antioxidants (ascorbic acid or alpha-tocopherol) and 1% hydrocortisone on nickel-induced hypersensitivity reactions.

METHODS

Nickel-sensitive subjects were challenged with nickel-containing coins coated with the desired barrier ointment and their inhibitory effects observed. Patients with bilateral hand or earring dermatitis explored the efficacy of these agents in clinical use.

RESULTS

Clioquinol (3%) completely abolished the allergic reaction in all 29 subjects tested. EDTA (15%), ascorbic acid (20%), and alpha-tocopherol (10%) were less effective, and 1% hydrocortisone had no significant effect. In clinical use sites treated with a commercially available preparation containing 3% clioquinol and 1% hydrocortisone showed marked clinical improvement in all 10 subjects.

CONCLUSION

Clioquinol is a potent inhibitor of nickel-induced hypersensitivity reactions and is feasible to use as a barrier ointment to block the allergenic effects of nickel in sensitive patients.

Early time course of recruitment of immune surveillance in human skin after chemical provocation

As part of the defence function of skin it seems probable that mechanisms exist for the rapid recruitment of immune surveillance to 'inspect' any foreign substance that penetrates the skin. In the present study, evidence of such mechanisms was sought by following the time course of early changes in distribution of immune cells, expression of cell adhesion molecules and cytokines after epicutaneous challenge with provoking chemicals to which subjects were known to be either specifically 'sensitive' or 'non-sensitive'; anthralin, an irritant chemical, was used as control. Fifty-seven individuals were studied and there were at least five biopsy samples at each time point. Regardless of whether individuals were sensitive or not, or of the type of chemical, dermal microvascular endothelial cells showed increased expression of the adhesion molecules ELAM-1 and VCAM-1 within 2 h, and ICAM-1 within 8 h. The intensity of immunohistochemical staining increased progressively up to 24 h. More vessels stained for ICAM-1 than for VCAM-1 or ELAM-1, implying that not every vessel expressed all three cell adhesion molecules. Another early change, observed 2 h after irritant challenge, was a significant increase in numbers of CD1a+ dendritic cells in the superficial dermis from a median of 3/high power field (hpf) to 9.5/hpf (P < 0.03). This was not observed with 'weak' provoking substances, such as nickel, but did occur with the potent provoking agent dinitrochlorobenzene (DNCB). Thus, as little as 2 h after contact with provoking chemicals, the skin activates cellular mechanisms to increase T cell infiltration for the presumed purpose of immune surveillance. These mechanisms are not dependent upon specific immune sensitivity and reflect a capacity of skin cells to respond to chemical provocation.