Predictors of Exacerbations in Chronic Obstructive Pulmonary Disease - Results from the Bergen COPD Cohort Study

Background

COPD exacerbations accelerate disease progression.

Aims

To examine if COPD characteristics and systemic inflammatory markers predict the risk for acute COPD exacerbation (AECOPD) frequency and duration.

Methods

403 COPD patients, GOLD stage II-IV, aged 44–76 years were included in the Bergen COPD Cohort Study in 2006/07, and followed for 3 years. Examined baseline predictors were sex, age, body composition, smoking, AECOPD the last year, GOLD stage, Charlson comorbidity score (CCS), hypoxemia (PaO2<8 kPa), cough, use of inhaled steroids, and the inflammatory markers leucocytes, C-reactive protein (CRP), neutrophil gelatinase associated lipocalin (NGAL), soluble tumor necrosis factor receptor 1 (sTNF-R1), and osteoprotegrin (OPG). Negative binomial models with random effects were fitted to estimate the annual incidence rate ratios (IRR). For analysis of AECOPD duration, a generalized estimation equation logistic regression model was fitted, also adjusting for season, time since inclusion and AECOPD severity.

Results

After multivariate adjustment, significant predictors of AECOPD were: female sex [IRR 1.45 (1.14–1.84)], age per 10 year increase [1.23 (1.03–1.47)], >1 AECOPD last year before baseline [1.65 (1.24–2.21)], GOLD III [1.36 (1.07–1.74)], GOLD IV [2.90 (1.98–4.25)], chronic cough [1.64 (1.30–2.06)] and use of inhaled steroids [1.57 (1.21–2.05)]. For AECOPD duration more than three weeks, significant predictors after adjustment were: hypoxemia [0.60 (0.39–0.92)], years since inclusion [1.19 (1.03–1.37)], AECOPD severity; moderate [OR 1.58 (1.14–2.18)] and severe [2.34 (1.58–3.49)], season; winter [1.51 (1.08–2.12)], spring [1.45 (1.02–2.05)] and sTNF-R1 per SD increase [1.16 (1.00–1.35)].

Conclusion

Several COPD characteristics were independent predictors of both AECOPD frequency and duration.     

Prognostic Significance of Tumor-Associated Macrophages in Solid Tumor: A Meta-Analysis of the Literature

Purpose

Tumor associated macrophages (TAMs) are considered with the capacity to have both negative and positive effects on tumor growth. The prognostic value of TAM for survival in patients with solid tumor remains controversial.

Experimental Design

We conducted a meta-analysis of 55 studies (n = 8,692 patients) that evaluated the correlation between TAM (detected by immunohistochemistry) and clinical staging, overall survival (OS) and disease free survival (DFS). The impact of M1 and M2 type TAM (n = 5) on survival was also examined.

Results

High density of TAM was significantly associated with late clinical staging in patients with breast cancer [risk ratio (RR)  = 1.20 (95% confidence interval (CI), 1.14–1.28)] and bladder cancer [RR = 3.30 (95%CI, 1.56–6.96)] and with early clinical staging in patients with ovarian cancer [RR = 0.52 (95%CI, 0.35–0.77)]. Negative effects of TAM on OS was shown in patients with gastric cancer [RR = 1.64 (95%CI, 1.24–2.16)], breast cancer [RR = 8.62 (95%CI, 3.10–23.95)], bladder cancer [RR = 5.00 (95%CI, 1.98–12.63)], ovarian cancer [RR = 2.55 (95%CI, 1.60–4.06)], oral cancer [RR = 2.03 (95%CI, 1.47–2.80)] and thyroid cancer [RR = 2.72 (95%CI, 1.26–5.86)],and positive effects was displayed in patients with colorectal cancer [RR = 0.64 (95%CI, 0.43–0.96)]. No significant effect was showed between TAM and DFS. There was also no significant effect of two phenotypes of TAM on survival.

Conclusions

Although some modest bias cannot be excluded, high density of TAM seems to be associated with worse OS in patients with gastric cancer, urogenital cancer and head and neck cancer, with better OS in patients with colorectal cancer.     

Excess Body Weight and Cancer Risk in Patients with Type 2 Diabetes Who Were Registered in Swedish National Diabetes Register – Register-Based Cohort Study in Sweden

Aim

To assess the association between excess body weight and cancer risk in patients with type 2 diabetes (T2D) who were registered in the Swedish National Diabetes Register (NDR).

Methods

This is a cohort study based on 25,268 patients with T2D and baseline BMI≥18.5 kg/m² from NDR 1997–1999. Subjects were grouped according to BMI into normal weight (18.5 to 24.9), overweight (25 to 29.9) or obesity (30 or more). All subjects were followed until the first occurrence of cancer, or death, or the end of follow-up (December 31, 2009). Adjusted hazard ratios (HRs) and 95% confidence interval (CI) for cancer risks were estimated by Cox regression.

Results

In men with T2D, overweight was associated with increased risks of all cancer [1.13 (1.02–1.27)], gastrointestinal cancer [1.34 (1.07–1.72)] and colorectal cancer [1.59 (1.18–2.13)]; obesity was related to higher risks of all cancer [1.17 (1.04–1.33)], gastrointestinal cancer [1.40 (1.08–1.82)] and colorectal cancer [1.62 (1.17–2.24)]. In women with T2D, obesity was associated with increased risk of all cancer [1.30 (1.12–1.51)], gastrointestinal cancer [1.40 (1.03–1.91)] and postmenopausal breast cancer [1.39 (1.00–1.91)].

Conclusions

Excess body weight was associated with increased risks of all cancer, gastrointestinal cancer and colorectal cancer in men with T2D. Obesity was related with elevated risks of all cancer, gestational cancer and postmenopausal breast cancer in women with T2D.     

Risk Factors Associated with Default among New Smear Positive TB Patients Treated Under DOTS in India

Background

Poor treatment adherence leading to risk of drug resistance, treatment failure, relapse, death and persistent infectiousness remains an impediment to the tuberculosis control programmes. The objective of the study was to identify predictors of default among new smear positive TB patients registered for treatment to suggest possible interventions to set right the problems to sustain and enhance the programme performance.

Methodology & Principal Findings

Twenty districts selected from six states were assigned to six strata formed, considering the geographic, socio-cultural and demographic setup of the area. New smear positive patients registered for treatment in two consecutive quarters during III quarter 2004 to III quarter 2005 formed the retrospective study cohort. Case control analysis was done including defaulted patients as “cases” and equal number of age and sex matched patients completing treatment as “controls”. The presence and degree of association between default and determinant factors was computed through univariate and multivariate logistic regression analysis. Data collection was through patient interviews using pre-tested semi structured questionnaire and review of treatment related records. Information on a wide range of socio demographic and patient related factors was obtained. Among the 687 defaulted and equal numbers of patients in completed group, 389 and 540 patients respectively were satisfactorily interviewed. In the logistic regression analysis, factors independently associated with default were alcoholism [AOR-1.72 (1.23–2.44)], illiteracy [AOR-1.40 (1.03–1.92)], having other commitments during treatment [AOR-3.22 (1.1–9.09)], inadequate knowledge of TB [AOR-1.88(1.35–2.63)], poor patient provider interaction [AOR-1.72(1.23–2.44)], lack of support from health staff [AOR-1.93(1.41–2.64)], having instances of missed doses [AOR-2.56(1.82–3.57)], side effects to anti TB drugs [AOR-2.55 (1.87–3.47)] and dissatisfaction with services provided [AOR-1.73 (1.14–2.6)].

Conclusion

Majority of risk factors for default were treatment and provider oriented and rectifiable with appropriate interventions, which would help in sustaining the good programme performance.     

Poly(vinylpyrrolidone)-doped nitric oxide-releasing xerogels as glucose biosensor membranes

Nitric oxide (NO)-releasing xerogel membranes were prepared as coatings for an electrochemical glucose biosensor to allow for enhanced biocompatibility while maintaining adequate response times and sensitivity. Formation of the NO-donor species was found to drastically decrease the permeability of the aminosilane-based xerogels to both hydrogen peroxide and glucose. The addition of poly(vinylpyrrolidone) (PVP) polymer enhanced the membrane permeability even after exposure to high pressures of NO (necessary for NO-donor synthesis). The analytical response and NO release of PVP-doped NO-releasing xerogels as glucose sensor membranes were further investigated and found to be enhanced via polymer doping. Doping of the polymer into the xerogel did not compromise the stability of the xerogel as evaluated by silicon leaching studies. Despite the addition of PVP, the NO-releasing xerogels maintained reduced bacterial adhesion characteristics analogous to previous reports for NO-releasing xerogels.     

Factors Associated with Mortality and Graft Failure in Liver Transplants: A Hierarchical Approach

Background

Liver transplantation has received increased attention in the medical field since the 1980s following the introduction of new immunosuppressants and improved surgical techniques. Currently, transplantation is the treatment of choice for patients with end-stage liver disease, and it has been expanded for other indications. Liver transplantation outcomes depend on donor factors, operating conditions, and the disease stage of the recipient. A retrospective cohort was studied to identify mortality and graft failure rates and their associated factors. All adult liver transplants performed in the state of São Paulo, Brazil, between 2006 and 2012 were studied.

Methods and Findings

A hierarchical Poisson multiple regression model was used to analyze factors related to mortality and graft failure in liver transplants. A total of 2,666 patients, 18 years or older, (1,482 males; 1,184 females) were investigated. Outcome variables included mortality and graft failure rates, which were grouped into a single binary variable called negative outcome rate. Additionally, donor clinical, laboratory, intensive care, and organ characteristics and recipient clinical data were analyzed. The mortality rate was 16.2 per 100 person-years (py) (95% CI: 15.1–17.3), and the graft failure rate was 1.8 per 100 py (95% CI: 1.5–2.2). Thus, the negative outcome rate was 18.0 per 100 py (95% CI: 16.9–19.2). The best risk model demonstrated that recipient creatinine ≥ 2.11 mg/dl [RR = 1.80 (95% CI: 1.56–2.08)], total bilirubin ≥ 2.11 mg/dl [RR = 1.48 (95% CI: 1.27–1.72)], Na⁺ ≥ 141.01 mg/dl [RR = 1.70 (95% CI: 1.47–1.97)], RNI ≥ 2.71 [RR = 1.64 (95% CI: 1.41–1.90)], body surface ≥ 1.98 [RR = 0.81 (95% CI: 0.68–0.97)] and donor age ≥ 54 years [RR = 1.28 (95% CI: 1.11–1.48)], male gender [RR = 1.19(95% CI: 1.03–1.37)], dobutamine use [RR = 0.54 (95% CI: 0.36–0.82)] and intubation ≥ 6 days [RR = 1.16 (95% CI: 1.10–1.34)] affected the negative outcome rate.

Conclusions

The current study confirms that both donor and recipient characteristics must be considered in post-transplant outcomes and prognostic scores. Our data demonstrated that recipient characteristics have a greater impact on post-transplant outcomes than donor characteristics. This new concept makes liver transplant teams to rethink about the limits in a MELD allocation system, with many teams competing with each other. The results suggest that although we have some concerns about the donors features, the recipient factors were heaviest predictors for bad outcomes.     

The performance of hybrid titania/silica-derived xerogels as active antifouling/fouling-release surfaces against the marine alga Ulva linza: in situ generation of hypohalous acids

Mixed titania/silica xerogels were prepared using titanium tetraisopropoxide (TTIP) and tetraethoxy orthosilicate (TEOS). Xerogel properties were modified by incorporating n-octyltriethoxysilane (C8). The xerogels catalyze the oxidation of bromide and chloride with hydrogen peroxide (H₂O₂) to produce hypohalous acids at pH 7 and pH 8. The antifouling/ fouling-release performance of a TTIP/C8/TEOS xerogel in the presence and absence of H₂O₂ was evaluated for the settlement of zoospores of the marine alga Ulva linza and for the removal of sporelings (young plants). In the absence of H₂O₂, differences in the settlement of zoospores and removal of sporelings were not significant relative to a titanium-free C8/TEOS xerogel. Addition of H₂O₂ gave a significant reduction in zoospore settlement and sporeling removal relative to the C8/TEOS xerogel and relative to peroxide-free conditions. The impact of TTIP on xerogel characteristics was evaluated by comprehensive contact angle analysis, scanning electron microscopy, and X-ray photoelectron spectroscopy.     

Combinatorial Pharmacogenetic Interactions of Bucindolol and β1, α2C Adrenergic Receptor Polymorphisms

Background

Pharmacogenetics involves complex interactions of gene products affecting pharmacodynamics and pharmacokinetics, but there is little information on the interaction of multiple genetic modifiers of drug response. Bucindolol is a β-blocker/sympatholytic agent whose efficacy is modulated by polymorphisms in the primary target (β₁ adrenergic receptor [AR] Arg389 Gly on cardiac myocytes) and a secondary target modifier (α_2C AR Ins [wild-type (Wt)] 322–325 deletion [Del] on cardiac adrenergic neurons). The major allele homozygotes and minor allele carriers of each polymorphism are respectively associated with efficacy enhancement and loss, creating the possibility for genotype combination interactions that can be measured by clinical trial methodology.

Methodology

In a 1,040 patient substudy of a bucindolol vs. placebo heart failure clinical trial, we tested the hypothesis that combinations of β₁389 and α_2C322–325 polymorphisms are additive for both efficacy enhancement and loss. Additionally, norepinephrine (NE) affinity for β₁389 AR variants was measured in human explanted left ventricles.

Principal Findings

The combination of β₁389 Arg+α_2C322–325 Wt major allele homozygotes (47% of the trial population) was non-additive for efficacy enhancement across six clinical endpoints, with an average efficacy increase of 1.70-fold vs. 2.32-fold in β₁389 Arg homozygotes+α_2C322–325 Del minor allele carriers. In contrast, the minor allele carrier combination (13% subset) exhibited additive efficacy loss. These disparate effects are likely due to the higher proportion (42% vs. 8.7%, P = 0.009) of high-affinity NE binding sites in β₁389 Arg vs. Gly ARs, which converts α_2CDel minor allele-associated NE lowering from a therapeutic liability to a benefit.

Conclusions

On combination, the two sets of AR polymorphisms 1) influenced bucindolol efficacy seemingly unpredictably but consistent with their pharmacologic interactions, and 2) identified subpopulations with enhanced (β₁389 Arg homozygotes), intermediate (β₁389 Gly carriers+α_2C322–325 Wt homozygotes), and no (β₁389 Gly carriers+α_2C322–325 Del carriers) efficacy.     

Barnacle settlement and the adhesion of protein and diatom microfouling to xerogel films with varying surface energy and water wettability

Previous work has shown that organosilica-based xerogels have the potential to control biofouling. In this study, modifications of chemistry were investigated with respect to their resistance to marine slimes and to settlement of barnacle cyprids. Adhesion force measurements of bovine serum albumin (BSA)-coated atomic force microscopy (AFM) tips to xerogel surfaces prepared from aminopropylsilyl-, fluorocarbonsilyl-, and hydrocarbonsilyl-containing precursors, indicated that adhesion was significantly less on the xerogel surfaces in comparison to a poly(dimethylsiloxane) elastomer (PDMSE) standard. The strength of adhesion of BSA on the xerogels was highest on surfaces with the highest and the lowest critical surface tensions, γ_C and surface energies, γ_S, and duplicated the ‘Baier curve’. The attachment to and removal of cells of the diatom Navicula perminuta from a similar series of xerogel surfaces were examined. Initial attachment of cells was comparable on all of the xerogel surfaces, but the percentage removal of attached cells by hydrodynamic shear stress increased with γ_C and increased wettability as measured by the static water contact angle, θ_Ws, of the xerogel surfaces. The percentage removal of cells of Navicula was linearly correlated with both properties (R ² = 0.74 for percentage removal as a function of θ_Ws and R ² = 0.69 for percentage removal as a function of γ_C). Several of the aminopropylsilyl-containing xerogels showed significantly greater removal of Navicula compared to a PDMSE standard. Cypris larvae of the barnacle B. amphitrite showed preferred settlement on hydrophilic/higher energy surfaces. Settlement was linearly correlated with θ_Ws (R ² = 0.84) and γ_C (R ² = 0.84). Hydrophilic xerogels should prove useful as coatings for boats in regions where fouling is dominated by microfouling (protein and diatom slimes).     

Determinants of Institutional Delivery among Childbearing Age Women in Western Ethiopia, 2013: Unmatched Case Control Study

Background

Place of delivery is a crucial factor which affects the health and wellbeing of the mother and newborn. Institutional delivery helps the women to access skilled assistance, drugs, equipment, and referral transport. Even though 34% of pregnant women received at least one antenatal care from a skilled provider in Ethiopia by 2013, institutional delivery was 10%. The main objective of the study was to assess determinants of institutional delivery in Western Ethiopia.

Methods

Retrospective unmatched case control study design was used to assess determinants of institutional delivery in Western Ethiopia from September to October 2013. A total of 320 respondents from six districts of East Wollega zone, West Ethiopia were included. Data were collected using pretested and structured questionnaires. Data were entered and cleaned by Epi-info then exported and analyzed using SPSS software. Statistical significance was determined through a 95% confidence level.

Results

Education [Adjusted Odds Ratio (AOR) (95% Confidence Interval (CI)) = 2.754(1.510–8.911)], family size [AOR (95% CI) = .454(.209–.984)], residence [AOR (95% CI) = 3.822 (1.766–8.272)] were important predictors of place of delivery. Four or more antenatal care [(ANC) (AOR (95% CI) = 2.914(1.105–7.682)], birth order [(AOR (95% CI) = .136(.054–.344), age at last delivery [(AOR (95% CI) = 9.995(2.101–47.556)], birth preparedness [AOR (95% CI) = 6.957(2.422–19.987)], duration of labour [AOR (95% CI) = 3.541(1.732–7.239)] were significantly associated with institutional delivery. Moreover service related factors such as distance from health institutions [AOR (95% CI) = .665(.173–.954)], respondents’ awareness of skill of health care professionals [AOR (95% CI) = 2.454 (1.663–6.255)], mode of transportations [AOR (95% CI) = .258(.122–.549)] were significantly associated with institutional delivery.

Conclusions and Recommendations

Policy makers, health service organizations, community leaders and other concerned bodies have to consider the predictors of institutional delivery like education, birth order, antenatal care utilization and residence to improve institutional delivery in the area.     

G-protein coupled receptor solubilization and purification for biophysical analysis and functional studies,in the total absence of detergent

G-protein coupled receptors (GPCRs) constitute the largest class of membrane proteins and are a major drug target. A serious obstacle to studying GPCR structure/function characteristics is the requirement to extract the receptors from their native environment in the plasma membrane, coupled with the inherent instability of GPCRs in the detergents required for their solubilization. In the present study, we report the first solubilization and purification of a functional GPCR [human adenosine A_2A receptor (A_2AR)], in the total absence of detergent at any stage, by exploiting spontaneous encapsulation by styrene maleic acid (SMA) co-polymer direct from the membrane into a nanoscale SMA lipid particle (SMALP). Furthermore, the A_2AR–SMALP, generated from yeast (Pichia pastoris) or mammalian cells, exhibited increased thermostability (∼5°C) compared with detergent [DDM (n-dodecyl-β-D-maltopyranoside)]-solubilized A_2AR controls. The A_2AR–SMALP was also stable when stored for prolonged periods at 4°C and was resistant to multiple freeze-thaw cycles, in marked contrast with the detergent-solubilized receptor. These properties establish the potential for using GPCR–SMALP in receptor-based drug discovery assays. Moreover, in contrast with nanodiscs stabilized by scaffold proteins, the non-proteinaceous nature of the SMA polymer allowed unobscured biophysical characterization of the embedded receptor. Consequently, CD spectroscopy was used to relate changes in secondary structure to loss of ligand binding ([³H]ZM241385) capability. SMALP-solubilization of GPCRs, retaining the annular lipid environment, will enable a wide range of therapeutic targets to be prepared in native-like state to aid drug discovery and understanding of GPCR molecular mechanisms.     

Changing Characteristics of Rotavirus Diarrhea in Children Younger than Five Years in Urban Bangladesh

Background

Childhood rotavirus diarrhea is still one of the major public health challenges. The present study aimed to determine changing characteristics of rotavirus diarrhea in under-5 children at two periods of time.

Methods

We enrolled 5,357 under-5 children with rotavirus positive in two different time periods; i) 1993-1997 (n = 2,493), and ii) 2008–2012 (n = 2,864) considering beginning and ending of two decades. These children were enrolled in the urban Dhaka Hospital of icddr,b.

Results

Overall, proportion of rotavirus was about 25% in 1993–97, which was 42% in 2008–12 (68% rise; p<0.001). Significant higher proportion of children were stunted [38% vs. 22%; aOR-1.33 (95% CI-1.09-1.62)], had vomiting [87% vs. 74%; aOR-2.58 (95% CI-2.02-3.28)], fever [10% vs. 8%; aOR-1.31 (95% CI-0.96-1.78)], family members >5 [38% vs. 35%; aOR-1.32 (95% CI-1.10-1.58)] required more intravenous fluid [9% vs. 3%; aOR-4.93 (95% CI-3.19-7.63)], had higher co-infection with Shigella [3% vs. 1%; aOR-3.36 (95% CI-1.61-7.03)], Vibrio cholerae [4% vs. 1%; aOR-3.70 (95% CI-2.12-6.46)]; and ETEC [13% vs. 7%; aOR-2.21 (95% CI-1.65-2.97)]; however, significantly lower proportion of them used sanitary toilets [54% vs. 78%; aOR-0.66 (95% CI-0.54-0.80)], boiled drinking water [16% vs. 38%; aOR-0.60 (95% CI-0.48-0.74)], used antimicrobial at home [63% vs. 82%; aOR-0.56 (95% CI-0.46-0.69)] and had some or severe dehydration [18% vs. 34%; aOR-0.15 (95% CI-0.12-0.20)] in 1^st observation period compared to that of 2^nd.

Conclusion

Proportion of episodes of under-5 rotavirus diarrhea increased over the period. Concomitant changes in host, socio-demographic and clinical characteristics, and co-infections were also observed. Thus, vaccination campaign which is prevailing in private sector should also be introduced in public sector.     

The Association of Pioglitazone and Urinary Tract Disease in Type 2 Diabetic Taiwanese: Bladder Cancer and Chronic Kidney Disease

Objective

Although studies have shown an association between pioglitazone and bladder cancer, the associated factors have not been identified. The aim of this study was to investigate the factors that may link pioglitazone to bladder cancer.

Materials and Methods

In total, 34,970 study subjects were identified from the National Health Insurance Research Database in 2003 with follow-up from 2005 to 2009. The demographic characteristics of patients who had used and had never used pioglitazone, including age, sex, diabetes duration, urinary tract disease, nephropathy, bladder cancer, and cumulative dose and duration of pioglitazone therapy, were analyzed using the χ2 test. Cox proportional hazard regression models were used to determine the independent effects of pioglitazone on bladder cancer and newly developed chronic kidney disease.

Results

Among 3,497 ever users and 31,473 never users of pioglitazone, the respective incident cases of bladder cancer were 12 (0.4%) and 72 (0.2%), and for newly developed chronic kidney disease 245 (8.1%) and 663 (2.3%), respectively. Ever use of pioglitazone [1.59(1.32–1.91)], cumulative dose of pioglitazone <10,500 mg [1.69 (1.37–2.01)] and >10,500 mg [1.34 (1.04–1.73)], and duration of therapy <12 months [1.68 (1.36–2.08)] and >12 months [1.39 (1.09–1.76)] were associated with the development of chronic kidney disease.

Conclusions

There was no association of pioglitazone use with bladder cancer development, however, there was an association with an increased risk of newly developed chronic kidney disease.     

Mithramycin forms a stable dimeric complex by chelating with Fe(II): DNA-interacting characteristics, cellular permeation and cytotoxicity

Mith (mithramycin) forms a 2:1 stoichiometry drug–metal complex through the chelation with Fe(II) ion as studied using circular dichroism spectroscopy. The binding affinity between Mith and Fe(II) is much greater than other divalent metal ions, including Mg(II), Zn(II), Co(II), Ni(II) and Mn(II). The [(Mith)₂–Fe(II)] complex binds to DNA and induces a conformational change of DNA. Kinetic analysis of surface plasmon resonance studies revealed that the [(Mith)₂–Fe(II)] complex binds to DNA duplex with higher affinity compared with the [(Mith)₂–Mg(II)] complex. A molecular model of the Mith-DNA–Metal(II) complex is presented. DNA-break assay showed that the [(Mith)₂–Fe(II)] complex was capable of promoting the one-strand cleavage of plasmid DNA in the presence of hydrogen peroxide. Intracellular Fe(II) assays and fluorescence microscopy studies using K562 indicated that this dimer complex maintains its structural integrity and permeates into the inside of K562 cells, respectively. The [(Mith)₂–Fe(II)] complex exhibited higher cytotoxicity than the drug alone in some cancer cell lines, probably related to its higher DNA-binding and cleavage activity. Evidences obtained in this study suggest that the biological effects caused by the [(Mith)₂–Fe(II)] complex may be further explored in the future.     

Biliary Endoprosthesis: A Prospective Analysis of Bacterial Colonization and Risk Factors for Sludge Formation

Bacterial colonization of biliary stents is one of the driving forces behind sludge formation which may result in stent occlusion. Major focus of the study was to analyze the spectrum and number of microorganisms in relation to the indwelling time of stents and the risk factors for sludge formation. 343 stents were sonicated to optimize the bacterial release from the biofilm and identified by matrix-associated laser desorption/ionization-time of flight mass spectrometer (MALDI-TOF). 2283 bacteria were analyzed in total. The most prevalent microorganisms were Enterococcus species (spp.) (504;22%), followed by Klebsiella spp. (218;10%) and Candida spp. (188;8%). Colonization of the stents mainly began with aerobic gram-positive bacteria (43/49;88%) and Candida spp. (25/49;51%), whereas stents with an indwelling time>60 days(d) showed an almost equal colonization rate by aerobic gram-negative (176/184;96%) and aerobic gram-positive bacteria (183/184;99%) and a high proportion of anaerobes (127/184;69%). Compared to stents without sludge, more Clostridium spp. [(P = 0.02; Odds Ratio (OR): 2.4; 95% confidence interval (95%CI): (1.1–4.9)]) and Staphylococcus spp. [(P = 0.03; OR (95%CI): 4.3 (1.1–16.5)] were cultured from stents with sludge. Multivariate analysis revealed a significant relationship between the number of microorganisms [P<0.01; OR (95%CI): 1.3(1.1–1.5)], the indwelling time [P<0.01; 1–15 d vs. 20–59 d: OR (95%CI): 5.6(1.4–22), 1–15 d vs. 60–3087 d: OR (95% CI): 9.5(2.5–35.7)], the presence of sideholes [P<0.01; OR (95%CI): 3.5(1.6–7.9)] and the occurrence of sludge. Stent occlusion was found in 70/343(20%) stents. In 35% of cases, stent occlusion resulted in a cholangitis or cholestasis. In conclusion, microbial colonization of the stents changed with the indwelling time. Sludge was associated with an altered spectrum and an increasing number of microorganisms, a long indwelling time and the presence of sideholes. Interestingly, stent occlusion did not necessarily lead to a symptomatic biliary obstruction.     

Hyperactivation of Rhizomucor miehei lipase by hydrophobic xerogels

Although a variety of approaches exist for the immobilization of enzymes, the "science" of enzyme immobilization is still in its infancy. In recent years, considerable interest has developed regarding the use of xerogels for enzyme immobilization. There are several advantages to xerogels for enzyme immobilization, including the opportunity to produce them in defined shapes or thin films and the ability to manipulate their physical characteristics (e.g., porosity, hydrophobicity, and optical properties). In this study we examined the effect of xerogel hydrophobicity on the activity of lipase (EC 3.2.2.3) from Rhizomucor miehei. The hydrophobicity of the xerogels was manipulated by generating xerogels with various molar ratios of propyltrimethoxysilane (PTMS) to tetramethoxysilane (TMOS), from 1:1 to 10:1. The belief was that, by increasing the proportion of propyl groups, the hydrophobicity of the resulting xerogel would be increased. Differences in the hydrophobicity of the resulting xerogels were confirmed using water-affinity studies. Two approaches were taken for water-affinity determinations by examining the ability of the xerogels to remove water from air (controlled humidity) and from water-saturated isopropyl ether. Xerogels with higher propyl content showed a reduced affinity for water. A crude lipase preparation from Rhizomucor miehei was then contacted with sized xerogel particulates and the effect of the xerogel on lipase activity was determined. The presence of the xerogel resulted in hyperactivation of the lipase. Analysis of the protein adsorption revealed changes in the profile of proteins adsorbed to the xerogel based on the hydrophobicity of the xerogel. Based on estimations of the specific activity of the hyperactivated lipase, a minimum hyperactivation of 207% was observed. Part of the hyperactivation may be attributable to xerogel-lipase interactions, but also to the adsorption of a component from the crude lipase preparation that may complex with the lipase and the xerogel producing a stabilizing effect. Further improvements in hyperactivation and selectivity of the xerogels is likely possible by working at lower PTMS:TMOS ratios than those investigated in this study.     

The Gap between Individual Perception and Compliance: A Qualitative Follow-Up Study of the Surgical Safety Checklist Application

Background

“The Surgical Safety Checklist (SSC) is important, but we don’t use it adequately” is a well-suited statement that reflects the SSC''s application in hospitals. Our aim was to follow up on our initial study on compliance (2014) by analysing differences between individual perception and compliance with the SSC.

Methods

We conducted a follow-up online survey to assess healthcare professionals’ individual perception of, as well as satisfaction and compliance with the SSC three years following its thorough implementation.

Results

171 (19.5%) of 875 operating team members completed the online survey. 99.4% confirmed using the SSC. Self-estimated subjective knowledge about the intention of the checklist was high, whereas objective knowledge was moderate, but improved as compared to 2014. According to an independent audit the SSC was used in 93.1% of all operations and among the SSCs used the completion rate was 57.2%. The use of the SSC was rated as rather easy [median (IQR): 7 (6–7)], familiar [7 (6–7)], generally important [7 (7–7)], and good for patients [7 (6–7)] as well as for employees [7 (7–7)]. Only comfort of use was rated lower [6 (5–7)].

Conclusion

There is a gap between individual perception and actual application of the SSC. Despite healthcare professionals confirming the importance of the SSC, compliance was moderate. The introduction of SSCs in the health care sector remains a constant challenge and requires continuous re-evaluation as well as a sensible integration into existing workflows in hospitals.     

Determining the Polymer Threshold Amount for Achieving Robust Drug Release from HPMC and HPC Matrix Tablets Containing a High-Dose BCS Class I Model Drug: In Vitro and In Vivo Studies

It is challenging to achieve mechanically robust drug-release profiles from hydrophilic matrices containing a high dose of a drug with good solubility. However, a mechanically robust drug release over prolonged period of time can be achieved, especially if the viscosity and amount of the polymer is sufficiently high, above the “threshold values.” The goal of this research was to determine the hydroxypropyl cellulose (HPC) and hydroxypropyl methylcellulose (HPMC) polymer threshold amount that would enable robust drug release from matrix tablets containing a high dose of levetiracetam as a class I model drug according to the Biopharmaceutical Classification System (BCS). For this purpose, formulations containing HPC or HPMC of similar viscosity range, but in different amounts, were prepared. Based on the dissolution results, two final formulations were selected for additional in vitro and in vivo evaluation to confirm the robustness and to show bioequivalence. Tablets were exposed to various stress conditions in vitro with the use of different mechanically stress-inducing dissolution methods. The in vitro results were compared with in vivo results obtained from fasted and fed bioequivalence studies. Under both conditions, the formulations were bioequivalent and food had a negligible influence on the pharmacokinetic parameters C_max and area under the curve (AUC). It was concluded that the drug release from both selected formulations is mechanically robust and that HPC and HPMC polymers with intrinsic viscosities above 9 dL/g and in quantities above 30% enable good mechanical resistance, which ensures bioequivalence. In addition, HPC matrices were found to be more mechanically robust compared to HPMC.KEY WORDS: HPC, HPMC, matrix tablets, mechanically robust dissolution, threshold amount     

Perceived Morbidity,Healthcare-Seeking Behavior and Their Determinants in a Poor-Resource Setting: Observation from India

BackgroundTo control the double burden of communicable and non-communicable diseases (NCDs), in the developing world, understanding the patterns of morbidity and healthcare-seeking is critical. The objective of this cross-sectional study was to determine the distribution, predictors and inter-relationship of perceived morbidity and related healthcare-seeking behavior in a poor-resource setting.MethodsBetween October 2013 and July 2014, 43999 consenting subjects were recruited from 10107 households in Malda district of West Bengal state in India, through multistage random sampling, using probability proportional-to-size. Information on socio-demographics, behaviors, recent ailments, perceived severity and healthcare-seeking were analyzed in SAS-9.3.2.ResultsRecent illnesses were reported by 55.91% (n=24600) participants. Among diagnosed ailments (n=23626), 50.92% (n=12031) were NCDs. Respiratory (17.28%,n=7605)), gastrointestinal (13.48%,n=5929) and musculoskeletal (6.25%,n=2749) problems were predominant. Non-qualified practitioners treated 53.16% (n=13074) episodes. Older children/adolescents [adjusted odds ratio for private healthcare providers(AOR_Pri)=0.76, 95% confidence interval=0.71-0.83) and for Govt. healthcare provider(AOR_Govt)=0.80(0.68-0.95)], females [AOR_Govt=0.80(0.73-0.88)], Muslims [AOR_Pri=0.85(0.69-0.76) and AOR_Govt=0.92(0.87-0.96)], backward castes [AOR_Govt=0.93(0.91-0.96)] and rural residents [AOR_Pri=0.82(0.75-0.89) and AOR_Govt=0.72(0.64-0.81)] had lower odds of visiting qualified practitioners. Apparently less severe NCDs [acid-peptic disorders: AOR_Pri=0.41(0.37-0.46) & AOR_Govt=0.41(0.37-0.46), osteoarthritis: AOR_Pri=0.72(0.59-0.68) & AOR_Govt=0.58(0.43-0.78)], gastrointestinal [AOR_Pri=0.28(0.24-0.33) & AOR_Govt=0.69(0.58-0.81)], respiratory [AOR_Pri=0.35(0.32-0.39) & AOR_Govt=0.46(0.41-0.52)] and skin infections [AOR_Pri=0.65(0.55-0.77)] were also less often treated by qualified practitioners. Better education [AOR_Pri=1.91(1.65-2.22) for ≥graduation], sanitation [AOR_Pri=1.58(1.42-1.75)] and access to safe water [AOR_Pri=1.33(1.05-1.67)] were associated with healthcare-seeking from qualified private practitioners. Longstanding NCDs [chronic obstructive pulmonary diseases: AOR_Pri=1.80(1.46-2.23), hypertension: AOR_Pri=1.94(1.60-2.36), diabetes: AOR_Pri=4.94(3.55-6.87)] and serious infections [typhoid: AOR_Pri=2.86(2.04-4.03)] were also more commonly treated by qualified private practitioners. Potential limitations included temporal ambiguity, reverse causation, generalizability issues and misclassification.ConclusionIn this poor-resource setting with high morbidity, ailments and their perceived severity were important predictors for healthcare-seeking. Interventions to improve awareness and healthcare-seeking among under-privileged and vulnerable population with efforts to improve the knowledge and practice of non-qualified practitioners probably required urgently.