Heterogeneous donor circles for fair liver transplant allocation

The United States (U.S.) Department of Health and Human Services is interested in increasing geographical equity in access to liver transplant. The geographical disparity in the U.S. is fundamentally an outcome of variation in the organ supply to patient demand (s/d) ratios across the country (which cannot be treated as a single unit due to its size). To design a fairer system, we develop a nonlinear integer programming model that allocates the organ supply in order to maximize the minimum s/d ratios across all transplant centers. We design circular donation regions that are able to address the issues raised in legal challenges to earlier organ distribution frameworks. This allows us to reformulate our model as a set-partitioning problem. Our policy can be viewed as a heterogeneous donor circle policy, where the integer program optimizes the radius of the circle around each donation location. Compared to the current policy, which has fixed radius circles around donation locations, the heterogeneous donor circle policy greatly improves both the worst s/d ratio and the range between the maximum and minimum s/d ratios. We found that with the fixed radius policy of 500 nautical miles (NM), the s/d ratio ranges from 0.37 to 0.84 at transplant centers, while with the heterogeneous circle policy capped at a maximum radius of 500 NM, the s/d ratio ranges from 0.55 to 0.60, closely matching the national s/d ratio average of 0.5983. Our model matches the supply and demand in a more equitable fashion than existing policies and has a significant potential to improve the liver transplantation landscape.

Hydrophobically modified chitosan biopolymer connects halloysite nanotubes at the oil-water interface as complementary pair for stabilizing oil droplets

The integration of cationic and hydrophobic functionalities into hydrophobically modified chitosan (HMC) biopolymer facilitates complementary emulsion stabilization with negatively charged halloysite clay nanotubes (HNT). Oil-in-water emulsions with smaller droplet sizes and significantly improved interfacial resistance to droplet coalescence are obtained on complementary emulsion stabilization by HNT and HMC compared to the individual emulsifiers alone. Contact angle measurements shows that the adsorption of the cationic HMC onto the negatively charged HNT modifies the surface wettability of the nanotubes, facilitating the attachment of the nanotubes to the oil-water interface. High resolution cryo-SEM imaging reveals that free HMC chains locks the nanotubes together at the oil-water interface, creating a high barrier to droplet coalescence. The emulsion stability is an order of magnitude higher for conditions in which the aqueous HNT dispersion is stabilized by the HMC compared to conditions where the negatively charged HNT is strongly flocculated by the cationic HMC. The hydrophobic interaction between HMC chains, insertion of HMC hydrophobes into the oil phase and electrostatic interactions between HMC and HNT are proposed as key mechanisms driving the increased emulsion stability. For potential application as a dispersant system for crude oil spill treatment, the nanotubular morphology of HNT was further exploited for the encapsulation of the water-insoluble surfactant, sorbitan monooleate (Span 80). The HMC and HNT sterically strengthens the oil-water interfacial layer while release of the Span 80 surfactant from the HNT lumen lowers the oil-water interfacial tension. The concepts advanced here are relevant in the development of environmentally-benign dispersants for oil spill remediation.

Exposure to Toluene Di-isocyanate and Respiratory Effects in Flexible Polyurethane Foam Industries in Western India

Background:

Flexible foam industry largely uses 2,4 and 2,6 Toluene di-isocyanate as main raw materials and chronic exposure to its result in occupational asthma. The exposure to di-isocyanates might be higher due to the usage of obsolete technology, hand-mixing methods and working in confined spaces with insufficient local exhaust ventilation systems in developing countries. Exposure studies in flexible foam industries have not been done in developing countries.

Objective:

The present cross-sectional study was conducted to evaluate toluene di-isocyanate (TDI) exposures and respiratory health of the workers working in the seven flexible polyurethane foam industries located in Western India during 2010-2013.

Method:

A total of 128 personal air samples collected and evaluated for total TDI concentration using improved Occupational Safety and Head Administration method number 42. Then 194 workers were covered for complete clinical examination and spirometry for assessing respiratory health.

Results:

In all, 17.83% of air samples exceeded the ACGIH TWA-TLV of 0.005 ppm for TDI. Though only 11 (5.6%) workers had respiratory complaints, the spirometry revealed that 19 (9.8%) and four (2.1%) had restrictive and obstructive type of pulmonary function impairment, respectively.

Conclusion:

The TWA concentration of TDI exceeded at raw material storage, mixing, foaming, block cutting and curing areas in four out of seven industries even in the presence of local exhaust systems. The respiratory health effect is less when compared to exposure to TDI, suitable preventive and control measures were suggested based on the study findings to the stakeholders to prevent the increase of respiratory health effects.

Effect of kerosene and biomass fuel as cooking medium on pulmonary function of adult nontobacco addict homemaker women residing in slums of Ahmedabad City, Gujarat

Background

Combustion of kerosene and biomass fuel in the kitchen as cooking medium is one of the major sources of indoor air pollution. Such contaminated indoor air quality adversely affects the respiratory health of exposed individuals over a period of time. Homemaker women especially residing in slum areas are always vulnerable to indoor air-pollution-related health hazards.

Objectives

The objective is to assess the relationship between various socio-demographic factors and usage patterns of cooking fuel; and to determine the effect of cooking medium namely biomass, kerosene on pulmonary function parameters.

Methods

A cross-sectional observational study was carried out during April 2012 - April 2016 among 531 nontobacco addicted adult primary homemaker women residing in slums of Ahmedabad city of Gujarat. Basic information-related socio-demographic parameters were collected on a pretested questionnaire. Pulmonary function test (PFT) parameters were evaluated with standard techniques. The statistical analysis was carried out with SPSS software (version 17.0). Statistical tests of significance between groups and mean along with multivariate linear regression analysis were applied.

Results

Predominant cooking medium for nearly 40% of slum households were kerosene and biomass. Mean value of forced expiratory volume in the 1^st s (FEV1) and FEV1/forced vital capacity (FVC) were significantly lower among Kerosene and biomass users compared to LPG users. Multivariate regression analysis with involvement of PFT parameters, cooking medium, and environmental tobacco smoke exposure (ETS) shows, deprivation of both FEV1 and FEV1/FVC were significantly related with the usage of kerosene and biomass; whereas no relation found with ETS.

Conclusion

Reduction of pulmonary function parameters among the study participants were related with kerosene and biomass fuel usage in the kitchen.

Effect of Modified Constrain Induced Movement Therapy on Fatigue and Motor Performance in Sub Acute Stroke

OBJECTIVES

There is a little available information about the fatigue status among people receiving modified constraint induced movement therapy. The study examined such changes. The effect of using restraint on motor performance was also evaluated in sub acute phase after stroke.

MATERIALS AND METHODS

The study was designed as two group pretest and post-test study. The experimental design included a pretest and post test measures of dependent variables fatigue and motor function. All patients were recruited from the Safdurjung Hospital. 20 patients in subacute phase of stroke (3-9 months), (N = 10) mean age±SD 51.90±15.27, MAS score mean ± SD 1.90±.316 and post stroke duration mean ±SD 6.45±2.26 were included in the experimental group and (N = 10) mean age ± SD 54.10±17.42, MAS score mean ±SD 1.52±0.52 and post stroke duration mean±SD score 4.55± 2.52 were included in the control group. The subjects in the experimental group were restrained for six hours every week day with task training for 2 h per day five times a week for three weeks and the subjects in the controlled group received task training for 2 h per day five times a week for three weeks with no restrain. Motor Performance and fatigue were measured on day to day basis by Wolf Motor Function Test Scores (WMFT) and 11th item of Barrow Neurological Institute (BNI) scale in both experimental and controlled group.

RESULTS

The restraint group exhibited significant better motor performance than the controlled group. Mean difference between Pre- WMFT scores and Post WMFT scores were (0.533±.362) as compared to controlled group (0.192±.23). No significant statistical difference was observed in the difference of mean Pre- BNI and Post - BNI scores in either of the two groups (p = .57). Difference between the experimental and controlled group in motor performance and fatigue scores were nonsignificant.

CONCLUSIONS

Restraint improves motor performance in subacute therapy group and the intensive practice associated with m-CIMT may be administered without the exacerbation of fatigue.

Outcomes of Definitive Treatment of Signet Ring Cell Carcinoma of the Rectum: Is Minimal Invasive Surgery Detrimental in Signet Ring Rectal Cancers?

The outcome of surgery for signet ring adenocarcinoma of rectum is suboptimal with high predilection for locoregional and peritoneal metastases. Lack of intercellular adhesion due to focal loss of epithelial cell adhesion molecule (EpCAM) may account for this. In such patients, whether minimal invasive surgery carries a high risk of dissemination by pneumoperitoneum and tumor implantation remains uncertain. The aim of this study was to compare the outcomes of patients undergoing minimally invasive surgery (MIS) versus open surgery in patients with signet ring cell adenocarcinoma of rectum. A retrospective study was conducted at a tertiary care center over 3 years on 39 patients undergoing open surgery and 40 patients undergoing MIS diagnosed with signet ring cell carcinoma (SRCC) identified from our surgical database. Patient characteristics in terms of demographics, clinicoradiological staging, neoadjuvant therapy, and type of surgery with morbidity were compared in the two groups. Data on patients undergoing adjuvant therapy and 3 years disease-free survival (DFS) and overall survival (OS) were analyzed. Recurrence patterns in both groups were separately identified as locoregional, peritoneal, or systemic. The number of patients undergoing surgery in the two arms was 40 (MIS) and 39 (open). In the MIS arm, mean DFS was 29 months whereas in the open arm, it was 25.8 months. The mean OS was 33.65 months for the MIS arm and that for the open arm was 36.34 months. This retrospective study reveals no significant difference in outcomes of surgery for signet ring cell rectal cancers with either MIS or open approach.

GPUPeP: Parallel Enzymatic Numerical P System simulator with a Python-based interface

Membrane computing is a computational paradigm inspired by the structure and behavior of a living cell. P Systems are the computing devices that are used to realize membrane computing models. Numerous theoretical studies on many variants of P Systems have shown them to be computationally universal. There is a wide range of applications of P Systems from modeling of biological processes to image processing. Among many variants of P Systems, one of the most important is Enzymatic Numerical P System (ENPS). ENPS is a class of P System in which membranes operate on numerical values. To realize the power of ENPS there are a few simulators developed. Each and every simulator has some advantages as well as some disadvantages. Here, a GPU based simulator using Python as a user interaction language is developed. This tool is a completely parallel variant, compatible with a Python based sequential simulator (PeP) which was the first Python based work for ENPS. The developed simulator uses CUDA to interact with GPU and gives the desired speed up, while processing the membranes. There are two important case studies which show the performance of the developed tool to be far better than the other serial simulators.

Multi-ENPS simulator support tool with automatic file inter-conversion and multi-membrane execution

P System or Membrane Computing is an unconventional and natural computing model inspired by the functioning of a living cell. This model has an inherently parallel structure. There are several variants of P System developed, each of which has a different application. One of the variants, Enzymatic Numerical P System (ENPS), has primarily been developed to be used with numerical values (as in economics) and thus has vast applications. For realizing ENPS there are several tools available, primarily based on Java and Python, each of which has a different input format. Currently, there is no tool which allows the user to execute ENPS using both the simulators on the same platform, the issue being inter-conversion between input formats, namely, XML and PeP (specific format designed for Python based ENPS). Another major issue with existing simulators is their inability to allow multiple membrane systems to be executed and there is no facility for interconnection between two membrane systems. A tool developed here solves both problems namely, file inter-conversion and multiple membrane support by transferring dependent variable values automatically according to users' choice. The tool is developed using Python 3.0 and has only a few dependencies. The tool is tested under different scenarios and the results confirm the correctness of the tool.

Bandwidth Enhancement of Substrate Integrated Waveguide Cavity-backed Bow-tie-complementary-ring-slot Antenna using a Shorted-via

In this study, a planar cavity-backed bow-tie-complementary-ring-slot antenna is proposed, and a new approach for bandwidth enhancement using a shorted-via is introduced. A shorted-via concept overcomes the narrow impedance bandwidth of a conventional substrate integrated waveguide cavity-backed antenna. By adjusting the location of the shorted-via (placed just above the centroid of the radiating slot), the individual bandwidth of the lower and higher order resonances has been tuned below -10 dB criterion, which results in the broadening of the bandwidth. Finally, the antenna is proficient to operate for an impedance bandwidth of 15.71 per cent, ranging from 12.02~14.07 GHz. The proposed antenna shows a gain of better than 4 dBi within the operating band with less than 0.5 dBi variation. Moreover, the antenna preserves good radiation characteristics, which is similar to that of the conventional metallic counterpart. To validate the simulated results, an antenna is fabricated and tested. The simulated results in terms of the reflection coefficient, gain, and radiation patterns are in good agreement with the measured results.

A Triangular-shaped Quarter-mode Substrate Integrated Waveguide based Antenna for WBAN Applications

<p class="Abstract">In this study, a compact quarter-mode substrate integrated waveguide (QMSIW) based dual-band antenna is proposed for wireless body area network applications. A QMSIW resonator is realised by splitting the full-mode substrate integrated waveguide cavity along the perfect magnetic conductor walls. The proposed antenna preserves the fundamental mode TE110 and the third order mode TE220 of the square SIW cavity. The proposed antenna is linearly polarised in the lower band at 2.45 GHz and circularly polarised in the higher frequency band at 5.8 GHz. The on-body performance of the antenna is validated on a piece of pork muscle tissue and it has been found to be stable with respect to surroundings. The proposed antenna covers the ISM bands 44 MHz (2.445 GHz - 2.489 GHz) and 225 MHz (5.730 GHz - 5.955 GHz) at 2.45 GHz and 5.8 GHz, respectively. The measured gain of the antenna on pork tissue is 1.87 dBi and 5.5 dBi at two bands. In addition, the specific absorption rate is obtained of 0.65 mW/g and 1.51 mW/g at two bands (wext = 2 mm), averaged over 1 g of muscle with 100mW input power. Moreover, the simulated and experimental results demonstrate a good agreement.</p>

Dentists' Attitudes and perceptions toward protective mouthguards

Objectives (Background)

Risk of dental injury from contact sports can be prevented by the use of mouthguards. Dentists provide excellent information regarding mouthguards. Thus, the aim was to assess the awareness among dentists regarding the same, the level of training in fabricating a mouthguard and whether they regularly recommend one for their athletically active patients.

Materials and Methods

This institutional cross-sectional survey was conducted in the Department of Orthodontics, Government Dental College, Kottayam, and Kerala, India. An online form was sent out to 1500 offices and departments in dental institutions through email with a time period of 1 month given to fill responses and was analyzed using descriptive statistics.

Results

A response from 640 was recorded; most of them had not received or had fabricated a mouthguard during their dental training or private practice, even though one-third recommended one to their athletically active patients with a lack of formal training being the reason for not routinely advocating mouthguard usage. Most were aware of more than one type of mouthguards and recommended customized one for the same, however, more than half were not aware of a different type intended for orthodontic patients.

Conclusion

It is not a routine practice currently, among general dentists and specialists alike, in our country, to prescribe a mouthguard. It is time that the dental fraternity spread awareness for the prevention of injuries. A relook into the academic curriculum while advocating the use of customized mouthguards to patients due to contact sports is required.

Association between gestational diabetes mellitus exposure and childhood adiposity is not substantially explained by offspring genetic risk of obesity

AIM

To examine the extent to which offspring obesity-associated genetic risk explains the association between gestational diabetes mellitus and childhood adiposity.

METHODS

We studied 282 children aged 7-12 years who were enrolled in the Exploring Perinatal Outcomes in Children Study. A genetic risk score for BMI was calculated as the count of 91 established BMI-raising risk alleles. Multivariable linear and logistic regression models were used to estimate associations between the offspring genetic risk score and exposure to gestational diabetes and childhood adiposity (BMI and waist circumference), adjusting for clinical and demographic covariates. The contribution of offspring genetic risk to associations between maternal gestational diabetes and childhood outcomes was estimated by comparing the regression coefficients for the gestational diabetes variable in models with and without the genetic risk score.

RESULTS

The offspring BMI genetic risk score was associated with childhood BMI (P = 0.006) and waist circumference (P = 0.02), and marginally with gestational diabetes (P = 0.05). Offspring BMI genetic risk did not contribute significantly to associations between gestational diabetes and childhood BMI [7.7% (95% CI -3.3, 18.8)] or waist circumference [5.8% (95% CI -3.1, 14.8); P = 0.2 for both].

CONCLUSIONS

Offspring obesity genetic risk does not explain a significant proportion of the association between gestational diabetes exposure and childhood adiposity. The association between gestational diabetes and childhood adiposity is probably explained through alternative pathways, including direct intrauterine effects or a shared postnatal environment.

P21-activated kinase 1 (Pak1) signaling influences therapeutic outcome in pancreatic cancer

BACKGROUND

Therapeutic resistance to gemcitabine in pancreatic ductal adenocarcinoma (PDAC) is attributed to various cellular mechanisms and signaling molecules that influence as a single factor or in combination.

DESIGN

In this study, utilizing in vitro p21-activated kinase 1 (Pak1) overexpression and knockdown cell line models along with in vivo athymic mouse tumor xenograft models and clinical samples, we demonstrate that Pak1 is a crucial signaling kinase in gemcitabine resistance.

RESULTS

Pak1 kindles resistance via modulation of epithelial-mesenchymal transition and activation of pancreatic stellate cells. Our results from gemcitabine-resistant and -sensitive cell line models showed that elevated Pak1 kinase activity is required to confer gemcitabine resistance. This was substantiated by elevated levels of phosphorylated Pak1 and ribonucleotide reductase M1 levels in the majority of human PDAC tumors when compared with normal. Delineation of the signaling pathway revealed that Pak1 confers resistance to gemcitabine by preventing DNA damage, inhibiting apoptosis and regulating survival signals via NF-κB. Furthermore, we found that Pak1 is an upstream interacting substrate of transforming growth factor β-activated kinase 1-a molecule implicated in gemcitabine resistance. Molecular mechanistic studies revealed that gemcitabine docks with the active site of Pak1; furthermore, gemcitabine treatment induces Pak1 kinase activity both in vivo and in cell-free system. Finally, results from athymic mouse tumor models illustrated that Pak1 inhibition by IPA-3 enhances the cytotoxicity of gemcitabine and brings about pancreatic tumor regression.

CONCLUSION

To our knowledge, this is the first study illustrating the mechanistic role of Pak1 in causing gemcitabine resistance via multiple signaling crosstalks, and hence Pak1-specific inhibitors will prove to be a better adjuvant with existing chemotherapy modality for PDAC.

Chemical vapor deposition of MoS2 layers from Mo–S–C–O–H system: thermodynamic modeling and validation

To determine growth windows for CVD of contamination-free layered MoS₂, thermodynamic modelling and experimental validation of the Mo–S–C–O–H system are conducted.

Misoprostol for primary versus secondary prevention of postpartum haemorrhage: a cluster-randomised non-inferiority community trial

OBJECTIVE

To assess whether secondary prevention, which preemptively treats women with above-average postpartum bleeding, is non-inferior to universal prophylaxis.

DESIGN

A cluster-randomised non-inferiority community trial.

SETTING

Health sub-centres and home deliveries in the Bijapur district of Karnataka, India.

POPULATION

Women with low-risk pregnancies who were eligible for delivery with an Auxiliary Nurse Midwife at home or sub-centre and who consented to be part of the study.

METHODS

Auxiliary Nurse Midwifes were randomised to secondary prevention using 800 mcg sublingual misoprostol administered to women with postpartum blood loss ≥350 ml or to universal prophylaxis using 600 mcg oral misoprostol administered to all women during the third stage of labour.

MAIN OUTCOME MEASURES

Postpartum haemoglobin ≤7.8 g/dl, mean postpartum blood loss and postpartum haemoglobin, postpartum haemorrhage rate, transfer to higher-level facilities, acceptability and feasibility of the intervention.

RESULTS

Misoprostol was administered to 99.7% of women as primary prevention. In secondary prevention, 92 (4.7%) women had postpartum bleeding ≥350 ml, of which 90 (97.8%) received misoprostol. The proportion of women with postpartum haemoglobin ≤7.8 g/dl was 5.9 and 8.8% in secondary and primary prevention clusters, respectively [difference -2.9%, one-sided 95% confidence interval (CI) <1.3%]. Postpartum transfer and haemorrhage rates were low (<1%) in both groups. Shivering was more common in primary prevention clusters (P = 0.013).

CONCLUSION

Secondary prevention of postpartum haemorrhage with misoprostol is non-inferior to universal prophylaxis based on the primary outcome of postpartum haemoglobin. Secondary prevention could be a good alternative to universal prophylaxis as it medicates fewer women and is an acceptable and feasible strategy at the community level.

TWEETABLE ABSTRACT

Secondary prevention of postpartum haemorrhage with misoprostol is non-inferior to universal prophylaxis.

Electrochemical investigations of stable cavitation from bubbles generated during reduction of water

Megasonic cleaning is traditionally used for removal of particles from wafer surfaces in semiconductor industry. With the advancement of technology node, the major challenge associated with megasonic cleaning is to be able to achieve high cleaning efficiency without causing damage to fragile features. In this paper, a method based on electrochemistry has been developed that allows controlled formation and growth of a hydrogen bubbles close to a solid surface immersed in an aqueous solution irradiated with ∼1 MHz sound field. It has been shown that significant microstreaming from resonating size bubble can be induced by proper choice of transducer duty cycle. This method has the potential to significantly improve the performance of megasonic cleaning technology through generation of local microstreaming, interfacial and pressure gradient forces in close vicinity of conductive surfaces on wafers without affecting the transient cavitation responsible for feature damage.

Amniotic fluid volume changes in response to frusemide induced maternal fluid shifts

Frusemide use in pregnancy is generally restricted to patients with cardiac decompensation. In the past, maternal administration of oral frusemide had been tried to identify non-functioning fetal kidneys by utilizing the diuretic effect of frusemide on the fetal kidneys. We report a case of primigravida with severe mitral stenosis presenting in pulmonary edema that received high dose of frusemide. This was associated with the development of transient oligohydramnios. We discuss the clinical significance of this observation and the possible explanations.

Infliximab inhibits activation and effector functions of peripheral blood T cells in vitro from patients with clinically active ulcerative colitis

Many patients with inflammatory bowel disease (IBD) are undergoing therapy with infliximab, an antibody specific for TNF. However, the exact mechanisms of action of infliximab are not completely understood. The aim of this study was to determine the in vitro effects of infliximab on blood T cells derived from anti-TNF therapy-naïve ulcerative colitis (UC) patients with clinically active disease. Peripheral blood mononuclear cells were stimulated polyclonally or by antigen in the presence or absence of infliximab. The T cell phenotype was investigated by flow cytometry, cytokine secretion was determined by ELISA, and cell proliferation was determined by thymidine assay or CFSE dye. Presence of infliximab resulted in reduced expression of CD25 in CD4(+) and CD8(+) T cell populations and inhibited secretion of IFN-γ, IL-13, IL-17A, TNF as well as granzyme A. Infliximab also suppressed CD4(+) and CD8(+) T cell proliferation. These effects of infliximab were recorded both in T cells activated by polyclonal and antigen-specific stimulation. The effects of infliximab on T cell apoptosis and induction of FOXP3(+) CD4(+) T regulatory cells were ambiguous and depended on the originating cellular source and/or the stimulation mode and strength. In conclusion, infliximab is able to reduce T cell activation as measured by CD25, proliferation and cytokine secretion in vitro from UC patients with clinically active disease. These data suggest that suppression of T cell activity may be important for infliximab-mediated disease remission in patients with UC.

Adhesion molecules, endothelin-1 and lung function in seven population-based cohorts

CONTEXT

Endothelial function is abnormal in chronic obstructive pulmonary disease (COPD); whether endothelial dysfunction causes COPD is unknown.

OBJECTIVE

Test associations of endothelial biomarkers with FEV1 using instrumental variables.

METHODS

Among 26 907 participants with spirometry, ICAM-1, P-selectin, E-selectin and endothelin-1 were measured in subsets.

RESULTS

ICAM-1 and P-selectin were inversely associated with FEV1 among European-Americans (-29 mL and -34 mL per standard deviation of log-transformed biomarker, p < 0.001), as was endothelin-1 among African-Americans (-22 mL, p = 0.008). Genetically-estimated ICAM-1 and P-selectin were not significantly associated with FEV1. The instrumental variable for endothelin-1 was non-informative.

CONCLUSION

Although ICAM-1, P-selectin and endothelin-1 were inversely associated with FEV1, associations for ICAM-1 and P-selectin do not appear causal.

Effect of non-ionic surfactants on transient cavitation in a megasonic field

High resolution chronoamperometry has been used to characterize the effect of two non-ionic surfactants, Triton® X-100 and NCW®-1002, on cavitation in aqueous solutions exposed to ~1 MHz sound field. Specifically, using ferricyanide as the electroactive species, temporal variation of current during its reduction on a 25 μm Pt microelectrode has been measured and is used to elucidate transient cavity behavior. The chronoamperograms for solutions exposed to megasonic field show current 'peaks' riding on the baseline current. These current 'peaks' have been attributed to the diffusion of ferricyanide species concentrated at the liquid-vapor interface of a transient cavity at the end of its collapse. In the presence of surfactants, the frequency of occurrence of current 'peaks' with magnitude ≥ 0.3 μA is found to increase indicating a higher number of transient cavity collapses. A simple mathematical model based on diffusion developed previously by the authors has been used to extract the maximum cavity size and range of distances between the center of the collapsing cavity and the electrode surface in the surfactant solutions.

Umbilical coiling index as a marker of perinatal outcome: an analytical study

Objectives. To measure umbilical coiling index (UCI) postnatally and to study the association of normocoiling, hypocoiling and hypercoiling to maternal and perinatal outcome. Method(s). One thousand antenatal women who went into labour were studied and umbilical coiling index calculated at the time of delivery. UCI was determined by dividing the total number of coils by the total umbilical cord length in centimeters. Its association with various maternal and perinatal risk factors were noted. The statistical tests were the Chi-square test and assessed with SPSS version 13.0 software and statistically analyzed. P value of less than 0.05 was regarded as statistically significant. Results. The mean umbilical coiling index was found to be 0.24 ± 0.09. Hypocoiling (<0.12) was found to be significantly associated with hypertensive disorders, abruptio placentae, preterm labour, oligohydramnios, and fetal heart rate abnormalities. Hypercoiling (>0.36) was found to be associated with diabetes mellitus, polyhydramnios, cesarean delivery, congenital anomalies, and respiratory distress of the newborn. Conclusion. Abnormal umbilical coiling index is associated with several antenatal and perinatal adverse features.

Genetic polymorphism of NAT2 metabolizing enzymes on phenytoin pharmacokinetics in Indian epileptic patients developing toxicity

OBJECTIVE

To investigate the effects of NAT2 metabolizing enzymes on the pharmacokinetics of antiepileptic drug phenytoin in the epileptic patients showing toxicity.

METHODS

Fifty epileptic individuals who had developed toxicity to phenytoin and 50 control epileptic subjects who had not developed toxicity to phenytoin were genotyped for NAT2 (NAT2*5A, NAT2*5C, NAT2*7, NAT2*6) polymorphisms by polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP method). Phenytoin plasma levels were analyzed by reversed phase HPLC method and pharmacokinetic parameters such as area under the concentration curve (AUC), maximum concentration (C(max)), time to C(max) (t(max)) and half-life (t(1/2)) were estimated by noncompartmental analysis using PK Solutions® software.

RESULTS

The NAT2 polymorphism was seen to be in Hardy-Weinberg equilibrium and showed significant genotypic as well as allelic association with phenytoin toxicity for NAT2*5A (481C>T) and NAT2*5C (803A>G). Pharmacokinetic parameters for phenytoin in toxicity group of poor metabolizers showed a longer elimination half-life of a drug (t(1/2) = 35.3 h) and less clearance rate (CL = 468 mL/h) compared to intermediate metabolizers (t(1/2) = 33.2 h, CL = 674 mL/h) and extensive metabolizer (t(1/2) = 20.7 h, CL = 977 mL/h) in NAT2*5A polymorphism.

CONCLUSION

Our findings suggest that the NAT2*5A genetic polymorphisms plays a significant role in the steady-state concentrations of phenytoin and thereby have impact on toxicity in epileptic patients.

Multinomial logistic regression model to assess the levels in trans, trans-muconic acid and inferential-risk age group among benzene-exposed group

There are only a few studies performed on multinomial logistic regression on the benzene-exposed occupational group. A study was carried out to assess the relationship between the benzene concentration and trans-trans-muconic acid (t,t-MA), biomarkers in urine samples from petrol filling workers. A total of 117 workers involved in this occupation were selected for this current study. Generally, logistic regression analysis (LR) is a common statistical technique that could be used to predict the likelihood of categorical or binary or dichotomous outcome variables. The multinomial logistic regression equations were used to predict the relationship between benzene concentration and t,t-MA. The results showed a significant correlation between benzene and t,t-MA among the petrol fillers. Prediction equations were estimated by adopting the physical characteristic viz., age, experience in years and job categories of petrol filling station workers. Interestingly, there was no significant difference observed among experience in years. Petrol fillers and cashiers having a higher occupational risk were in the age group of ≤24 and between 25 and 34 years. Among the petrol fillers, the t,t-MA levels with exceeding ACGIH TWA-TLV level was showing to be more significant. This study demonstrated that multinomial logistic regression is an effective model for profiling the greatest risk of the benzene-exposed group caused by different explanatory variables.

Short communication: association of HLA-A*1101 with resistance and B*4006 with susceptibility to HIV and HIV-TB: an in silico analysis of promiscuous T cell epitopes

We have shown the association of HLA-A*11 with resistance and HLA-B*40 and -DR2 with susceptibility to HIV and HIV-TB. In the present study, we performed high-resolution subtyping of HLA-A*11 and -B*40 to identify the subtype level association, using the polymerase chain reaction-based sequence-specific oligonucleotide probe method. Underrepresentation of HLA-A*1101 was observed in overall HIV [p(c) = 0.012, OR 0.42 (95% confidence interval (CI) 0.24-0.72)] and HIV(+)TB(+) [p(c) = 0.001, OR 0.18 (95% CI 0.06-0.46)] compared to healthy controls. Significantly higher frequencies of HLA-B*4006 were observed in overall HIV [p = 0.0001, p(c) = 0.004, OR 2.71 (95% CI 1.58-4.75)], HIV(+)TB(-) [p = 0.0003, p(c) = 0.008, OR 2.82 (95% CI 1.56-5.17)], and HIV(+)TB(+) [p = 0.003, p(c) = 0.086, OR 2.56 (95% CI 1.33-4.95)] compared to healthy controls. An in silico analysis of potential T cell epitopes of consensus Gag and Pol sequences of HIV-1 subtype C Indian strains revealed relatively higher number of promiscuous HLA-B40, HLA-DRB1*1501, and -DRB1*1502 (HLA-DR2)-restricted epitopes in contrast to limited numbers of promiscuous binders restricted by HLA-A*1101. The results suggest that HLA-A*1101 may be associated with protection against HIV and the development of TB in HIV patients while HLA-B*4006 may be associated with susceptibility to HIV and TB development in HIV patients. The present study also suggests that the extent of promiscuity of T cell epitopes of HIV-1 subtype C restricted by HLA alleles exerting opposing effects might differ.

CCR2, MCP-1, SDF-1a & DC-SIGN gene polymorphisms in HIV-1 infected patients with & without tuberculosis

BACKGROUND & OBJECTIVES

Variability in the clinical outcome of persons exposed to and infected with HIV-1 and tuberculosis (TB) is determined by multiple factors including host genetic variations. The aim of the present study was to find out whether chemokine, chemokine receptor and DC-SIGN gene polymorphisms were associated with susceptibility or resistance to HIV and HIV-TB in south India.

METHODS

CCR2 V64I (G/A), monocyte chemoattractant protein-1 (MCP-1) -2518 A/G, stromal cell derived factor-1alpha; (SDF-1alpha) 3'UTR G/A and DC-SIGN gene polymorphisms were studied by polymerase chain reaction based methods in HIV-1 infected patients without TB (n=151), with pulmonary TB (PTB) (n=81) and extrapulmonary TB (n=31), 155 PTB patients without HIV and 206 healthy controls.

RESULTS

The genotype frequencies of CCR2 V64I, MCP-1 -2518 and DC-SIGN polymorphisms did not differ significantly between the study groups. A significantly increased frequency of GG genotype of SDF-1alpha polymorphism was observed among HIV+PTB+ patients compared to healthy controls (P=0.009, Pc=0.027).

INTERPRETATION & CONCLUSIONS

Our data suggest that GG genotype of SDF-1alpha 3'UTR polymorphism may be associated with susceptibility to PTB in HIV-1 infected patients. A better understanding of genetic factors that are associated with TB could help target preventive strategies to those HIV patients likely to develop tuberculosis.

Haplotype analysis of HLA-A, -B antigens and -DRB1 alleles in south Indian HIV-1-infected patients with and without pulmonary tuberculosis

We have shown earlier the association of human leucocyte antigen (HLA)-A11 with resistance and HLA-B40 and -DR2 with susceptibility to HIV and HIV-TB. In the present study, we have attempted to find out the HLA-DR2 subtypes and the possible HLA-A/-B/-DRB1 haplotype combinations that are associated with susceptibility or resistance to HIV and HIV with pulmonary tuberculosis (HIV+PTB+). HLA-DR2 subtyping was carried out by polymerase chain reaction-based sequence-specific oligonucleotide probe method. Overrepresentation of HLA-DRB1*1501 in HIV-positive PTB-negative (HIV+PTB-) patients (P = 0.004, P(c) = 0.06) and -DRB1*1502 in HIV-positive PTB-positive (HIV+PTB+) patients (P = 0.019) was observed as compared to healthy controls. Haplotype analysis revealed an increased frequency of HLA-A2-DRB1*1501 haplotype in HIV+PTB- patients (P = 0.008) and HLA-A2-DRB1*1502 among HIV+PTB+ patients (P = 0.01) compared to healthy controls. The haplotypes B40-DRB1*1501 and B40-DRB1*04 were found to be moderately increased in HIV+PTB(-) and HIV+PTB+ patients (P < 0.05). The study suggests that HLA-A2-DRB1*1501 haplotype may be associated with HIV infection while HLA-A2-DRB1*1502 haplotype might be associated with susceptibility to PTB in HIV patients. Moreover, HLA-B40-DRB1*1501 and HLA-B40-DRB1*04 haplotypes may be associated with susceptibility to HIV infection and to PTB in HIV patients.

Function of beta1 integrin in oral epithelia and tooth bud morphogenesis

Integrin beta1 is critical for basement membrane organization and hair follicle morphogenesis in the skin epidermis; however, less is known about its function in the developing oral epithelium. Since the skin and oral epithelia share structural similarity, we hypothesized that beta1 integrin function would be critical for the normal development of oral epithelium and tooth buds. The conditional (oral mucosa-specific) beta1 integrin knockout (KO) mice displayed severe disruption of the basement membrane of the tongue epithelium and developing tooth buds. Interestingly, unlike the developing hair follicles, early morphological development of the KO molar tooth buds was normal. However, subsequent morphogenetic events, such as cusp formation, cervical loop down-growth, and ameloblast polarization, did not occur normally. Primary KO oral keratinocytes showed defective cell spreading and robust focal adhesions. Our studies indicate that beta1 integrin plays an essential role in the normal development of the oral epithelium and its appendages.

FOXP3 expression in blood, synovial fluid and synovial tissue during inflammatory arthritis and intra-articular corticosteroid treatment

OBJECTIVE

To analyse the distribution of FOXP3+CD25+CD4+ regulatory T cells (Treg) in peripheral blood, synovial fluid and tissue of patients with rheumatic disease during relapse and after local treatment.

METHODS

FOXP3 expression was assessed by flow cytometry, immunohistochemistry, immunofluorescence and real-time polymerase chain reaction (RT-PCR). The functional suppressive capacity of Treg was analysed after co-culture with effector CD4+CD25- T cells through assessment of proliferation and cytokine secretion.

RESULTS

It was shown that FOXP3 protein and mRNA expression in synovial fluid T cells was not confined solely to CD25(bright) T cells as seen in blood, but included CD25(intermediate) and even CD25(neg) T cells. Indeed, synovial fluid CD25(high) T cells showed similar suppressive capacity as CD25(bright) T cells, indicating the presence of functional Treg in T cells with lower intensity of CD25. In synovial tissue, FOXP3+ cells were present in low numbers within T-cell infiltrates and decreased further after intra-articular glucocorticosteroid administration, in parallel with the general reduction in inflammation.

CONCLUSIONS

Identification of synovial fluid FOXP3+ Treg with varying intensities of CD25 opens up possibilities for thorough characterisation of this important T-cell subset in the inflammatory compartment. However, only scarce synovial membrane expression of FOXP3 was found even in the absence of overt inflammation, suggesting that the synovial membrane is a site that would benefit therapeutically from Treg expansion.