Mechanical characterization of nanoporous materials by use of atomic force acoustic microscopy methods

We have used the atomic force acoustic microscopy (AFAM) method to determine the indentation modulus of nanoporous thin-film materials with ultralow values of dielectric permittivity (dielectric constant k < 2.4). The AFAM method is based on the contact mode of atomic force microscopy (AFM) and as such is able to characterize materials with high spatial resolution. The tested material was porous organosilicate glass with nominal porosity ranging from 27% to 40%. The values obtained for the indentation modulus varied from 4 to 7 GPa depending on the pore concentration. The values obtained for the indentation modulus by use of the AFAM method were in very good agreement with those determined by nanoindentation. In addition, a part of the AFAM results obtained for the sample with the highest porosity content showed dependence of the effective indentation modulus on the applied load. Preliminary data analysis suggests that the stress rate is the critical factor in triggering this particular mechanical response of the porous material.

The short-term impact of protocol biopsies in a live-related renal transplant program using tacrolimus based immunosuppression

The aim of the study was to assess the impact of protocol biopsies in a live-related renal transplant program using tacrolimus-based immunosuppression in the short term. Eighty-three live-related transplant recipients were randomly allocated to protocol biopsy group (Group I, n = 40) and a control group (Group II, n = 43). Other immunosuppressants in these groups consisted of either mycophenolate mofetil or azathioprine and steroids. Protocol biopsies were conducted in biopsy group at 1, 6, and 12 months post-transplant. The non-biopsy group was followed by serial serum creatinine and biopsies in them were conducted as and when clinically indicated. Both groups were analyzed at 12 months with respect to graft function and survival. The two groups were similar with respect to age, number of dialysis pre-operatively, tacrolimus levels, induction therapy, donor age, and donor glomerular filtration rate. Forty protocol biopsies were conducted at 1 month, 31 at 6 months, and 26 at 12 months. The prevalence of sub-clinical rejection at 1, 6, and 12 months in these biopsies was 17.5%, 11.2%, and 10.3%, respectively. The prevalence of calcineurin inhibitor toxicity during same period was 15%, 15.5%, and 14.4%, respectively. The cumulative rejection rate in Group I and Group II at 12-month follow-up was 10.3% and 11.3% (P = 0.78), respectively, and cumulative calcineurin inhibitor toxicity at 12 months was 14.4% and 9.3% (P = 0.59), respectively, were not statistically significant. There was no difference in graft survival and function at 1 year. Protocol biopsies have a limited role in a well-matched renal transplant program with tacrolimus-based immunosuppression in the short term. However, the long-term impact of protocol biopsies needs further evaluation.

Prevalence of chronic kidney diseases and its determinants among perimenopausal women in a rural area of North India: A community-based study

The burden of noncommunicable diseases is rising in India. A high prevalence of lifestyle-related diseases in perimenopausal women in the community makes them vulnerable to chronic kidney diseases (CKD). A cross-sectional community-based study was carried out among women >35 years of age in the village of Ballabgarh, Haryana (north India). Eligible women were selected by the probability proportionate to size sampling method. Estimation of glomerular filtration rate (GFR) was carried out by using the age- and body surface area (BSA)-adjusted Cockcroft–Gault (CG) and modification of diet in renal disease (MDRD) equations. Association of risk factors such as obesity, hyperlipidemia, hypertension, and diabetes mellitus with CKD was also assessed using multivariate logistic regression analysis. A total of 455 women were studied. The prevalence of low GFR (<60 mL/min/1.73 m²) by the CG/BSA equations and MDRD equation was found to be 18.2% (95% confidence interval 14.6, 21.8) and 5.9% (95% confidence interval 3.7, 8.1), respectively. Obesity (odds ratio 15.5) (P = 0.002), hyperlipidemia (odds ratio: 2.5) (P = 0.017), and age (P < 0.001) were significantly associated with reduced GFR on multivariate logistic regression analysis. This study observed a high prevalence of CKD and its risk factors among perimenopausal women in a rural community in north India. The study highlights the need of a multipronged, community-based intervention strategy that includes a high-risk screening approach and awareness generation about CKD and its risk factors in the community.

Abstract P4-02-02: Comparison of 18F-FDG PET-CT and 11C-MET PET-CT for assessment of response to neoadjuvant chemotherapy in locally advanced breast carcinoma

INTRODUCTION: Neo-adjuvant chemotherapy plays an important role in treatment of breast cancer by decreasing the tumor load & it offers an opportunity to evaluate response of primary tumor to chemotherapy. This makes response monitoring crucial in the management of breast carcinoma. Standard anatomical imaging modalities are unable to accurately reflect the response to chemotherapy until several cycles of drug treatment have been completed. Metabolic imaging using tracers like 18F-fluorodeoxyglucose (FDG) as a marker of glucose metabolism or amino acid tracers like L-methyl-11C methionine (MET) have potential role for the measurement of treatment response in breast cancer.

AIMS AND OBJECTIVES: To compare FDG PET-CT with MET PET-CT for assessment of response to neoadjuvant chemotherapy, in locally advanced breast carcinoma and to correlate it with clinico-pathological response.

METHODS: In our prospective study, 20 patients with histology proven locally advanced breast carcinoma were enrolled. All patients underwent clinical assessment and PET-CT imaging using FDG and MET before and after 3 cycles of neoadjuvant chemotherapy (CAF regimen). Thereafter, all patients were taken for modified radical mastectomy and the resected breast with dissected axillary nodes was sent for histo-pathological analysis. Tumor response to the neoadjuvant chemotherapy was evaluated clinically using WHO criteria and by PET-CT imaging using PERCIST criteria. Responses calculated were compared for statistical significance using paired t- test.

RESULTS: Mean SUV in FDG-PET for primary tumor (p &lt; 0.001) and axilla (p = 0.001) were significantly higher than in MET-PET. After three cycles of chemotherapy, clinical size of the primary tumor decreased by 55.76%, mean SUVmax of the primary lesion decreased by 47.21% in FDG-PET (p = 0.16) and by 45.5% in MET-PET (p = 0.167).

Ring chromosome 22: a review of the literature and first report from India

Ring chromosome 22 [r(22)], a rare cytogenetic finding, has been described in nearly 70 cases to date. Cytogenetic investigations were carried out on a 5-year-old male child with microcephaly and intellectual disability. Cytogenetic investigations revealed his karyotype to be 46,XY,r(22). To the best of our knowledge, this is the first report of an r(22) anomaly from India.

Tuberculosis cutis orificialis (TBCO): a rare manifestation of tuberculosis

Tuberculosis of the oral cavity is a very rare disease and accounts for less than one percent of all cases of tuberculosis. Primary lesions are extremely rare. Presentation is as a single ulcer, may be painful, however multiple painless ulcers have been described. Tongue is the most common oral site involved. The palate, buccal mucosa, floor of the mouth, gingiva, and lips are other possible sites. We hereby report a case of TBCO, a very rare manifestation of tuberculosis.

Oxidative stress, endothelial function, carotid artery intimal thickness and their correlates among chronic peritoneal dialysis patients

We evaluated important nontraditional cardiovascular risk factors, endothelial function and oxidative stress (OS) among stable peritoneal dialysis (PD) patients. Their association with carotid intimal medial thickness (CIMT) was also assessed. Thirty-eight adult patients (13 diabetics, 20 males) on PD for >6 months and 15 age and sex-matched controls were studied. Duration of dialysis (DOD), residual urine output (UO), weekly Kt/V urea, detailed biochemical and lipid profile were noted. OS was measured by serum concentration of antioxidants; vitamin C and ferric reducing ability of plasma (FRAP) and pro-oxidant; thiobarbituric acid-reactive substances (TBARS). High-resolution ultrasonography was used to determine CIMT and flow-mediated dilatation of brachial artery [endothelium-dependent dilatation (EDD)] and dilatation subsequent to nitrate spray [endothelium-independent dilatation (EID)]. Mean age, DOD, UO and Kt/V of study population were 49.3 ± 11.6 years, 19.4 ± 11.8 months, 508.2 ± 422.9 ml/day and 1.73 ± 0.24, respectively. As compared to controls PD patients had higher CIMT (0.46 ± 0.05 vs 0.50 ± 0.07 mm, P = 0.003) and TBARS (1.5 ± 0.4 vs 5.1 ± 2.3 nM/ml, P < 0.001) but lower Vitamin C (1.7 ± 0.3 vs 0.6 ± 0.2 mg%, P < 0.001), FRAP (990.8 ± 78.1 vs 328.7 ± 183.5 μM/L, P < 0.001) and EDD (26.2 ± 5.4 vs 9.8 ± 4.6 %, P < 0.001). TBARS correlated positively with DOD and negatively with hemoglobin. Vitamin C and FRAP correlated positively with serum albumin. EDD correlated positively with UO, Kt/V and hemoglobin. CIMT correlated negatively with Kt/V and hemoglobin. Among themselves CIMT correlated negatively with EDD and vitamin C. EDD correlated positively with vitamin C, while FRAP correlated positively with vitamin C and negatively with TBARS. PD patients have higher OS, poorer endothelial function and higher structural atherosclerosis. These parameters are closely linked to each other, hemoglobin, DOD, residual UO, serum albumin and small solute clearances.

The quality of life of women volunteering as live-related kidney donors in India

BACKGROUND

Women outnumber men 6:1 as live-related donors in our renal transplant programme. Women donors in developing regions are often illiterate and unemployed. This study was done to assess the change in quality of life of women who donate kidneys.

METHODS

We prospectively studied 73 consecutive women volunteering as live-related kidney donors over a 6-month period using the World Health Organization Quality of Life Brief (WHO QoL Bref) Questionnaire and Hospital Anxiety and Depression Scale (HADS). Each woman was interviewed 2 weeks before and 6 months after kidney donation.

RESULTS

There was a significant improvement in all the domains, namely physical (p=0.0001), psychological (p<0.0001), social relationship (p=0.037) and environment (p<0.0001) of the WHO QoL Bref questionnaire. Donors who were mothers had a greater improvement in all 4 domains than donors with other relationships. There was a significant decrease in the depression score (p<0.0001), but no change in the anxiety scores (p=0.065) following kidney donation. All donors would donate again, if possible.

CONCLUSION

In live-related women kidney donors, quality of life improves and depression scores decline after kidney donation.

Tuberculin skin test for the diagnosis of latent tuberculosis during renal replacement therapy in an endemic area: A single center study

Patients on renal replacement therapy (RRT) are at-risk for developing tuberculosis (TB). There is limited information on tuberculin skin test (TST) and its predictability for development of TB. In this prospective cohort study, patients taken for RRT were included. Patients with active TB were excluded. TST was done with 5-tuberculin unit. In addition to TST, age, sex, diabetes as basic disease, number of dialysis and blood transfusion (BT), pre-transplant TB, hepatitis B and C infections and type of immunosuppression were correlated with the development of TB. Of the 200 patients included, TST was positive in 21 and negative in 179. In TST negative group, 20 (11.1%) and in TST positive group 5 (23.8%) patients developed TB. TB free survival in two groups was similar (P = 0.08). On multivariate Cox regression analysis, hazard of development of TB by TST was 2.7 [P = 0.11, confidence interval (CI) 0.78-9.7]. There was no difference between TST non-responsive and TST negative patients (P = 0.18). Sensitivity and specificity of TST for predicting TB was only 20 and 9%, respectively. Our study shows that TST in patients on dialysis is an insensitive and nonspecific test to predict development of active TB.

Stem cells and lung diseases

This paper is designed to review our current understanding of the role of stem and progenitor cells in lung repair after injury and to review the current status of cell therapy approaches for lung diseases. It was found that circulating EPCs (endothelial progenitor cells) play roles in both acute lung injury and in fibrotic lung diseases. Circulating fibrocytes can contribute to the pathophysiology of fibrotic lung diseases and thus may be a potential therapeutic target. MSCs (mesenchymal cells) suppress lung injury and inflammation in several mouse models of inflammatory and immune-mediated lung diseases. In addition, novel areas of investigation have developed that include increasing exploration of three-dimensional culture systems and bioengineering approaches to generate functional lung tissue ex vivo and in vivo.

Enhancing solar cells with localized plasmons in nanovoids

Localized plasmon resonances of spherical nanovoid arrays strongly enhance solar cell performance by a factor of 3.5 in external quantum efficiency at plasmonic resonances, and a four-fold enhancement in overall power conversion efficiency. Large area substrates of silver nanovoids are electrochemically templated through self-assembled colloidal spheres and organic solar cells fabricated on top. Our design represents a new class of plasmonic photovoltaic enhancement: that of localized plasmon-enhanced absorption within nanovoid structures. Angularly-resolved spectra demonstrate strong localized Mie plasmon modes within the nanovoids. Theoretical modelling shows varied spatial dependence of light intensity within the void region suggesting a first possible route towards Third Generation plasmonic photovoltaics.

Primary antiphospholipid antibody syndrome presenting with adrenal insufficiency in a child: Case report and review of literature

A 7-year-old boy presented with adrenal insufficiency. He subsequently developed venous thrombosis in the limbs and was diagnosed with primary antiphospholipid syndrome (PAPS) based on clinical and laboratory parameters. Both adrenals were normal on imaging. He required thrombolysis and anticoagulation. The progressive course of PAPS was controlled with methylprednisolone. There are few reports of PAPS in pediatric patients, and associated adrenal involvement is rare. The unusual presentation, course and management of the patient and of four other reported children with adrenal insufficiency heralding manifestation of PAPS are discussed.

Prediction of lymph node metastases by preoperative nuclear morphometry in oral squamous cell carcinoma: a comparative image analysis study

CONTEXT

Prediction of metastases of oral squamous cell carcinoma (OSCC) using incisional biopsy.

AIMS

To assess the efficacy of nuclear morphometry in predicting the nodal metastases of OSCC and to compare manual and computer-based image analyses.

MATERIALS AND METHODS

Sixteen cases of moderately differentiated squamous cell carcinoma (8 with metastasized lymph nodes and 8 node-negative cases) were examined using manual and computer-based image analyses. Nuclear area, perimeter, circular rate, larger to shorter axis ratio, and coefficient of variance of nuclear area (NACV) were calculated from 100 nuclei of the processed incisional biopsy specimen.

STATISTICAL ANALYSIS

The parameters were compared between the node positive and negative cases using Student's t test and with the level of lymph node involved using ANOVA test and Bonferroni's post hoc assessment. Manual and computer-based image analyses were compared by Spearman's correlation.

RESULTS

A significant variation between the node positive and negative groups was observed with respect to circular rate (P = 0.031) and NACV (P = 0.036). The nuclear area (P = 0.009), perimeter (P = 0.0001), circularity (P = 0.045), and larger to shorter diameter ratio (LS ratio) (P =0.02) were significantly different in the levels of the nodes involved. There was good a correlation between manual and computer-based analyses (Spearman's rho, 0.616-0.824) in nuclear size parameters and the circular rate had a negative correlation (-0.118, P = 0.664). Nuclear circularity was better assessed by computer-based analysis.

CONCLUSION

Preoperative morphometric assessment of the nuclear features may detect early cellular changes and thus, are useful in predicting nodal metastases in OSCC.

Surface Phase Separation and Ordering in Compound Semiconductor Alloys

The orientation dependence of phase separation has been examined in detail in InGaAsP layers grown by liquid phase epitaxy on (001), (110), (111)In and (123) InP substrates. It is shown that phase separation is two-dimensional in nature and does not occur along the growth direction for the cases examined. Further, phase separation takes place along the soft directions lying in the growth plane. These results very strongly suggest that phase separation evolves at the surface while the layer is growing.

CuPt-type ordering characteristics of InGaAsP layers are presented. In addition, the Influence of growth temperature and growth rate on domain sizes have been investigated in GaInP2 layers. A model has been proposed to rationalize the formation of domains and involves steps present on the surface. Results suggest that ordering like phase separation occurs at the surface while the layers is being deposited. It is inferred that the two microstructural features evolve concomitantly at the surface during layer growth.

Large Lattice Mismatch Epitaxy

During the early stages of lattice mismatch epitaxy, island growth is observed in several systems. The evolution of this morphology is attributed to a large value of the substrate/layer interface energy. Origins of misfit and threading dislocations are also considered. Nucleation of misfit dislocations could occur either from steps present on surfaces of islands or from substrate/island edges. Arms of glide loops terminating at the surface in the first case form threading segments in the layer, whereas the coalescence of islands in which misfit dislocations are not aligned with respect to each other lead to threading dislocations in the second case. Existing approaches for lowering threading dislocation densities are also evaluated. A novel approach involving controlled, self-assembly of islands is presented to achieve the preceding objective.

Kaposi's sarcoma: a presenting manifestation of HIV infection in an Indian

Kaposi's sarcoma (KS) is a multifocal neoplastic proliferation of endothelial cells predominantly involving skin and other organs. HIV-associated Kaposi's sarcoma has been rarely reported from India. A 38-year-old male presented with persistent swelling on the left lower limb for one year along with multiple erythematous to dusky papules and plaques of one and half months duration and swelling and black discoloration of right lower limb for one month. Cutaneous examination revealed numerous skin colored and erythematous papules and plaques distributed on the left lower limb on the anteromedial aspect and verrucous plaque on the left sole. Multiple erythematous, grouped papules were present over the soft palate. Skin biopsy showed numerous slit like spaces dissecting into the collagen of the upper and mid-dermis along with 'promontory sign' suggestive of Kaposi's sarcoma. Patient was found to be HIV-positive by ELISA test.