Assessment of peripheral dose as a function of distance and depth from cobalt-60 beam in water phantom using TLD-100.

BACKGROUND: Innovations in cancer treatment have contributed to the improved survival rate of cancer patients. The cancer survival rates have been growing and nearly two third of those survivors have been exposed to clinical radiation during their treatment. The study of long-term radiation effects, especially secondary cancer induction, has become increasingly important. An accurate assessment of out-of-field/peripheral dose (PDs) is necessary to estimate the risk of second cancer after radiotherapy and the damage to the organs at risk surrounding the planning target volume. This study was designed to measure the PDs as a function of dose, distances, and depths from Telecobalt-60 (Co-60) beam in water phantom using thermoluminescent dosimeter-100 (TLD-100). METHODS: The PDs were measured for Co-60 beam at specified depths of 0 cm (surface), 5 cm, 10 cm, and 15 cm outside the radiation beam at distances of 5, 10, and 13 cm away from the radiation field edge using TLD-100 (G1 cards) as detectors. These calibrated cards were placed on the acrylic disc in circular tracks. The radiation dose of 2000 mGy of Co-60 beam was applied inside 10 × 10 cm2 field size at constant source to surface distance (SSD) of 80 cm. RESULTS: The results showed maximum and minimum PDs at surface and 5 cm depth respectively at all distances from the radiation field edge. Dose distributions out of the field edge with respect to distance were isotropic. The decrease in PDs at 5 cm depth was due to dominant forward scattering of Co-60 gamma rays. The increase in PDs beyond 5 cm depth was due to increase in the irradiated volume, increase in penumbra, increase in source to axis distance (SAD), and increase in field size due to inverse square factor. CONCLUSION: It is concluded that the PDs depends upon depth and distance from the radiation field edge. All the measurements show PDs in the homogenous medium (water); therefore, it estimates absorbed dose to the organ at risk (OAR) adjacent to cancer tissues/planning target volume (PTV). It is suggested that PDs can be minimized by using the SAD technique, as this technique controls sources of scattered radiation like inverse square factor and effect of penumbra up-to some extent.

Substantial P-Type Conductivity of AlN Achieved via Beryllium Doping.

Beryllium has long been predicted by first principle theory as the best p-type dopant for GaN and AlN. But experimental validation of these theories has not, until now, borne out the original predictions. A key challenge is the dopant-induced strain leading to Be rejection from substitutional sites in favor of interstitial sites, leading to self-compensation. More flexible growth methods like metal modulated epitaxy (MME) that can operate at substantially lower temperatures than traditional approaches, can more effectively place Be into the proper substitutional lattice sites. MME grown Be-doped AlN shows substantial p-type conductivity with hole concentrations in the range of 2.3 × 1015 -3.1 × 1018  cm-3  at room temperature. While others have achieved sizable carrier concentrations near surfaces via carbon doping or Si implantation, this is the only known demonstration of substantial bulk p-type doping in AlN and is a nearly 1000 times higher carrier concentration than the best previously demonstrated bulk electron concentrations in AlN. The acceptor activation energy is found to be ≈37 meV, ≈8 times lower than predicted in literature but on par with similar results for MME p-type GaN. Preliminary results suggest that the films are highly compensated. A p-AlN:Be/i-GaN:Be/n-GaN:Ge pin diode is demonstrated with substantial rectification.

Exploring threatened traditional knowledge; ethnomedicinal studies of rare endemic flora from Lesser Himalayan region of Pakistan

ABSTRACT Himalayas are one among the world biodiversity hotspots harboring many endemic medicinal plants. Despite augmentation in the documentation of ethnopharmacological knowledge of medicinal plant species, information regarding endemic species is still underway. Current paper highlights the traditional medicinal uses of rare endemic and unexplored group of plants having potential for novel chemical constituents with effective pharmacological activities. In total, 142 informants (91 male and 51 female) including seventeen traditional healers were interviewed using semi-structured questionnaire, personal observations and group discussions. Interviews were taken in field or otherwise photographs were shown for identification. Females were interviewed indirectly through male family members. For data analysis, quantitative analytical approach was adopted using ethnopharmacological indices as Relative frequency of citations and Fidelity Level. In total, 38 endemic plant species belonging to nineteen families were utilized by the local inhabitants. Highest number of endemics was belonging to Ranunculaceae (7), followed by Gentianaceae and Rosaceae (4 each) with respect to number of species. Highest number of endemics was used in fever, wound healing, throat infection and tonic (4 species each). Root was the most widely used part (36.17%) in cure of diseases and the leading mode administered was decoction (25.49%). Highest use reports and RFC values were recorded for Pimpinella stewartii (58 citations, 0.41 RFC), Caltha alba var. alba (52 citations, 0.37 RFC). Endemic plant species considerably contribute toward ethnomedicinal knowledge and despite rarity, the communities prefer their utilization. Conservation of endemics is necessary for future availability to the local communities.

The genus Coprinellus (Basidiomycota; Agaricales) in Pakistan with the description of four new species.

Mushrooms with a thin-fleshed pileus that becomes plicate on opening, deliquescent lamellae and dark brown to blackish basidiospores are commonly called coprinoid mushrooms. The genus Coprinellus is one of the important lineages of coprinoid mushroom in the family Psathyrellaceae. Species-level taxonomy in Coprinellus is based mainly on the presence or absence and the structure of veil and cystidia on the pileus, of cystidia on the lamellae and on basidiospore morphology. In this study, four new species of Coprinellus (Co.campanulatus, Co.disseminatus-similis, Co.pakistanicus and Co.tenuis) are described from Pakistan. Species descriptions are based on morphological and molecular data. Phylogenetic analyses based on nuc rDNA ITS region show that the new species Co.campanulatus and Co.disseminatus-similis are clustered in a clade including members of section Micacei; Co.tenuis falls in a clade with members of section Domestici; and Co.pakistanicus recovered in a separate clade adjacent to other recently described clades of genus Coprinellus. Morpho-anatomical descriptions of the new species and comparison with closely allied taxa are provided. With this study, the number of known species of Coprinellus in Pakistan has reached eight.

Whole-exome sequencing analysis reveals co-segregation of a COL20A1 missense mutation in a Pakistani family with striate palmoplantar keratoderma.

Palmoplantar keratoderma (PPK) is a rare group of excessive skin disorder characterized by thickness over the palms and soles. The striate palmoplantar keratoderma (PPKS) is a form in which hyperkeratotic lesions are restricted to the pressure regions extending longitudinally in the length of each finger to the palm. Dominantly inherited mutations in genes including desmoglein 1, desmoplakin and keratin 1 have been suggested as genetic causes of PPKS. In this study, we investigated a three-generation Pakistani family segregating PPKS phenotype in autosomal dominant fashion to identify genetic cause in this family. We have performed whole-exome and Sanger sequencing followed by in silico bioinformatics analysis to pinpoint candidate mutation associated with PPK. Revealed a novel heterozygous mutation (NM_020882.2, COL20A1 c. 392C > G; p.Ser131Cys) in the loop region close to fibronectin type III-1 domain of the c ollagen 20 α1. This variant was not found in our in-house 219 ethnically matched Pakistani unaffected controls and showed minor allele frequency of 3.4 × 10-5 in Exome Aggregation Consortium database containing exome data of 59,464 worldwide individuals. It was assigned as "pathogenic" by in silico prediction tools. Previously, association of mutation in the COL14A1, one of the paralogous gene of COL20A1, with PPK was reported in the study with a Chinese family. Our study proposes COL20A1 gene as another potential candidate gene for PPKS which expand the spectrum of collagen proteins in the pathogenicity of PPK.

Not All Acute Abdomen Cases in Early Pregnancy Are Ectopic; Expect the Unexpected: Renal Angiomyolipoma Causing Massive Retroperitoneal Haemorrhage.

Retroperitoneal haemorrhage (or retroperitoneal haematoma) refers to an accumulation of blood found in the retroperitoneal space. It is a rare clinical entity with variable aetiology including anticoagulation, ruptured aortic aneurysm, acute pancreatitis, malignancy, and bleeding from renal aneurysm. Diagnosis of retroperitoneal bleed is sometimes missed or delayed as presentation is often nonspecific. Multislice CT and arteriography are important for diagnosis. There is no consensus about the best management plan for patients with retroperitoneal haematoma. Stable patients can be managed with fluid resuscitation, correction of coagulopathy if any, and blood transfusion. Endovascular options involving selective intra-arterial embolisation or stent-grafts are clearly getting more and more popularity. Open repair is usually reserved for cases when there is failure of conservative or endovascular measures to control the bleeding or expertise is unavailable and in cases where the patient is unstable. Mortality of patients with retroperitoneal haematoma remains high if appropriate and timely measures are not taken. Haemorrhage from a benign renal tumour is a rarer entity which is described in this case report which emphasizes that physicians should have a wide index of suspicion when dealing with patients presenting with significant groin, flank, abdominal, or back pain, or haemodynamic instability of unclear cause. Our patient presented with features of acute abdomen and, being pregnant, was thought of having a ruptured ectopic pregnancy.

Idiopathic Pulmonary Vein Thrombus Extending into Left Atrium: A Case Report and Review of the Literature.

Pulmonary vein thrombosis (PVT) is rather an uncommon condition which presents nonspecifically and is usually associated with lung malignancy and major pulmonary surgery. Rarely could no cause be found. It causes increased pulmonary venous pressure leading to pulmonary arterial vasoconstriction and subsequent pulmonary arterial hypertension and subsequently can cause cor pulmonale if not addressed in timely fashion. Other associated complications like peripheral embolization and stroke have also been reported. This case emphasizes the importance of maintaining high index of clinical suspicion especially when CT pulmonary angiogram is negative for pulmonary embolism.

Cloning, E. coli expression, and characterization of heart lactate dehydrogenase B from river buffalo (Bubalus bubalis).

Lactate dehydrogenase is an enzyme of glycolytic pathway which catalyzes the interconversion of pyruvate and lactate. The present study describes cDNA cloning, E. coli expression and characterization of lactate dehydrogenase B (LDH-B) from the heart ventricles of river buffalo (Bubalus bubalis). Total RNA was isolated from the heart tissue, a 1005bp cDNA encoding complete polypeptide chain of 334 amino acids was generated by reverse transcriptase reaction and analyzed for nucleotide sequence. The consensus sequence obtained from both strands has shown 84% to 98% homology with that of different mammalian species. The attributed gene was cloned, expressed in BL21 (DE3) RIPL Codon Plus strain of E. coli using pET21a (+) plasmid. The purified recombinant enzyme displayed a KM value of 50 µM for pyruvate, an optimum activity at 35°C and pH 7.0. The enzyme was found as a homotetramer of 140 kDa on FPLC based gel-filtration column. Molecular weight of a subunit of enzyme as determined by mass spectrometric analysis was 36530.21 Da. The present study describes the first ever report about the cDNA sequence and characteristics of recombinant LDH-B from River buffalo.

Quantitating cell-cell interaction functions with applications to glioblastoma multiforme cancer cells.

We report on a method for quantitating the distance dependence of cell-cell interactions. We employ a microchip design that permits a multiplex, quantitative protein assay from statistical numbers of cell pairs, as a function of cell separation, with a 0.15 nL volume microchamber. We interrogate interactions between pairs of model brain cancer cells by assaying for six functional proteins associated with PI3k signaling. At short incubation times, cells do not appear to influence each other, regardless of cell separation. For 6 h incubation times, the cells exert an inhibiting influence on each other at short separations and a predominately activating influence at large separation. Protein-specific cell-cell interaction functions are extracted, and by assuming pairwise additivity of those interactions, the functions are shown to correctly predict the results from three-cell experiments carried out under the identical conditions.

Prevalence of HBV infection in suspected population of conflict-affected area of war against terrorism in North Waziristan FATA Pakistan.

BACKGROUND: Hepatitis B virus (HBV) infection is a major cause of severe liver diseases including fibrosis, hepatocellular carcinoma (HCC) and cirrhosis related end stage liver diseases (ESLD) in mankind. It is a common belief that infectious diseases have historically been responsible for the massiveness of war-related deaths, so the aim of this study was to estimate the prevalence of HBV infection and to demonstrate the various socio-economic, demographic and possible risk factors related to HBV infection among the conflict-affected peoples due to war against terrorism in North Waziristan. METHODS: Blood samples were collected from total 790 suspected individuals from the conflict-affected population of North Waziristan and were analyzed initially tested for the presence of HBsAg, HBeAg antigens, Anti-HBc and Anti-HBs antibodies using ELISA methods. All the positive samples were tested by real time PCR to confirm the presence of HBV DNA in ELISA positive specimens. RESULTS: Total of 126 (15.94%) samples were found positive for HBV DNA by real-time PCR. Among these positive subjects, 95 (75.5%) were males while 31 (24.5%) were females in a ratio of approximately 3:1. High HBV prevalence (41.26%) was observed among the subjects of subdivision Miran Shah relating to the high frequency of military activities against terrorism as compared to Mir Ali subdivision (35.7%) and Razmak subdivision (19.8%). Among the age groups, high prevalence (38.88%) was observed in age group 21-30 as compared to children and in older age groups. The modes of HBV transmission in this area was associated with re-uses of contaminated needles/syringes in medical care, barbers shops, sexual exposure and tattooing are the principal causal risks factors. Furthermore HBV infection was significantly higher in people with low socioeconomic status, in illiterate persons and in drivers. CONCLUSION: Our results indicate high prevalence rate of HBV infection in young subjects obviously confirms the entire absence of any program to fight HBV. Mass Immunization programs, awareness campaigns and education efforts should be practiced immediately to reduce HBV transmission among young peoples of this conflict zone.

Rapid, multiplexed microfluidic phage display.

The development of a method for high-throughput, automated proteomic screening could impact areas ranging from fundamental molecular interactions to the discovery of novel disease markers and therapeutic targets. Surface display techniques allow for efficient handling of large molecular libraries in small volumes. In particular, phage display has emerged as a powerful technology for selecting peptides and proteins with enhanced, target-specific binding affinities. Yet, the process becomes cumbersome and time-consuming when multiple targets are involved. Here we demonstrate for the first time a microfluidic chip capable of identifying high affinity phage-displayed peptides for multiple targets in just a single round and without the need for bacterial infection. The chip is shown to be able to yield well-established control consensus sequences while simultaneously identifying new sequences for clinically important targets. Indeed, the confined parameters of the device allow not only for highly controlled assay conditions but also introduce a significant time-reduction to the phage display process. We anticipate that this easily-fabricated, disposable device has the potential to impact areas ranging from fundamental studies of protein, peptide, and molecular interactions, to applications such as fully automated proteomic screening.

A robotics platform for automated batch fabrication of high density, microfluidics-based DNA microarrays, with applications to single cell, multiplex assays of secreted proteins.

Microfluidics flow-patterning has been utilized for the construction of chip-scale miniaturized DNA and protein barcode arrays. Such arrays have been used for specific clinical and fundamental investigations in which many proteins are assayed from single cells or other small sample sizes. However, flow-patterned arrays are hand-prepared, and so are impractical for broad applications. We describe an integrated robotics/microfluidics platform for the automated preparation of such arrays, and we apply it to the batch fabrication of up to eighteen chips of flow-patterned DNA barcodes. The resulting substrates are comparable in quality with hand-made arrays and exhibit excellent substrate-to-substrate consistency. We demonstrate the utility and reproducibility of robotics-patterned barcodes by utilizing two flow-patterned chips for highly parallel assays of a panel of secreted proteins from single macrophage cells.

A clinical microchip for evaluation of single immune cells reveals high functional heterogeneity in phenotypically similar T cells.

Cellular immunity has an inherent high level of functional heterogeneity. Capturing the full spectrum of these functions requires analysis of large numbers of effector molecules from single cells. We report a microfluidic platform designed for highly multiplexed (more than ten proteins), reliable, sample-efficient (∼1 × 10(4) cells) and quantitative measurements of secreted proteins from single cells. We validated the platform by assessment of multiple inflammatory cytokines from lipopolysaccharide (LPS)-stimulated human macrophages and comparison to standard immunotechnologies. We applied the platform toward the ex vivo quantification of T cell polyfunctional diversity via the simultaneous measurement of a dozen effector molecules secreted from tumor antigen-specific cytotoxic T lymphocytes (CTLs) that were actively responding to tumor and compared against a cohort of healthy donor controls. We observed profound, yet focused, functional heterogeneity in active tumor antigen-specific CTLs, with the major functional phenotypes quantitatively identified. The platform represents a new and informative tool for immune monitoring and clinical assessment.

Protein signaling networks from single cell fluctuations and information theory profiling.

Protein signaling networks among cells play critical roles in a host of pathophysiological processes, from inflammation to tumorigenesis. We report on an approach that integrates microfluidic cell handling, in situ protein secretion profiling, and information theory to determine an extracellular protein-signaling network and the role of perturbations. We assayed 12 proteins secreted from human macrophages that were subjected to lipopolysaccharide challenge, which emulates the macrophage-based innate immune responses against Gram-negative bacteria. We characterize the fluctuations in protein secretion of single cells, and of small cell colonies (n = 2, 3,···), as a function of colony size. Measuring the fluctuations permits a validation of the conditions required for the application of a quantitative version of the Le Chatelier's principle, as derived using information theory. This principle provides a quantitative prediction of the role of perturbations and allows a characterization of a protein-protein interaction network.