Silencing of the AV2 gene by antisense RNA protects transgenic plants against a bipartite begomovirus

Whitefly-transmitted geminiviruses (genus Begomovirus) are phytopathogens that cause heavy losses to crops worldwide. Efforts to engineer resistance against these viruses are focused mainly on silencing of complementary-sense virus genes involved in virus replication. Here we have targeted a virion-sense gene (AV2) to develop resistance against Tomato leaf curl New Delhi virus, a bipartite begomovirus prevalent throughout the Indian subcontinent. We show that tobacco plants transformed with an antisense construct targeting this gene are resistant to the virus. Following challenged with the virus, transgenic plants remained symptomless, although viral DNA could be detected in some plants by PCR. This is the first report of transgenic resistance against a bipartite begomovirus obtained by targeting a virion-sense gene. The relatively conserved nature of the gene suggests that the technology may be useful to develop broad-spectrum resistance which is required because of the fact that plants are often infected with multiple begomoviruses in the field

Hypertrophic gastric folds with hypomagnesemia, linking the dots

A Caucasian man in early 80s was seen in Gastroenterology Clinic, following, referral from the Endocrinology Clinic for concerns for CT Abdomen requested for tiredness and weight loss of three kilograms. The patient also had microcytic picture with low MCV and Ferritin and hypomagnesemia. The CT suggested gross circumferential thickening of the wall of stomach with advice for invasive investigations to further characterise the CT findings. The Endoscopy suggested grossly enlarged rugae in the stomach, and enlarged gastric polyps. Patient was assured no new sinister abnormality. Treatment challenges to consider were to stop acid suppression by prescribing Proton Pump Inhibitors (PPIs) which would lead to stomach ulcers, or to continue with PPIs with sequalae of worsening of hypertrophic gastric folds, enlarged gastric polyps and hypomagnesemia. It would be necessary to consider risk versus benefits in either situation to determine an appropriate treatment plan in the long term. With background of Zollinger-Ellison Syndrome and MEN1 with heterozygous mutation with gastrinoma of the duodenum, and frailty he was advised to continue with Proton Pump Inhibitors with twice weekly correction of Magnesium infusions, and Iron tablets following Multi-disciplinary meeting

Pepper leaf curl Lahore virus requires the DNA B component of Tomato leaf curl New Delhi virus to cause leaf curl symptoms

<p>Abstract</p> <p>Background</p> <p>Begomoviruses are whitefly-transmitted geminiviruses with genomes that consist of either two components (known as DNA A and DNA B) or a single component (homologous to the DNA A component of bipartite begomoviruses). Monopartite begomoviruses are often associated with a symptom-modulating DNA satellite (collectively known as betasatellites). Both bipartite and monopartite begomoviruses with associated satellites have previously been identified in chillies showing leaf curl symptoms in Pakistan.</p> <p>Results</p> <p><b>A </b>chilli plant (<it>Capsicum annum</it>) with chilli leaf curl disease symptoms was found to contain a begomovirus, a betasatellite and the DNA B component of <it>Tomato leaf curl New Delhi virus </it>(ToLCNDV). The begomovirus consisted of 2747 nucleotides and had the highest sequence identity (99%) <it>with Pepper leaf curl Lahore virus </it>(PepLCLV-[PK: Lah:04], acc. no. AM404179). <it>Agrobacterium</it>-mediated inoculation of the clone to <it>Nicotiana benthamiana</it>, induced very mild symptoms and low levels of viral DNA, detected in systemically infected leaves by PCR. No symptoms were induced in <it>Nicotiana tabacum </it>or chillies either in the presence or absence of a betasatellite. However, inoculation of PepLCLV with the DNA B component of ToLCNDV induced leaf curl symptoms in <it>N. benthamiana</it>, <it>N. tabacum </it>and chillies and viral DNA accumulated to higher levels in comparison to plants infected with just PepLCLV.</p> <p>Conclusions</p> <p>Based on our previous efforts aimed at understanding of diversity of begomoviruses associated with chillies, we propose that PepLCLV was recently mobilized into chillies upon its interaction with DNA B of ToLCNDV. Interestingly, the putative rep-binding iterons found on PepLCLV (GGGGAC) differ at two base positions from those of ToLCNDV (GGTGTC). This is the first experimental demonstration of the infectivity for a bipartite begomovirus causing chilli leaf curl disease in chillies from Pakistan and suggests that component capture is contributing to the emerging complexity of begomovirus diseases in the region.</p

Frequency of Intestinal Parasites in Stool Samples

Background: To study the frequency of intestinal parasites in the stool specimens Method: In this cross sectional study, 643 samples of stool were collected. Each stool sample was analyzed grossly and microscopically. Results: The highest prevalent infections were of the protozoan (84.9%). Entamoeba histolytica(63.5%), followed by Giardia lamblia(1.4% were the most prevalent. The cases of helminthiasis (Ascaris lumbricoides, Hymenolepis nana, Ankylostoma duodenale, Enterobius vermicularis and Taenia Saginata) came out to be 14.9%. Conclusion: Protozoal infections due to Entamoeba histolytica and Giardia lamblia are much more prevalent than the helminthiasis . The prevalence of intestinal parasitic infections was higher in males (62%) than females (38%)

CONCOMITANT GASTRIC AND LUNG UPTAKE OF TC-99M MDP ON BONE SCAN IN A PATIENT WITH DIFFUSE LARGE B-CELL NON-HODGKIN’S LYMPHOMA

Extra osseous uptake of Tc-99m Methylene Di Phosphonate (MDP) is not an uncommon finding on skeletal scintigraphy. However, concomitant lung and gastric uptake is a rare presentation. We presented a case report of a young male whose bone scan revealed lung and stomach uptake with a cold lesion over T7 vertebra. CT guided biopsy revealed diffuse large B-cell Non-Hodgkin’s lymphoma. Lung and gastric uptake of Tc-99m MDP on bone scan guides the reporting physician about the soft tissue calcinosis due to hypercalcemia associated with either malignant or non-malignant conditions

Myths and fallacies about epilepsy among residents of a Karachi slum area

Misconceptions about epilepsy may explain the considerable stigma accompanying it. We aimed to identify such fallacies through questionnaire-based interviews of 487 adult residents of a slum area in Karachi, Pakistan. Of those interviewed, 25% believed that epilepsy was caused by evil spirits, black magic and envy by others those without a school education were more likely to hold these views (P \u3c 0.05). Perceived complications included impotence and cancer. Shoe-sniffing was considered a treatment modality by 13%. It appears that misconceptions abound regarding epilepsy\u27s causes, complications and methods of treatment. However, those who had received a school education were less likely to link epilepsy with supernatural phenomena

Expression of a full length Arabidopsis vacuolar H+-pyrophosphatase (AVP1) gene in tobacco (Nicotiana tabbacum) to increase tolerance to drought and salt stresses

Among various abiotic stresses salinity and drought are the two major factors limiting the crop productivity. Genetically engineered salt and drought tolerant plants could provide an avenue to the reclamation of farmlands lost to agriculture because of salinity and a lack of rainfall. The Arabidopsis gene AVP1 encodes a vacuolar pyrophosphatase that functions as a proton pump and generates an electrochemical gradient in vacuole, thereby activating vacuolar membrane-antiporters including Na+/H+ antiporter, which helps in sequestration of Na+ into vacuole. In addition, over-expression of AVP1 gene increase vegetative growth by auxin transport and enhances auxin mediated root development, consequently achieving higher water absorption and retention capacities. The goal of present work is amplification of full length AVP1 (3.2kb) gene, from Arabidopsis thaliana genomic DNA through PCR, its cloning into a suitable plant expression vector and transformation in tobacco through Agrobacterium mediated transformation method for its characterization. PCR analysis showed the successful transformation of this gene in Nicotiana tabaccum. Screening of these putative transgenic plants against different salinity levels (50-250mM NaCl) showed that transgenic plants were tolerant to 250mM NaCl whereas the control plants showed wilting within 36-48 hours of salt treatment. Under periodic drought stress treatment transgenic (AVP1) plants were significantly more tolerant than wild type plants. Similarly the results of salinity and drought tolerance experiment in sand under saline and water regime conditions confirmed that introns play a key role in gene expression and regulations and improve the growth of plants. These resistant phenotypes are associated with increased internal stores of solutes

MobChain:Three-Way Collusion Resistance in Witness-Oriented Location Proof Systems Using Distributed Consensus

Smart devices have accentuated the importance of geolocation information. Geolocation identification using smart devices has paved the path for incentive-based location-based services (LBS). However, a user’s full control over a smart device can allow tampering of the location proof. Witness-oriented location proof systems (LPS) have emerged to resist the generation of false proofs and mitigate collusion attacks. However, witness-oriented LPS are still susceptible to three-way collusion attacks (involving the user, location authority, and the witness). To overcome the threat of three-way collusion in existing schemes, we introduce a decentralized consensus protocol called MobChain in this paper. In this scheme the selection of a witness and location authority is achieved through a distributed consensus of nodes in an underlying P2P network that establishes a private blockchain. The persistent provenance data over the blockchain provides strong security guarantees; as a result, the forging and manipulation of location becomes impractical. MobChain provides secure location provenance architecture, relying on decentralized decision making for the selection of participants of the protocol thereby addressing the three-way collusion problem. Our prototype implementation and comparison with the state-of-the-art solutions show that MobChain is computationally efficient and highly available while improving the security of LPS

Development of male sterility by silencing Bcp1 gene of Arabidopsis through RNA interference

The development of male sterility is one of the most important steps in hybrid seed production. Several methods for the abortion of pollens based on conventional as well as genetic engineering are reported for the various crop species. Here we have investigated the use of RNA interference (RNAi) technology to silence a male specific gene, Bcp1 in the model host Arabidopsis thaliana. Bcp1 is active in both diploid tapetum and haploid microspores. Three batches of explants (A. thaliana) were selected onherbicide glufosinate ammonium and putative transgenes were confirmed through PCR and Southern hybridization. About 49 out of 58 Arabidopsis lines transformed with RNAi construct containing Bcp1 sequences were male sterile. Transgenic plants were phenotypically indistinguishable from nontransgenic plants and by crossing with non-transgenic fertile pollens successful seed set was observed. The Bcp1 gene was also amplified from chilies, tomato and brassica. The present study resulted in developing male sterile A. thaliana (Eco. Columbia) line through genetic engineering. The diversity of Bcp1 gene will help us to produce transgenic male sterile plants in crop plants