High throughput nutritional profiling of pea seeds using Fourier transform mid-infrared spectroscopy

Seed samples from 117 genetically diverse pea breeding lines were used to determine the robustness of Fourier transform mid-infrared spectroscopy (FT-MIR) for the rapid nutritional profiling of seeds. The FT-MIR results were compared to wet chemistry methods for assessing the concentrations of total protein, starch, fiber, phytic acid, and carotenoids in pea seed samples. Of the five partial least square regression models (PLSR) developed, protein, fiber and phytic acid concentrations predicted by the models exhibited correlation coefficients greater than 0.83 when compared with data obtained using the wet chemistry methods for both the calibration and validation sets. The starch PLSR model had a correlation greater than 0.75, and carotenoids had correlation of 0.71 for the validation sets. The methods implemented in this research show the novelty and usefulness of FT-MIR as a simple, fast, and cost-effective technique to determine multiple seed constituents simultaneously.

Wheat flag leaf epicuticular wax morphology and composition in response to moderate drought stress are revealed by SEM, FTIR-ATR and synchrotron X-ray spectroscopy

Wheat (Triticum aestivum L.) is the largest cereal crop grown in Western Canada where drought during late vegetative and seed filling stages affects plant development and yield. To identify new physiochemical markers associated with drought tolerance, epidermal characteristics of the flag leaf of two wheat cultivars with contrasting drought tolerance were investigated. The drought resistant 'Stettler' had a lower drought susceptibility index, greater harvest index and water-use efficiency than the susceptible 'Superb'. Furthermore, flag leaf width, relative water content and leaf roll were significantly greater in Stettler than in Superb at moderate drought stress (MdS). Visible differences in epicuticular wax density on the adaxial flag leaf surfaces and larger bulliform cells were identified in Stettler as opposed to Superb. Mid-infrared attenuated total internal reflectance spectra revealed that Stettler flag leaves had increased asymmetric and symmetric CH₂ but reduced carbonyl esters on its adaxial leaf surface compared to Superb under MdS. X-ray fluorescence spectra revealed a significant increase in total flag leaf Zn concentrations in Stettler in response to MdS. Such information on the microstructural and chemical features of flag leaf may have potential as markers for drought tolerance and thereby accelerate the selection and release of more drought-resistant cultivars.

Morphological changes in the Heart in unrelated deaths

Background: Cardiovascular diseases are the major cause of morbidity and mortality worldwide. In the Indian subcontinent, they account for more than 25% of deaths. Numerous studies have been conducted on the cardiovascular system in cases of sudden death; but there has been a major neglect to study the heart in cases of people who died of unrelated causes.In the present study, we have attempted to study the CVS in detail in those individuals who died of unrelated causes and have tried to assess the prevelance of atherosclerosis, conduction system lesions, inflammatory and valvular pathologies in them.Materials and Methods: The present study was a prospective one conducted from June 2007 to June 2009 in the department of Pathology, Kasturba Medical College, Mangalore. The hearts of persons who died of unrelated causes were studied.Results: Various lesions encountered in the heart were coronary artery disease (70.58%), medial hyperplasia of SAnode (38.23%) and AV node (55.88%), chronic inflammation of the conduction system (55.88%) and calcification (11.76%). Malarial myocarditis was seen in 5.88% and pulmonary stenosis was seen in 2.94% of the cases. No cardiac pathology was detected in 5.88% cases.Conclusion: Our study highlights the prevelace of atherosclerotic changes and conduction system abnormalities in the general population. Hence, we conclude that examination of the CVS is extremely important in cases of sudden death; but it should also be made mandatory in unrelated deaths too, as it can diagnose a lot of hidden pathology.  

Intraosseous lipoma - A rare cause of ‘cystic’ lesion of calcaneum

Intraosseous lipoma is an uncommon benign bone neoplasm with most of them detected incidentally on multimodality imaging while being evaluated for an unrelated pathology. Long and cancellous bones are commonly involved. This lesion can present a diagnostic challenge to those uninitiated in its appearence because they can be often mistaken for other benign or malignant bone lesions such as enchondroma, fibrous dysplasia, osteoblastoma, bone infarct, bone cyst and chondrosarcoma.   Here we report a case of symptomatic calcaneal lipoma in a 50 year old lady who presented with heel pain. Plain X-ray suggested cystic lesion of calcaneum. MRI revealed the presence of intralesional fat and histopathological examination confirmed the diagnosis. We present this report for its rarity and  the clinching MRI features of this lesion, the excellent prognosis and near negligible recurrence rates, so that misdiagnosis leading to unnecessary workup, biopsy and treatment may be avoided, especially in asymptomatic patients.

Percutaneous Nephrolithotomy through an Intercostal Approach

During a 5-year period percutaneous nephrolithotripsy through an intercostal space was performed in 56 of 231 procedures. Minimal thoracic complications were seen in 3 of 53 patients with 11th intercostal space tracts into a lower, middle, or upper pole calyx. A working sheath and a pyelostomy drainage catheter were used in all these cases. Hydro- and pneumothorax requiring treatment occurred in 2 of 3 patients with a 10th intercostal space approach into an upper pole calyx combined with improper use of the working sheath and/or the pyelostomy catheter. Review of the literature also indicates that an intercostal approach appears safe when performed via the 11th intercostal space into a lower or middle pole calyx. Thoracic complications occurred when punctures were made towards an upper pole calyx or above the 11th rib. The complications may be limited by identifying the posterior inferior lung border by fluoroscopy during puncture, and performing it under general anesthesia with controlled breath-holding. The use of a working sheath to seal the pleural opening during the procedure and an efficient pyelostomy drainage catheter to allow free drainage of urine and to tamponade the tract postoperatively are also recommended.

Papillary carcinoma thyroid - A 11 year epidemiological study with histopathological correlation in a tertiary care centre in South Malabar Region in Kerala, India

Background: Thyroid cancer is the commonest endocrine malignancy. Based on recent data, thyroid cancer is the fifth most common cancer in women. To our knowledge the  present study  is the first of its kind, correlating epidemiological and histomorphological data so as to assess the  major cause hypothesis for thyroid cancers, focusing more on  papillary  carcinoma and its variants, comparing it with each other and with other  thyroid carcinomas and also correlating with gender, life style and religion.Materials and methods: This study was conducted in the Department of Pathology, MES Medical College, Perinthalmanna, Kerala, India, from January 2004 to June 2015.Two thousand and fifty thyroidectomy cases were studied.Results: Out of the total 2050  cases, thyroid cancers constituted  295 (14.39%);  of which 10.1% (208 cases) were Papillary carcinoma thyroid (PCT) and its variants; 165 cases were seen in females (79.33%) and  the incidence in males were only 20.68% (43 cases).The commonest variant encountered was classical papillary carcinoma (113 cases, 54.32%).Conclusion: Our study of papillary thyroid carcino

Cardiac conduction system- A detailed study in 46 cases of sudden death

Background: Atherosclerotic coronary artery disease is the modern pandemic and is said to be responsible for a major chunk of sudden cardiac deaths. However, in few cases; especially among the young, conduction system abnormalities were found to be the cause of death with absence of significant coronary lesions. These days, examination of the cardiac conduction system during autopsy has been abandoned as it is said to be a time consuming process. The present study was undertaken to highlight the importance of examining the cardiac conduction system in all sudden death cases.Materials and Methods: This study was a prospective one, conducted from June 2007 to June 2009 in the department of Pathology, Kasturba Medical College, Mangalore. Forty six hearts of persons who died suddenly were studied.Results: Our study showed that even though atherosclerotic coronary lesions were the most common cause of sudden death, cardiac conduction defects also contributed to a significant number of cases; especially in the young. In our study of 46 cases; 6 cases showed only conduction system abnormalities. These were young adults who had died suddenly. The predominant lesion identified in them was fibromuscular dysplasia of the nodal arteries.Conclusion: A detailed examination of the coronaries and the cardiac conduction system should be made mandatory in all sudden death cases, especially in the young as they will help to throw some light into the cause of death.Journal of Pathology of Nepal (2015) Vol. 5, 709-716

Spectrum of skin adnexal tumors with eccrineand apocrine differentiation – A single institution study of 40 cases with clinicopathological correlation

Background: Adnexal skin tumors are relatively rare and present diagnostic difficulties in view of the endless morphological spectrum, complex nomenclature and incomplete knowledge of their histogenesis. Since pathologists encounter these lesions rarely, accurate sub classification of these can be challenging. This study intends to study skin adnexal tumors with eccrine and apocrine differentiation with emphasis on their histomorphology.Materials and Methods:The present study is a five year retrospective study with comprehensive analysis of 40 cases of adnexal tumors of skin in a tertiary center in Karnataka, South India. These tumors were reclassified and subtyped according to WHO classification of skin tumors, 2006.Results and analysis:Out the 62 cases of adnexal tumors studied, 40 were tumors with eccrine and apocrine differentiation (77% benign and 23% malignant). Hidradenoma was the most common tumor comprising 37% of all tumors and 45% of the benign tumors followed byspiradenoma, cylindroma and chondroidsyringoma respectively. Head and neck region was the most common site of occurrence, and seventh decade was the most frequent age group of presentation. A definite female preponderance was noted. Pagets disease of the breast was the most common malignant tumor in this group comprising (10%). Conclusion: Histopathology is considered the gold standard in the diagnosis of these tumors and so a clear knowledge of the clinical presentation and histomorphology of these tumors is essential to make a correct diagnosis. A diagnostic logarithm based on histomorphology provides a logical approach in the subclassification of adnexal tumors.DOI:

Low grade endometrial stromal sarcoma – A series of 4 cases and review of relevant literature

Endometrial stromal tumors are rare uterine malignancies composed of cells resembling those of proliferative endometrial stroma. Because of their indistinct clinical and radiological features, these malignancies are very rarely diagnosed preoperatively. They are mostly often diagnosed as fibroid uteruspreoperatively and as a result managed conservatively many a time. Usually distinguishing these tumors from benign smooth muscle tumors of the uterus are not problematic by light microscopy, however, difficulties arise in distinction between highly cellular leiomyomas and endometrial stromal sarcomas with smooth muscle differentiation. Here we present four consecutive cases of low grade endometrial stromal sarcomaswith emphasis on their clinical, histopathological and immunohistochemical features. By this study, we have attempted to document the histologic features of LGESS with discussion of the differential diagnoses to contribute to this rare spectrum of uterine neoplasms.Journal of Pathology of Nepal (2015) Vol. 5, 774-777

Ancient orphan crop joins modern era: gene-based SNP discovery and mapping in lentil

Background

The genus Lens comprises a range of closely related species within the galegoid clade of the Papilionoideae family. The clade includes other important crops (e.g. chickpea and pea) as well as a sequenced model legume (Medicago truncatula). Lentil is a global food crop increasing in importance in the Indian sub-continent and elsewhere due to its nutritional value and quick cooking time. Despite this importance there has been a dearth of genetic and genomic resources for the crop and this has limited the application of marker-assisted selection strategies in breeding.

Results

We describe here the development of a deep and diverse transcriptome resource for lentil using next generation sequencing technology. The generation of data in multiple cultivated (L. culinaris) and wild (L. ervoides) genotypes together with the utilization of a bioinformatics workflow enabled the identification of a large collection of SNPs and the subsequent development of a genotyping platform that was used to establish the first comprehensive genetic map of the L. culinaris genome. Extensive collinearity with M. truncatula was evident on the basis of sequence homology between mapped markers and the model genome and large translocations and inversions relative to M. truncatula were identified. An estimate for the time divergence of L. culinaris from L. ervoides and of both from M. truncatula was also calculated.

Conclusions

The availability of the genomic and derived molecular marker resources presented here will help change lentil breeding strategies and lead to increased genetic gain in the future.

Glomerella truncata: another Glomerella species with an atypical mating system

In the genus Glomerella all species studied to date do not fit the usual mating system of heterothallic ascomycetes. This study investigated the mating system of G. truncata (anamorph Colletotrichum truncatum), a pathogen responsible for lentil anthracnose. Twenty-two field isolates from the Canadian prairies were crossed in all possible combinations, including selfings. All isolates also were screened for the presence of the MAT1-1 and MAT1-2 idiomorphs by targeting small conserved areas of the MAT genes (the alpha domain and the high mobility group HMG box) with degenerate primers, and a pair of G. truncata-specific HMG primers (CT21HMG) were designed. The results of the classical mating study suggested that G. truncata is heterothallic. Isolates fell into two incompatibility groups, which is consistent with a bipolar mating system but different from what has been described in other Glomerella species. Molecular screening showed that the HMG box used as a marker for the MAT1-2 idiomorph was present in both partners of fertile crosses in G. truncata, unlike in the typical ascomycete system, but as previously described for two other Glomerella species. G. truncata therefore appears to share unusual mating system characteristics with the other Glomerella species studied to date.

Capturing cold-stress-related sequence diversity from a wild relative of common bean (Phaseolus angustissimus)

One restriction to the cultivation of common bean, Phaseolus vulgaris L., is its limited tolerance to low temperatures. In the present study, subtraction suppression hybridization was employed to enrich for stress responsive genes in both a chilling-susceptible common bean and a relatively more chilling-tolerant wild bean species, Phaseolus angustissimus. For each species, approximately 11 000 expressed sequence tags were generated. Comparative sequence analysis of the EST collection with the available annotated genome sequences of the model Fabaceae species Medicago truncatula and Glycine max identified protein homologues for approximately 65% and 80% of the Phaseolus sequences, respectively. This difference reflects the closer phylogenetic relationship between the genera Phaseolus and Glycine compared with Medicago. Annotation of the Phaseolus sequences was facilitated through this comparative analysis and indicated that several heat shock proteins, cytochrome P450s, and DNA binding factors were uniquely found among the sequences from the wild species P. angustissimus. The Phaseolus sequences have been made available on a GBrowse implementation using M. truncatula as the reference genome, providing rapid access to the sequence data and associated comparative genome data.

Gangrene of the penis in a diabetic male with multiple amputations and follow up

A 60-year-old insulin dependent, diabetic male with severe atherosclerosis requiring multiple amputations in the extremities in the past, with normal renal function presented with gangrene of glans penis. He was initially treated with debridement but as the gangrene progressed, partial penile amputation was performed. He showed no further progress of the disease and had no voiding difficulties even after 4 years of follow up.

Estimation of biological half-life of tritium in coastal region of India

The present study estimates biological half-life (BHL) of tritium by analysing routine bioassay samples of radiation workers. During 2007-2009 year, 72,100 urine bioassay samples of the workers were analysed by liquid scintillation counting technique for internal dose monitoring for tritium. Two hundred and two subjects were taken for study with minimum 3 μCiL(-1) tritium uptake in their body fluid. The BHL of tritium of subjects ranges from 1 to 16 d with an average of 8.19 d. Human data indicate that the biological retention time ranges from 4 to 18 d with an average of 10 d. The seasonal variations of the BHL of tritium are 3.09 ± 1.48, 6.87 ± 0.58 and 5.73 ± 0.76 d (mean ± SD) for summer, winter and rainy seasons, respectively, for free water tritium in the coastal region of Karnataka, India, which shows that the BHL in summer is twice that of the winter season. Also three subjects showed the BHL of 101.73-121.09 d, which reveals that organically bound tritium is present with low tritium uptake also. The BHL of tritium for all age group of workers is observed independent of age and is shorter during April to May. The distribution of cumulative probability vs. BHL of tritium shows lognormal distribution with a geometric mean of 9.11 d and geometric standard deviation of 1.77 d. The study of the subjects is fit for two-compartment model and also an average BHL of tritium is found similar to earlier studies.

Hepatoprotective properties of Caesalpinia sappan Linn. heartwood on carbon tetrachloride induced toxicity

Aim of the study was to investigate the methanol and aqueous extracts of heartwood of C. sappan for its hepatoprotective activity against CCl4 induced toxicity in freshly isolated rat hepatocytes and animals. Freshly isolated rat hepatocytes were exposed to CCl4 (1%) along with/without various concentrations of methanolic and aqueous extract of C. sappan (1000-800 microg/ml) and the levels of selected liver enzymes were estimated. Antihepatotoxic effect of methanolic extract was observed in freshly isolated rat hepatocytes at concentrations 1000-800 microg/ml and was found to be similar to that of standard drug silymarin. Wistar strain albino rat model was used for the investigation of in vivo hepatoprotective properties of aqueous and methanolic extract of C. sappan (100 and 200 mg/kg body weight). Liver damage was induced by ip administration of CCl4 (30%) suspended in olive oil (1 ml/kg body weight). Both the tested extracts showed potent hepatoprotective activity at 200 mg/kg body weight test dose which was comparable with that of the standard silymarin used in similar test dose. The methanolic and aqueous extract was able to restore the biochemical levels to normal which were altered due to CCl4 intoxication in freshly isolated rat hepatocytes and also in animals.

A mutation in the LPAT1 gene suppresses the sensitivity of fab1 plants to low temperature

The Arabidopsis (Arabidopsis thaliana) fatty acid biosynthesis1 (fab1) mutant grows as well as wild type at 22 degrees C, but after transfer to 2 degrees C fab1 plants cannot maintain photosynthetic function and die after 5 to 7 weeks at 2 degrees C. A fab1 suppressor line, S7, was isolated in a screen that identified mutants that remained alive after 16 weeks at 2 degrees C and were able to flower and produce seed after return to 22 degrees C. Relative to wild type, S7 plants had reduced levels of 16:3 fatty acid in leaf galactolipids, indicating reduced synthesis of chloroplast glycerolipids by the prokaryotic pathway of lipid metabolism. The suppressor mutation was identified, by map-based and candidate-gene approaches, as a hypomorphic allele of lysophosphatidic acid acyltransferase1 (lpat1), lpat1-3. LPAT1 encodes the enzyme that catalyzes the second reaction in the prokaryotic pathway. Several lines of evidence indicate that damage and death of fab1 plants at 2 degrees C may be a result of the increased proportion of phosphatidylglycerol (PG) in fab1 that are high-melting-point molecular species (containing only 16:0, 18:0, and 16:1,Delta3-trans fatty acids). Consistent with this proposal, the lpat1-3 mutation strongly affects the fatty acid composition of PG. The proportion of high-melting-point molecular species in PG is reduced from 48.2% in fab1 to 10.7% in fab1 lpat1-3 (S7), a value close to the 7.6% found in wild type.

Genetic control and QTL analysis of cotyledon bleaching resistance in green field pea (Pisum sativum L.)

Resistance to bleaching is an important factor for quality grading of Canadian green field pea and an important selection criterion in green pea improvement. This research was conducted to determine the genetic control of bleaching resistance in green peas using 90 recombinant inbred lines (RILs) derived from a cross between cultivars Orb and CDC Striker. These lines were evaluated under field conditions for two years in two locations in Saskatchewan, Canada. Harvested whole seeds and cotyledons were evaluated for greenness using the Hunter Lab colorimeter before and after exposure to a high light intensity accelerated bleaching treatment. The RILs were genotyped using amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) molecular markers. Heritability estimates for whole seed and cotyledon greenness were moderate (0.72 and 0.69, respectively) and increased when assessed after exposing whole seeds and cotyledons to accelerated bleaching conditions (0.83 and 0.82, respectively). The genetic linkage map constructed based on a total of 224 AFLP and SSR markers spanned over 890 cM of the pea genome. Multiple QTL mapping detected major QTLs on LG IV and LG V as well as location- and year-specific QTLs on LG II and LG III associated with green cotyledon bleaching resistance in field pea. The results demonstrated the importance of the seed coat in protecting the cotyledons from bleaching.

An assessment of plankton population of Cauvery river with reference to pollution

Studies on plankton of river Cauvery water, Mettur, Salem District, Tamil Nadu was made to assess the pollution of water from January 2003 to December 2003. The qualitative and quantitative evaluation of the variation in river water showed high quantity of phytoplankton and zooplankton population throughout the study period and rotifers formed dominated group over other groups of organisms. The present study revealed that the water of river Cauvery is highly polluted by direct contamination of sewage and other industrial effluents.

A suppressor of fab1 challenges hypotheses on the role of thylakoid unsaturation in photosynthetic function

Leaf membrane lipids of the Arabidopsis (Arabidopsis thaliana) fatty acid biosynthesis 1 (fab1) mutant contain a 35% to 40% increase in the predominant saturated fatty acid 16:0, relative to wild type. This increase in membrane saturation is associated with loss of photosynthetic function and death of mutant plants at low temperatures. We have initiated a suppressor screen for mutations that allow survival of fab1 plants at 2 degrees C. Five suppressor mutants identified in this screen all rescued the collapse of photosynthetic function observed in fab1 plants. While fab1 plants died after 5 to 7 weeks at 2 degrees C, the suppressors remained viable after 16 weeks in the cold, as judged by their ability to resume growth following a return to 22 degrees C and to subsequently produce viable seed. Three of the suppressors had changes in leaf fatty acid composition when compared to fab1, indicating that one mechanism of suppression may involve compensating changes in thylakoid lipid composition. Surprisingly, the suppressor phenotype in one line, S31, was associated with a further substantial increase in lipid saturation. The overall leaf fatty acid composition of S31 plants contained 31% 16:0 compared with 23% in fab1 and 17% in wild type. Biochemical and genetic analysis showed that S31 plants contain a new allele of fatty acid desaturation 5 (fad5), fad5-2, and are therefore partially deficient in activity of the chloroplast 16:0 Delta7 desaturase. A double mutant produced by crossing fab1 to the original fad5-1 allele also remained alive at 2 degrees C, indicating that the fad5-2 mutation is the suppressor in the S31 (fab1 fad5-2) line. Based on the biophysical characteristics of saturated and unsaturated fatty acids, the increased 16:0 in fab1 fad5-2 plants would be expected to exacerbate, rather than ameliorate, low-temperature damage. We propose instead that a change in shape of the major thylakoid lipid, monogalactosyldiacylglycerol, mediated by the fad5-2 mutation, may compensate for changes in lipid structure resulting from the original fab1 mutation. Our identification of mutants that suppress the low-temperature phenotype of fab1 provides new tools to understand the relationship between thylakoid lipid structure and photosynthetic function.

Antiviral activity of medicinal plants of Nilgiris

BACKGROUND & OBJECTIVES

Medicinal plants have been traditionally used for different kinds of ailments including infectious diseases. There is an increasing need for substances with antiviral activity since the treatment of viral infections with the available antiviral drugs often leads to the problem of viral resistance. Herpes simplex virus (HSV) causes a variety of life threatening diseases. Since the chemotherapeutic agents available for HSV infections are either low in quality or limited in efficiency, there is a need to search for new and more effective antiviral agents for HSV infections. Therefore in the present study 18 plants with ethnomedical background from different families were screened for antiviral activity against HSV-1.

METHODS

Different parts of the plants collected from in and around Ootacamund, Tamil Nadu were extracted with different solvents to obtain crude extracts. These extracts were screened for their cytotoxicity against Vero cell line by assay microculture tetrazolium (MTT) trypan blue dye exclusion, proteins estimation and 3H labeling. Antiviral properties of the plant extracts were determined by cytopathic effect inhibition assay and virus yield reduction assay.

RESULTS

Three plant extracts Hypericum mysorense, Hypericum hookerianum and Usnea complanta exhibited significant antiviral activity at a concentration non toxic to the cell line used. The extracts of Melia dubia, Cryptostegia grandiflora and essential oil of Rosmarinus officinalis showed partial activity at higher concentrations.

INTERPRETATION & CONCLUSION

Some of the medicinal plants have shown antiviral activity. Further research is needed to elucidate the active constituents of these plants which may be useful in the development of new and effective antiviral agents.

Antitumor activity of total alkaloid fraction of solanum pseudocapsicum leaves

The total alkaloid fraction of the methanolic extract of Solanum pseudocapsicum leaves was tested for its in-vivo antitumor activity against Dalton's Lymphoma Ascites model in mice. The total alkaloid fraction at 2.5 and 5.0 mg/kg body weight doses exhibited antitumor activity as revealed by the significant increase in the mean survival time and the percentage increase in life span of tumor bearing mice. The antitumor activity observed may be due to its cytotoxic properties. However the treatment caused a significant decrease in the body weight below the normal indicating the toxicity of the treatment.

In vitro cytotoxicity and antitumour properties ofHypericum mysorense andHypericum patulum

The methanol extracts of the aerial parts of Hypericum mysorense and Hypericum patulum were tested for in vitro cytotoxicity on HEp-2, RD and Vero cell lines and antitumour activity using DLA and HEp-2 cell lines. The cell viability and morphological changes were assessed. Of these extracts, Hypericum patulum (stem) extract showed strong cytotoxicity against all the cell lines used. The CTC50 of the Hypericum patulum (stem) extract was 1.71 microg/mL for HEp-2, 1.53 microg/mL for RD and 2.23 microg/mL for Vero cell lines. The Hypericum patulum (leaves) and Hypericum mysorense (aerial parts) extracts showed moderate cytotoxicity and Hypericum patulum (aerial parts) extract did not show any cytotoxicity up to 1,000 microg/mL concentration. In the clonogenic assay, no colony formation was observed at a concentration of 300 micro g/mL and above for Hypericum mysorense (aerial parts), 400 microg/mL and above for Hypericum patulum (leaves) and 500 microg/mL and above for Hypericum patulum (stem) extracts. In the short term antitumour studies using DLA cells, 50% viability was observed in the concentration range 100-200 microg/mL for Hypericum patulum (leaves and stem) and 200-400 microg/mL for Hypericum mysorense (aerial) extract. In the long term antitumour activity using the HEp-2 cell line, no colony formation was observed over a concentration of 1.6 microg/mL for the Hypericum patulum (stem) extract.

Photoinhibition in mutants of Arabidopsis deficient in thylakoid unsaturation

Thylakoid lipid composition in higher plants is characterized by a high level of fatty acid unsaturation. We have screened four mutants of Arabidopsis that have reduced levels of fatty acid unsaturation. Three of the mutant lines tested, fad5, fad6, and the fad3-2 fad7-2 fad8 triple mutant, were more susceptible to photoinhibition than wild-type Arabidopsis, whereas one mutant, fab1, was indistinguishable from wild type. The fad3-2 fad7-2 fad8 triple mutant, which contains no trienoic fatty acids in its thylakoid membranes, was most susceptible to photoinhibition. Detailed investigation of photoinhibition in the triple mutant revealed that the rate of photoinactivation of PSII was the same in wild-type and mutant plants. However, the recovery of photoinactivated PSII was slower in fad3-2 fad7-2 fad8, relative to wild type, at all temperatures below 27 degrees C. These results indicate that trienoic fatty acids of thylakoid membrane lipids are required for low-temperature recovery from photoinhibition in Arabidopsis.

Discrepancies in Epstein-Barr virus association at presentation and relapse of classical Hodgkin's disease: impact on pathogenesis

BACKGROUND

Though Epstein-Barr virus (EBV) has been linked to classical Hodgkin's disease (cHD), only a proportion of cHD cases show EBV-association. While there has been evidence to suggest a crucial role for EBV in the early phase of cHD evolution, we are unclear whether continued presence of EBV is essential for the maintenance of the neoplasm. We have addressed this issue by investigating the EBV-association in paired samples of cHD obtained at presentation and relapse.

MATERIALS AND METHODS

We have analysed lymph node biopsy samples from 23 cases of cHD at presentation and relapse. In situ hybridization with EBER-1 probe and immunostaining with anti latent membrane protein-1 (LMP-1) antibody was performed on the paraffin sections. PCR for EBNA 3C gene was performed for EBV subtype analysis on the DNA extracted from paraffin sections.

RESULTS

EBV-association was documented in both the presentation and relapse samples of 14 cases. One case showed loss of EBV-association at relapse. PCR analysable DNA was obtained from both presentation and relapse samples in four of the EBV-associated cases. The EBNA 3C amplimer corresponded to type A strain of EBV in all the samples.

CONCLUSION

Loss of EBV-association between presentation and relapse seen in one case implies a hit and run mechanism in EBV-induced lymphomagenesis. Though EBV may be essential early in the evolution of cHD, it may not be required for maintenance of the neoplastic clone. Our study also brings out a speculation that a proportion of EBV-negative cHD could represent loss of EBV in the tumour prior to clinical presentation. Alternatively, an unidentified lymphotropic virus other than EBV might play a pathogenetic role in EBV-negative cHD.

Studies on the antibacterial potential of Cryptostegia grandiflora R. Br. (Asclepiadaceae) extract

Different extracts of Cryptostegia grandiflora (Roxb) Rbr. leaves were investigated for their antibacterial potential against Pseudomonus cepacia NCIM-2106, Bacillus megatorium NCIM-2087, Staphylococcus aureus NCIM-2492, Escherichia coli NCIM-2345, Bacillus subtilis NCIM-2349 and Bacillus coagulans NCIM 2323. Almost all the extracts produced significant antibacterial activity against all the microorganisms being tested and the effect so produced was comparable to the standard antibiotic, tetracycline hydrochloride. The petroleum ether (60 degrees-80 degrees C) extract showed maximum efficacy.

A role for jasmonate in pathogen defense of Arabidopsis

To investigate the role of jasmonate in the defense of plants against fungal pathogens, we have studied a mutant of Arabidopsis, fad3-2 fad7-2 fad8, that cannot accumulate jasmonate. Mutant plants were extremely susceptible to root rot caused by the fungal root pathogen Pythium mastophorum (Drechs.), even though neighboring wild-type plants were largely unaffected by this fungus. Application of exogenous methyl jasmonate substantially protected mutant plants, reducing the incidence of disease to a level close to that of wild-type controls. A similar treatment with methyl jasmonate did not protect the jasmonate-insensitive mutant coi1 from infection, showing that protective action of applied jasmonate against P. mastophorum was mediated by the induction of plant defense mechanisms rather than by a direct antifungal action. Transcripts of three jasmonate-responsive defense genes are induced by Pythium challenge in the wild-type but not in the jasmonate-deficient mutant. Pythium species are ubiquitous in soil and root habitats world-wide, but most (including P. mastophorum) are considered to be minor pathogens. Our results indicate that jasmonate is essential for plant defense against Pythium and, because of the high exposure of plant roots to Pythium inoculum in soil, may well be fundamental to survival of plants in nature. Our results further indicate that the fad3-2 fad7-2 fad8 mutant is an appropriate genetic model for studying the role of this important signaling molecule in pathogen defense.

Chloroplast development at low temperatures requires a homolog of DIM1, a yeast gene encoding the 18S rRNA dimethylase

Poikilothermic organisms require mechanisms that allow survival at chilling temperatures (2 to 15 degreesC). We have isolated chilling-sensitive mutants of Arabidopsis, a plant that is very chilling resistant, and are characterizing them to understand the genes involved in chilling resistance. The T-DNA-tagged mutant paleface1 (pfc1) grows normally at 22 degrees C but at 5 degrees C exhibits a pattern of chilling-induced chlorosis consistent with a disruption of chloroplast development. Genomic DNA flanking the T-DNA was cloned and used to isolate wild-type genomic and cDNA clones. The PFC1 transcript is present at a low level in wild-type plants and was not detected in pfc1 plants. Wild-type Arabidopsis expressing antisense constructs of PFC1 grew normally at 22 degrees C but showed chilling-induced chlorosis, confirming that the gene is essential for low-temperature development of chloroplasts. The deduced amino acid sequence of PFC1 has identity with rRNA methylases found in bacteria and yeast that modify specific adenosines of pre-rRNA transcripts. The pfc1 mutant does not have these modifications in the small subunit rRNA of the plastid.

Developmental and tissue-specific expression of a tomato anionic peroxidase (tap1) gene by a minimal promoter, with wound and pathogen induction by an additional 5'-flanking region

The tomato anionic peroxidase genes (tap1 and tap2) are induced by wounding and pathogen attack. The 5'-flanking region of tap1 confers wound- and pathogen-inducible beta-glucuronidase (GUS) expression in tobacco plants transformed with a tap1/GUS chimeric fusion gene construct. A series of nested 5' promoter deletions in the tap1/GUS fusion gene construct was created, and introduced into tobacco protoplasts via polyethylene glycol-mediated DNA transfer. A -202 construct (where the transcriptional start site is denoted +1) and larger tap1 promoter constructs showed constitutive GUS expression. A 2-fold increase in GUS expression over the high constitutive levels was observed with -358 bp and larger tap1 constructs when protoplasts were incubated with elicitor preparations from Verticillium albo-atrum. In tobacco plants transformed with the tap1 promoter deletion/GUS fusion gene constructs, wounding caused induction of GUS expression by 20 h that increased 6- to 18-fold by 72 h. The region between -202 and -358 of the tap1 promoter conferred wound responsiveness. GUS was also found to be expressed in the epidermis and trichomes in the aerial parts of transgenic plants. High-level GUS expression was observed in the nodal region of stems that was associated with the leaf traces. GUS that was absent in very young flower buds was found in the subsequent developmental stages in the pistils, ovaries and anthers. The developmentally regulated tissue-specific expression of GUS was found with all constructs containing the -202 and larger promoters whereas wound and pathogen induction required -358 or larger promoter. These results suggest that the tap1 gene, which was heretofore thought to be expressed only upon wounding or pathogen attack, plays a role in normal developmental processes of the plant and this gene acquired additional 5'-flanking promoter for the purpose of responding to wounding and fungal attack.

Inhibition of the cation-induced reversible changes in excitation energy distribution in thylakoids of BASF 13.338-grown plants

Measurements of relative quantum yields of Photosystem II and Photosystem I partial reactions and room-temperature chlorophyll a fluorescence of thylakoids in high- and low-salt media showed that the cation-induced changes in the excitation energy distribution were inhibited in the thylakoids isolated from pea plants grown in the presence of sublethal concentration of the pyridazinone herbicide BASF 13.338. Simultaneous measurement of Photosystem II and Photosystem I fluorescence emission kinetics at 77 K showed that the ability of cations to regulate excitation energy spillover from Photosystem II to Photosystem I was inhibited in thylakoids of the BASF-grown plants. Cation regulation of the absorption cross-section of the photosystems was not affected. Electron microscope data revealed that the proportion of stroma membranes relative to grana membranes was markedly less in the thylakoids of the BASF-grown plants. Furthermore, when the thylakoids were resuspended in low-salt medium, no unstacking of the grana was detected. The observed inhibition of cation-induced spillover change was presumably due to loss of ability of these photosynthetic membranes to undergo unstacking in low-salt medium.

Management of fracture of the penis in Qatar

We present 21 patients with fracture of the penis treated between July 1982 and July 1990. Eighteen patients were treated surgically, with good functional and morphological recovery; 3 refused surgery, 1 of whom had penile deformity and pain on erection. The literature is reviewed with respect to the necessity of different diagnostic and therapeutic options.

Percutaneous nephrolithotomy through an intercostal approach

During a 5-year period percutaneous nephrolithotripsy through an intercostal space was performed in 56 of 231 procedures. Minimal thoracic complications were seen in 3 of 53 patients with 11th intercostal space tracts into a lower, middle, or upper pole calyx. A working sheath and a pyelostomy drainage catheter were used in all these cases. Hydro- and pneumothorax requiring treatment occurred in 2 of 3 patients with a 10th intercostal space approach into an upper pole calyx combined with improper use of the working sheath and/or the pyelostomy catheter. Review of the literature also indicates that an intercostal approach appears safe when performed via the 11th intercostal space into a lower or middle pole calyx. Thoracic complications occurred when punctures were made towards an upper pole calyx or above the 11th rib. The complications may be limited by identifying the posterior inferior lung border by fluoroscopy during puncture, and performing it under general anesthesia with controlled breath-holding. The use of a working sheath to seal the pleural opening during the procedure and an efficient pyelostomy drainage catheter to allow free drainage of urine and to tamponade the tract postoperatively are also recommended.

Primary double pigtail stenting as a treatment of upper urinary tract leaks

During a 5-year period 21 consecutive patients with iatrogenic or traumatic upper urinary tract leaks (nonmalignant) underwent treatment 5 to 28 days later with an indwelling double pigtail stent via an antegrade or retrograde approach. Six patients underwent initial nephrostomy drainage for relief of obstruction causing decreased renal function and/or septicemia. Stent placement was successful in 20 patients and complete healing occurred within 2 to 7 weeks in all 20. At followup 2 to 32 months later (median 3 months) no stricture formation or deterioration of kidney function was noted. There were no major complications and 85% of the patients were able to leave the hospital without any form of external drainage within 1 week after stent placement.

Linitis plastica-like carcinoma of the urinary bladder

Two cases of signet-ring cell adenocarcinoma of the urinary bladder with a linitis plastica pattern of infiltration were studied. Mucin histochemistry indicated the presence of neutral and acid mucopolysaccharides and absence of sulphomucin. Immunocytochemistry of the tumour cells was positive for keratin and carcinoembryonic antigen, but negative for prostatic specific antigen and vimentin. The relevance of these observations to the differentiation and histogenesis of these tumours is discussed.

Balloon dilatation of bilharzial ureteric strictures

Balloon dilatation was performed in nine patients with bilharzial ureteric strictures. In six patients a percutaneous, antegrade approach was used and in three a balloon catheter was introduced into the ureter via a cystoscope. In another four patients, negotiation of the strictured area with a guide wire failed. In all dilated patients, symptomatic and urographic relief of the obstruction was obtained during follow-up periods of 3 to 38 months (mean 19). One patient was re-dilated after 24 months and has remained symptom-free for a further 18 months. Balloon dilatation seems to be a promising method of treating this condition.

Island patch urethroplasty: effects on urinary flow and ejaculation

Seventeen patients had a single-stage operation for urethral stricture. To avoid recurrence (which occurred in 2 patients) the urethra should be opened not only through the stricture but well beyond the pathological cavernous tissue. In 3 patients it was not possible to reconstruct the bulbocavernosus muscle over the bulb. This resulted in urethral pouching which did not interfere with micturition, except for after-dribbling, but prevented forceful ejaculation and the semen leaked slowly for several minutes. Excision of the apex of the scrotal skin flap to the island patch seems to prevent marginal skin necrosis.