Androgen receptor and prostate cancer

Since the original observations of Huggins and Hodges that prostate cancers are androgen dependent, androgen ablation therapy has been the gold standard for the treatment of advanced prostate cancer (CaP). Androgen receptor (AR) is believed to play critical roles in the development and progression of CaP. Treatment for neoadjuvant, adjuvant and recurrent disease all center on the regulation and manipulation of the androgen pathway, in which AR plays an integral role. Recent discoveries that frequent overexpression of ETS-related proto-oncogenes may be driven by AR as a consequence of common genomic rearrangements can hold the key towards the understanding of early phases of prostate cancer. Furthermore, AR function evolves as the cell changes towards a clinically androgen depletion independent state. Comprehension of AR function, regulation and abnormalities are increasingly refined towards the understanding of the role of AR in CaP, and in therapeutic applications. Development of future therapy for CaP will be aided by improving the knowledge of dysfunctions of AR and its network in prostate cancer. This review focuses salient features of AR and on the recent advances addressing AR dysfunctions in prostate cancer.

Growth performance and biochemical responses of three rice (Oryza sativa L.) cultivars grown in fly-ash amended soil

The disposal of fly-ash (FA) from coal-fired power stations causes significant economic and environmental problems. Use of such contaminated sites for crop production and use of contaminated water for irrigation not only decreases crop productivity but also poses health hazards to humans due to accumulation of toxic metals in edible grains. In the present investigation, three rice cultivars viz., Saryu-52, Sabha-5204, and Pant-4 were grown in garden soil (GS, control) and various amendments (10%, 25%, 50%, 75% and 100%) of FA for a period of 90 days and effect on growth and productivity of plant was evaluated vis-a-vis metal accumulation in the plants. The toxicity of FA at higher concentration (50%) was reflected by the reduction in photosynthetic pigments, protein and growth parameters viz., plant height, root biomass, number of tillers, grain and straw weight. However, at lower concentrations (10-25%), FA enhanced growth of the plants as evident by the increase of studied growth parameters. The cysteine and non-protein thiol (NP-SH) content showed increase in their levels up to 100% FA as compared to control, however, maximum content was found at 25% FA in Saryu-52 and Pant-4 and at 50% FA in Sabha-5204. Accumulation of Fe, Si, Cu, Zn, Mn, Ni, Cd and As was investigated in roots, leaves and seeds of the plants. Fe accumulation was maximum in all the parts of plant followed by Si and both showed more translocation to leaves while Mn, Zn, Cu, Ni and Cd showed lower accumulation and most of the metal was confined to roots in all the three cultivars. As was accumulated only in leaves and was not found to be in detectable levels in roots and seeds. The metal accumulation order in three rice cultivars was Fe > Si > Mn > Zn > Ni > Cu > Cd > As in all the plant parts. The results showed that rice varieties Saryu-52 and Sabha-5204 were more tolerant and could show improved growth and yield in lower FA application doses as compared to Pant-4. Thus, Sabha-5204 and Saryu-52 are found suitable for cultivation in FA amended agricultural soils for better crop yields.

Ternary biosorption studies of Cd(II), Cr(III) and Ni(II) on shelled Moringa oleifera seeds

Competitive biosorption of Cd(II), Cr(III) and Ni(II) on unmodified shelled Moringa oleifera seeds (SMOS) present in ternary mixture were compared with the single metal solution. The extent of adsorption capacity of the ternary metal ions tested on unmodified SMOS was low (10-20%) as compared to single metal ions. SMOS removed the target metal ions in the selectivity order of Cd(II) > Cr(III) > Ni(II). Sorption equilibria, calculated from adsorption data, explained favorable performance of biosorption system. Regeneration of exhausted biomass was also attempted for several cycles with a view to restore the sorbent to its original state.

Patient satisfaction following abdominoplasty: an NHS experience

Abdominoplasty is one of the few cosmetic procedures performed in the UK on the National Health Service (NHS). In the current climate of tight resource rationing many primary care trusts (PCTs) are refusing to fund such operations, resulting in a number being carried out in the independent sector. There are very few studies in the literature on patient satisfaction following abdominoplasty, with none from the UK. Our study aimed to look at the patient satisfaction rate following abdominoplasty in the NHS and study further the areas of dissatisfaction. A questionnaire survey was sent to 153 patients who underwent the procedure over a 5-year period. Replies were received from 118 (78%) patients, revealing a 77% satisfaction rate amongst responders. Further analysis of the dissatisfied patients revealed particular dissatisfaction with dog-ears, residual abdominal overhang and issues relating to the scar. The dissatisfied group was exclusively female from across the age spectrum, although analysis showed an increase in dissatisfaction with time, with the highest levels seen at 4-6 years post-abdominoplasty. This study has identified a number of areas of patient dissatisfaction, even in carefully selected patients.

Merkel cell carcinoma: a report of 34 cases and literature review

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer, with unclear histogenesis. To date there is no consensus on the optimal treatment of this neoplasm, with controversy surrounding the use of radiotherapy and chemotherapy. There are also limited data on biological behaviour and prognosis, with reported survival ranging from 31% at three years to 74% at five years.

METHOD

The medical records of 34 patients with a diagnosis of primary MCC, treated at two NHS trusts in Birmingham and Coventry, were reviewed. An extensive review of the English literature was also performed.

RESULTS

MCC occurred predominantly in Caucasians (97%) with a mean age of 75 years. Identified risk factors were a previous history of SCC (37%), BCC (18%) and AK (20%). Ten percent of patients showed evidence of immunocompromise. Most tumours were located on the extremity, where they reached a mean size of 2.1cm. Fifty percent had regional metastasis during the course of their disease. A sub group analysis of the excision margins showed that a 2-cm excision margin, extending to the deep fascia, resulted in a 50% incomplete excision rate and a 33% local recurrence rate. In contrast a 3-cm margin including deep fascia resulted in no incomplete excisions and a 10.5% local recurrence rate Prognosis was poor with a 40% 3-year survival. Combining the data from two trusts has produced a relatively large series and highlighted differences in patient characteristics and management between the units. We advocate a 3-cm excision margin, including fascia wherever possible, combined with post-operative radiotherapy to offer the best chance of local control. Survival is fairly dismal and in keeping with the aggressive nature of this tumour. The respective roles of radiotherapy and chemotherapy remain controversial.

Experience with the modified hockey stick incision for block dissection of neck

BACKGROUND

The modified hockey stick incision was originally described by Lahey in 1940. This allows elevation of a superiorly based cervical skin flap, with additional exposure of the parotid as necessary.

METHODS

The longitudinal portion of the incision runs from the mastoid process downward, behind the anterior border of the trapezius muscle, and curves gently at the junction of the lateral one-third and medial two-thirds of the clavicle. The transverse component extends medially, approximately 2 cm below the clavicle. When parotidectomy is required, incision is extended in front of the ear and a forward cut is made for additional exposure.

RESULTS

We present our experience with a series of 16 patients, undergoing a total of 17 neck dissections for various pathologies. The majority (11 patients) received postoperative radiotherapy. There were two episodes of minor skin necrosis which were not related to radiotherapy, but to patient co-morbidity, and settled with conservative management. All patients had a satisfactory cosmetic result.

CONCLUSION

We find the modified hockey stick incision to be cosmetically superior and provide excellent exposure of the neck, with protection of the carotid vessels.

Changes in amino acid profile and metal content in seeds of Cicer arietinum L. (chickpea) grown under various fly-ash amendments

Seeds of Cicer arietinum L. plants are edible and a valuable source of protein. Accumulation of toxic metals in the edible part of the plant, grown in fields close to fly-ash (FA) landfills, may pose a threat to human health. In the present study, the effects of FA and its amendments with different ameliorants viz., garden soil (GS), press mud (PM) and saw dust (SD), on total soluble protein contents, amino acid composition and metal accumulation in seeds were investigated in var. CSG-8962 and var. C-235 of C. arietinum. Plants accumulated adequate amounts of essential metals viz. Fe, Cu, Zn in seeds, while the toxic metals such as Cd and Cr were taken up in smaller quantities. The accumulation of Cr and Cd was less in var. C-235 than var. CSG-8962. Amendment of FA with PM enhanced the amount of soluble protein and amino acids in both varieties and was found to be superior among all tested ameliorants. Both quantitative and qualitative analysis of amino acids showed better response in var. C-235 as compared to var. CSG-8962. Thus var. C-235 seems to be suitable for cultivation in FA contaminated areas due to more accumulation of essential metals and less accumulation of toxic metals in seeds. Application of PM may further improve the growth of plants and nutritional quality of seeds.

Lead detoxification by coontail (Ceratophyllum demersum L.) involves induction of phytochelatins and antioxidant system in response to its accumulation

Coontail (Ceratophyllum demersum L.) plants when exposed to various concentrations of Pb (1-100microM) for 1-7days, exhibited both phytotoxic and tolerance responses. The specific responses were function of concentration and duration. Plants accumulated 1748mugPbg(-1) dw after 7d which reflected its metal accumulation ability, however most of the metal (1222microgg(-1) dw, 70%) was accumulated after 1d exposure only. The toxic effect and oxidative stress caused by Pb were evident by the reduction in biomass and photosynthetic pigments and increase in malondialddehyde (MDA) content and electrical conductivity with increase in metal concentration and exposure duration. Morphological symptoms of senescence phenomena such as chlorosis and fragmentation of leaves were observed after 7d. The metal tolerance and detoxification strategy adopted by the plant was investigated with reference to antioxidant system and synthesis of phytochelatins. Protein and antioxidant enzymes viz., superoxide dismutase (SOD, EC 1.15.1.1), guaiacol peroxidase (GPX, EC 1.11.1.7) ascorbate peroxidase (APX, EC 1.11.1.11), catalase (CAT, EC 1.11.1.6) and glutathione reductase (GR, EC 1.6.4.2) showed induction at lower concentration and duration followed by decline. All enzymes except GPX showed maximum activity after 1d. An increase in cysteine, non-protein thiols (NP-SH) and glutathione (GSH) content was observed at moderate exposure conditions followed by decline. Phytochelatins (PC(2) and PC(3)) were synthesized to significant levels at 10 and 50microM Pb with concomitant decrease in GSH levels. Thus production of PCs seems important for the detoxification of metal, however it may lead to depletion of GSH and consequently oxidative stress. Results suggest that plants responded positively to moderate Pb concentrations and accumulated high amount of metal. Due to metal accumulation coupled with detoxification potential, the plant appears to have potential for its use as phytoremediator species in aquatic environments having moderate pollution of Pb.

Characterization of the androgen receptor in a benign prostate tissue-derived human prostate epithelial cell line: RC-165N/human telomerase reverse transcriptase

The majority of prostate epithelial cell lines stably expressing wild-type (wt) or mutant (mt) androgen receptor (AR) are derived from metastatic prostate cancers. Therefore, the wt AR-expressing RC-165N/human telomerase reverse transcriptase (hTERT) cell line derived from the benign prostate tissue of an African-American patient provides a unique opportunity to assess the functional status of AR in a cellular context not studied before. Although androgen-induced expression of known androgen responsive genes such as PMEPA1, and NDRG1 was observed in RC-165N/hTERT, this cell line expresses prostate-specific antigen (PSA) at significantly lower levels. Chromatin immunoprecipitation assay revealed androgen-dependent binding of AR to androgen response elements of PSA, PMEPA1 and NDRG1 genes. Similarities, as well as differences were noted in the expression of androgen responsive genes between RC-165N/hTERT and LNCaP cells. Comprehensive evaluations of AR functions in RC-165N/hTERT cells suggest that whereas some features of known AR functions are maintained in this benign prostatic tissue-derived cell line, other AR functions are not retained. Objective evaluations of similar cell lines will lead to the understanding of AR functions in prostate growth and differentiation.

Rv3303c of Mycobacterium tuberculosis protects tubercle bacilli against oxidative stress in vivo and contributes to virulence in mice

Ability of Mycobacterium tuberculosis to survive under oxidative stress in vivo is an important aspect of pathogenesis. Rv3303c gene from M. tuberculosis encodes an NAD(P)H quinone reductase. These enzymes have been shown to manage oxidative stress in other pathogenic bacteria. We have hypothesized that Rv3303c protein will remove reactive oxygen species released by the host and hence reduce oxidative stress to M. tuberculosis. rv3303c was PCR cloned and the purified recombinant enzyme reduced superoxide generator menadione. Antisense and sense RNA constructs of rv3303c were electroporated in M. tuberculosis H37Rv. The transformants were characterized by difference in expression of specific mRNA and protein. Antisense transformants were markedly reduced in virulence as compared to sense transformants as judged by several parameters such as weight and survival of infected mice, growth in vivo, colonization and histopathology of lungs. In the presence of menadione, the sense transformant was more resistant to killing in vitro than the antisense transformant. It may be concluded that the rv3303c gene contributes to virulence of M. tuberculosis in vivo and this might be mediated in part by increased resistance to reactive oxygen intermediates thereby enhancing intracellular growth and colonization.

Urinary tract injuries at caesarean section: prevention and management

This article focuses on predisposing risk factors and mechanism of injury for urinary tract injuries at caesarean section. Tips on prevention of injury are followed by a detailed discussion of the management options when injury occurs.

Nucleotide polymorphism associated with ethambutol resistance in clinical isolates of Mycobacterium tuberculosis

Ethambutol (EMB) is a first-line drug used for antitubercular therapy in combination with other drugs as recommended by World Health Organization DOTS/DOTS-Plus regimens. EMB is also effective in the treatment of opportunistic mycobacterial infections in patients with human immunodeficiency virus. The emb locus has been considered as a drug target for EMB, and substitutions of codon 306 in Mycobacterium tuberculosis gene embB have been shown to be the most frequent and predictive mutations for EMB resistance. The aim of the present study was to detect embB and embC gene mutations in EMB-resistant clinical isolates. A total of 23 isolates of M. tuberculosis from patients with pulmonary tuberculosis were included in the study. Drug sensitivity was tested by proportion method and E-test. All 23 isolates were EMB resistant. Primers to amplify the embB and embC gene were designed, and polymerase chain reaction products were subjected for sequence analysis. H37Rv standard laboratory strain was used as control. Nucleotide sequencing showed that 16 strains had a mutation in the embB gene. The most common mutation observed in the embB gene was at codon 306, followed by mutations at codons 299 and 378 in 4 and 2 isolates, respectively. Novel mutations have been reported at codons 239, 240, 247, 282, 311, 368, 397, 446, 469, and 471. Sequence analysis of the embC gene showed mutation in 8 isolates at codon 270. Novel mutations in embC have been reported at codons 251 and 254. The most common nucleotide polymorphism in our isolates was at codons 306 and 299 in the embB gene and at codon 270 in the embC gene. A mutation at codon 306 was usually associated with high-level ethambutol resistance.

Antibiotic Susceptibility of Helicobacter pylori Clinical Isolates: Comparative Evaluation of Disk-Diffusion and E-Test Methods

Antimicrobial susceptibility of 25 Helicobacter pylori strains isolated from patients with acid peptic diseases were tested for in vitro sensitivity to commonly used antibiotics using disk-diffusion and E-test, methods. All strains tested were susceptible to tetracycline by E-test, with the minimum inhibitory concentration (MIC) values being <0.125 microg/ml for all strains except for 6 (<0.023 microg/ml). However 1 strain was resistant by disk-diffusion method. One strain was resistant to clarithromycin both by disk diffusion and E-test (MIC <48 microg/ml), and 1 strain was resistant only by disk diffusion. Only one strain was resistant to amoxicillin by disk diffusion and E-test (MIC >256 microg/ml). For ciprofloxacin, three strains were resistant by disk diffusion and two by E-test (MIC <32 microg/ml). Sixteen strains were resistant to metronidazole by disk diffusion and E-test (MIC >or= 8 microg/ml), and 1 was resistant only by E-test (MIC <48 microg/ml). Overall, 64% of the strains were resistant to metronidazole. The MIC for metronidazole was also tested by agar-dilution method, and metronidazole resistant strains had an, MIC >8 microg/ml. The disk-diffusion method showed excellent correlation with E-test results; there was 100% agreement for amoxicillin a other antibiotics showed 90% to 95% accuracy. Disk diffusion is cheaper than E-test (approximately 2.6 cents vs. 2.60 US dollars), is easy to perform, and is a reliable method for testing H. pylori susceptibility to antimicrobial agents in the clinical microbiology laboratory.

Urinary tract injuries at caesarean section: prevention and management

This article focuses on predisposing risk factors and mechanism of injury for urinary tract injuries at caesarean section. Tips on prevention of injury are followed by a detailed discussion of the management options when injury occurs.

Dimerization of human immunodeficiency virus type 1 reverse transcriptase as an antiviral target

Emergence of drug resistant strains of human immunodeficiency virus type 1 (HIV-1) is a major hindrance in the long-term treatment of HIV-1 infected individuals. Alternative strategies, including those directed to structural elements of viral targets, are needed to combat the growing acquired immune deficiency syndrome (AIDS) pandemic. The HIV-1 reverse transcriptase (RT) dimer interface, critical for dimer stability and catalytic function, is a novel target for designing new anti-HIV-1 drugs. Several existing RT inhibitors are known to impair polymerase function by destabilizing RT dimer stability and can serve as useful leads in this direction. Conversely, studies have shown that potent nonnucleoside reverse transcriptase inhibitors (NNRTIs) can enhance RT subunit interaction, which may contribute in part to the inhibitory effect of these drugs. Interface peptides are reported to suppress enzyme activity by interfering with active RT heterodimer formation. This review focuses on small molecule and peptide inhibitors that interfere with the formation of the active RT heterodimer and also discusses regions in the RT that are critical for RT dimerization that can be considered as potential targets for chemotherapeutic intervention.