Biomedical subjects

V Shanmugam

Publications and source records attributed to V Shanmugam.

At least 19 recordsLinked to original sources

PubMed2006

Diversity and differentiation among fluorescent pseudomonads in crop rhizospheres with whole-cell protein profiles.

Fluorescent pseudomonads from rhizospheres of four different crops, grown under similar soil and climatic conditions were phenotypically characterized to differentiate them into biovars. In protein electrophenogram studies of relationships among fluorescent pseudomonads by UPGMA cluster analysis based on DICE similarity index, the isolates were mainly discerned into three major clusters representing four different biovars. The biovars generally matched the delineated phenotypic clusters with the exception of a strain belonging to biovar II. However, the isolates representing similar rhizospheres and geographic locations were generally distributed into different phenotypic clusters as influenced by factors yet to be determined. The studies reinstated the importance of whole-cell protein analyses in characterizing pseudomonads and assessing their diversity.

Bacterial Proteins↗

PubMed2006

Influence of soil reaction on diversity and antifungal activity of fluorescent pseudomonads in crop rhizospheres.

The diversity and antifungal activity of fluorescent pseudomonads isolated from rhizospheres of tea, gladiolus, carnation and black gram grown in acidic soils with similar texture and climatic conditions were studied. Biochemical characterisation including antibiotic resistance assay, RAPD and PCR-RFLP studies revealed a largely homogenous population. At soil pH (5.2), the isolates exhibited growth with varying levels of siderophore production, irrespective of crop rhizospheres. Two isolates with maximum chitinase production showed antagonism. The bacterial populations in general lacked the ability to produce deleterious traits such as cellulase, pectinase and hydrogen cyanide. However, increased pH levels beyond 5.2 caused reduction in metabolite production with reduced antifungal activity. The homogeneity of the bacterial population irrespective of crop rhizospheres together with decreased secondary metabolite production at higher pH levels reinstated the importance of soil over host plant in influencing rhizosphere populations. The studies also yielded acid tolerant chitinase producing antagonistic fluorescent pseudomonads.

Biodiversity↗

PubMed2006

Extracellular chitinases of fluorescent pseudomonads antifungal to Fusarium oxysporum f. sp. dianthi causing carnation wilt.

Vascular wilt of carnation caused by Fusarium oxysporum f. sp. dianthi (Prill. & Delacr.) W. C. Synder & H.N. Hans inflicts substantial yield and quality loss to the crop. Mycolytic enzymes such as chitinases are antifungal and contribute significantly to the antagonistic activity of fluorescent pseudomonads belonging to plant-growth-promoting rhizobacteria. Fluorescent pseudomonads antagonistic to the vascular wilt pathogen were studied for their ability to grow and produce chitinases on different substrates. Bacterial cells grown on chitin-containing media showed enhanced growth and enzyme production with increased anti-fungal activity against the pathogen. Furthermore, the cell-free bacterial culture filtrate from chitin-containing media also significantly inhibited the mycelial growth. Both the strains and their cell-free culture filtrate from chitin-amended media showed the formation of lytic zones on chitin agar, indicating chitinolytic ability. Extracellular proteins of highly antagonistic bacterial strain were isolated from cell-free extracts of media amended with chitin and fungal cell wall. These cell-free conditioned media contained one to seven polypeptides. Western blot analysis revealed two isoforms of chitinase with molecular masses of 43 and 18.5 kDa. Further plate assay for mycelial growth inhibition showed the 43-kDa protein to be antifungal. The foregoing studies clearly established the significance of chitinases in the antagonism of fluorescent pseudomonads, showing avenues for possible exploitation in carnation wilt management.

Chitin↗

PubMed2005

Rubber band ligation versus excisional haemorrhoidectomy for haemorrhoids.

BACKGROUND: Traditional treatment methods for haemorrhoids fall into two broad groups: less invasive techniques including rubber band ligation (RBL), which tend to produce minimal pain, and the more radical techniques like excisional haemorrhoidectomy (EH), which are inherently more painful. For decades, innovations in the field of haemorrhoidal treatment have centred on modifying the traditional methods to achieve a minimally invasive, less painful procedure and yet with a more sustainable result. The availability of newer techniques has reopened debate on the roles of traditional treatment options for haemorrhoids. OBJECTIVES: To review the efficacy and safety of the two most popular conventional methods of haemorrhoidal treatment, rubber band ligation and excisional haemorrhoidectomy. SEARCH STRATEGY: We searched all the major electronic databases (MEDLINE, EMBASE, CENTRAL, CINAHL). SELECTION CRITERIA: Randomised controlled trials comparing rubber band ligation with excisional haemorrhoidectomy for symptomatic haemorrhoids in adult human patients were included. DATA COLLECTION AND ANALYSIS: We extracted data on to previously designed data extraction sheet. Dichtomous data were presented as relative risk and 95% confidence intervals, and continuous outcomes as weighted mean difference and 95% confidence intervals. MAIN RESULTS: Three trials (of poor methodological quality) met the inclusion criteria. Complete remission of haemorrhoidal symptom was better with EH (three studies, 202 patients, RR 1.68, 95% CI 1.00 to 2.83). There was significant heterogeneity between the studies (I2 = 90.5%; P = 0.0001). Similar analysis based on the grading of haemorrhoids revealed the superiority of EH over RBL for grade III haemorrhoids (prolapse that needs manual reduction) (two trials, 116 patients, RR 1.23, CI 1.04 to 1.45; P = 0.01). However, no significant difference was noticed in grade II haemorrhoids (prolapse that reduces spontaneously on cessation of straining) (one trial, 32 patients, RR 1.07, CI 0.94 to 1.21; P = 0.32) Fewer patients required re-treatment after EH (three trials, RR 0.20 CI 0.09 to 0.40; P < 0.00001). Patients undergoing EH were at significantly higher risk of postoperative pain (three trials, fixed effect; 212 patients, RR 1.94, 95% CI 1.62 to 2.33, P < 0.00001). The overall delayed complication rate showed significant difference (P = 0.03) (three trials, 204 patients, RR 6.32, CI 1.15 to 34.89) between the two interventions. AUTHORS' CONCLUSIONS: The present systematic review confirms the long-term efficacy of EH, at least for grade III haemorrhoids, compared to the less invasive technique of RBL but at the expense of increased pain, higher complications and more time off work. However, despite these disadvantages of EH, patient satisfaction and patient's acceptance of the treatment modalities seems to be similar following both the techniques implying patient's preference for complete long-term cure of symptoms and possibly less concern for minor complications. So, RBL can be adopted as the choice of treatment for grade II haemorrhoids with similar results but with out the side effects of EH while reserving EH for grade III haemorrhoids or recurrence after RBL. More robust study is required to make definitive conclusions.

Hemorrhoids↗

PubMed2005

Systematic review of randomized trials comparing rubber band ligation with excisional haemorrhoidectomy.

BACKGROUND AND METHOD: This review compares the two most popular treatments for haemorrhoids, namely rubber band ligation (RBL) and excisional haemorrhoidectomy. Randomized trials were identified from the major electronic databases. Symptom control, retreatment, postoperative pain, complications, time off work and patient satisfaction were assessed. Relative risk (RR) and weighted mean difference with 95 per cent confidence interval (c.i.) were estimated using a random-effects model for dichotomous and continuous outcomes respectively. RESULTS: Three trials met the inclusion criteria and all were of poor methodological quality. Complete remission of haemorrhoidal symptoms was better after haemorrhoidectomy (RR 1.68 (95 per cent c.i 1.00 to 2.83)). There was significant heterogeneity between the studies (I(2) = 90.5 per cent; P < 0.001). Fewer patients required retreatment after haemorrhoidectomy (RR 0.20 (95 per cent c.i 0.09 to 0.40)), but anal stenosis, postoperative haemorrhage and incontinence to flatus were more common with this operation. CONCLUSIONS: Haemorrhoidectomy produced better long-term symptom control in patients with grade III haemorrhoids, but was associated with more postoperative complications than RBL.

Hemorrhoids↗

PubMed2005

Role of extracytoplasmic leucine rich repeat proteins in plant defence mechanisms.

Plant-pathogen interactions involve highly complex series of reactions in disease development. Plants are endowed with both, resistance and defence genes. The activation of defence genes after contact with avirulence gene products of pathogens depends on signals transduced by leucine-rich repeats (LRRs) contained in resistance genes. Additionally, LRRs play roles for various actions following ligand recognition. Polygalacturonase inhibiting proteins (PGIPs), the only plant LRR protein with known ligands, are pectinase inhibitors, bound by ionic interactions to the extracellular matrix (ECM) of plant cells. They have a high affinity for fungal endopolygalacturonases (endoPGs). PGIP genes are organised in families encoding proteins with similar physical characteristics but different specificities. They are induced by infection and stress related signals. The molecular basis of PG-PGIP interaction serves as a model to understand the evolution of plant LRR proteins in recognising non-self-molecules. Extensins form a different class of structural proteins with repetitive sequences. They are also regulated by wounding and pathogen infection. Linkage of extensins with LRR motifs is highly significant in defending host tissues against pathogen invasion. Overexpression of PGIPs or expression of several PGIPs in a plant tissue, and perhaps manipulation of extensin expression could be possible strategies for disease management.

Extracellular Matrix↗

PubMed2005

Outcomes after placement of colorectal stents.

BACKGROUND: Colonic stents are increasingly used to palliate or alleviate large bowel obstruction in patients with colon cancer and other obstructing lesions in whom a definitive surgical procedure is inappropriate. We report on the outcomes of a large group of patients who underwent deployment of a colon stent in a single institution by a single operator. PATIENTS AND METHODS: This was a retrospective observational cohort study of all patients undergoing colonic stenting between September 1995 and May 2002. Data collected included nature of pathology, type of stent used, procedure morbidity, patient survival and details of any definitive procedures performed after stenting. RESULTS: One hundred and seven patients were evaluated (58 male) with a median age of 75 years (range 36-99 years). A total of 112 stents were successfully deployed (46 as an emergency). Twelve patients had double stents inserted coaxially and overlapping. In 7 patients the stent could not be safely deployed. Eighty-seven patients had colorectal cancer, 13 patients had an extra-luminal malignancy, 5 had diverticular strictures and in 2 patients the pathology was unknown. At last review (May 2002) 18 patients were alive, 82 patients had died and 7 patients had been lost to follow-up. Of those patients who died, the median survival after stenting alone was 6 weeks (range 4 days-36 weeks). Ten patients underwent subsequent definitive surgery. Stent complications included, 2 colonic perforations, 3 stent occlusions and 4 stent migrations. CONCLUSION: Colonic stenting can be used effectively, with acceptable morbidity, to manage patients presenting with large bowel obstruction. In a smaller number of patients colon stents may safely temporize symptoms while definitive surgery is planned.

Adult↗

PubMed2005

Pathological audit of stapled haemorhoidopexy.

INTRODUCTION: Stapled haemorrhoidopexy is increasingly used for the surgical management of prolapsing haemorrhoids. Accurate placement of the staple line is essential to avoid involvement of the internal anal sphincter (IAS) and the pain sensitive squamous epithelium. The aim of this study was to correlate histology with symptomatic outcome after stapled haemorrhoidopexy. PATIENTS AND METHODS: A single pathologist reviewed one hundred and six consecutive rectal mucosal specimens. Each specimen was assessed for the presence of columnar, transitional and squamous epithelium as well as involvement of smooth and skeletal muscle. In November 2003 all patients were sent a previously validated postal questionnaire about haemorrhoidal symptoms and a Cleveland Clinic continence scale. Symptomatic outcome was compared between patients who did or did not have squamous epithelium involvement in their pathology specimens and were analysed by Mann-Whitney U-test. RESULTS: One hundred and six stapled haemorrhoidopexies were performed between June 2001 and September 2003. Eighty-four patients (79%) returned the questionnaire; 19 patients had squamous epithelium present in the pathology specimens. There was no significant difference between symptom or Cleveland Clinic scores in patients with or without squamous epithelium in their pathology specimens. Some specimens (n = 6) were found to have smooth muscle underlying squamous epithelium; this was interpreted as the presence of internal anal sphincter (IAS) within the specimen. There was no significant difference in Cleveland Clinic scores between this group and those without IAS involvement. CONCLUSION: This study has not demonstrated a long-term difference in symptomatic outcome or continence in patients who have squamous epithelium present in their stapled haemorrhoidopexy specimens.

Adult↗

PubMed2005

Is magnetic resonance cholangiopancreatography the new gold standard in biliary imaging?

The timing and technique of perioperative biliary imaging in relation to laparoscopic surgery remains controversial. This study assessed the predictive value of magnetic resonance cholangiopancreatography (MRCP) in the diagnosis of biliary pathology. Clinical, laboratory and investigational data were evaluated from 374 patients undergoing MRCP at two hospital sites over a 5-year period. MRCP findings were compared with endoscopic retrograde cholangiopancreatography (ERCP) or operative findings and appropriate clinical endpoints. Complete data were available for 351 of the 374 patients (94%), of whom 232 (66%) were female. Median age was 64 years. The predominant presentation was abdominal pain (n = 190). Features of pancreatitis were present in 59, cholangitis in 26 and jaundice in 109 patients. Ultrasound was the initial investigation in 312 (89%) (176-gallstone positive). Common duct dilatation was evident in 114 patients and ductal calculi in 31. ERCP was successful in 212/283 (75%) patients. Significant ERCP induced pancreatitis occurred in 12 (5.6%). Comparison between MRCP and ERCP was not possible in 85 due to failure of either technique. Nine patients underwent other investigations including intraoperative cholangiogram (IOC), percutaneous transhepatic cholangiogram (PTC) and were included. Of the 221 patients with full comparative data available the MRCP showed a sensitivity of 97.98% and specificity of 84.4%. MRCP is highly sensitive and specific for choledocholithiasis and avoids the need for invasive imaging in most patients with suspected choledocholithiasis.

Abdominal Pain↗

PubMed2003

A novel, divergent simian T-cell lymphotropic virus type 3 in a wild-caught red-capped mangabey (Cercocebus torquatus torquatus) from Nigeria.

We present here a novel, distinct simian T-cell lymphotropic virus (STLV) found in a red-capped mangabey (Cercocebus torquatus) (CTO-NG409), wild-caught in Nigeria, that showed an HTLV-2-like Western blot (WB) seroreactivity. The complete genome (8920 bp) of CTO-NG409 STLV was related to but different from STLV-3/PHA-PH969 (13.5 %) and STLV-3/PPA-F3 (7.6 %), and STLV-3/CTO604 (11.3 %), found in Eritrean and Senegalese baboons, and red-capped mangabeys from Cameroon, respectively. Phylogenetic analysis of a conserved tax (180 bp) sequence and the env gene (1482 bp) confirmed the relatedness of STLV-3/CTO-NG409 to the STLV-3 subgroup. Molecular clock analysis of env estimated that STLV-3/CTO-NG409 diverged from East and West/Central African STLV-3s about 140,900+/-12,400 years ago, suggesting an ancient African origin of STLV-3. Since phylogenetic evidence suggests multiple interspecies transmissions of STLV-1 to humans, and given the antiquity and wide distribution of STLV-3 in Africa, a search for STLV-3 in human African populations with HTLV-2-like WB patterns is warranted.

Animals↗

PubMed2002

Immunology of the pathogen virulence and phytotoxin production in relation to disease severity: a case study in sheath blight of rice.

Polyclonal antibodies against purified Rhizoctonia solani toxin obtained from infected rice sheath tissues (sheath blight toxin, SBT) and culture filtrates (culture filtrate toxin, CFT) were developed in rabbit and chicken. The IgG was isolated from serum and egg yolk of rabbit and chicken, respectively, and their specificity was investigated by indirect ELISA. Antibodies developed against CFT and SBT in rabbits exhibited relatively higher titer values when compared to chicken antibodies. Positive correlation was observed between the degree of sheath blighting and the levels of antigens induced by each isolate during sheath blight symptom development as detected by rabbit SBT antibody and the isolate RS7 was identified as most virulent. Optimization of incubation period for maximum toxin production in liquid medium and rice sheaths indicated that the production of CFT and SBT is maximum after 15 d and 6 d of pathogen inoculation. Studies of the possible translocation of RS-toxin in rice plants upon inoculation with R. solani showed downward translocation as detected by rabbit/chicken SBT antibodies. Since plant inoculation required a higher concentration of inoculum and maintenance of plants, serological assay by ELISA is more sensitive than whole-plant assays in detecting RS-toxin, with the advantage that ELISA also allows rapid determination of RS-toxin production.

Animals↗

PubMed2001

Lack of cross-species transmission of porcine endogenous retrovirus infection to nonhuman primate recipients of porcine cells, tissues, or organs.

BACKGROUND: Nonhuman primates (NHPs) have been widely used in different porcine xenograft procedures inevitably resulting in exposure to porcine endogenous retrovirus (PERV). Surveillance for PERV infection in these NHPs may provide information on the risks of cross-species transmission of PERV, particularly for recipients of vascularized organ xenografts for whom data from human clinical trials is unavailable. METHODS: We tested 21 Old World and 2 New World primates exposed to a variety of porcine xenografts for evidence of PERV infection. These NHPs included six baboon recipients of pig hearts, six bonnet macaque recipients of transgenic pig skin grafts, and nine rhesus macaque and two capuchin recipients of encapsulated pig islet cells. Serologic screening for PERV antibody was done by a validated Western blot assay, and molecular detection of PERV sequences in peripheral blood mononuclear cells (PBMCs) and plasma was performed using sensitive polymerase chain reaction and reverse transcriptase-polymerase chain reaction assays, respectively. Spleen and lymph node tissues available from six bonnet macaques and three rhesus macaques were also tested for PERV sequences. RESULTS: All plasma samples were negative for PERV RNA suggesting the absence of viremia in these xenografted animals. Similarly, PERV sequences were not detectable in any PBMC and tissue samples, arguing for the lack of latent infection of these compartments. In addition, all plasma samples were negative for PERV antibodies. CONCLUSION: These data suggest the absence of PERV infection in all 23 NHPs despite exposure to vascularized porcine organs or tissue xenografts and the use of immunosuppressive therapies in some animals. These findings suggest that PERV is not easily transmitted to these NHP species through these types of xenografts.

Animals↗

PubMed2001

Evidence of porcine endogenous retroviruses in porcine factor VIII and evaluation of transmission to recipients with hemophilia.

Since 1984, unheated porcine clotting factor VIII (Hyate:C) has been used to treat severe bleeding episodes in persons with hemophilia who have antibodies to human clotting factor. We document the presence of porcine endogenous retrovirus (PERV) in plasma samples of pigs and in clinical lots of Hyate:C. Both gag and pol PERV RNA sequences were detected by reverse-transcriptase (RT) polymerase chain reaction in 13 of 13 lots of Hyate:C tested. Among 10 of these lots, RT activity also was detected, which confirms the presence of retroviral particles. To assess the transmission of PERV to Hyate:C recipients, we tested serum specimens from 88 recipients of Hyate:C and 23 noninfused control subjects for anti-PERV antibodies by using a Western blot assay. None of the samples was positive. Our data document that PERV particles are a common contaminant of Hyate:C products and suggest that the risk of PERV transmission from these percutaneous exposures is very low.

Animals↗

PubMed2001

Purification and characterization of an extracellular alpha-glucosidase protein from Trichoderma viride which degrades a phytotoxin associated with sheath blight disease in rice.

AIMS: To purify and characterize an extracellular alpha-glucosidase from Trichoderma viride capable of inactivating a host-specific phytotoxin, designated RS toxin, produced by the rice sheath blight pathogen, Rhizoctonia solani Kühn. METHODS AND RESULTS: The host-specific RS toxin was purified from both culture filtrates (culture filtrate toxin, CFTox) and R. solani-inoculated rice sheaths (sheath blight toxin, SBTox). Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analyses of extracellular proteins, purified from a biocontrol fungus T. viride (TvMNT7) grown on SBTox and CFTox separately, were carried out. The antifungal activity of the purified high molecular weight protein (110 kDa) was studied against RS toxin as well as on the sclerotial germination and mycelial growth of R. solani. Enzyme assay and Western blot analysis with the antirabbit TvMNT7 110-kDa protein indicated that the protein was an alpha-glucosidase. The 110-kDa protein was highly specific to RS toxin and its Michaelis-Menten constant value was 0.40 mmol l-1 when p-nitrophenyl alpha-D-glucopyranoside was used as the substrate. The isoelectric point of the protein was 5.2. N-terminal sequencing of the alpha-glucosidase protein showed that its amino acid sequence showed no homology with other known alpha-glucosidases. CONCLUSION: This appears to be the first report of the purification and characterization of an alpha-glucosidase capable of inactivating a host-specific toxin of fungal origin. The alpha-glucosidase is specific to RS toxin and is different from the known alpha-glucosidases. SIGNIFICANCE AND IMPACT OF THE STUDY: As RS toxin could be inactivated by the microbial alpha-glucosidase enzyme, isolation of the gene that codes for the enzyme from T. viride and transfer of the gene to rice plants would lead to enhanced resistance against sheath blight pathogen by inactivation of RS toxin.

Amino Acid Sequence↗

PubMed2001

Evidence of infection with simian type D retrovirus in persons occupationally exposed to nonhuman primates.

Simian type D retrovirus (SRV) is enzootic in many populations of Asian monkeys of the genus Macaca and is associated with immunodeficiency diseases. However, the zoonotic potential of this agent has not been well defined. Screening for antibodies to SRV was performed as part of an ongoing study looking for evidence of infection with simian retroviruses among persons occupationally exposed to nonhuman primates (NHPs). Of 231 persons tested, 2 (0.9%) were found to be strongly seropositive, showing reactivity against multiple SRV antigens representing gag, pol, and env gene products by Western immunoblotting. Persistent long-standing seropositivity, as well as neutralizing antibody specific to SRV type 2, was documented in one individual (subject 1), while waning antibody with eventual seroreversion was observed in a second (subject 2). Repeated attempts to detect SRV by isolation in tissue culture and by using sensitive PCR assays for amplification of two SRV gene regions (gag and pol) were negative. Both individuals remain apparently healthy. We were also unable to transmit this seropositivity to an SRV-negative macaque by using inoculation of whole blood from subject 1. The results of this study provide evidence that occupational exposure to NHPs may increase the risk of infection with SRV and underscore the importance of both occupational safety practices and efforts to eliminate this virus from established macaque colonies.

Animals↗

PubMed2000

Induction of long-term protective effects against heterologous challenge in SIVhu-infected macaques.

A group of three rhesus macaques were inoculated with SIV isolated from a human (SIVhu) accidentally exposed and infected with SIVsm. Extensive sequence analyses of SIVhu obtained from the human and macaques following infection indicated the presence of truncated nef. Not only did nef fail to repair itself in vivo postinfection (p.i.), but instead, further mutations added additional stop codons with increasing time p.i. Infection of these animals was associated with minimal acute viral replication, followed by undetectable plasma viral loads and only intermittent PCR detection up to 5 years p.i. The three SIVhu infected and three control monkeys were then challenged with the heterologous highly pathogenic SHIV89.6p. All three controls became infected and showed rapid declines in peripheral CD4(+) lymphocytes, disease, and death at 10 and 32 weeks p.i., respectively. In contrast, all three animals previously infected with SIVhu are healthy and exhibit stable CD4(+) lymphocyte levels and undetectable plasma viral loads at >20 months post-SHIV89. 6p challenge. Only transient, low levels of SHIV replication were noted in these animals. Whereas responses to SIVgag/pol were noted, no evidence for SIV/SHIV envelope cross-reactivity was detected by antibody or CTL analyses, suggesting that the protective immune mechanisms to the heterologous challenge isolate were most likely not directed to envelope but rather to other viral determinants.

Animals↗

PubMed2000

Lower HIV-2 plasma viral loads may explain differences between the natural histories of HIV-1 and HIV-2 infections.

To explain the low transmissibility and pathogenicity of HIV-2 infection's plasma viral loads in both HIV-1- and HIV-2-infected persons were compared by using the polymerase chain reaction (PCR)-based Amp-RT assay to measure levels of reverse transcriptase (RT) activity. The study comprised a total of 155 HIV-infected-people including 58 who were infected with HIV-2 with CD4+ cell counts <500 x 106/L (n = 15), CD4+ cell counts >500 x 106/L (n = 26), or with tuberculosis (TB; n = 17), and 97 HIV-1-infected people with CD4+ cell counts <500 x 106/L (n = 32), CD4+ cell counts >500 x 106/L (n = 25), or TB (n = 40). Among persons with CD4+ cell counts <500 x 106/L, 11 (73.3%) of 15 HIV-2-infected persons had detectable plasma RT activity compared with 25 (78.1%) of 32 HIV-1-infected persons (p =.725). However, the median HIV-2 plasma RT activity in this group was significantly lower (2561 x 10-10 U/ml; p =.036; detectable range, 1712-644,868 x 10-10 U/ml) than the RT activity of HIV-1-infected persons with similar CD4+ cell counts (13,241 x 10-10 U/ml; detectable range, 8482-1,478,880 x 10-10 U/ml). Among TB patients, 10 (58.8%) of 17 HIV-2-infected persons had detectable plasma RT activity compared with 30 (75%) of 40 HIV-1-infected persons (p =.342). In contrast, among patients with CD4+ cell counts >500 x 106/L, none of 26 HIV-2-infected persons had detectable RT activity compared with 13 (52%) of 25 HIV-1-infected persons (p <.001). Our data suggest that unlike HIV-1 infection, HIV-2 infections with CD4+ cell counts >500 x 106/L are associated with a low level of viral replication, which may explain the longer clinical latency and lower transmissibility seen in HIV-2 infection.

CD4 Lymphocyte Count↗

PubMed2000

Inactivation of phytotoxin produced by the rice sheath blight pathogen Rhizoctonia solani.

The rice sheath blight pathogen, Rhizoctonia solani, produces a toxin designated as RS-toxin, a carbohydrate compound containing mainly alpha-glucose and mannose. Different microflora were tested for RS-toxin inactivation. Isolates of Trichoderma viride inactivated this toxin when it was provided as the sole food source, and these isolates reduced the severity of toxin-induced symptoms and electrolyte leakage from rice cells. The best-performing isolate, TvMNT7, produced two extracellular proteins of 110 and 17 kDa. The high molecular mass protein was shown to have alpha-glucosidase activity. The purified 110 kDa protein was able to reduce RS-toxin activity.

Blotting, Western↗