1.Extra-anatomical veno-venous surgical bypass for central vein occlusion in patients with ipsilateral arterio-venous fistula (AVF) for haemodialysis - A single centre experience
Saravana Kumar Selvanathan ; Zainal Ariffin Azizi
The Medical Journal of Malaysia 2017;72(1):3-6
Objective: Central vein occlusion is a common complication
related to central vein catheter insertion for haemodialysis
which can be unmasked by an ipsilateral fistula creation,
leading to a dysfunctional arteriovenous fistula (AVF). We
describe an extra-anatomical venous bypass surgical
procedure performed to maintain vascular access and
reduce the symptoms of swelling of the ipsilateral upper
limb, neck and face.
Materials and Methods: We report 20 consecutive patients
with end-stage renal failure (ESRF) who had central vein
occlusion and were not amenable to endovascular
intervention. They underwent extra-anatomical vein to vein
surgical bypass. The axillary and iliac or femoral veins were
approached via infraclavicular and extraperitoneal groin
incisions respectively. In all the patients, an externally
supported 6 or 8 mm polytetrafluoroethylene (PTFE) graft
was used as a conduit and was tunnelled extra-anatomical.
All patients had double antiplatelet (Aspirin and Clopidogrel)
therapy post-operatively.
Results: Substantial improvement in the facial, neck and
upper limb swelling was noticed following this diversion
surgery. The vein to vein bypass was patent at 12 months in
10 out of 20 patients. Graft infection occurred in two (10%)
cases. Re-thrombectomy or assisted patency procedure
(stent/plasty) was done in four (20%) cases. The patients
with preoperative fistula flow rate of more than 1500 ml/min
and post-operative graft flow rate of more than a 1000 ml/min
were patent at 12 months (P=0.025 and p=0.034
respectively).
Conclusion. Axillary to iliac/femoral vein bypass can salvage
functioning ipsilateral fistula threatened by occluded upper
central vein and relieve their upper limb obstructive venous
symptoms.
2.Evaluation of antiviral and cytotoxic activities of methanolic extract of S. grandiflora (Fabaceae) flowers
Arthanari Kumar Saravana ; Vanitha Jayachandran ; Ganesh Mani ; Venkateshwaran Krishnasamy ; Clercq De
Asian Pacific Journal of Tropical Biomedicine 2012;(z2):855-858
Objective: To investigate the cytotoxicity and antiviral activity of methanolic extract of S.grandiflora flowers using different cell lines and viruses. Methods: The methanolic flower extracts were prepared and evaluated for their antiviral and cytotoxic activities using viruses like herpes simplex-1 and 2, vaccinia, vesicular stomatitis, cox sackie, respiratory syncytical, feline corona, feline herpes, para influenza, reo-1, sindbis and punta toro viruses in different cell lines, like Hel, HeLa, Crandell Reus feline kidney and Vero cell cultures. Results: Among the viruses used the extract possessed strongest antiviral activity against herpes simplex 1 and 2, repiratory syncytical, para influenza, reo, sindbis, cox sackie and punta toro viruses that was (EC50=20 μg/mL and 45 μg/mL) and moderate activity for remaining viruses (EC50= 100 μg/mL). The antiviral activities assessed by calculating the selectivity index may be due to the presence of flavonoids in the extracts there by inhibit the virus cell fusion in the early and replication stages. The cytotoxicity effect was evaluated using MTT assay and the results revealed that the extracts exhibited cytotoxicity from the range of 20 to 100 μg/mL. Conclusions: Present results confirmed that the S. grandiflora used as a good antimicrobial agent in future.
3.Comparative Analysis of Effect of Density, Insertion Angle and Reinsertion on Pull-Out Strength of Single and Two Pedicle Screw Constructs Using Synthetic Bone Model.
Venkatesh KRISHNAN ; Vicky VARGHESE ; Gurunathan Saravana KUMAR
Asian Spine Journal 2016;10(3):414-421
STUDY DESIGN: Biomechanical study. PURPOSE: To determine the effect of density, insertion angle and reinsertion on pull-out strength of pedicle screw in single and two screw-rod configurations. OVERVIEW OF LITERATURE: Pedicle screw pull-out studies have involved single screw construct, whereas two screws and rod constructs are always used in spine fusions. Extrapolation of results using the single screw construct may lead to using expensive implants or increasing the fusion levels specifically in osteoporotic bones. METHODS: Single screw and two screw pull-out strength tests were carried out according to American Society for Testing and Materials F 543-07 on foam models to test the effect of density, insertion angle and reinsertion using poly axial pedicle screws. RESULTS: Bone density was the most significant factor deciding the pull-out strength in both single and two screw constructs. The difference in pull-out strength between single screw and two screw configurations in extremely osteoporotic bone model (80 kg/m3) was 78%, whereas in the normal bone model it was 48%. Axial pull-out value was highest for the single screw configuration; in the two screw configuration the highest pull-out strength was at 10°-15°. There was an 18% reduction in pull-out strength due to reinsertion in single screw configuration. The reinsertion effect was insignificant in the two screw configuration. CONCLUSIONS: A significant difference in response of various factors on holding power of pedicle screw between single and two-screw configurations is evident. The percentage increase in pull-out strength between single and two screw constructs is higher for osteoporotic bone when compared to normal bone. Reinsertion has no significant effect on pull-out strength in the two screw rod configuration.
Bone Density
;
Osteoporosis
;
Pedicle Screws*
;
Spine
4.Comparative Analysis of Effect of Density, Insertion Angle and Reinsertion on Pull-Out Strength of Single and Two Pedicle Screw Constructs Using Synthetic Bone Model.
Venkatesh KRISHNAN ; Vicky VARGHESE ; Gurunathan Saravana KUMAR
Asian Spine Journal 2016;10(3):414-421
STUDY DESIGN: Biomechanical study. PURPOSE: To determine the effect of density, insertion angle and reinsertion on pull-out strength of pedicle screw in single and two screw-rod configurations. OVERVIEW OF LITERATURE: Pedicle screw pull-out studies have involved single screw construct, whereas two screws and rod constructs are always used in spine fusions. Extrapolation of results using the single screw construct may lead to using expensive implants or increasing the fusion levels specifically in osteoporotic bones. METHODS: Single screw and two screw pull-out strength tests were carried out according to American Society for Testing and Materials F 543-07 on foam models to test the effect of density, insertion angle and reinsertion using poly axial pedicle screws. RESULTS: Bone density was the most significant factor deciding the pull-out strength in both single and two screw constructs. The difference in pull-out strength between single screw and two screw configurations in extremely osteoporotic bone model (80 kg/m3) was 78%, whereas in the normal bone model it was 48%. Axial pull-out value was highest for the single screw configuration; in the two screw configuration the highest pull-out strength was at 10°-15°. There was an 18% reduction in pull-out strength due to reinsertion in single screw configuration. The reinsertion effect was insignificant in the two screw configuration. CONCLUSIONS: A significant difference in response of various factors on holding power of pedicle screw between single and two-screw configurations is evident. The percentage increase in pull-out strength between single and two screw constructs is higher for osteoporotic bone when compared to normal bone. Reinsertion has no significant effect on pull-out strength in the two screw rod configuration.
Bone Density
;
Osteoporosis
;
Pedicle Screws*
;
Spine
5.Identification of Pedicle Screw Pullout Load Paths for Osteoporotic Vertebrae
Venkatesh KRISHNAN ; Vicky VARGHESE ; Gurunathan Saravana KUMAR ; Narayan YOGANANDAN
Asian Spine Journal 2020;14(3):273-279
Results:
Pullout strength decreased by 36% when the size of the revision screw was increased by 1 mm, while it increased by 35% when the size of the revision screw was increased by 2 mm compared to the index screw value. While the morphologies of the load paths were similar in all cases, they differ between the two groups: the larger screw responded with generally elevated stiffer path than the smaller screw, suggesting that revision surgery using a larger screw has more purchase along the inserted body-pedicle axis.
Conclusions
A larger screw enhances strength and increases biomechanical stability in revision surgeries, although the final surgical decision is made by the clinician, which includes the patient’s anatomy and associated characteristics.
6.Antibacterial activity of some actinomycetes from Tamil Nadu, India.
Pachaiyappan Saravana KUMAR ; John Poonga Preetam RAJ ; Veeramuthu DURAIPANDIYAN ; Savarimuthu IGNACIMUTHU
Asian Pacific Journal of Tropical Biomedicine 2012;2(12):936-943
OBJECTIVETo isolate novel actinomycetes and to evaluate their antibacterial activity.
METHODSThree soil samples were collected from Vengodu (village) in Kanchipuram district, Tamil Nadu, India. Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar.
RESULTSTotally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar. All the isolates were screened for antibacterial activity by cross streak method. Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method. Isolation of bioactive compounds from significant active isolates was done by using different media. The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) using 16s rRNA sequence method. The hexane, ethyl acetate, dichloromethane and butanol extracts of VAS 10 were tested against bacteria. The maximum antibacterial activity was observed in dichloromethane and ethyl acetate; maximum zones of inhibition were observed against Enterococcus durans. The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively.
CONCLUSIONSThe present study showed that among the isolated actinomycetes, Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) showed good antibacterial activity against the tested bacteria.
Actinobacteria ; chemistry ; isolation & purification ; physiology ; Animals ; Anti-Bacterial Agents ; pharmacology ; Antibiosis ; physiology ; Bacillus subtilis ; drug effects ; Enterobacter aerogenes ; drug effects ; Escherichia coli ; drug effects ; India ; Microbial Sensitivity Tests ; Phylogeny ; RNA, Ribosomal, 16S ; genetics ; Soil Microbiology ; Species Specificity ; Vibrio parahaemolyticus ; drug effects
7.Pullout Strength Predictor: A Machine Learning Approach
Ravi KHATRI ; Vicky VARGHESE ; Sunil SHARMA ; Gurunathan Saravana KUMAR ; Harvinder Singh CHHABRA
Asian Spine Journal 2019;13(5):842-848
STUDY DESIGN: A biomechanical study. PURPOSE: To develop a predictive model for pullout strength. OVERVIEW OF LITERATURE: Spine fusion surgeries are performed to correct joint deformities by restricting motion between two or more unstable vertebrae. The pedicle screw provides a corrective force to the unstable spinal segment and arrests motions at the unit that are being fused. To determine the hold of a screw, surgeons depend on a subjective perioperative feeling of insertion torque. The objective of the paper was to develop a machine learning based model using density of foam, insertion angle, insertion depth, and reinsertion to predict the pullout strength of pedicle screw. METHODS: To predict the pullout strength of pedicle screw, an experimental dataset of 48 data points was used as training data to construct a model based on different machine learning algorithms. A total of five algorithms were tested in the Weka environment and the performance was evaluated based on correlation coefficient and error matrix. A sensitive study of various parameters for obtaining the best combination of parameters for predicting the pullout strength was also preformed using the L9 orthogonal array of Taguchi Design of Experiments. RESULTS: Random forest performed the best with a correlation coefficient of 0.96, relative absolute error of 0.28, and root relative squared error of 0.29. The difference between the experimental and predicted value for the six test cases was not significant (p >0.05). CONCLUSIONS: This model can be used clinically for understanding the failure of pedicle screw pullout and pre-surgical planning for spine surgeon.
8.Modulatory effect of distillate of Ocimum sanctum leaf extract (Tulsi) on human lymphocytes against genotoxicants.
Dipanwita DUTTA ; S Saravana DEVI ; K KRISHNAMURTHI ; Koel KUMAR ; Priyanka VYAS ; P L MUTHAL ; P NAOGHARE ; T CHAKRABARTI
Biomedical and Environmental Sciences 2007;20(3):226-234
OBJECTIVETo study the modulatory effect of distillate of Ocimum sanctum (traditionally known as Tulsi) leaf extract (DTLE) on genotoxicants.
METHODSIn the present investigation, we studied the antigenotoxic and anticlastogenic effect of distillate of Tulsi leaf extract on (i) human polymorphonuclear leukocytes by evaluating the DNA strand break without metabolic activation against mitomycin C (MMC) and hexavalent chromium (Cr+6) and (ii) human peripheral lymphocytes (in vitro) with or without metabolic activation against mitomycin C (MMC), hexavalent chromium (Cr+6) and B[a]P by evaluating chromosomal aberration (CA) and micronucleus assay (MN). Three different doses of DTLE, 50 microL/mL, 100 microL/mL, and 200 microL/mL were selected on the basis of cytotoxicity assay and used for studying DNA strand break, chromosomal aberration and micronucleus emergence. The following positive controls were used for inducing genotoxicity and clastogenicity: MMC (0.29 micromol/L) for DNA strand break, chromosomal aberration and 0.51 micromol/L for micronucleus assay; Potassium dichromate (Cr+6) 600 micromol/L for DNA strand break and 5 micromol/L for chromosomal aberration and micronucleus assay; Benzo[a]pyrene (30 micromol/L) for chromosomal aberration and 40 micromol/L for micronucleus assay. The active ingredients present in the distillate of Tulsi leaf extract were identified by HPLC and LC-MS.
RESULTSMitomycin C (MMC) and hexavalent chromium (Cr+6) induced statistically significant DNA strand break of respectively 69% and 71% (P<0.001) as revealed by fluorometric analysis of DNA unwinding. Furthermore, the damage could be protected with DTLE (50 microL/mL, 100 microL/mL, and 200 microL/mL) on simultaneous treatment. Chromosomal aberration and micronucleus formation induced by MMC, Cr+6 and B[a]P were significantly protected (P<0.001) by DTLE with and without metabolic activation.
CONCLUSIONDistillate of Tulsi leaf extract possesses antioxidants contributed mainly by eugenol, luteolin and apigenin as identified by LC-MS. These active ingredients may have the protective effect against genotoxicants.
Adult ; Benzopyrenes ; toxicity ; Cell Survival ; drug effects ; Chromium ; toxicity ; Chromosome Aberrations ; drug effects ; DNA ; metabolism ; DNA Damage ; drug effects ; Humans ; Lymphocytes ; drug effects ; Mass Spectrometry ; Mitomycin ; toxicity ; Mutagens ; toxicity ; Ocimum ; chemistry ; Plant Extracts ; pharmacology ; Plant Leaves ; chemistry
9.Usage of Health Information Websites: A Systematic Review of Older Adults’ Preferences for Web Features (Penggunaan Laman Web Maklumat Kesihatan: Kajian Sistematik Pilihan Warga Emas terhadap Ciri-ciri Laman Web)
NG CHEAH PING ; DEVINDER KAUR AJIT SINGH ; TAN MAW PIN ; SARAVANA KUMAR
Malaysian Journal of Health Sciences 2021;19(No.2):115-127
Online health information have a role in enhancing health in older adults. However, age-related physiological changes
and non-senior friendly websites proved to be a challenge for older adults. Research investigating older adults’ preferences
of features in health information websites is limited. Thus, in this review, we aim to summarize older adults’ preferences
regarding the design and content of health websites. Medline, CINAHL, Cochrane Library, Scopus, Journal of Medical
Internet Research (JMIR) and Google Scholar were searched for relevant articles in February 2018, using key words
‘older adults’, ‘Internet’, ‘health information’ and ‘usability’. The methodological quality of included studies was
evaluated using the McMaster critical appraisal tools by two independent reviewers. Individual study design, participants’
characteristics, and identified preferences for health website features were extracted and summarized narratively.
(PROSPERO registration number: CRD42018096281). Five studies (3 qualitative, 2 quantitative) were included in this
review. The quality appraisal score ranged from 32% to 83%. The web feature preferences of older adults were grouped
into three domains: web presentation factors, web navigation factors and health information preferences. The results
highlight older adults have specific preferences when engaging with online content. This review suggests that readable
text, simple design, consistent layout and straightforward web navigation are the preferred priorities for a health
information website for older adults. Findings from this review may be useful to healthcare professionals and developers
to understand older adults’ preferences pertaining to web design and contents in health websites specifically designed
for this population.
10.Impact of a Tailored Self-Management Education Programme for Older Adults with Knee Osteoarthritis in a Multi-Ethnic Country
SITI SALWANA KAMSAN ; DEVINDER KAUR AJIT SINGH ; MAW PIN TAN ; SARAVANA KUMAR
Malaysian Journal of Health Sciences 2024;22(No.1):97-106
Self-management education program (SMEP) is essential in the knee osteoarthritis (OA) management. While the benefits
of tailored SMEP have been highlighted in the literature, evidence on the effects of tailored knee OA SMEP for multiethnic populations, such as in Malaysia, remains limited. Therefore, the aim of this study was to conduct an intervention
study on a tailored SMEP among Malaysian older adults who aged 60 years and above with knee OA. Participants aged
60 years and over with a diagnosis of knee OA were recruited. The intervention comprised four weekly structured group
SMEP which was developed specifically for the multicultural population in Malaysia. Symptom’s severity and functional
performance were assessed at baseline and six-week follow-up using the Knee Injury and Osteoarthritis Outcome Score
questionnaire (KOOS), 30 seconds sit to stand (30sST), time up and go (TUG), chair sit and reach (CSR), back stretch
(BS), handgrip strength (HGS) and two-minute walk (2MW) tests. Of the 32 individuals recruited, 30 participants, mean
age of 66.77 (±6.42) years, completed the post-intervention assessment. Improvements in mean KOOS domains scores
were observed by between 1.3% - 8.6% from baseline to follow-up. Significant differences between baseline and followup scores were identified for 30sST (p < 0.05), TUG ( p < 0.001) and 2MW (p < 0.001) tests. A 4-week tailored SMEP
delivered face to face by a physiotherapist, improved lower limb muscle strength, mobility, balance and endurance.
Larger randomized controlled trials regarding the long-term effects of SMEP for older adults with OA is warranted.