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Penile prosthesis implantation in a transsexual neophallus

Tan HM

Asian J Androl, 2000 Dec;2(4):304-6.
PMID: 11202422

Reconstruction surgery for a female to male transsexual usually involves mastectomy, hysterectomy and creating an aesthetically appealing neophallus. We have successfully inserted an inflatable prosthesis using the AMS CX prosthesis in a 45 year old transsexual, who had a large bulky neophallus constructed from the anterior abdominal subcutaneous fat, about 9 years ago. The single cylinder CX prosthesis was well anchored to the symphysis pubis using a dacron windsock tubing, the activation pump was placed in the dependent pouch of the right labium and the reservior in the usual perivesical space. The patient subsequently had debulking procedure using liposuction to create a more aesthetic and functional phallus. To date, the inflatable neophallus prosthesis is functioning well.

Matched MeSH terms: Gynecologic Surgical Procedures/methods*; Reconstructive Surgical Procedures/methods*
Numerical simulation of normal and cancer cells' populations with fractional derivative under radiotherapy

Farayola MF, Shafie S, Mohd Siam F, Khan I

Comput Methods Programs Biomed, 2020 Apr;187:105202.
PMID: 31835107 DOI: 10.1016/j.cmpb.2019.105202

Background This paper presents a numerical simulation of normal and cancer cells' population dynamics during radiotherapy. The model used for the simulation was the improved cancer treatment model with radiotherapy. The model simulated the population changes during a fractionated cancer treatment process. The results gave the final populations of the cells, which provided the final volumes of the tumor and normal cells. Method The improved model was obtained by integrating the previous cancer treatment model with the Caputo fractional derivative. In addition, the cells' population decay due to radiation was accounted for by coupling the linear-quadratic model into the improved model. The simulation of the treatment process was done with numerical variables, numerical parameters, and radiation parameters. The numerical variables include the populations of the cells and the time of treatment. The numerical parameters were the model factors which included the proliferation rates of cells, competition coefficients of cells, and perturbation constant for normal cells. The radiation parameters were clinical data based on the treatment procedure. The numerical parameters were obtained from the previous literature while the numerical variables and radiation parameters, which were clinical data, were obtained from reported data of four cancer patients treated with radiotherapy. The four cancer patients had tumor volumes of 28.4 cm3, 18.8 cm3, 30.6 cm3, and 12.6 cm3 and were treated with different treatment plans and a fractionated dose of 1.8 Gy each. The initial populations of cells were obtained by using the tumor volumes. The computer simulations were done with MATLAB. Results The final volumes of the tumors, from the results of the simulations, were 5.67 cm3, 4.36 cm3, 5.74 cm3, and 6.15 cm3 while the normal cells' volumes were 28.17 cm3, 18.68 cm3, 30.34 cm3, and 12.54 cm3. The powers of the derivatives were 0.16774, 0.16557, 0.16835, and 0.16. A variance-based sensitivity analysis was done to corroborate the model with the clinical data. The result showed that the most sensitive factors were the power of the derivative and the cancer cells' proliferation rate. Conclusion The model provided information concerning the status of treatments and can also predict outcomes of other treatment plans.

Matched MeSH terms: Radiotherapy/methods*; Radiotherapy Planning, Computer-Assisted/methods
Seroprevalence of sarcocystosis in the local communities of Pangkor and Tioman Islands using recombinant surface antigens 3 (rSAG3) of Sarcocystis falcatula

Tengku-Idris TIN, Fong MY, Lau YL

Trop Med Int Health, 2018 12;23(12):1374-1383.
PMID: 30286271 DOI: 10.1111/tmi.13160

OBJECTIVE: To investigate the seroprevalence of Sarcocystosis in the local communities of Pangkor and Tioman islands, Malaysia, by using antigenic recombinant surface antigens 2 and 3 from Sarcocystis falcatula (rSfSAG2 and rSfSAG3) as the target proteins via Western blot and ELISA assays.
METHODS: SfSAG2 and SfSAG3 genes were isolated from S. falcatula and expressed in Escherichia coli expression system. A total of 348 serum samples [volunteers from both islands (n = 100), non-Sarcocystis parasitic infections patients (n = 50) and healthy donors (n = 100)] were collected and tested with purified SfSAGs in Western blot and ELISA assays to measure the seroprevalence of human sarcocystosis.
RESULTS: None of the sera in this study reacted with rSfSAG2 by Western blot and ELISA. For rSfSAG3, relatively high prevalence of sarcocystosis was observed in Tioman Island (75.5%) than in Pangkor Island (34%) by Western blot. In ELISA, the different prevalence rate was observed between Tioman Island (43.8%) and Pangkor Island (37%). The prevalence rate in other parasitic infections (amoebiasis, cysticercosis, filariasis, malaria, toxocariasis and toxoplasmosis) was 30% by Western blot and 26% by ELISA. Only 8% (by Western blot) and 10% (by ELISA) of healthy donors showed reactivity towards rSfSAG3.
CONCLUSION: This is the first study reporting a seroprevalence of sarcocystosis in Pangkor and Tioman Islands, Malaysia. The combination of Western blot and ELISA is suitable to be used for serodiagnosis of sarcocystosis. With further evaluations, SfSAG3 can potentially be used to confirm infection, asymptomatic screening, surveillance and epidemiological studies.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods; Blotting, Western/methods
Fulltext Reduction in Urinary Chemokine (C-C Motif) Ligand 2 (CCL2) After Surgery-Induced Weight Loss

Said SB, Loo GH, Kosai NR, Rajan R, Mohd R, Wahab AA, et al.

Sci Rep, 2020 01 21;10(1):790.
PMID: 31964990 DOI: 10.1038/s41598-020-57763-8

Kidney dysfunction, a deleterious effect of obesity, is now recognized as a relevant health risk. Chemokine (C-C Motif) Ligand 2 (CCL2) is one of the critical chemokines that play a vital role in the development of obesity-related metabolic disease. We aim to measure the changes in urinary CCL2 in our patients before and after their bariatric procedure and examine the correlation between CCL2 and renal function. A prospective cohort study was conducted at our teaching university hospital. Ethics approval was obtained from our institutional review board. Patients with a BMI of ≥37.5 kg/m2 with no history of renal disease were included. They underwent single anastomosis gastric bypass (SAGB), Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG), all performed via laparoscopic approach. Venous blood and urine samples were obtained preoperatively and six months after surgery. A total of 58 patients were recruited, with SG being performed in 74.1% of patients. At six-months follow-up, median (IQR) body weight reduced from 101.35 kgs (20.25) to 76.95 kg (24.62) p

Matched MeSH terms: Gastrectomy/methods; Gastric Bypass/methods*
Activity analysis of thermal imaging videos using a difference imaging approach

Tattersall GJ, Danner RM, Chaves JA, Levesque DL

J Therm Biol, 2020 Jul;91:102611.
PMID: 32716861 DOI: 10.1016/j.jtherbio.2020.102611

Infrared thermal imaging is a passive imaging technique that captures the emitted radiation from an object to estimate surface temperature, often for inference of heat transfer. Infrared thermal imaging offers the potential to detect movement without the challenges of glare, shadows, or changes in lighting associated with visual digital imaging or active infrared imaging. In this paper, we employ a frame subtraction algorithm for extracting the pixel-by-pixel relative change in signal from a fixed focus video file, tailored for use with thermal imaging videos. By summing the absolute differences across an entire video, we are able to assign quantitative activity assessments to thermal imaging data for comparison with simultaneous recordings of metabolic rates. We tested the accuracy and limits of this approach by analyzing movement of a metronome and provide an example application of the approach to a study of Darwin's finches. In principle, this "Difference Imaging Thermography" (DIT) would allow for activity data to be standardized to energetic measurements and could be applied to any radiometric imaging system.

Matched MeSH terms: Thermography/methods*; Video Recording/methods*
Fulltext Pre-extinction Demographic Stability and Genomic Signatures of Adaptation in the Woolly Rhinoceros

Lord E, Dussex N, Kierczak M, Díez-Del-Molino D, Ryder OA, Stanton DWG, et al.

Curr Biol, 2020 10 05;30(19):3871-3879.e7.
PMID: 32795436 DOI: 10.1016/j.cub.2020.07.046

Ancient DNA has significantly improved our understanding of the evolution and population history of extinct megafauna. However, few studies have used complete ancient genomes to examine species responses to climate change prior to extinction. The woolly rhinoceros (Coelodonta antiquitatis) was a cold-adapted megaherbivore widely distributed across northern Eurasia during the Late Pleistocene and became extinct approximately 14 thousand years before present (ka BP). While humans and climate change have been proposed as potential causes of extinction [1-3], knowledge is limited on how the woolly rhinoceros was impacted by human arrival and climatic fluctuations [2]. Here, we use one complete nuclear genome and 14 mitogenomes to investigate the demographic history of woolly rhinoceros leading up to its extinction. Unlike other northern megafauna, the effective population size of woolly rhinoceros likely increased at 29.7 ka BP and subsequently remained stable until close to the species' extinction. Analysis of the nuclear genome from a ∼18.5-ka-old specimen did not indicate any increased inbreeding or reduced genetic diversity, suggesting that the population size remained steady for more than 13 ka following the arrival of humans [4]. The population contraction leading to extinction of the woolly rhinoceros may have thus been sudden and mostly driven by rapid warming in the Bølling-Allerød interstadial. Furthermore, we identify woolly rhinoceros-specific adaptations to arctic climate, similar to those of the woolly mammoth. This study highlights how species respond differently to climatic fluctuations and further illustrates the potential of palaeogenomics to study the evolutionary history of extinct species.

Matched MeSH terms: Archaeology/methods*; Genomics/methods
Diagnosis, impact and management of hyperhidrosis including endoscopic thoracic sympathectomy

Ho YL, Fauzi M, Sothee K, Basheer A

Med J Malaysia, 2020 09;75(5):555-560.
PMID: 32918426

INTRODUCTION: Hyperhidrosis is a disorder of excessive and uncontrollable sweating beyond the body's physiological needs. It can be categorised into primary or secondary hyperhidrosis based on its aetiology. Detailed history review including onset of symptoms, laterality of disease and family history are crucial which may suggest primary hyperhidrosis. Secondary causes such as neurological diseases, endocrine disorders, haematological malignancies, neuroendocrine tumours and drugs should be adequately examined and investigated prior to deciding on further management. The diagnosis of primary hyperhidrosis should only be made only after excluding secondary causes. Hyperhidrosis is a troublesome disorder that often results in social, professional, and psychological distress in sufferers. It remains, however, a treatment dilemma among some healthcare providers in this region.
METHODS: The medical records and clinical outcomes of 35 patients who underwent endoscopic thoracic sympathectomy for primary hyperhidrosis from 2008 to 2018 in Department of Cardiothoracic Surgery were reviewed.
RESULTS: The mean age of the patients was 27±10.1years, with male and female distribution of 18 and 17, respectively. Fifty-one percent of patients complained of palmar hyperhidrosis, while 35% of them had concurrent palmaraxillary and 14% had palmar-plantar-axillary hyperhidrosis. Our data showed that 77% (n=27) of patients were not investigated for secondary causes of hyperhidrosis, and they were not counselled on the non-surgical therapies. All patients underwent single-staged bilateral endoscopic thoracic sympathectomy. There was resolution of symptoms in all 35 (100%) patients with palmar hyperhidrosis, 13(76%) patients with axillary hyperhidrosis and only 2 (50%) patients with plantar hyperhidrosis. Postoperatively 34.3% (n=12) of patients reported compensatory hyperhidrosis. There were no other complications such as pneumothorax, chylothorax, haemothorax and Horner's Syndrome.
CONCLUSION: Clinical evaluation of hyperhidrosis in local context has not been well described, which may inadvertently result in the delay of appropriate management, causing significant social and emotional embarrassment and impair the quality of life of the subjects. Detailed clinical assessment and appropriate timely treatment, be it surgical or non-surgical therapies, are crucial in managing this uncommon yet distressing disease.

Matched MeSH terms: Sympathectomy/methods*; Thoracoscopy/methods*
Fulltext Ketamine-propofol (Ketofol) for procedural sedation and analgesia in children: a systematic review and meta-analysis

Foo TY, Mohd Noor N, Yazid MB, Fauzi MH, Abdull Wahab SF, Ahmad MZ

BMC Emerg Med, 2020 10 08;20(1):81.
PMID: 33032544 DOI: 10.1186/s12873-020-00373-4

OBJECTIVES: The aim of this review is to elucidate the efficacy and side effects of ketofol in comparison to other anaesthetic agents during procedural sedation and analgesia.
METHOD: The Cochrane Central Register of Controlled Trials (1996 to Feb 2019) and MEDLINE (1966 to Feb 2019) were searched, including the related randomised control trials and reviewed articles to find unpublished trials or trials not obtained via electronic searches. Inclusion criteria for the studies included comparing recovery time, recording clinician satisfaction, and assessing the adverse effects of ketofol.
RESULTS: Eleven trials consisting of a total of 1274 patients met our criteria and were included in this meta-analysis. Five trials compared ketofol with a single agent, while six trials compared ketofol with combined agents. While comparing between ketofol and a single agent (either ketamine or propofol), ketofol showed significant effect on recovery time (MD: -9.88, 95% CI: - 14.30 to - 5.46; P = 0.0003; I2 = 92%). However, no significant difference was observed while comparing ketofol with combined agents (RR: 0.75, 95% CI: - 6.24 to 7.74; P < 0.001; I2 = 98%). During single-agent comparison, ketofol showed no significant differences in terms of clinician satisfaction (RR: 2.86, 95% CI: 0.64 to 12.69; P = 0.001; I2 = 90%), airway obstruction (RR: 0.72, 95% CI: 0.35 to 11.48; P = 0.81; I2 = 0%), apnoea (RR: 0.9, 95% CI: 0.33 to 2.44; P = 0.88; I2 = 0%), desaturation (RR: 1.11, 95% CI: 0.64 to 1.94; P = 0.28; I2 = 21%), nausea (RR: 0.52, 95% CI: 0.91 to 1.41; P = 0.2; I2 = 38%), and vomiting (RR: 0.63, 95% CI: 0.25 to 1.61; P = 0.18; I2 = 42%). During comparison with combined agents, ketofol was more effective in reducing hypotension (RR: 4.2, 95% CI: 0.2 to 0.85; P = 0.76; I2 = 0%), but no differences were observed in terms of bradycardia (RR: 0.70, 95% CI: 0.14 to 03.63; P = 0.09; I2 = 53%), desaturation (RR: 1.9, 95% CI: 0.15 to 23.6; P = 0.11; I2 = 61%), and respiratory depression (RR: 1.98, 95% CI: 0.18 to 21.94; P = 0.12; I2 = 59%).
CONCLUSION: There is low certainty of evidence that ketofol improves recovery time and moderate certainty of evidence that it reduces the frequency of hypotension. There was no significant difference in terms of other adverse effects when compared to other either single or combined agents.
TRIAL REGISTRATION: PROSPERO CRD42019127278 .

Matched MeSH terms: Conscious Sedation/methods; Pain Management/methods*
Fulltext Evaluation of WarmStart Colorimetric Loop-Mediated Isothermal Amplification Assay for Diagnosis of Malaria

Lai MY, Ooi CH, Jaimin JJ, Lau YL

Am J Trop Med Hyg, 2020 06;102(6):1370-1372.
PMID: 32228783 DOI: 10.4269/ajtmh.20-0001

The incidence of zoonotic malaria, Plasmodium knowlesi, infection is increasing and now is the major cause of malaria in Malaysia. Here, we describe a WarmStart colorimetric loop-mediated isothermal amplification (LAMP) assay for the detection of Plasmodium spp. The detection limit for this assay was 10 copies/µL for P knowlesi and Plasmodium ovale and 1 copy/µL for Plasmodium falciparum, Plasmodium vivax, and Plasmodium malariae. To test clinical sensitivity and specificity, 100 microscopy-positive and 20 malaria-negative samples were used. The WarmStart colorimetric LAMP was 98% sensitive and 100% specific. Amplification products were visible for direct observation, thereby eliminating the need for post-amplification processing steps. Therefore, WarmStart colorimetric LAMP is suitable for use in resource-limited settings.

Matched MeSH terms: Colorimetry/methods*; Nucleic Acid Amplification Techniques/methods*
An electrochemical DNA biosensor fabricated from graphene decorated with graphitic nanospheres

Raja Jamaluddin RZA, Tan LL, Chong KF, Heng LY

Nanotechnology, 2020 Nov 27;31(48):485501.
PMID: 32748805 DOI: 10.1088/1361-6528/abab2e

Graphene decorated with graphitic nanospheres functionalized with pyrene butyric acid (PBA) is used for the first time to fabricate a DNA biosensor. The electrode was formed by attaching a DNA probe onto PBA, which had been stacked onto a graphene material decorated with graphene nanospheres (GNSs). The nanomaterial was drop-coated onto a carbon screen-printed electrode (SPE) to create the GNS-PBA modified electrode (GNS-PBA/SPE). A simple method was used to produce GNS by annealing graphene oxide (GO) solution at high temperature. Field emission scanning electron micrographs confirmed the presence of a spherical shape of GNS with a diameter range of 40-80 nm. A stable and uniform PBA-modified GNS (GNS-PBA) was obtained with a facile ultrasonication step. Thus allowing aminated DNA probes of genetically modified (GM) soybean to be attached to the nanomaterials to form the DNA biosensor. The GNS-PBA/SPE exhibited excellent electrical conductivity via cyclic voltammetry (CV) and differential pulse voltammetry (DPV) tests using potassium ferricyanide (K3[Fe(CN)6]) as the electroactive probe. By employing an anthraquinone monosulfonic acid (AQMS) redox intercalator as the DNA hybridization indicator, the biosensor response was evaluated using the DPV electrochemical method. A good linear relationship between AQMS oxidation peak current and target DNA concentrations from 1.0 × 10-16 to 1.0 × 10-8 M with a limit of detection (LOD) of less than 1.0 × 10-16 M was obtained. Selectivity experiments revealed that the voltammetric GM DNA biosensor could discriminate complementary sequences of GM soybean from non-complementary sequences and hence good recoveries were obtained for real GM soybean sample analysis. The main advantage of using GNS is an improvement of the DNA biosensor analytical performance.

Matched MeSH terms: Biosensing Techniques/methods*; Electrochemical Techniques/methods
Fulltext Immunogenicity and protective efficacy of a live, oral cholera vaccine formulation stored outside-the-cold-chain for 140 days

Xian TH, Sinniah K, Yean CY, Krishnamoorthy V, Bahari MB, Ravichandran M, et al.

BMC Immunol, 2020 05 25;21(1):29.
PMID: 32450807 DOI: 10.1186/s12865-020-00360-1

BACKGROUND: Cholera, an acute watery diarrhoeal disease caused by Vibrio cholerae serogroup O1 and O139 across the continents. Replacing the existing WHO licensed killed multiple-dose oral cholera vaccines that demand 'cold chain supply' at 2-8 °C with a live, single-dose and cold chain-free vaccine would relieve the significant bottlenecks and cost determinants in cholera vaccination campaigns. In this direction, a prototype cold chain-free live attenuated cholera vaccine formulation (LACV) was developed against the toxigenic wild-type (WT) V. cholerae O139 serogroup. LACV was found stable and retained its viability (5 × 106 CFU/mL), purity and potency at room temperature (25 °C ± 2 °C, and 60% ± 5% relative humidity) for 140 days in contrast to all the existing WHO licensed cold-chain supply (2-8 °C) dependent killed oral cholera vaccines.
RESULTS: The LACV was evaluated for its colonization potential, reactogenicity, immunogenicity and protective efficacy in animal models after its storage at room temperature for 140 days. In suckling mice colonization assay, the LACV recorded the highest recovery of (7.2 × 107 CFU/mL) compared to those of unformulated VCUSM14P (5.6 × 107 CFU/mL) and the WT O139 strain (3.5 × 107 CFU/mL). The LACV showed no reactogenicity even at an inoculation dose of 104-106 CFU/mL in a rabbit ileal loop model. The rabbits vaccinated with the LACV or unformulated VCUSM14P survived a challenge with WT O139 and showed no signs of diarrhoea or death in the reversible intestinal tie adult rabbit diarrhoea (RITARD) model. Vaccinated rabbits recorded a 275-fold increase in anti-CT IgG and a 15-fold increase in anti-CT IgA antibodies compared to those of rabbits vaccinated with unformulated VCUSM14P. Vibriocidal antibodies were increased by 31-fold with the LACV and 14-fold with unformulated VCUSM14P.
CONCLUSION: The vaccine formulation mimics a natural infection, is non-reactogenic and highly immunogenic in vivo and protects animals from lethal wild-type V. cholerae O139 challenge. The single dose LACV formulation was found to be stable at room temperature (25 ± 2 °C) for 140 days and it would result in significant cost savings during mass cholera vaccination campaigns.

Matched MeSH terms: Refrigeration/methods; Vaccination/methods
Solid-phase extraction of non-steroidal anti-inflammatory drugs in human plasma and water samples using sol-gel-based metal-organic framework coating

Amiri A, Ghaemi F

J Chromatogr A, 2021 Jul 05;1648:462168.
PMID: 33984648 DOI: 10.1016/j.chroma.2021.462168

In this research, the Cu-based metal-organic framework (MOF-199) was fabricated and coated on the stainless steel mesh as substrates through sol-gel procedure. Then the coated substrates were placed in a small column known as solid-phase extraction cartridge. The SPE based coated stainless steel mesh coupled with high-performance liquid chromatography-UV detector (HPLC-UV) was used for the fast extraction, and quantification of non-steroidal anti-inflammatory drugs (NSAIDs) from human plasma and water samples. To find optimum extraction conditions, the impacts of effective parameters on analytical performance like sample pH, sample volume, type, and volume of desorption solvent were optimized. At the optimized conditions, calibration graphs of analytes were linear in the concentration range of 0.03-300 ng mL-1 for water samples, and 0.1-200 ng mL-1 for plasma samples. The correlation coefficients were in the range of 0.9938 to 0.9989. Also, the limits of detection (LODs) were from 0.01 to 0.02 ng mL-1 for water samples and 0.03 to 0.1 ng mL-1 for plasma samples. The cartridge repeatability was studied at different values, and the relative standard deviations (RSDs%) were achieved between 3.5 and 5.1%. Consequently, this procedure was successfully used in the extraction and detection of NSAIDs in real water and plasma samples with relative recoveries ranged from 93.6 to 99.6%.

Matched MeSH terms: Chromatography, High Pressure Liquid/methods; Solid Phase Extraction/methods*
Controlled release compound based on metanilate-layered double hydroxide nanohybrid

Hussein MZ, Nasir NM, Yahaya AH

J Nanosci Nanotechnol, 2008 Nov;8(11):5921-8.
PMID: 19198327

Metanilate-layered double hydroxide nanohybrid compound was synthesized for controlled release purposes through co-precipitation method of the metal cations and organic anion. The effect of various divalent metal cations (M2+), namely Zn2+, Mg2+ and Ca2+ on the formation of metanilate-LDH nanohybrids, in which metanilate anion was intercalated into three different layered double hydroxide (LDH) systems; Zn-Al, Mg-Al and Ca-Al were investigated. The syntheses were carried out with M2+ to Al3+ initial molar ratio, R of 4. The pH of the mother liquor was maintained at pH 7.5 and 10 during the synthesis, and the resulting mixture was aged at around 70 degrees C for about 18 h. The intercalation of metanilate anion into the host was found to be strongly influenced by the M2+ that formed the inorganic metal hydroxide layers. Under our experimental condition, the formation of the nanohybrid materials was found to be more feasible for the Zn-Al than for the other two systems, in which the former showed well-ordered layered organic-inorganic nanohybrid structure with good crystallinity. Intercalation is confirmed by the expansion of the interlayer spacing to about 15-17 A when metanilate was introduced into the interlamellae of Zn-Al LDHs. In addition, CHNS and FTIR analyses also support that metanilate anion has been successfully intercalated into the interlamellae of the inorganic LDH. Apart from M2+, this study also shows that the initial pH of the mother liquor plays an important role in determining the physicochemical properties of the resulting nanohybrids, especially the mole fraction of the Zn2+ substituted by the Al3+ ion in the LDH inorganic sheets which in turn controlled the loading percentage of the organic anion, surface properties and the true density. Preliminary study shows that LDH can be used to host beneficial guests, active agent with controlled release capability of the guests. Generally the overall process is governed by pseudo second order kinetic but for the first 180 min, the release process can be slightly better described by parabolic diffusion than the other models.

Matched MeSH terms: Crystallization/methods*; Nanotechnology/methods*
Synthesis and characterization of polymeric V2O5/AlO(OH) with nanopores on alumina support

Ahmad AL, Abd Shukor SR, Leo CP

J Nanosci Nanotechnol, 2006 Dec;6(12):3910-4.
PMID: 17256351

Polymeric vanadium pentoxide gel was formed via the reaction of V2O5 powder with hydrogen peroxide. The polymeric vanadium pentoxide gel was then dispersed in alumina gel. Different vanadium loading composites were coated on alumina support and calcined at 500 degrees C for 1 hr. These composite layers were characterized using TGA, FT-IR, XRD, SEM, and Autosorb. It was found that the lamellar structure of polymerized vanadium pentoxide was retained in the inorganic matrix. Crystalline alumina in gamma phase was formed after calcinations. However, the vanadium-alumina mixed oxides are lack of the well defined PXRD peaks for polycrystalline V2O5. This is possibly because the vanadia species are highly dispersed in the alumina matrix or the vanadia species are dispersed as crystalline which is smaller than 4 nm. In addition, the imbedded polymeric vanadium oxide improved the specific area and average pore diameter of the composite layer.

Matched MeSH terms: Crystallization/methods*; Nanotechnology/methods*
Substrate effects on surface morphologies and magnetic properties of nanostructured FePt thin films

Low PL, Yong BE, Ong BH, Matsumoto M, Tou TY

J Nanosci Nanotechnol, 2011 Mar;11(3):2640-3.
PMID: 21449444

The substrate effects on surface morphologies, crystal structures, and magnetic properties of the sputter-deposited FePt thin films on Corning 1737, normal glass, and Si wafer substrates, respectively, were investigated. High in-plane coercivities of 10 kOe were obtained for the air-annealed films on Corning 1737 and Si wafer, where both films similarly have granular-like morphologies. Besides, increasing grain size and surface roughness of all the FePt films with the post-anneal temperature were observed. Moreover, partially separated grains were seen in the film on Si wafer, where the formation of Fe silicides during post-anneal is suspected, in which has enhanced the magnetic ordering.

Matched MeSH terms: Crystallization/methods; Nanotechnology/methods
Observation of a cubical-like microstructure of strontium iron garnet and yttrium iron garnet prepared via sol-gel technique

Nasir N, Yahya N, Kashif M, Daud H, Akhtar MN, Zaid HM, et al.

J Nanosci Nanotechnol, 2011 Mar;11(3):2551-4.
PMID: 21449424

This is our initial response towards preparation of nano-inductors garnet for high operating frequencies strontium iron garnet (Sr3Fe5O12) denoted as SrIG and yttrium iron garnet (Y3Fe5O12) denoted as YIG. The garnet nano crystals were prepared by novel sol-gel technique. The phase and crystal structure of the prepared samples were identified by using X-ray diffraction analysis. SEM images were done to reveal the surface morphology of the samples. Raman spectra was taken for yttrium iron garnet (Y3Fe5O12). The magnetic properties of the samples namely initial permeability (micro), relative loss factor (RLF) and quality factor (Q-Factor) were done by using LCR meter. From the XRD profile, both of the Y3Fe5O12 and Sr3Fe5O12 samples showed single phase garnet and crystallization had completely occurred at 900 degrees C for the SrIG and 950 degrees C for the YIG samples. The YIG sample showed extremely low RLF value (0.0082) and high density 4.623 g/cm3. Interesting however is the high Q factor (20-60) shown by the Sr3Fe5O12 sample from 20-100 MHz. This high performance magnetic property is attributed to the homogenous and cubical-like microstructure. The YIG particles were used as magnetic feeder for EM transmitter. It was observed that YIG magnetic feeder with the EM transmitter gave 39% higher magnetic field than without YIG magnetic feeder.

Matched MeSH terms: Crystallization/methods*; Nanotechnology/methods
A review on polyamide thin film nanocomposite (TFN) membranes: History, applications, challenges and approaches

Lau WJ, Gray S, Matsuura T, Emadzadeh D, Chen JP, Ismail AF

Water Res, 2015 Sep 1;80:306-24.
PMID: 26011136 DOI: 10.1016/j.watres.2015.04.037

This review focuses on the development of polyamide (PA) thin film nanocomposite (TFN) membranes for various aqueous media-based separation processes such as nanofiltration, reverse osmosis and forward osmosis since the concept of TFN was introduced in year 2007. Although the total number of published TFN articles falls far short of the articles of the well-known thin film composite (TFC) membranes, its growth rate is significant, particularly since 2012. Generally, by incorporating an appropriate amount of nanofiller into a thin selective PA layer of a composite membrane, one could produce TFN membranes with enhanced separation characteristics as compared to the conventional TFC membrane. For certain cases, the resulting TFN membranes demonstrate not only excellent antifouling resistance and/or greater antibacterial effect, but also possibly overcome the trade-off effect between water permeability and solute selectivity. Furthermore, this review attempts to give the readers insights into the difficulties of incorporating inorganic nanomaterials into the organic PA layer whose thickness usually falls in a range of several-hundred nanometers. It is also intended to show new possible approaches to overcome these challenges in TFN membrane fabrication.

Matched MeSH terms: Filtration/methods; Water Purification/methods*
Biosensing based on surface-enhanced Raman spectroscopy as an emerging/next-generation point-of-care approach for acute myocardial infarction diagnosis

Low JSY, Thevarajah TM, Chang SW, Goh BT, Khor SM

Crit Rev Biotechnol, 2020 Dec;40(8):1191-1209.
PMID: 32811205 DOI: 10.1080/07388551.2020.1808582

Cardiovascular disease is a major global health issue. In particular, acute myocardial infarction (AMI) requires urgent attention and early diagnosis. The use of point-of-care diagnostics has resulted in the improved management of cardiovascular disease, but a major drawback is that the performance of POC devices does not rival that of central laboratory tests. Recently, many studies and advances have been made in the field of surface-enhanced Raman scattering (SERS), including the development of POC biosensors that utilize this detection method. Here, we present a review of the strengths and limitations of these emerging SERS-based biosensors for AMI diagnosis. The ability of SERS to multiplex sensing against existing POC detection methods are compared and discussed. Furthermore, SERS calibration-free methods that have recently been explored to minimize the inconvenience and eliminate the limitations caused by the limited linear range and interassay differences found in the calibration curves are outlined. In addition, the incorporation of artificial intelligence (AI) in SERS techniques to promote multivariate analysis and enhance diagnostic accuracy are discussed. The future prospects for SERS-based POC devices that include wearable POC SERS devices toward predictive, personalized medicine following the Fourth Industrial Revolution are proposed.

Matched MeSH terms: Spectrum Analysis, Raman/methods*; Biosensing Techniques/methods
Bioseparation of phycocyanin from Phormidium tergestinum using an aqueous two-phase system

Tan JS, Abbasiliasi S, Lalung J, Tam YJ, Murugan P, Lee CK

Prep Biochem Biotechnol, 2021;51(3):260-266.
PMID: 32876520 DOI: 10.1080/10826068.2020.1808793

This study aimed at purification of phycocyanin (PC) from Phormidium tergestinum using an aqueous two-phase system (ATPS) comprised of polyethylene glycol (PEG) and salts. The partitioning efficiency of PC in ATPS and the effect of phase composition, pH, crude loading, and neutral salts on purification factor and yield were investigated. Results showed that PC was selectively partitioned toward bottom phase of the system containing potassium phosphate. Under optimum conditions of 20% (w/w) PEG 4000, 10% (w/w) potassium phosphate, 20% (v/v) crude load at pH 7, with addition of 0.5% (w/w) NaCl, PC from P. tergestinum was partially purified up to 5.34-fold with a yield of 87.8%. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the molecular weight of PC was ∼19 kDa. Results from this study demonstrated ATPS could be used as a potential approach for the purification of PC from P. tergestinum.

Matched MeSH terms: Biotechnology/methods; Food Technology/methods
Fulltext Ultrasound Probe Positions for Internal Jugular Vein Cannulation: A Prospective Study of Different Techniques

Kurien M, Teo R, Zainuddin K, Azidin AM, Izaham A, Budiman M, et al.

Clin Ter, 2021 Jul 05;172(4):278-283.
PMID: 34247211 DOI: 10.7417/CT.2021.2332

Objective: We compared sonoanatomy of the internal jugular vein (IJV) the high (HA), conventional (CA) and the medial oblique approach (MA) to identify the best approach and head position for IJV cannulation.
Materials & Methods: Total of 45 volunteers aged 18-65 years were included in this study. The degree of overlap in percentage, depth of IJV from skin, antero-posterior (AP) and transverse diameters (TD) of IJV were measured in real time with ultrasound (US). Measurements were taken in the HA, CA and MA in neutral and 30° head rotation on both the right and left side of the neck.
Results: The HA had lower percentage of overlap when compared to CA and MA in neutral and 30° head rotation (p= 0.002 to ≤0.001). The IJV was more shallow in the CA and MA. The AP and TD of the IJV were larger in the MA when compared to HA (p=<0.001) and CA (p =0.026 to < 0.001) and the right IJV has a larger AP and TD in all approaches.
Discussion: The HA had the least percentage of overlap compared to CA and MA, therefore the risk of accidental ICA puncture can be reduced. The apparent overlap seen in MA may not reflect the actual scenario because of the way the US beam cuts the vessel. The AP and TD of IJV were significantly increased in the MA, which would ease CVC.
Conclusion: We conclude and recommend the medial oblique probe position with 30° head rotation provides optimal real time sonographic parameters for US guided IJV cannulation.

Matched MeSH terms: Catheterization, Central Venous/methods*; Ultrasonography/methods*

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