Boosted charge separation via Ce2S3 over dual Z-scheme ZnO-Ce2S3-MnO2 core double-shell nanocomposite for the degradation of diverse dye pollutants.

Herein, core double-shell direct dual Z-scheme ZnO-Ce2S3-MnO2 nanocomposite was synthesized via a hydrothermal route along with pure ZnO, Ce2S3, MnO2, and characterized by numerous characterization tools for application in synthetic dyes degradation. The XRD, Raman, and FTIR analyses have confirmed the nanocomposite formation. TEM images exhibited the core double-shell morphology with an average particle diameter of 81 nm and stacking of ZnO, Ce2S3, and MnO2. EDX confirmed the existence of desired elements in the grown composition. The varied oxidation states, presence of defects, and fast charge transfer were also revealed from XPS, PL, and EIS. The ZnO-Ce2S3-MnO2 nanocomposite has an optical energy bandgap of 2.84 eV, capable of decomposing harmful dyes with excellent efficiency, 99.81% MB, 97.62% MO, 88.5% MR, and 58.9% EY in 40 min sunlight exposure. The effect of several operating parameters is also observed and obtained results showed the optimal catalyst dose was 20 mg, pH of 8, and dye concentration of 10 ppm. The scavenger's experiment suggests that •O2- and •OH are the main active radicals in the photodegradation reaction which is also evident in the dual Z-scheme formation. The MnO2 and ZnO layers covered the Ce2S3 (core) and dual Z-scheme formation allows rapid kinetics of redox reaction and provides plenteous channels for transfer of photo-generated charge carriers during photocatalysis. Thus, core double-shell direct dual Z-scheme photocatalysts having inorganic components could be an excellent choice for photocatalysis at the industrial level, particularly for water purification.

Synergistic effect of a bamboo-like Bi2S3 covered Sm2O3 nanocomposite (Bi2S3-Sm2O3) for enhanced alkaline OER.

The availability of hydrogen energy from water splitting through the electrocatalytic route is strongly dependent on the efficiency, durability, and cost of the electrocatalysts. Herein, a novel Bi2S3-covered Sm2O3 (Bi2S3-Sm2O3) nanocomposite electrocatalyst was developed by a hydrothermal route for the oxygen evolution reaction (OER). The electrochemical properties were studied in 1.00 mol KOH solution after coating the target material on the stainless-steel substrate (SS). Physical analysis via XRD, FTIR, IV, TEM/EDX, and XPS revealed that the Bi2S3-Sm2O3 composite possesses metallic surface states, thereby displaying unconventional electron dynamics and purity of phases. The Bi2S3-Sm2O3 composite shows outstanding OER activity with a low overpotential of 197 mV and a Tafel slope of 74 mV dec-1 at a 10 mA cm-2 current density as compared to pure Bi2S3 and Sm2O3. Meanwhile, the composite catalyst retains high stability even after 100 h of the chronoamperometry test. Thus, this work unveils a new avenue for the speedy flow of electrons, which is attributed to the synergetic effect between Bi2S3 and Sm2O3, as well as enriched interfacial defects, which exhibit greater oxygen adsorption capability with improved electronic assemblies in the active interfacial region. In addition, the introduced porous structure in core-shell Bi2S3-Sm2O3 provides extraordinary electrical properties. Thus, this article offers a realistic framework for electrochemical energy generation.

Fabrication of fullerene-supported La2O3-C60 nanocomposites: dual-functional materials for photocatalysis and supercapacitor electrodes.

Nowadays, water pollution and energy crises worldwide force researchers to develop multi-functional and highly efficient nanomaterials. In this scenario, the present work reports a dual-functional La2O3-C60 nanocomposite fabricated by a simple solution method. The grown nanomaterial worked as an efficient photocatalyst and proficient electrode material for supercapacitors. The physical and electrochemical properties were studied by state-of-the-art techniques. XRD, Raman spectroscopy, and FTIR spectroscopy confirmed the formation of the La2O3-C60 nanocomposite with TEM nano-graphs, and EDX mapping exhibits the loading of C60 on La2O3 particles. XPS confirmed the presence of varying oxidation states of La3+/La2+. The electrochemical capacitive properties were tested by CV, EIS, GCD, ECSA, and LSV, which indicated that the La2O3-C60 nanocomposite can be effectively used as an electrode material for durable and efficient supercapacitors. The photocatalytic test using methylene blue (MB) dye revealed the complete photodegradation of the MB dye under UV light irradiation after 30 min by a La2O3-C60 catalyst with a reusability up to 7 cycles. The lower energy bandgap, presence of deep-level emissions, and lower recombination rate of photoinduced charge carriers in the La2O3-C60 nanocomposite than those of bare La2O3 are responsible for enhanced photocatalytic activity with low-power UV irradiation. The fabrication of multi-functional and highly efficient electrode materials and photocatalysts such as La2O3-C60 nanocomposites is beneficial for the energy industry and environmental remediation applications.

Dual Z-scheme core-shell PANI-CeO2-Fe2O3-NiO heterostructured nanocomposite for dyes remediation under sunlight and bacterial disinfection.

Nowadays, environmental pollution due to discharge of organic pollutants from food, textile, and pharmaceutical industries into clean water and development of contagious diseases due to pathogenic organisms provide impetus to material researcher to fabricate novel design for efficient photocatalyst and antimicrobial agents. In this regard, designing a core-shell heterojunction catalyst based on metal oxides is considered an auspicious approach. In present study, combating the problems of singular oxides, core-shell PANI-CeO2-Fe2O3-NiO nanocomposite (PCFN) and CeO2-Fe2O3-NiO nanocomposite (CFN) was synthesized through sol-gel and oxidative polymerization route with cetyletrimethylammonium bromide (CTAB) as surfactant. The XRD, FTIR, and Raman confirmed the formation of nanocomposites with core-shell morphology composed of PANI (shell) and oxides (Core) in PCFN with a particle size of 52 nm (TEM). Surprisingly, PCFN has lower band gap, e-/h+ recombination, and larger charge transfer character than CFN. The decomposition test using MB and MO dyes showed that PCFN degraded 99%, 98%, while CFN degraded only 73% and 54%, respectively, under 50 min sunlight illumination. The reusability was assessed up to 7th cycle for PCFN. The influence of operational parameters (catalyst dose, dye concentration, pH) was tested for PCFN. Further, the antimicrobial action against S. aureus (gram + ve), E. coli (gram -ve) were also tested. The supreme performance of PCFN has been credited to heterostructure dual Z-scheme formation and core-shell morphology supported with PANI, which suppresses the e-/h+ recombination process by promoting their separation. The present finding indicated that the PCFN is a promising modifier for bacterial disinfection and acts as a superb photocatalyst through core-shell formation with PANI support.

Determination of the optimal cut-off value of serum prostate-specific antigen in the prediction of skeletal metastases on technetium-99m whole-body bone scan by receiver operating characteristic curve analysis.

Radionuclide whole-body bone scan is a useful investigation of choice to detect the skeletal metastases in prostate cancer. It is indicated in patients having elevated serum prostate-specific antigen (Sr. PSA) or patients with bone pain. Elevated Sr. PSA levels have high predictive value for skeletal metastases; however, there is no consensus regarding cut-off value of Sr. PSA above which bone scan is indicated. This study was performed to find out the accuracy of Sr. PSA test and to know the optimal cut-off value of Sr. PSA with high sensitivity and specificity in the prediction of skeletal metastases on bone scan in prostate cancer patients. A retrospective analysis of medical records of 307 prostate cancer patients referred to the department of nuclear medicine for bone scan between June 2009 and June 2014 was done. Of 307 patients, 15 cases were excluded due to nonavailability of Sr. PSA. Bone scan was performed 3 h after administration of 20 mCi Tc-99m methylene diphosphonate intravenously. Whole-body sweep imaging was performed and spot views were taken wherever required. Of 292 cases, 174 (59.58%) patients had positive bone scan for metastases and 118 (40.41%) patients had negative bone scan for metastases. Maximum and minimum Sr. PSA levels in positive and negative bone scan patients were 1260 and 0.02 ng/ml and 198.34 ng/ml and 0.01 ng/ml, respectively. On comparison of the mean Sr. PSA levels between positive and negative groups, we found significant Sr. PSA levels (P < 0.05). We used receiver operating characteristic (ROC) curve analyses to find out the accuracy of Sr. PSA test and to know the optimal cut-off value of Sr. PSA with maximum sensitivity and specificity in the prediction of skeletal metastases on bone scan. Area under ROC curve was 0.878 (87%). This indicates that the accuracy of Sr. PSA test in the prediction of skeletal metastases on bone scan was good. The optimal cut-off value of Sr. PSA in the prediction of positive bone scan for skeletal metastases in the management of prostate cancer was 29.16 ng/ml, with sensitivity and specificity of 89.0% and 74.6%, respectively. In this study, we conclude that the accuracy of Sr. PSA test in the prediction of skeletal metastases is good. ROC-derived optimal cut-off value of Sr. PSA for positive skeletal metastases on bone scan is >29.16 ng/ml; thus, the chances of getting positive bone scan for skeletal metastasis are less in prostate cancer patients with Sr. PSA <29.16 ng/ml. ROC-derived sensitivity and specificity of different possible cut-off points of Sr. PSA help reduce the false positive results and increase the diagnostic accuracy of bone scan in the detection of skeletal metastases in prostate cancer patients.

Comparison between peak systolic velocity of the inferior thyroid artery and technetium-99m pertechnetate thyroid uptake in differentiating Graves' disease from thyroiditis

ABSTRACT Objectives The differentiation between the various etiologies of thyrotoxicosis, including those with hyperthyroidism (especially Graves' disease [GD], the most common cause of hyperthyroidism) and without hyperthyroidism (like thyroiditis), is an important step in planning specific therapy. Technetium-99m (99mTc) pertechnetate thyroid scanning is the gold standard in differentiating GD from thyroiditis. However, this technique has limited availability, is contraindicated in pregnancy and lactation, and is not helpful in cases with history of recent exposure to excess iodine. The aim of this study was to identify the diagnostic value of the peak systolic velocity of the inferior thyroid artery (PSV-ITA) assessed by color-flow Doppler ultrasound (CFDU) and compare the sensitivity and specificity of this method versus 99mTc pertechnetate thyroid uptake. Subjects and methods We prospectively analyzed 65 patients (46 with GD and 19 with thyroiditis). All patients were evaluated with clinical history and physical examination and underwent 99mTc pertechnetate scanning and measurement of TRAb levels and PSV-ITA values by CFDU. The diagnosis was based on findings from signs and symptoms, physical examination, and 99mTc pertechnetate uptake. Results Patients with GD had significantly higher mean PSV-ITA values than those with thyroiditis. At a mean PSV-ITA cutoff value of 30 cm/sec, PSV-ITA discriminated GD from thyroiditis with a sensitivity of 91% and specificity of 89%. Conclusion Measurement of PSV-ITA by CFDU is a good diagnostic approach to discriminate between GD and thyroiditis, with sensitivity and specificity values comparable to those of 99mTc pertechnetate thyroid uptake.

Comparison between peak systolic velocity of the inferior thyroid artery and technetium-99m pertechnetate thyroid uptake in differentiating Graves' disease from thyroiditis.

OBJECTIVES: The differentiation between the various etiologies of thyrotoxicosis, including those with hyperthyroidism (especially Graves' disease [GD], the most common cause of hyperthyroidism) and without hyperthyroidism (like thyroiditis), is an important step in planning specific therapy. Technetium-99m (99mTc) pertechnetate thyroid scanning is the gold standard in differentiating GD from thyroiditis. However, this technique has limited availability, is contraindicated in pregnancy and lactation, and is not helpful in cases with history of recent exposure to excess iodine. The aim of this study was to identify the diagnostic value of the peak systolic velocity of the inferior thyroid artery (PSV-ITA) assessed by color-flow Doppler ultrasound (CFDU) and compare the sensitivity and specificity of this method versus 99mTc pertechnetate thyroid uptake. SUBJECTS AND METHODS: We prospectively analyzed 65 patients (46 with GD and 19 with thyroiditis). All patients were evaluated with clinical history and physical examination and underwent 99mTc pertechnetate scanning and measurement of TRAb levels and PSV-ITA values by CFDU. The diagnosis was based on findings from signs and symptoms, physical examination, and 99mTc pertechnetate uptake. RESULTS: Patients with GD had significantly higher mean PSV-ITA values than those with thyroiditis. At a mean PSV-ITA cutoff value of 30 cm/sec, PSV-ITA discriminated GD from thyroiditis with a sensitivity of 91% and specificity of 89%. CONCLUSION: Measurement of PSV-ITA by CFDU is a good diagnostic approach to discriminate between GD and thyroiditis, with sensitivity and specificity values comparable to those of 99mTc pertechnetate thyroid uptake.

Technetium-99m Thyroid Scintigraphy and Human Leukocyte Antigen - B35 in Sub-Acute Thyroiditis.

INTRODUCTION: Sub-acute thyroiditis possibly caused by a viral infection of thyroid gland is associated with a surge in thyroxine levels of the patient. Women in the younger age group are affected more than men. Markedly decreased radioactive iodine thyroid uptakes in a setting of thyrotoxicosis associated with elevated thyroxine levels and reduced thyroid stimulating hormone levels usually clinches the diagnosis. Patients mostly require symptomatic treatment with non-steroidal anti-inflammatory drugs. Sub-acute thyroiditis is a self-limiting disorder with most of the patients making a complete recovery in a span of three to six months. Being geographically and ethnically different the present studies was undertaken with an objective of understanding the clinical, laboratory and thyroid uptake profiles in patients of SAT during its natural history and also find the extent of genetic influences through its association with HLA B35. MATERIALS AND METHODS: 32 patients in the age group of 20-59 years diagnosed to have sub-acute thyroiditis were studied. 18 patients out of 32 were subjected to HLA B35 testing. Other laboratory parameters that included hormonal profile and radioactive thyroid uptakes were performed. RESULTS: Most of the patients were females and in their fourth decade of life. Thyroid stimulating hormone levels were decreased in 32 (100%). A majority of patients had normal anti TPO levels. All the patients had grossly decreased Tc-99m thyroid uptake levels at presentation. HLA B35 test done in 18 patients was reported positive in 10 (55.56%) patients. CONCLUSION: The present study is unique in having used serial Tc-99m thyroid scintigraphy in patients of SAT. A positive HLA B 35 is associated in a majority of patients conferring genetic susceptibility.

Radioactive Iodine-131 as a Definitive Treatment in Rare Association of Down Syndrome With Hyperthyroidism: A Case Report and Review of Literature.

Down syndrome characterized by trisomy of chromosome 21 is frequently associated with thyroid dysfunctions due to underlying autoimmune disorders. Hypothyroidism is the commonest thyroid dysfunction and hyperthyroidism, usually Graves' disease, is far less common. On literature review, we came across approximately 112 cases reported so far with the first such case report in 1946. The published data from India on hyperthyroidism in Down syndrome is of three case reports. We report one such patient, an adult male of 28 years who was administered Iodine-131 as a definitive treatment after 9-10 years of initial diagnosis.

Skeletal Metastases Presenting as Superscan on Technetium 99m Methylene Diphosphonate Whole Body Bone Scintigraphy in Different Type of Cancers: A 5-Year Retro-prospective Study.

The purpose of the study is to find out the overall incidence of superscan among different type of cancers, causes of superscan and its relationship with other parameters such as age, sex, duration of disease, and serum alkaline phosphatase (ALP) levels. This was a retro-prospective study. Records of all previous bone scans and reported patients of superscan were re-evaluated retrospectively. Patients who were diagnosed as having superscan in the preceding 3 years with confirmed histopathological diagnosis were included in the retrospective group. In the prospective group, all the patients who were reported to have superscan appearance over the past 2 years of prospective period were included. Total of 6027 bone scans were examined in a 5-year period and out of which 80 cases were diagnosed as superscan. The overall incidence of superscan in different type of cancers was 1.3% (80/6027). Prostate cancer (46/80) was the most common cause of superscan appearance followed by breast cancer (10/80). Out of 6027 patients referred for bone scan, 307 patients had prostate cancer on histopathological examination. Out of 307 patients with prostate cancer, 46 had superscan appearance. Incidence of superscan in prostate cancer was 14.98% (46/307), and 71.73% (33/46) prostate cancer patients with superscan had Gleason score of 8 and above 8 with mean serum prostate-specific antigen level was 178.42 ng/ml in symptomatic patients and 122 ng/ml in asymptomatic patients. Out of all patients with superscan, 71 patients (88.7%) had elevated serum ALP levels. Overall incidence of superscan in our study was 1.3% in different type of cancer patients, and the most common cause of superscan appearance was prostate cancer. Incidence of superscan appearance in prostatic cancer patients was 14.98%.

Radionuclide Esophageal Transit Scintigraphy in Primary Hypothyroidism.

Background/Aims: Esophageal dysmotility is associated with gastrointestinal dysmotility in various systemic and neuroregulatory disorders. Hypothyroidism has been reported to be associated with impaired motor function in esophagus due to accumulation of glycosaminoglycan hyaluronic acid in its soft tissues, leading to changes in various contraction and relaxation parameters of esophagus, particularly in the lower esophageal sphincter. In this study we evaluated esophageal transit times in patients of primary hypothyroidism using the technique of radionuclide esophageal transit scintigraphy. Methods: Thirty-one patients of primary hypothyroidism and 15 euthyroid healthy controls were evaluated for esophageal transit time using 15-20 MBq of Technetium-99m sulfur colloid diluted in 10-15 mL of drinking water. Time activity curve was generated for each study and esophageal transit time was calculated as time taken for clearance of 90% radioactive bolus from the region of interest encompassing the esophagus. Esophageal transit time of more than 10 seconds was considered as prolonged. Results: Patients of primary hypothyroidism had a significantly increased mean esophageal transit time of 19.35 ± 20.02 seconds in comparison to the mean time of 8.25 ± 1.71 seconds in healthy controls (P < 0.05). Esophageal transit time improved and in some patients even normalized after treatment with thyroxine. A positive correlation (r = 0.39, P < 0.05) albeit weak existed between the serum thyroid stimulating hormone and the observed esophageal transit time. Conclusions: A significant number of patients with primary hypothyroidism may have subclinical esophageal dysmotility with prolonged esophageal transit time which can be reversible by thyroxine treatment. Prolonged esophageal transit time in primary hypothyroidism may correlate with serum thyroid stimulating hormone levels.

Nodular Graves' disease with medullary thyroid cancer.

Co-existence of thyroid nodules with Graves' disease has been reported in various studies. 10-15% of such nodules harbor thyroid cancer with papillary thyroid cancer being the commonest. Medullary thyroid cancer (MTC) in nodules associated with Graves' disease is rare. On literature survey, we came across 11 such cases reported so far. We report a 62-year-old female with Graves' disease who also had a thyroid nodule that on fine-needle aspiration cytology and the subsequent postthyroidectomy histopathological examination was reported to be MTC.

Iodine-131 avid distant metastasis in differentiated thyroid cancer: An initial institutional experience from the northern part of India.

OBJECTIVE: The aim of the study was to study the clinical profile in patients of differentiated thyroid cancer (DTC) with Iodine-131 avid distant metastasis at presentation. The study also attempted to evaluate factors influencing survival among these patients. MATERIAL AND METHODS: The cohort includes 35 patients (26 Female, 9 Male) studied retrospectively and prospectively over a period of 5 years at the Sher-I-Kashmir Institute of Medical Sciences, Srinagar, India. RESULTS: The five years cause specific survival among patients of DTC with distant metastasis in the study group was 74.3%. The mean age at presentation was 41.4 years with female patients outnumbering the male patients in a ratio of 5:1. Papillary histopathology was the commonest in 65.7% followed by Follicular in 31.4% and poorly differentiated cancer in 2.9% of patients.31.4% 0f patients presented with relatively advanced AJC/UICC tumor stage of T3-T4. Bone was the commonest site of metastasis in 42.85% of patients followed by lung in 40% 0f patients. 82.9% of patients had only single organ metastasis. Therapeutic Radioiodine was administered in 31 (88.6%) patients. On univariate analysis of various factors that may be influencing the cause specific survival at 5 years, age ≥ 45 years, T3-T4 tumor stage, regional lymph node metastasis, follicular histopathology and non administration of radioiodine revealed significant (P<0.05) association with a poor 5 year survival. However multivariate analysis identified advanced tumor stage (T3-T4) and non administration of radioiodine to be the only independent factors associated with poor survival. CONCLUSION: Patients of differentiated thyroid cancer with distant metastasis having advanced tumor stage (T3-T4) and those in whom therapeutic radioiodine (I-131) is not administered seem to have an unfavorable prognosis in terms of a 5 years cause specific survival.

Significant association of TP53 Arg72Pro polymorphism in susceptibility to differentiated thyroid cancer.

BACKGROUND: Among various polymorphic variants of TP53 gene, codon 72 polymorphism (Arg72Pro) has been found to be associated with cancer susceptibility, but only few studies have investigated their effect on thyroid cancer risk. OBJECTIVE: A case control study was conducted to elucidate the possible role of this SNP as risk factor in thyroid cancer development and to examine its correlation with various clinicopathological variables. METHODS: In this study, we tested the genotype distribution by PCR-RFLP in 140 thyroid cancer patients and 200 cancer-free controls from Kashmir Valley. RESULTS: Genotype frequencies of Arg/Arg (GG), Arg/Pro (GC), and Pro/Pro (CC) genotypes among cases were 0.286, 0.343 and 0.371 while in controls 0.45, 0.37 and 0.18 respectively. Proline allele frequency was significantly higher than arginine frequency in patient group (OR = 2.06, 95% C.I = 1.5-2.8). Significant association was found between variant genotype of codon 72 of TP53 gene and young age group, female gender, urban dwellers, non-smokers and patients with elevated TSH levels (P < 0.05). CONCLUSION: It is evident from our study that Arg72Pro SNP of TP53 gene is connected with higher susceptibility to thyroid cancer especially in young age group, female gender, non-smokers and patients with elevated TSH levels, hence, implicated in thyroid carcinogenesis.

Comparison of phenobarbitone and ursodeoxycholic acid in drug-augmented hepatobiliary scintigraphy for excluding the diagnosis of obstructive cholestasis in neonatal cholestasis syndrome.

OBJECTIVES: Neonatal cholestasis is a common cause of jaundice among newborns. Hepatobiliary scintigraphy plays an important role in the diagnosis of neonatal cholestasis by ruling out extrahepatic biliary atresia, which is one of the common causes. Phenobarbitone and ursodeoxycholic acid (UDCA) have been used to improve the specificity of hepatobiliary scintigraphy in ruling out obstructive causes of neonatal cholestasis syndrome (NCS). The present study was undertaken to compare the utility of phenobarbitone and UDCA in augmenting hepatobiliary scintigraphy in the evaluation of NCS. MATERIALS AND METHODS: Seventy-four consecutive patients with NCS referred for hepatobiliary scintigraphy were initially subjected to a baseline scan. Twenty patients showed tracer activity in the intestine within 24 h after injection, thus ruling out obstructive cholestasis. Fifty-four patients who did not show any tracer activity in the intestine were categorized as nonexcretors. Four nonexcretors were lost to follow-up and were excluded from the study. Fifty nonexcretors showing scan features suggestive of obstructive cholestasis were further randomized into those receiving phenobarbitone (n=20), UDCA (n=20), or placebo (n=10). These groups were further evaluated with drug-augmented hepatobiliary scintigraphy, after premedication, for any excretory activity in the intestine. RESULTS AND CONCLUSION: Out of 50 patients who were evaluated with drug-augmented hepatobiliary scintigraphy two patients from the phenobarbitone group and one patient each from UDCA and placebo groups showed a change in excretory pattern from the baseline scan. However, these results were statistically nonsignificant (P=1.00). In the present study, drug-augmented (phenobarbitone or UDCA) hepatobiliary scintigraphy did not seem to improve the results (negative predictive value) for ruling out an obstructive cause of neonatal cholestasis.

Possible Impact of RET Polymorphism and Its Haplotypic Association Modulates the Susceptibility to Thyroid Cancer.

Rearranged during Transfection (RET) gene polymorphisms act to influence thyroid cancer in a polygenic and low-penetrance manner and no study regarding RET alterations in thyroid cancer has undergone from this part of the world (North India). We evaluated RET G691S (rs1799939), L769L (rs1800861), and S904S (rs1800863) polymorphisms to elucidate their possible role as risk factors in papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC). Polymorphic analysis of RET gene was performed by polymerase chain reaction (PCR), followed by restriction fragment length polymorphism (RFLP). In RET G691S polymorphism, the overall distribution of variant alleles (GA + AA) in cases was 62.9% as against 44.5% in controls (P < 0.05) whereas frequency of RET L769L variant alleles (TG + GG) in cases was 70% versus 88% in controls (P < 0.05). In RET S904S, frequency of variant alleles (CG + GG) in cases was 56% versus 44% in controls (P < 0.05). Interestingly, G691S/L769L variant showed increased risk for the non-smokers (P < 0.05). RET S904S variant showed association with benign thyroid disease as against those with no history. The over-representation of homozygotes in G691S and L769L polymorphic variants was not observed, which suggest a "Dominant mode of inheritance." The S904S polymorphism heterozygote lies almost in the middle of the two homozygotes confirming an "Additive mode of inheritance." In conclusion, RET gene G691S/S904S polymorphisms were over-represented and L769L polymorphism was under-represented in PTC and FTC patients. RET polymorphic variants could act synergistically in the development or progression of PTC and FTC.