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1.
Iran J Pathol ; 18(3): 306-311, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37942193

RESUMO

Background & Objective: p16 is a tumor suppressor gene, loss of which is usually associated with poor epithelial differentiation, resulting in tumor progression, which correlates with aggressive clinical behavior and poor prognosis. CDK 4/6 inhibitors can be used as a therapeutic target in p16 negative cases. Bladder cancer is one of the most prevalent cancers, prognosis of which depends not only upon the histopathological type, grade, and invasiveness but also on many other factors. The purpose of this study was to examine p16 expression in bladder urothelial carcinoma among the people who receive treatment at a tertiary care facility in Chattogram, Bangladesh. Methods: At the Department of Pathology, Chittagong Medical College we did this cross-sectional study from July 2019 to September 2021. The study included fifty-one cases of primary urothelial bladder cancer for histopathological examinations. Immunostaining was done by using a primary antibody against p16. Results: Among the 51 cases, twenty-six cases (51%) showed positive p16 expression. The proportion of patients with high-grade (66.7%) and muscle-invasive (86.4%) tumors were more prone to show p16 negativity. Conclusion: The result of this study shows the high grade and muscle-invasive urothelial bladder cancer is linked to reduction of p16 expression, which may provide additional prognostic information to stratify the high-risk patients and can also guide treatment plans, being a therapeutic target.

2.
Chemosphere ; 297: 134022, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35202672

RESUMO

This study investigates the Covid-19 driven indiscriminate disposal of PPE wastes (mostly face mask and medical wastes) in Chittagong metropolitan area (CMA), Bangladesh. Based on the field monitoring, the mean PPE density (PPE/m2± SD) was calculated to be 0.0226 ± 0.0145, 0.0164 ± 0.0122, and 0.0110 ± 0.00863 for July, August, and September 2021, respectively (during the peak time of Covid-19 in Bangladesh). Moreover, gross information on PPE waste generation in the city was calculated using several parameters such as population density, face mask acceptance rate by urban population, total Covid-19 confirmed cases, quarantined and isolated patients, corresponding medical waste generation rate (kg/bed/day), etc. Moreover, the waste generated due to face mask and other PPEs in the CMA during the whole Covid-19 period (April 4, 2020 to September 5, 2021) were calculated to be 64183.03 and 128695.75 tons, respectively. It has been observed that the negligence of general people, lack of awareness about environmental pollution, and poor municipal waste management practices are the root causes for the contamination of the dwelling environment by PPE wastes. As a result, new challenges have emerged in solid waste management, which necessitates the development of an appropriate waste management strategy. The ultimate policies and strategies may help to achieve the SDG goals 3, 6, 11, 12, 13, and 15, and increase public perception on the use and subsequent disposal of PPEs, especially face masks.


Assuntos
COVID-19 , Resíduos de Serviços de Saúde , Bangladesh/epidemiologia , COVID-19/epidemiologia , Humanos , Equipamento de Proteção Individual , Plásticos , SARS-CoV-2
3.
Sci Rep ; 12(1): 117, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34996919

RESUMO

Graphene: zinc oxide nanocomposite (GN:ZnO NC) platform was tried for the sensitive determination of para-nitrophenol (p-NP) through the electrochemical method. ZnO nanoparticles (NPs) were synthesized by the modified wet-chemical method where in potassium hydroxide and zinc nitrate were used as precursors and starch as a stabilizing agent. A green and facile approach was applied to synthesize GN:ZnO NC in which glucose was employed as a reductant to reduce graphene-oxide to graphene in the presence of ZnO NPs. The synthesized NC was characterized using scanning and high-resolution transmission electron microscopy, energy dispersive x-ray analysis, X-ray diffraction and Raman spectroscopic techniques to examine the crystal phase, crystallinity, morphology, chemical composition and phase structure. GN:ZnO NC layer deposited over the glassy carbon electrode (GCE) was initially probed for its electrochemical performance using the standard 1 mM K3[Fe(CN)6] model complex. GN:ZnO NC modified GCE was monitored based on p-NP concentration. An enhanced current response was observed in 0.1 M phosphate buffer of pH 6.8 for the determination of p-NP in a linear working range of 0.09 × 10-6 to 21.80 × 10-6 M with a lower detection limit of 8.8 × 10-9 M employing square wave adsorptive stripping voltammetric technique at a deposition-potential and deposition-time of - 1.0 V and 300 s, respectively. This electrochemical sensor displayed very high specificity for p-NP with no observed interference from some other possible interfering substances such as 2, 4-di-NP, ortho-NP, and meta-NP. The developed strategy was useful for sensitive detection of p-NP quantity in canals/rivers and ground H2O samples with good recoveries.

4.
Environ Sci Pollut Res Int ; 29(18): 27521-27533, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34981371

RESUMO

The present study focuses on the indiscriminate disposal of personal protective equipment (PPEs) and resulting environmental contamination during the 3rd wave of COVID-19-driven global pandemic in the Chittagong metropolitan area, Bangladesh. Because of the very high rate of infection by the delta variant of this virus, the use of PPEs by the public is increased significantly to protect the ingestion/inhalation of respiratory droplets in the air. However, it is a matter of solicitude that general people throw away the PPEs to the dwelling environment unconsciously. With the increase of inappropriate disposal of PPEs (i.e., mostly the disposable face masks made from plastic microfibers), the possibility of transmission of the virus to the general public cannot be neglected completely. This is because this virus can survive for several days on the inanimate matter like plastics and fibers. At the same time, the result of environmental contamination by microplastic/microfiber has been widespread which eventually creates the worst impact on ecosystems and organisms. The present results may help to increase public perception of the use and subsequent disposal of PPEs, especially the face masks.


Assuntos
COVID-19 , Equipamento de Proteção Individual , Bangladesh/epidemiologia , Ecossistema , Humanos , Pandemias , Plásticos , SARS-CoV-2
5.
Iran J Pathol ; 16(4): 362-369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567184

RESUMO

BACKGROUND & OBJECTIVE: Vascular Endothelial Growth Factor (VEGF) is one of the newer molecular markers that acts as a central mediator of tumor angiogenesis and is essential for tumor growth, progression, and metastasis. So anti-angiogenic drugs can be used as anticancer therapy. Treatments with anti-VEGF (Bevacizumab) therapy have been proved to improve relapse-free survival in many tumors. Urinary bladder tumor has become emerging cancer globally among elderly individuals. So, the identification and development of novel biomarkers for effective treatment of urinary bladder carcinoma is essential. The present study aimed to investigate the immunohistochemical expression of VEGF in urothelial carcinoma of urinary bladder and to assess its association with tumor grade and muscle invasiveness. METHODS: This cross-sectional study was conducted in the Department of Pathology, Chittagong Medical College, Chattogram from September 2018 to August 2020. Fifty-six formalin-fixed paraffin-embedded tissue blocks of urinary bladder carcinoma were prepared for both histopathological and immunohistochemical examination. Each slide was evaluated by at least two pathologists. RESULTS: Weak to strong positive expression of VEGF were observed in 52 cases (92.86%). The proportion of tumors positive for VEGF expression was higher among patients with high grade and non-muscle invasive bladder carcinoma. CONCLUSION: We found that VEGF expression has a significant association with tumor grade and an inverse association with muscle invasion. These findings may be useful for selecting the subset of patients likely to respond to anti-VEGF targeted therapy.

6.
Dalton Trans ; 50(34): 11941-11953, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34378588

RESUMO

Two new copper clusters, {Cu4} and {Cu4Cd6}, with polydentate aminoalcohol ligands, diethanol propanolamine (H3L1) and bis-tris{2-[bis(2-hydroxyethyl)amino]-2-(hydroxymethyl)propane-1,3-diol} (H6L2), have been synthesized under mild conditions and characterized thoroughly by single-crystal X-ray diffraction (XRD), infrared spectroscopy, elemental analysis, powder XRD, magnetic and DFT studies, and absorption and fluorescence spectroscopy. The cluster {Cu4} exhibits a rare tetranuclear copper cubane core whereas {Cu4Cd6} forms an unusual heterometallic cage owing to the introduction of the second metal Cd into the ligand. A hexapodal ligand (H6L2) with N and O donor atoms was chosen deliberately for the construction of a high-nuclearity cluster, i.e., {Cu4Cd6}. Interestingly, both the clusters displayed significant cytotoxicity towards human cervical (HeLa) and lung (A549) cancer cells as evident from the shallow IC50 values [15.6 ± 0.8 µM (HeLa), 18.5 ± 1.9 µM (A549) for {Cu4}, and 11.1 ± 1.5 µM (HeLa), 10.2 ± 1.3 µM (A549) for {Cu4Cd6}] obtained after a 24 h incubation. However, moderate toxicity was observed toward immortalized lung epithelial normal cells (HPL1D) with IC50 values of 32.4 ± 1.2 µM for {Cu4} and 27.6 ± 1.7 µM for {Cu4Cd6}. A cellular apoptotic study using HeLa cells revealed that the {Cu4} cluster triggered apoptosis at both the early and late phases while the {Cu4Cd6} cluster facilitate apoptosis mainly at the late apoptotic stage. A standard 2',7'-dichlorodihydrofluorescein-diacetate (DCFH-DA) test affirms that both the clusters enhanced ROS production inside the cancer cells, responsible for promoting cell apoptosis. The decanuclear {Cu4Cd6} clusters demonstrated better anticancer activity compared to the tetranuclear {Cu4} clusters, indicating the role of high nuclearity and additional Cd metal in the enhanced intracellular production of ROS.

7.
RSC Adv ; 11(28): 16881-16891, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35479719

RESUMO

There is an increasing demand for monitoring environmental pollutants and the control requires new sensing materials with better sensitivity, selectivity and reliability. In this study, a series of Co7 clusters incorporating various flexible polyhydroxyamine ligands are explored, with the first report of thiocyanate recognition triggered by crystal formation using a Co7 crystal (1). For this, we have fortunately synthesized three new mixed metal Co7 clusters with fascinating structural features. The clusters were characterized by spectroscopic and single crystal X-ray diffraction methods and later by DFT calculations. Due to its better emission spectrum, 1 was further utilized for evaluating its sensing ability towards various anions in water. Surprisingly, 1 shows better quenching ability towards the recognition of SCN- with a better binding constant. The luminescence quenching towards SCN- detection was further verified by the single crystal method, HSAB principle (symbiosis) and theoretical calculations such as DFT studies. The SCXRD data clearly suggest that the Co7 (1) can be converted into Co14 (1a) by direct reaction with NaSCN under ambient conditions. Besides the soft/hard acid-base concept (symbiosis), the energies of formation, and Co-NCS and Co-OH2 bond energies (as unravelled by DFT) are responsible for this transformation. Therefore, 1 can be used as a selective and sensitive sensor for the detection of thiocyanate anions based on the fluorescence amplification and quenching method. Further, the designed cluster has also been utilized to detect anions in human blood samples to differentiate a smoker and a non-smoker. It has been concluded that the samples of smokers have a high degree of thiocyanate (∼12 or 9.5 mg L-1) in comparison to those of non-smokers (2-3 mg L-1). Thus, this kind of cluster material has high potentiality in the field of bio-medical science in future endeavours for identification of the extent of thiocyanate content in smokers.

8.
Dalton Trans ; 49(41): 14690-14705, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33064787

RESUMO

In this report, metal organic frameworks (MOFs) are designed and tuned for structural variations in order to induce metal capture which in turn directs dye adsorption properties. The three MOFs, Cu-MOF-2COOH, Ni-MOF-COOH and Cd-MOF, are synthesized by employing 1,3,5-benzenetricarboxylic acid (H3-BTC) as the main ligand and 4,4'-dipyridyl (bipy) as the spacer. The MOFs have been characterized using various spectral techniques and single crystal X-Ray studies. A topological analysis using TOPOS Pro reveals that the MOFs possess varying topologies i.e.hcb, hxl, sql and 2C1. Cu-MOF-2COOH and Ni-MOF-COOH contain two and three uncoordinated carboxylic acid groups, respectively, and in Cd-MOF, all three -COOH groups are utilized in bonding. The dye adsorption properties of the MOFs with free carboxylate group(s) were checked and we found that both MOFs are unable to adsorb any of the dyes significantly. The free carboxylate group(s) in the MOFs inspire us to elaborate their metal capturing properties. In different solvents we checked the metal capturing properties of Cu-MOF-2COOH and Ni-MOF-COOH with different metal salts. Surprisingly, both MOFs show better metal capturing properties towards the hard and highly polarizing Fe3+ ion in aqueous medium. Theoretical studies show that the free carboxylate(s) are involved in binding with metals. The post synthetically modified materials (Fe@Cu-MOF-2COOH and Fe@Ni-MOF-COOH) were further checked for their dye adsorption properties and both the doped MOFs show better adsorption properties towards the MB and MO. Furthermore, three kinetic models were employed to understand the reaction mechanism of adsorption and the pseudo second order kinetic model fits the best in both cases. The uncoordinated carboxylate groups in the channels act as post synthetic modification sites for metal capture and the post synthetically modified material thus formed attracts organic dyes following the HSAB concept. The strong interaction existing between the hard Fe3+ ion and hard donors of the dyes is responsible for the enhanced adsorption.

9.
Bioorg Chem ; 95: 103561, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31935603

RESUMO

The present work describes coordination chemistry and biological evaluation of two novel dinuclear complexes [Co2(HL1)2(H2O)2]·8H2O (1) and [Cu2(L2)2] (2) obtained from the Schiff base ligands, H3L1 and H2L2 (formed in situ). The two complexes are characterized by single crystal X-ray, spectral and variable temperature magnetic and theoretical (DFT/TDDFT) analysis. X-ray analysis confirms both the complexes to be dinuclear with distorted octahedral and square pyramidal geometry around Co(II) and Cu(II) ions, respectively. Magnetic studies reveal presence of moderate ferromagnetic interactions in both the complexes with J = 98 (1) and 32 (2) cm-1. The magnetic interactions are further corroborated by DFT studies. Co(II) complex (1) exhibited enhanced catecholase activity with Kcat = 213.48 h-1, which is attributed to the greater extent of charge contribution on Co2+ as compared to Cu2+ as determined by DFT calculations. Furthermore, both the complexes show potent anticancer activity toward HeLa (cervical) and A549 (lung) cancer cell lines with IC50 = 6-7 µM at 48 h, which ascertains both the complexes as better anticancer drugs than cisplatin. Furthermore, 1 and 2 exhibit apoptosis of HeLa cells by demonstrating nuclear blebbings with shrinking morphology. Hence, the present complexes could be employed as a model for metalloenzymes as well as potential anticancer substituents of cisplatin in future course.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Catecol Oxidase/metabolismo , Cobalto/química , Complexos de Coordenação/farmacologia , Cobre/química , Mimetismo Molecular , Bases de Schiff/química , Linhagem Celular Tumoral , Complexos de Coordenação/química , Cristalografia por Raios X , Teoria da Densidade Funcional , Humanos , Estrutura Molecular , Análise Espectral/métodos
10.
ACS Omega ; 4(4): 7738-7749, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459863

RESUMO

In this work, a series of three copper(II) metal-organic frameworks (MOFs), [Cu(4,4'-DP)Cl] n (1), [Cu(4,4'-DP)0.5Cl] n (2), and [Cu(4,4'-TMDP)Cl] n (3) (4,4'-DP = 4,4'-dipyridyl, 4,4'-TMDP = 4,4'-trimethylenedipyridyl), is designed and synthesized under solvothermal conditions. Crystallographic investigations reveal that 1 and 2 have tetrahedral and 3 has octahedral environment around the Cu(II) ion. By varying the solvent conditions and ligand derivatives, the topology can be interestingly tuned. TOPOS Pro provides topological conclusions that 1 is stabilized by unusual 2D + 2D → 3D polycatenation of layers lying in (110) and (11̅0) planes with dihedral angle of 90° showing altogether fes , hcb , and sql topologies. On the other hand, 2 exhibits a bey (3,4-c net) topology and 3 shows 4-fold interpenetration with the dia topology. The dc measurements for 1-3 performed on polycrystalline samples in a 0.1 T field confirm strong ferromagnetic behaviors for 1 and 2 and moderate antiferromagnetic behavior for 3. To examine the sensing properties of the three MOFs, various hazardous nitroaromatic compounds (NACs) were used as analytes. While 1 is a potent fluorescence sensor for highly sensitive detection of multiple NACs, 2 selectively detects meta-dinitrobenzene (m-DNB) with K SV = 5.73 × 105 M-1 and a remarkably lower limit of detection (LOD) value of 1.23 × 10-7 M. 3 does not show sensing ability toward any NAC probably due to the coordination environment being different from those in 1 and 2. The work demonstrates fine-tuning of the topology and in turn magnetic and sensing properties by changing the reaction conditions.

11.
Cytojournal ; 10: 14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23976895

RESUMO

BACKGROUND: The aim of this study was to find out the extent of high-risk human papillomavirus (hrHPV) type 16/18 infection in the cervical tissue of women with epithelial cell abnormality in Pap smear and to establish an association between hrHPV type 16/18 infection and cytohistomorphology. MATERIALS AND METHODS: A cross-sectional descriptive study was carried out in 1699 patients who went through Pap smear examination. Prevalence of epithelial cell abnormality was calculated. Forty eight of these women underwent routine histopathology and 47 were evaluated for human papillomavirus (HPV) type 16/18 by polymerase chain reaction assay. RESULTS: Total 139 women revealed epithelial cell abnormality. Histopathology showed simple inflammation to malignancy. HPV type 16/18 infection was detected in 40.42% (19/47) of the patients. Individually type 16 and 18 were positive in 7 (14.9%) cases each and dual infection with type 16 and 18 were seen in 5 (10.6%) cases. While cervical intraepithelial neoplasia grade 1 (CIN 1) and < CIN 1 lesions showed 18.75% (3 out of 16) and 35% (7 out of 20) positivity respectively, ≥CIN 2 lesions revealed positivity of 81.82% (9 out of 11). Eighty percent HPV 16/18 positivity was seen in women of < 30 years of age. CONCLUSION: The findings of this study will contribute to HPV 16/18 knowledge in Bangladesh that will be useful in assessing the success of current vaccines with limited type spectra and augmenting cervical cancer screening strategies.

12.
Patholog Res Int ; 2012: 908106, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22792510

RESUMO

Background. The aim of this study is to assess the role of multiparameter analysis of silver (Ag)-stained nucleolar organizer regions (AgNORs) technique on aspiration smears of thyroid swellings to distinguish between benign and malignant lesions. Materials and Methods. Aspiration smears from 166 cases of thyroid swellings were examined. Diagnosis was confirmed by histology in 61 cases. AgNOR staining was done on FNA smears according to silver-staining protocol proposed by the International Committee for AgNOR quantification. Multiparameter analysis of AgNORs such as mAgNOR, pAgNOR, and AgNOR size grade was done on 50-100 cells under oil immersion lens. Results. AgNOR parameter of benign and malignant thyroid lesions was compared and was found to be statistically significant. Out of 157 satisfactory AgNOR stained cases, 148 (94.3%) were benign lesions and 9 (5.7%) cases were malignant lesions. In AgNOR analysis, sensitivity was found to be 83.33%, specificity 100%, PPV 100%, NPV 98.21%, and accuracy was 98.36%. Conclusions. AgNOR analysis in the FNA smears is a simple, sensitive, and cost-effective method for differentiating benign from malignant thyroid swellings.

13.
Trop Biomed ; 28(2): 275-82, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22041746

RESUMO

Scanning electron microscope (SEM) images of dust mites, Suidasia pontifica, is presented to provide an improved visualization of the taxonomic characters of these mites. Suidasia pontifica can easily be identified by its scale-like cuticle, presence of external vertical setae (ve), longer external scapular setae (sce) compared to internal scapular setae (sci) and 3 ventral spines on apex of tarsus I. The differences in morphology of male and female S. pontifica are also discussed.


Assuntos
Pyroglyphidae/ultraestrutura , Estruturas Animais/ultraestrutura , Animais , Feminino , Humanos , Malásia , Masculino , Microscopia Eletrônica de Varredura
14.
Tropical Biomedicine ; : 275-282, 2011.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-630060

RESUMO

Scanning electron microscope (SEM) images of dust mites, Suidasia pontifica, is presented to provide an improved visualization of the taxonomic characters of these mites. Suidasia pontifica can easily be identified by its scale-like cuticle, presence of external vertical setae (ve), longer external scapular setae (sce) compared to internal scapular setae (sci) and 3 ventral spines on apex of tarsus I. The differences in morphology of male and female S. pontifica are also discussed.

15.
Dalton Trans ; 39(19): 4624-30, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20372727

RESUMO

Optically clear glasses of various compositions in the system (100-x)(Li2B4O7)·x(Ba5Li2Ti2Nb8O30) (5 ≤ x ≤ 20, in molar ratio) were fabricated by splat quenching technique. Controlled heat-treatment of the as-quenched glasses at 500 °C for 8 h yielded nanocrystallites embedded in the glass matrix. High Resolution Transmission Electron Microscopy (HRTEM) of these samples established the composition of the nano-crystallites to be that of Ba5Li2Ti2Nb8O30. ¹¹B NMR studies revealed the transformation of BO4 structural units into BO3 units owing to the increase in TiO6 and NbO6 structural units as the composition of Ba5Li2Ti2Nb8O30 increased in the glass. This, in turn, resulted in an increase in the density of the glasses. The influence of the nominal composition of the glasses and glass nanocrystal composites on optical band gap (E(opt)), Urbach energy (ΔE), refractive index (n), molar refraction (R(m)), optical polarizability (α(m)) and third order non-linear optical susceptibility (χ³) were studied.

17.
J Nanosci Nanotechnol ; 9(8): 4910-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19928168

RESUMO

Optically clear glasses of various compositions in the system (100-x) TeO2-x(1.5K2O-Li2O-2.5Nb2O5) (2 < or = x < or = 12, in molar ratio) were prepared by the melt-quenching technique. The glassy nature of the as-quenched samples was established via differential scanning calorimetry (DSC). The amorphous and the crystalline nature of the as-quenched and heat-treated samples were confirmed by the X-ray powder diffraction and transmission electron microscopic (TEM) studies. Transparent glasses comprising potassium lithium niobate (K3Li2Nb5O15) microcrystallites on the surface and nanocrystallites within the glass were obtained by controlled heat-treatment of the as-quenched glasses just above the glass transition temperature (T(g)). The optical transmission spectra of these glasses and glass-crystal composites of various compositions were recorded in the 200-2500 nm wavelength range. Various optical parameters such as optical band gap, Urbach energy, refractive index were determined. Second order optical non-linearity was established in the heat-treated samples by employing the Maker-Fringe method.

19.
J Org Chem ; 67(14): 4957-9, 2002 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-12098311

RESUMO

Refluxing an aldehyde 1 with benzotriazole and benzylcarbamate in the presence of a catalytic amount of p-TsOH gave the corresponding benzyloxycarbonylamino-1-(1-benzotriazolyl)alkane 2 in good yields. Compounds 2 treated with substituted tert-butyl acetates 3 using LDA as a base afford smoothly and under mild conditions the N-2-protected 3-aminoalkanoic esters 4.

20.
Allergy ; 56(3): 262, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11251420
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