Staining Properties Research Articles

Integration of microbiological, epidemiological and next generation sequencing technologies data for the managing of nosocomial infections

At its core, the work of clinical microbiologists consists in the retrieving of a few bytes of information (species identification; metabolic capacities; staining and antigenic properties; antibiotic resistance profiles, etc.) from pathogenic agents. The development of next generation sequencing technologies (NGS), and the possibility to determine the entire genome for bacterial pathogens, fungi and protozoans will likely introduce a breakthrough in the amount of information generated by clinical microbiology laboratories: from bytes to Megabytes of information, for a single isolate. In parallel, the development of novel informatics tools, designed for the management and analysis of the so-called Big Data, offers the possibility to search for patterns in databases collecting genomic and microbiological information on the pathogens, as well as epidemiological data and information on the clinical parameters of the patients. Nosocomial infections and antibiotic resistance will likely represent major challenges for clinical microbiologists, in the next decades. In this paper, we describe how bacterial genomics based on NGS, integrated with novel informatic tools, could contribute to the control of hospital infections and multi-drug resistant pathogens.

Clear cell papulosis: report and review

A 12-month-old boy presented with three months of asymptomatic hypopigmented flat-topped papules on the suprapubic skin and lower abdomen. Emollients and topical steroids offered no improvementand the patient was referred to the dermatology department. Shave biopsy revealed a papillated epidermis with scattered solitary mononuclearclear cells at all levels of the epidermis and an overlying basket weave orthokeratosis. The cells were epithelioid with increased amphophilic cytoplasm. Immunohistochemical staining was positive for CK7,CEA, and CAM5.2 and negative for S100, CD1a, and Mart-1. These findings were consistent with clear cell papulosis. No treatment was recommended as these lesions were asymptomatic. However, yearlyfollow up was recommended given the resemblance of these cells to those of Paget disease. Review of the literature demonstrates a total of 31 biopsy confirmed cases with AE1, CEA, and EMA positivity and S100negativity as the most consistent staining properties. A recent retrospective review of 19 cases documents long term follow-up of at least six years and up to 21 years. The results suggested a tendency toward selfresolution and an absence of malignant progression, supporting the benign nature of these lesions.

Morphology and Chromic Status of Red Blood Cells Are Significantly Influenced by Gestational Diabetes.

BackgroundThe study shows the effect of hyperglycemia on RBCs in terms of morphological changes and their chromic status in women with gestational diabetes mellitus (GDM).MethodsA total of 100 pregnant women were enrolled from Maternity and Children Hospital, Qassim, Saudi Arabia including 40 women with confirmed GDM (group-1), 30 women with either type 1 or type 2 diabetes (group-2) and 30 women with normal pregnancy without GDM or pre-gestational diabetes (control group-3). Demographic, anthropometric, medical and biochemical data were obtained from the study subjects. Complete blood count (CBC) and peripheral smears were performed from routine blood samples. Red blood cells (RBCs) morphological analysis was carried out by a hematologist and deviations in size, shape, and staining properties of the RBCs were recorded.ResultsThe groups were similar in demographic characteristics (P > 0.05). RBCs showed normocytic and normochromic features in 83.3% patients of group-3 as compared to 57.5% in group-1, 30% in group-2, respectively. Microcytic hypochromic cells and anisocytosis were mostly encountered in group-2 in 53.3% and 93.3% patients respectively (P = 0.000). Forty percent of RBCs in goup-1 showed microcytic and hypochromic characteristics as compared to group-3 (P = 0.015). Additionally, 42.5% group-1 patients had anisocytosis as compared to group-3 (P = 0.003). Poikilocytosis, target cells and macrocytes were mostly observed in group-2.ConclusionsPersistent hyperglycemia changes shape, size and hemoglobin contents of RBCs which are associated with the hyperglycemic status and exposure time.

Deplastination: Making plastinates histo-pathologically relevant

IntroductionDeplastination is a process that reverses plastination. While the process is in its infancy, this study was designed to see if deplastinated tissues can be used for histopathological studies. MethodsIn this study, a slice of liver tissue was split into two parts. The first half was processed, sectioned and stained with routine H&E staining while the other half was plastinated with S10 plastination technique and was deplastinated after 3 months using sodium methoxide as the deplastinating agent. It was latter stained with routine H&E. The slides were assessed qualitatively on parameters like tissue and cell identification, staining property, preservation of tissue architecture, visualisation of intracellular structures like nuclei, nucleoli, fat goblets etc. and presence of artefacts due to the process. ResultsIdentification of tissue was possible on the deplastinated slides. Intracellular structures like nuclei, nucleoli, fat droplets were identified in the deplastinated slides. DiscussionIn this study, we have found that sodium methoxide and methanol form good deplastinating agents for small sections of tissue. Identification of endpoint of deplastination forms a crucial step in the process.

UTILIZATION OF EOSIN DYE AS AN ION PAIRING AGENT FOR DETERMINATION OF PHARMACEUTICALS: A BRIEF REVIEW

Globally, dyes are widely used in the pharmaceutical, food, textile, cosmetics, plastics, leather, paint, ink and paper industries. Eosin is an acidic orange-pink dye and has very strong staining properties. Haematoxylin and eosin Y (H&E) combination is the most common staining and primary diagnostic technique in histo-pathological laboratories. This review mainly discussed the utility of eosin dye in quality control laboratories as an ion pairing agent for drug analysis. Eosin Y is one the most common ion pairing agent and its mono and di anionic forms of eosin Y are capable of interacting with many drug molecules to form colored/fluorescent binary or ternary complexes that can be analyzed with or without extraction by spectrofluorimetry and/or spectrophotometry. Quenching fluorescence and advantages of spectrofluorimetry over spectrophotometry were also discussed. Fluorescence detection greatly enhances the sensitivity and providing a sensitive and relatively inexpensive instrumental method of analysis using eosin Y for various important drugs in pure, commercial dosage forms and biological fluids

A Polymer/Peptide Complex-Based Sensor Array That Discriminates Bacteria in Urine.

A negatively charged poly(para-phenyleneethynylene) (PPE) forms electrostatic complexes with four positively charged antimicrobial peptides (AMP). The AMPs partially quench the fluorescence of the PPE and discriminate fourteen different bacteria in water and in human urine by pattern-based fluorescence recognition; the AMP-PPE complexes bind differentially to the components of bacterial surfaces. The bacterial species and strains form clusters according to staining properties (Gram-positive and Gram-negative) or genetic similarity (genus, species, and strain). The identification and data treatment is performed by pattern evaluation with linear discriminant analysis (LDA) of the collected fluorescence intensity data.

A Polymer/Peptide Complex‐Based Sensor Array That Discriminates Bacteria in Urine

AbstractA negatively charged poly(para‐phenyleneethynylene) (PPE) forms electrostatic complexes with four positively charged antimicrobial peptides (AMP). The AMPs partially quench the fluorescence of the PPE and discriminate fourteen different bacteria in water and in human urine by pattern‐based fluorescence recognition; the AMP‐PPE complexes bind differentially to the components of bacterial surfaces. The bacterial species and strains form clusters according to staining properties (Gram‐positive and Gram‐negative) or genetic similarity (genus, species, and strain). The identification and data treatment is performed by pattern evaluation with linear discriminant analysis (LDA) of the collected fluorescence intensity data.

An eye tracking study of bloodstain pattern analysts during pattern classification

Bloodstain pattern analysis (BPA) is the forensic discipline concerned with the classification and interpretation of bloodstains and bloodstain patterns at the crime scene. At present, it is unclear exactly which stain or pattern properties and their associated values are most relevant to analysts when classifying a bloodstain pattern. Eye tracking technology has been widely used to investigate human perception and cognition. Its application to forensics, however, is limited. This is the first study to use eye tracking as a tool for gaining access to the mindset of the bloodstain pattern expert. An eye tracking method was used to follow the gaze of 24 bloodstain pattern analysts during an assigned task of classifying a laboratory-generated test bloodstain pattern. With the aid of an automated image-processing methodology, the properties of selected features of the pattern were quantified leading to the delineation of areas of interest (AOIs). Eye tracking data were collected for each AOI and combined with verbal statements made by analysts after the classification task to determine the critical range of values for relevant diagnostic features. Eye-tracking data indicated that there were four main regions of the pattern that analysts were most interested in. Within each region, individual elements or groups of elements that exhibited features associated with directionality, size, colour and shape appeared to capture the most interest of analysts during the classification task. The study showed that the eye movements of trained bloodstain pattern experts and their verbal descriptions of a pattern were well correlated.

PD-L1 immunohistochemistry in clinical diagnostics of lung cancer: inter-pathologist variability is higher than assay variability

Assessment of programmed cell death ligand 1 (PD-L1) immunohistochemical staining is used for decision on treatment with programmed cell death 1 and PD-L1 checkpoint inhibitors in lung adenocarcinomas and squamous cell carcinomas. This study aimed to compare the staining properties of tumor cells between the antibody clones 28-8, 22C3, SP142, and SP263 and investigate interrater variation between pathologists to see if these stainings can be safely evaluated in the clinical setting. Using consecutive sections from a tissue microarray with tumor tissue from 55 resected lung cancer cases, staining with five PD-L1 assays (28-8 from two different vendors, 22C3, SP142, and SP263) was performed. Seven pathologists individually evaluated the percentage of positive tumor cells, scoring each sample applying cutoff levels used in clinical studies: <1% positive tumor cells (score 0), 1–4% (score 1), 5–9% (score 2), 10–24% (score 3), 25–49% (score 4), and >50% positive tumor cells (score 5). Pairwise analysis of antibody clones showed weighted kappa values in the range of 0.45–0.91 with the highest values for comparisons with 22C3 and 28-8 and the lowest involving SP142. Excluding SP142 resulted in kappa 0.75–0.91. Weighted kappa for interobserver variation between pathologists was 0.71–0.96. Up to 20% of the cases were differently classified as positive or negative by any pathologist compared with consensus score using ≥1% positive tumor cells as cutoff. A significantly better agreement between pathologists was seen using ≥50% as cutoff (0–5% of cases). In conclusion, the concordance between the PD-L1 antibodies 22C3, 28-8 and SP263 is relatively good when evaluating lung cancers and suggests that any one of these assays may be sufficient as basis for decision on treatment with nivolumab, pembrolizumab, and durvalumab. The scoring of the pathologist presents an intrinsic source of error that should be considered especially at low PD-L1 scores.

A novel panel of α-synuclein antibodies reveal distinctive staining profiles in synucleinopathies.

Synucleinopathies are a spectrum of neurodegenerative diseases characterized by the intracellular deposition of the protein α-synuclein leading to multiple outcomes, including dementia and Parkinsonism. Recent findings support the notion that across the spectrum of synucleinopathies there exist diverse but specific biochemical modifications and/or structural conformations of α-synuclein, which would give rise to protein strain specific prion-like intercellular transmission, a proposed model that could explain synucleinopathies disease progression. Herein, we characterized a panel of antibodies with epitopes within both the C- and N- termini of α-synuclein. A comprehensive analysis of human pathological tissue and mouse models of synucleinopathy with these antibodies support the notion that α-synuclein exists in distinct modified forms and/or structural variants. Furthermore, these well-characterized and specific tools allow the investigation of biochemical changes associated with α-synuclein inclusion formation. We have identified several antibodies of interest with diverse staining and epitope properties that will prove useful in future investigations of strain specific disease progression and the development of targeted immunotherapeutic approaches to synucleinopathies.

The haemocytes of the colonial aplousobranch ascidian Diplosoma listerianum: Structural, cytochemical and functional analyses

Diplosoma listerianum is a colonial aplousobranch ascidian of the family Didemnidae that is native to the northeast Atlantic and exhibits a cosmopolitan distribution in temperate waters. It lacks a shared colonial circulation crossing the tunic, and the zooids are connected only by the common tunic. In the present study, the haemocytes of this ascidian were analysed via light and electron microscopy. Their phagocytic and enzymatic activities, staining and immunostaining properties, and lectin affinity were examined with various classical methods reconsidered and modified for small marine invertebrates. Eight morphotypes were identified in reference to corresponding cell types described in other ascidians: undifferentiated cells (haemoblasts), storage cells for nitrogenous catabolites (nephrocytes) and immunocytes. The immunocytes are involved in immune responses, acting as (1) phagocytes, rich in hydrolases and involved in the clearance of both foreign particles and effete cells (hyaline amoebocytes and macrophage-like cells); (2) cytotoxic cells, able to degranulate and induce cytotoxicity through the release of the enzyme phenoloxidase after an immune stimulus (granular amoebocytes and morula cells); and (3) basophilic cells with an affinity for ConA and NPA that contain heparin and histamine and that show sensitivity to the compound 48/80, promoting their degranulation (mast cell-like granulocytes). In addition, a particular cell type showing exceptional development of the Golgi apparatus and large vacuoles containing a filamentous material has been recognised (spherule cell), for which a role in tunic repair and fibrogenesis has been hypothesised.

Pentamethine cyanine located in mitochondria: relationship between photostability and excited state lifetime

Pentamethine dyes are often used for near infrared fluorescent probes owing to the advantage of high sensitivity, however, their photostability is not so satisfying. In this paper, a series of pentamethine dyes which contain electron-donating groups like amino or hydroxyl groups were synthesized, and the effect of substituents on photostability and the application in cell imaging were also discussed. The results indicated that the photostability of fluorescent dyes which possess electron donors of amino and hydroxyl groups was high, and the lifetime of excited state of fluorescent probes were reduced after leading into the amino group proved by femtosecond transient absorption, respectively. Photostability is negatively correlated with the lifetime of the excited state and the fluorescent dyes are mainly localized in mitochondria of living cells. This research will be of importance for designing cyanine dyes with high photostability and good cellular stain properties.

Age-related changes in immunoreactivity for dopamine β-hydroxylase in carotid body glomus cells in spontaneously hypertensive rats.

The purpose of this study was to investigate immunoreactivity for dopamine β-hydroxylase (DBH) and tyrosine hydroxylase (TH) in carotid body (CB) glomus cells in spontaneously hypertensive rats (SHR/Izm) at 4 (prehypertensive stage), 8 (early stage of developmental hypertension), 12 (later stage of developmental hypertension), and 16weeks of age (established hypertensive stage). Age-matched Wistar Kyoto rats (WKY/Izm) were used as controls. Staining properties for TH were similar between both strains at each age. Regarding DBH immunostaining, although some glomus cells showed intense DBH immunoreactivity at 4weeks of age, these cells were rarely observed at 8, 12, and 16weeks of age in WKY/Izm. In SHR/Izm, intense DBH immunoreactivity was observed in some glomus cells at 4weeks of age, these cells were also observed at 8 and 12weeks of age, and their number increased at 16weeks of age. An image analysis showed that the percentage of DBH-immunopositive glomus cells in WKY/Izm was approximately 30% at 4weeks of age and significantly decreased to approximately 10% at 8, 12, and 16weeks of age (p<0.05). This percentage in SHR/Izm was approximately 40% at each age. The gray scale intensity for DBH immunoreactivity in DBH-immunopositive glomus cells was similar in both strains at 4weeks of age, but became significantly lower in WKY/Izm and higher in SHR/Izm with increase in age (p<0.05). These results suggest that noradrenaline in glomus cells plays an important role in the regulation of neurotransmission between CB and afferent nerves during developmental hypertension.

Abstract P6-09-25: Circulating tumor cell clusters-associated gene plakoglobin is a novel prognostic predictor in patients with breast cancer

Abstract Background: Accumulating evidence shows that circulating tumor cells (CTC) are linked to metastatic relapse and are regarded as a prognostic marker for human cancer. It was reported that CTC clusters (CTCc) have more metastatic potential than single CTC. Lately, studies also show that the high expression of plakoglobin, a cell adhesion protein, within the primary tumor are positively associated with CTCc in breast cancer patients. In addition, it is thought that insufficient expression of plakoglobin could promote epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between plakoglobin expression and survival of breast cancer. Materials and Methods:A total of 126 patients with resectable early-stage breast cancer were treated with neoadjuvant chemotherapy (NAC). All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. The expression of plakoglobin were identified by immunohistochemical staining properties in cell membrane. Staining with plakoglobin (clone 4C12) was scored according to the percentage of cells that stained positively: low, 0-25%; medium, 26-75%; high, &amp;gt;75%. We investigated the correlation between the plakoglobin expression in primary tumor specimen and clinical outcomes including overall-survival (OS), disease-free-survival (DFS), distant-metastasis-free-survival (DMFS), the efficacy of NAC. And we examined the relation between the expression of plakoglobin and E-cadherin, EMT marker. Results: The patient with high plakoglobin expression had significantly worse OS (p=0.021, log-rank) and DFS (p=0.015, log-rank), DMFS (p=0.040, log-rank). And the plakoglobin expression had no correlation with pathological complete response (pCR) rate (p=0.596). Also, there was not a statistically significant relationship between the plakoglobin expression and other clinicopathological parameters including tumor size (p=0.708), lymph node status (p=0.479), subtype (p=0.413), nuclear grade (p=0.642), Ki67 (p=0.202), tumor infiltrating lymphocytes (p=0.828). On univariate analysis with respect to distal metastasis, high plakoglobin expression showed worse prognosis than low plakoglobin expression (p=0.013, hazard ratio=4.221). And multivariate analysis found the same result (p=0.015, hazard ratio=4.070). In addition, there was a significant relationship between the expression of plakoglobin and E-cadherin (p=0.023). Conclusions: Plakoglobin expression is an independent prognostic factor in the patients with breast cancer; particularly for DMFS, and this mechanism related to EMT.Background: Accumulating evidence shows that circulating tumor cells (CTC) are linked to metastatic relapse and are regarded as a prognostic marker for human cancer. It was reported that CTC clusters (CTCc) have more metastatic potential than single CTC. Lately, studies also show that the high expression of plakoglobin, a cell adhesion protein, within the primary tumor are positively associated with CTCc in breast cancer patients. In addition, it is thought that insufficient expression of plakoglobin could promote epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between plakoglobin expression and survival of breast cancer. Materials and Methods:A total of 126 patients with resectable early-stage breast cancer were treated with neoadjuvant chemotherapy (NAC). All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. The expression of plakoglobin were identified by immunohistochemical staining properties in cell membrane. Staining with plakoglobin (clone 4C12) was scored according to the percentage of cells that stained positively: low, 0-25%; medium, 26-75%; high, &amp;gt;75%. We investigated the correlation between the plakoglobin expression in primary tumor specimen and clinical outcomes including overall-survival (OS), disease-free-survival (DFS), distant-metastasis-free-survival (DMFS), the efficacy of NAC. And we examined the relation between the expression of plakoglobin and E-cadherin, EMT marker. Results: The patient with high plakoglobin expression had significantly worse OS (p=0.021, log-rank) and DFS (p=0.015, log-rank), DMFS (p=0.040, log-rank). And the plakoglobin expression had no correlation with pathological complete response (pCR) rate (p=0.596). Also, there was not a statistically significant relationship between the plakoglobin expression and other clinicopathological parameters including tumor size (p=0.708), lymph node status (p=0.479), subtype (p=0.413), nuclear grade (p=0.642), Ki67 (p=0.202), tumor infiltrating lymphocytes (p=0.828). On univariate analysis with respect to distal metastasis, high plakoglobin expression showed worse prognosis than low plakoglobin expression (p=0.013, hazard ratio=4.221). And multivariate analysis found the same result (p=0.015, hazard ratio=4.070). In addition, there was a significant relationship between the expression of plakoglobin and E-cadherin (p=0.023). Conclusions: Plakoglobin expression is an independent prognostic factor in the patients with breast cancer; particularly for DMFS, and this mechanism related to EMT. Citation Format: Goto W, Kashiwagi S, Asano Y, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Circulating tumor cell clusters-associated gene plakoglobin is a novel prognostic predictor in patients with breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-25.

MOLECULAR DETECTION AND ANTIBIOGRAM OF SHIGA TOXIN PRODUCING ESCHERICHIA COLI (STEC) ISOLATED FROM DIARRHEIC CHILDREN

This study was designed to determine the shiga toxin producing genes and to investigate antibiotic sensitivity or resistant patterns of the Escherichia coli isolated from diarrheic children at Mymensingh Medical College Hospital, Bangladesh. A total of 83 stool samples were collected and screened for the detection of E. coli on the basis of cultural, staining and biochemical properties followed by molecular detection by Polymerase Chain Reaction (PCR) using genus specific 16SrRNA primers. Antimicrobial susceptibility pattern of E. coli was determined by disc diffusion method against 9 antimicrobial agents. In this study, 27 (32.53%) out of 83 samples, were confirmed as E. coli. Overall prevalence of shiga toxin producing E. coli (STEC) among the examined children was 1.20% (n=1/83). Further, 27 E. coli isolates were analyzed for the presence of Stx-1 and Stx-2 genes by duplex-PCR. The STEC isolate was confirmed to be positive for the presence of the Stx-2 gene only. Highest susceptibility of the E. coli isolates was found against Gentamicin (92.59%), followed by Ciprofloxacin (48.14%) and Moxifloxacin (33.33%). More than 77.78% of the isolates were resistant to more than three antibiotics thus defined as multi-drug resistant (MDR). In conclusion, Gentamicin and Ciprofloxacin can be recommended as the effective drugs successful treatment of STEC infections in children.

Two types of deposits, hyaline droplets and eosinophilic bodies, associated with α2u-globulin accumulation in the rat kidney.

Alpha2u-globulin is an adult male rat-specific protein that accumulates spontaneously or inductively in the renal proximal tubular epithelium and forms microscopically observable deposits, which are generally referred to as “hyaline droplets,” whereas a specific type of deposits is referred to as “eosinophilic bodies” by Japanese toxicologic pathologists. We compared hyaline droplets and eosinophilic bodies using special stains including immunostaining for α2u-globulin and lysosome-associated membrane protein in spontaneously occurring and d-limonene-induced cases. Eosinophilic bodies appeared simultaneously and increased in parallel with the hyaline droplets in the induced case. In both of the spontaneous and induced cases, hyaline droplets and eosinophilic bodies were associated with α2u-globulin and lysosomes, although there were differences in the forms and staining properties that probably reflected the purity or density of α2u-globulin. According to the results, it is not necessary for eosinophilic bodies to be strictly distinguished from hyaline droplets, and it is reasonable to identify eosinophilic bodies as hyaline droplets in α2u-globulin nephropathy in routine toxicity studies, as they have been recognized to be a sequence of changes associated with accumulation of α2u-globulin.

Primary Calcitonin-negative Neuroendocrine Tumor

ABSTRACT Introduction Neuroendocrine tumors (NETs) of the thyroid are rare tumors. Medullary thyroid carcinoma (MTC) is an exact NET of the thyroid gland, arising from the parafollicular cells (C cells). It has unique features like immunohistochemically and biochemically calcitonin positivity and amyloid deposits. In this case report, a rare thyroid tumor is presented, which has neuroendocrine staining properties and does not produce serum or cytoplasmic calcitonin. Case report The patient was a 45-year-old woman who underwent total thyroidectomy because of the countless multiple thyroid nodules and a suspicion about a nodule at the right lobe. On histopathological examination, there was a tumor in the left thyroid lobe that measured 0.4 cm. Tumor immunohistochemical staining was positive for synaptophysin, chromogranin A (neuroendocrine cell markers), and thyroglobulin (Tg), and thyroid transcription factor-1 (TTF-1; follicular cell markers). The staining was negative for calcitonin. Conclusion There are thyroid tumors that are calcitonin-negative and Tg-positive called calcitonin-negative NETs. Careful interpretation and distinction between MTCs are needed at these tumors because they may have different biologic behaviors, and calcitonin negativity makes follow-up of patients challenging. How to cite this article Özden S, Colak A, Saylam B, Cengiz Ö. Primary Calcitonin-negative Neuroendocrine Tumor. World J Endoc Surg 2017;9(3):104-108.

Protein Staining Agents from Cationic and Neutral Luminescent Iridium(III) Complexes.

Seven luminescent iridium(III) complexes were prepared to investigate the relationships between chemical structures and properties of protein staining. For the first time, the effect of the main ligand, the π conjugation effect of the ancillary ligand, and the charge effect of organometallic complexes on protein staining has been revealed. Most importantly, this study gives the first experimental evidence of the potential applications of charge-neutral organometallic complexes in protein staining, which could open an avenue of exploiting novel protein staining agents in the future.

Toward a new avenue in ruthenium-sulphur chemistry of binuclear μ-sulphido bridged (μ-S)2 complexes having Ru2S2 core: Targeted synthesis, crystal structure, biomolecules interaction and their in vitro anticancer activities

A series of hybrid thiosemicarbazone derivatives (H2L1–3) were synthesized by the reactions of diacetyl-2-(4-methyl-3-thiosemicarbazone) with hydrazine derivatives such as 2-hydrazinoquinoline, 2-hydrazinobenzothiazole and 6-hydrazinonicotinic acid arm. The resulting hybrid diacetyl-2-(4-methyl-3-thiosemicarbazonato-hydrazine derivatives were successfully employed as tetradentate ligands to react with [RuHClCO(PPh3)3]. The reactions have led to the binuclear organo-ruthenium(II) complexes of the core type [Ru2(Ln)2(CO)2(μ-S)2], (n=1–3) in which the ruthenium(II) ion bridged by sulphur atoms (μ-S)2. In the new complexes, the ligand charge and stoichiometry proportions could be controlled by the addition of base. All the compounds have been characterized by IR, UV–vis, ESI-MS, (1H, 13C) NMR spectra and elemental analyses. The crystal structure of complexes 1, 2 has been determined by X-ray crystallography, which confirmed the coordination mode of the ligands and revealed a distorted octahedral geometry around the ruthenium ion. Natural bond orbital calculations of complexes 1 and 2 showed that the majority of the electron density of donors tends to the ruthenium ion, since the calculated Mulliken charge for the ruthenium ion is much lesser than the formal value. The binding mode of these complexes with biomolecules such as calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) protein have been investigated by diverse spectrophotometric methods and the results revealed an intercalative mode of interaction. Furthermore, the bio-catalytic efficiencies such as catecholase and phosphatase like activities of ruthenium complexes exhibited high rate (kcat) constant. Furthermore, the complexes (1–3) displayed more cytotoxicity against anticancer cell lines such as MCF-7 (breast), A549 (lung), and HepG2 (liver) than normal Vero cell line. The less cytotoxic activity towards normal cell lines showed that they affect only cancer cell lines. The antiproliferative efficacy of complexes (1–3) has also been analyzed using morphological staining properties (AO/EB, DAPI) by fluorescence microscopy visualization.

Molecular detection of Pasteurella multocida Type B causing haemorrhagic septicemia in cattle and buffaloes of Bangladesh

Hemorrhagic septicemia (HS) is an acute septicemic disease that primarily affects cattle and buffaloes. The disease is caused by Pasteurella multocida sero types B:2 and E:2. The objective of this study was to isolate P. multocida from clinical cases and to confirm its identity using polymerase chain reaction (PCR) based approach. Clinical samples of two suspected cases of haemorrhagic septicemia of cattle and buffalo from Mymensingh and Rajshahi districts respectively were collected. Two isolates were isolated from these suspected cases and primarily identified as P. multocida based on morphological study, staining properties, and cultural and biochemical characteristics. The isolates were confirmed initially as P. multocida at genus level by PCR using genus specific primers. Later, the isolates were confirmed as P. multocida type B, the causal agent of haemorrhagic septicemia, by PCR with primers specific for P. multocida type B. These isolated organisms can be used as vaccine candidate for the production of effective vaccine against haemorrhagic septicemia.Progressive Agriculture 27 (2): 175-179, 2016