Age‐based life history parameters and status assessments of by‐catch species (Lethrinus borbonicus,Lethrinus microdon,Pomacanthus maculosus and Scolopsis taeniatus) in the southern Arabian Gulf

Life history and demographic parameters for Lethrinus borbonicus, Lethrinus microdon, Pomacanthus maculosus and Scolopsis taeniatus in the southern Arabian Gulf were estimated using a combination of size frequency, biological and size‐at‐age data. Defined structural increments consisting of alternating translucent and opaque bands in transverse sections of sagittal otoliths were validated as annuli. The maximum age estimates ranged from 5 years for Scolopsis taeniatus to 36 years for Pomacanthus maculosus. The size‐at‐age relationships were highly asymptotic in form with the majority of growth being achieved early in life. There were significant differences in the growth characteristics between sexes for Pomacanthus maculosus, with males approaching a larger asymptotic size at a faster rate than females. With the exception of Scolopsis taeniatus, the mean age at which fish became vulnerable to capture was lower than the mean age at first sexual maturity. The stocks of L. microdon, P. maculosus and S. taeniatus were exploited within sustainable limits, conversely, L. borbonicus was found to be overexploited and recruitment overfishing may have occurred as the relative spawner biomass per recruit was below 30% of the unexploited state.     

Carboxylic Acids as Biomarkers of Biomphalaria alexandrina Snails Infected with Schistosoma mansoni

Biomphalaria alexandrina snails play an indispensable role in transmission of schistosomiasis. Infection rates in field populations of snails are routinely determined by cercarial shedding neglecting prepatent snail infections, because of lack of a suitable method for diagnosis. The present study aimed at separation and quantification of oxalic, malic, acetic, pyruvic, and fumaric acids using ion-suppression reversed-phase high performance liquid chromatography (HPLC) to test the potentiality of these acids to be used as diagnostic and therapeutic biomarkers. The assay was done in both hemolymph and digestive gland-gonad complex (DGG) samples in a total of 300 B. alexandrina snails. All of the studied acids in both the hemolymph and tissue samples except for the fumaric acid in hemolymph appeared to be good diagnostic biomarkers as they provide not only a good discrimination between the infected snails from the control but also between the studied stages of infection from each other. The most sensitive discriminating acid was malic acid in hemolymph samples as it showed the highest F-ratio. Using the Z-score, malic acid was found to be a good potential therapeutic biomarker in the prepatency stage, oxalic acid and acetic acid in the stage of patency, and malic acid and acetic acid at 2 weeks after patency. Quantification of carboxylic acids, using HPLC strategy, was fast, easy, and accurate in prediction of infected and uninfected snails and possibly to detect the stage of infection. It seems also useful for detection of the most suitable acids to be used as drug targets.     

Blood sphingolipidomics in healthy humans: impact of sample collection methodology

We used a HPLC-MS/MS methodology for determination of a basic metabolomic profile (18:1,18:0 sphingoid backbone, C₁₄-C₂₆ N-acyl part) of “normal” sphingolipid levels in human serum and plasma. Blood was collected from healthy males and nonpregnant females under fasting and nonfasting conditions with and without anticoagulants. Sphingolipids analyzed included sphingoid bases, sphingosine and dihydrosphingosine, their 1-phosphates (S1P and dhS1P), molecular species (C_n-) of ceramide (Cer), sphingomyelin (SM), hexosylceramide (HexCer), lactosylceramide (LacCer), and Cer 1-phosphate (Cer1P). SM, LacCer, HexCer, Cer, and Cer1P constituted 87.7, 5.8, 3.4, 2.8, and 0.15% of total sphingolipids, respectively. The abundant circulating SM was C₁₆-SM (64.0 µM), and it increased with fasting (100 µM). The abundant LacCer was C₁₆-LacCer (10.0 µM) and the abundant HexCer was C₂₄-HexCer (2.5 µM). The abundant Cer, C₂₄-Cer (4.0 µM), was not influenced by fasting; however, levels of C₁₆-C₂₀ Cers were decreased in response to fasting. S1P levels were higher in serum than plasma (0.68 µM vs. 0.32 µM). We also determined levels of sphingoid bases and SM species in isolated lipoprotein classes. HDL₃ was the major carrier of S1P, dhS1P, and Sph, and LDL was the major carrier of Cer and dhSph. Per particle, VLDL contained the highest levels of SM, Cer, and S1P. HPLC-MS/MS should provide a tool for clinical testing of circulating bioactive sphingolipids in human blood.     

No evidence of altered alveolar macrophage polarization,but reduced expression of TLR2, in bronchoalveolar lavage cells in sarcoidosis

Background

Sarcoidosis is a granulomatous inflammatory disease, possibly of infectious aetiology. We aimed to investigate whether the degree of functional polarization of alveolar macrophages (AMs), or Toll-like receptor (TLR) expression, is associated with sarcoidosis or with distinct clinical manifestations of this disease.

Methods

Total BAL cells (cultured four or 24 h in medium, or stimulated 24 h with LPS) from 14 patients and six healthy subjects, sorted AMs from 22 patients (Löfgren''s syndrome n = 11) and 11 healthy subjects, and sorted CD4+ T cells from 26 patients (Löfgren''s syndrome n = 13) and seven healthy subjects, were included. Using real-time PCR, the relative gene expression of IL-10, IL-12p35, IL-12p40, IL-23p19, CCR2, CCR7, iNOS, CXCL10, CXCL11, CXCL16, CCL18, CCL20, CD80, and CD86, and innate immune receptors TLR2, TLR4, and TLR9, was quantified in sorted AMs, and for selected genes in total BAL cells, while IL-17A was quantified in T cells.

Results

We did not find evidence of a difference with regard to alveolar macrophage M1/M2 polarization between sarcoidosis patients and healthy controls. TLR2 gene expression was significantly lower in sorted AMs from patients, particular in Löfgren''s patients. CCL18 gene expression in AMs was significantly higher in patients compared to controls. Additionally, the IL-17A expression was lower in Löfgren''s patients'' CD4+ T cells.

Conclusions

Overall, there was no evidence for alveolar macrophage polarization in sarcoidosis. However, there was a reduced TLR2 mRNA expression in patients with Löfgren''s syndrome, which may be of relevance for macrophage interactions with a postulated sarcoidosis pathogen, and for the characteristics of the ensuing T cell response.     

Development and Evaluation of Hydrophilic Colloid Matrix of Famotidine Tablets

The objective of the present study was to develop a once-daily sustained-release (SR) matrix tablet of famotidine. Nine different formulations (F1–F9) were prepared by direct compression method using Avicel PH101 as filler/binder in the range of 41–27% in F1–F3, 18–22% in F4–F7, and 16–18% in F8–F9 and hydroxypropyl methylcellulose (4,000 cps) as hydrophilic matrix was used in F1–F3 from 19% to 30%, around 40% in F4–F7, and 42–45% in F8–F9. Talc and Aerosil were added in the ratio of 0.7–1.2%. The tablets were subjected to various physical parameters including weight variation test, hardness, thickness, diameter, friability, and in vitro release studies. Assay was also performed according to the USP 30 NF 25 procedure. The results of the physical parameters and assay were found to be within the acceptable range. In vitro dissolution results indicated that formulation F4–F7, having around 40% of rate control polymer, produced a SR pattern throughout 24 h. F1–F3 showed drug release at a faster rate, while F8–F9 released much slower, i.e., <80% in 24 h. Model-dependent and model-independent methods were used for data analysis and the best results were observed for F4 in zero order (r ² = 0.984) and F6 in Korsmeyer and Higuchi (r ² = 0.992 and 0.988). The parameter n indicated anomalous diffusion, while β in Weibull showed a parabolic curve with higher initial slope. The f ₂ similarity test was performed taking F4 as a reference formulation. Only the F5–F7 formulations were similar to the reference formulation F4. The mean dissolution time was around 10 h for the successful formulation.     

Nanoscale dielectrophoretic spectroscopy of individual immobilized mammalian blood cells

Dielectrophoretic force microscopy (DEPFM) and spectroscopy have been performed on individual intact surface-immobilized mammalian red blood cells. Dielectrophoretic force spectra were obtained in situ in ~125 ms and could be acquired over a region comparable in dimension to the effective diameter of a scanning probe microscopy tip. Good agreement was observed between the measured dielectrophoretic spectra and predictions using a single-shell cell model. In addition to allowing for highly localized dielectric characterization, DEPFM provided a simple means for noncontact imaging of mammalian blood cells under aqueous conditions. These studies demonstrate the feasibility of using DEPFM to monitor localized changes in membrane capacitance in real time with high spatial resolution on immobilized cells, complementing previous studies of mobile whole cells and cell suspensions.     

Role of fine needle aspiration cytology in nodular sclerosis variant of Hodgkin's lymphoma

OBJECTIVE: To assess the efficacy of fine needle aspiration cytology (FNAC) in the diagnosis of nodular sclerosis variant of Hodgkin's lymphoma (NSHL) and to analyze cytologic features that could help in subtyping a case of Hodgkin's lymphoma into this variant. STUDY DESIGN: FNAC smears of 18 histopathologically proven cases of NSHL were analyzed for a variety of features. RESULTS: On initial cytologic assessment, 14 of 18 cases were diagnosed as Hodgkin's lymphoma. No further subtyping was performed. In this retrospective analysis it was possible to revise the diagnosis in the remaining 4 cases. Of the various cytologic features analyzed, presence of numerous lacunar-type cells along with fibroblasts and collagenous material were useful pointers toward a diagnosis of nodular sclerosis variant. Fibroblasts were seen in 83.33%, collagenous material in 27.77% and numerous lacunar cells in 77.77%. CONCLUSION: Subtyping of NSHL based on cytologic features alone has been a matter of debate for a long time. Of the various subtypes, nodular sclerosis poses the greatest diagnostic difficulty. Though certain cytologic features may help in suggesting a diagnosis of nodular sclerosis variant, the primary role of fine needle aspiration is to diagnose a case of Hodgkin's lymphoma as such and advise histopathologic examination for further categorization.     

Structural basis for inhibition of protein-tyrosine phosphatase 1B by isothiazolidinone heterocyclic phosphonate mimetics

Crystal structures of protein-tyrosine phosphatase 1B in complex with compounds bearing a novel isothiazolidinone (IZD) heterocyclic phosphonate mimetic reveal that the heterocycle is highly complementary to the catalytic pocket of the protein. The heterocycle participates in an extensive network of hydrogen bonds with the backbone of the phosphate-binding loop, Phe(182) of the flap, and the side chain of Arg(221). When substituted with a phenol, the small inhibitor induces the closed conformation of the protein and displaces all waters in the catalytic pocket. Saturated IZD-containing peptides are more potent inhibitors than unsaturated analogs because the IZD heterocycle and phenyl ring directly attached to it bind in a nearly orthogonal orientation with respect to each other, a conformation that is close to the energy minimum of the saturated IZD-phenyl moiety. These results explain why the heterocycle is a potent phosphonate mimetic and an ideal starting point for designing small nonpeptidic inhibitors.     

NMR and alanine scan studies of glucose-dependent insulinotropic polypeptide in water

Glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone that stimulates the secretion of insulin after ingestion of food. GIP also promotes the synthesis of fatty acids in adipose tissue. Therefore, it is not surprising that numerous literature reports have shown that GIP is linked to diabetes and obesity-related diseases. In this study, we present the solution structure of GIP in water determined by NMR spectroscopy. The calculated structure is characterized by the presence of an alpha-helical motif between residues Ser(11) and Gln(29). The helical conformation of GIP is further supported by CD spectroscopic studies. Six GIP-(1-42)Ala(1-7) analogues were synthesized by replacing individual N-terminal residues with alanine. Alanine scan studies of these N-terminal residues showed that the GIP-(1-42)Ala(6) was the only analogue to show insulin-secreting activity similar to that of the native GIP. However, when compared with glucose, its insulinotropic ability was reduced. For the first time, these NMR and modeling results contribute to the understanding of the structural requirements for the biological activity of GIP.