Differential Expression of Vitreous Proteins in Young and Mature New Zealand White Rabbits

Different anatomical regions have been defined in the vitreous humor including central vitreous, basal vitreous, vitreous cortex, vitreoretinal interface and zonule. In this study we sought to characterize changes in the proteome of vitreous humor (VH) related to compartments or age in New Zealand white rabbits (NZW). Vitreous humor was cryo-collected from young and mature New Zealand white rabbit eyes, and dissected into anterior and posterior compartments. All samples were divided into 4 groups: Young Anterior (YA), Young Posterior (YP), Mature Anterior (MA) and Mature Posterior (MP) vitreous. Tryptic digests of total proteins were analyzed by liquid chromatography followed by tandem mass spectrometry. Spectral count was used to determine the relative protein abundances and identify proteins with statistical differences between compartment and age groups. Western blotting was performed to validate some of the differentially expressed proteins. Our results showed that 231, 375, 273 and 353 proteins were identified in the YA, YP, MA and MP respectively. Fifteen proteins were significantly differentially expressed between YA and YP, and 11 between MA and MP. Carbonic anhydrase III, lambda crystallin, alpha crystallin A and B, beta crystallin B1 and B2 were more abundant in the anterior region, whereas vimentin was less abundant in the anterior region. For comparisons between age groups, 4 proteins were differentially expressed in both YA relative to MA and YP relative to MP. Western blotting confirmed the differential expression of carbonic anhydrase III, alpha crystallin B and beta crystallin B2. The protein profiles of the vitreous humor showed age- and compartment-related differences. This differential protein profile provides a baseline for understanding the vitreous compartmentalization in the rabbit and suggests that further studies profiling proteins in different compartments of the vitreous in other species may be warranted.     

Steroid synthesis and metabolism in the nervous system: Trophic and protective effects

Steroids influence the activity and plasticity of neurons and glial cells during early development, and they continue to exert trophic and protective effects in the adult nervous system. Steroids are produced by the gonads and adrenal glands and reach the brain, the spinal cord and the peripheral nerves via the bloodstream. However, some of them, named “neurosteroids”, can also be synthesized within the nervous system. They include pregnenolone, progesterone, dehydroepiandrosterone and their reduced metabolites and sulfate esters. Little is known concerning the regulation of steroid synthesis in the nervous system, which involves interactions between different cell types. For example, the synthesis of progesterone by Schwann cells in peripheral nerves is regulated by a diffusible neuronal signal. Neurotrophic and neuroprotective effects of steroids have been documented both in cell culture and in vivo. PROG plays an important role in the neurological recovery from traumatic injury of the brain and spinal cord by mechanisms involving protection from excitotoxic cell death, lipid peroxydation and the induction of specific enzymes. After transection of the rat spinal cord, PROG increases the number of nitric oxide synthase expressing astrocytes immediately above and below the lesion. PROG also plays an important role in the formation of new myelin sheaths. This has been shown in the regenerating mouse sciatic nerve after lesion and in cocultures of sensory neurons and Schwann cells. PROG promotes myelination by activating the expression of genes coding for myelin proteins. The modulation of neurostransmitter receptors, in particular the type A γ-aminobutyric acid, the N-methyl-D-aspartate and the sigma 1 receptors, is involved in the psychopharmacological effects of steroids and allows to explain their anticonvulsant, anxiolytic, antidepressive and sedative effects as well as their influence on memory. Pregnenolone sulfate has been shown to reverse age-related deficits in spatial memory performance and to have protective effects on memory in different models of amnesia.     

Immune response of Anopheles gambiae to the early sporogonic stages of the human malaria parasite Plasmodium falciparum

Deciphering molecular interactions between the malaria parasite and its mosquito vector is an emerging area of research that will be greatly facilitated by the recent sequencing of the genomes of Anopheles gambiae mosquito and of various Plasmodium species. So far, most such studies have focused on Plasmodium berghei, a parasite species that infects rodents and is more amenable to studies. Here, we analysed the expression pattern of nine An.gambiae genes involved in immune surveillance during development of the human malaria parasite P.falciparum in mosquitoes fed on parasite-containing blood from patients in Cameroon. We found that P.falciparum ingestion triggers a midgut-associated, as well as a systemic, response in the mosquito, with three genes, NOS, defensin and GNBP, being regulated by ingestion of gametocytes, the infectious stage of the parasite. Surprisingly, we found a different pattern of expression of these genes in the An.gambiae-P.berghei model. Therefore, differences in mosquito reaction against various Plasmodium species may exist, which stresses the need to validate the main conclusions suggested by the P.berghei-An.gambiae model in the P.falciparum-An.gambiae system.     

Symptomatic hypopituitarism revealing primary suprasellar lymphoma

Background

Cause-specific mortality is a commonly used endpoint of clinical trials or prospective studies. However, it is sometimes difficult for physician to determine the underlying-cause-of-death (UCD), especially for diabetic patients coexisted with cardiovascular diseases (CVD). The aim of this survey was to examine whether internists with different specialties have different opinions on the reporting of diabetes as the UCD.

Methods

A total of 549 physicians completed the questionnaire in Taiwan, which comprised seven hypothetical case scenarios, each indicating a different level of contribution of diabetes in initiating the chain of events leading to death.

Results

As a whole, endocrinologists were more likely than cardiologists and nephrologists to report diabetes as the UCD. The differences were more prominent when the diabetic patient had a coexisting CVD. In scenario 3 (a diabetic patient with hypertension who died from acute myocardial infarction), the percentage was 56% in endocrinologists, which was significantly higher than in cardiologists (42%) and nephrologists (41%). In scenario 4 (a diabetic patient with hypertension who died from cerebrovascular infarction), the percentage was 45% in endocrinologists, and only 31% in cardiologists and 36% in nephrologists.

Conclusions

Internists of different sub-specialties do have different opinions on the reporting of diabetes as the UCD, especially when the diabetic patient has a coexisting CVD.     

Occurrence of <Emphasis Type="Italic">Vibrio cholerae</Emphasis> non-O1 in three wastewater treatment plants in Agadir (Morocco)

A total of 21 isolates of Vibrio cholerae non-O1 strains were isolated from three wastewater treatment plants in Agadir, Morocco. The isolates were analyzed by biochemical analysis, antibiogram, pulsed-field gel electrophoresis and the MALDI-TOF patterns of their protein masses were compared. Over 67% of isolates were susceptible to antimicrobial agents tested and 14% proved resistant to both trimethoprim-sulfamethoxazole and nalidixic acid. Typing by pulsed-field gel electrophoresis with NotI digestion revealed that the V. cholerae non-O1 strains from Agadir (Morocco) have a lower level of genetic homogeneity, the restriction patterns of whole-chromosomal DNA grouped the V. cholerae O1 and V. alginolyticus strains into a separate cluster from V. metschnikovii and V. cholerae non-O1 isolates. Furthermore, to gain additional analytical accuracy and reliability in the analysis we used dendrogram based on MALDI-TOF spectral patterns generated by the BioTyper 1.1™ software. All m/z signatures of all strains tested indicate that the mass spectral data contained sufficient information to distinguish between strains of V. cholerae.     

Synthesis and Biological Evaluations of Click-Generated Nitrogen Mustards

This paper describes the synthesis of new click-generated nitrogen mustards and their biological evaluation. By using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, we managed to synthesize eight new nitrogen mustards. This strategy paves the way for the synthesis of a new family of nitrogen mustard, with an important structural variability. Furthermore, we studied the biological activity of synthesized compounds by testing their cytotoxicity on four representative cancer cell lines A431, JURKAT, K562, and U266. One structure, 1-benzyl-4-(N,N-di-2-chloroethylaminomethyl)-1H-[1 Noll, D.M.; McG.Mason, T.; Miller, P.S. Formation and repair of interstrand cross-links in DNA. Chem. Rev. 2006, 106, 277–301.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar],2 Rink, S.M.; Hopkins, P.B. Direct evidence for DNA intrastrand cross-linking by the nitrogen mustard mechlorethamine in synthetic oligonucleotides. Bioorg. Med. Chem. Lett. 1995, 5(23), 2845–2850.[Crossref], [Web of Science ®] , [Google Scholar],3 Chabner, B.A.; Collins, J.M. Cancer Chemotherapy: Principles and Practices, PA, J.B. Lippincott Company, Philadelphia, 1990, pp. 276–313. [Google Scholar]]triazole, showed an interesting cytotoxic effect.     

Somatic embryogenesis in cell suspension cultures of olive <Emphasis Type="Italic">Olea europaea</Emphasis> (L.) ‘Chetoui’

Somatic embryogenesis of olive Olea europaea (L.) ‘Chetoui’ was studied using cell suspension cultures initiated from mature leaf-derived calli. Calli were developed on half-strength MS medium supplemented with 10 μM NAA and 2.25 μM 2i-P in the dark. Different combinations of three plant growth regulators (2,4-D, NAA and zeatin) were tested to determine cell proliferation and somatic embryogenesis induction and differentiation. Embryogenic suspension cultures were established in olive-modified medium for embryogenesis (OMe) containing 2.5 μM 2,4-D and 2.5 μM zeatin. Pre-globular and globular embryos were induced from mature olive tissue in liquid medium. In addition, the nitrogen form as inorganic (reduced; (NH₄)₂SO₄ or oxidized; KNO₃) and organic (CH) was used separately or in combination to improve the cell growth and proliferation. The most effective growth rate and cell proliferation were obtained with the medium containing inorganic and organic nitrogen forms.     

3-Substituted Pyrazinone Nucleosides—A New Family of D4T Analogues

The synthesis of a new family of D4T analogues is described to study the influence of pyrazinone base on antiretroviral power. Substitution of 3H by methyl or n-decyl increases the lipophilic character and may facilitate diffusion across cell membranes. The compounds were characterized by ¹H NMR and infrared spectroscopy. Antiviral (HIV-1) properties of these compounds were examined.