Cytoarchitecture of the medial nucleus of trapezoid body of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus, and Carollia perspicillata) with different foraging behavior

The present study was taken to test the hypothesis that the medial nucleus of the trapezoid body (MNTB) of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish-eating), Phyllostomus hastatus (carnivorous/ omnivorous) and Carollia perspicillata (fruit-eating) and were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The results showed that the MNTB is well developed in all the bats in general and the mean length of the MNTB was 1160 ± 124 µm in N. leporinus, 400 ± 59 µm in P. hastatus and 320 ± 25µm in C. perspicillata. The body and brain weight do not reflect proportionately on the size of the MNTB in the present study. The hearing frequency spectrum did not covary with the size of the MNTB among the bats studied. The MNTB is clearly demarcated from the ventral nucleus of the trapezoid body (VNTB) only in P. hastatus. The MNTB comprised mainly three types of cells in all three bats: dense-staining multipolar cells (12.5 µm and 25.0 µm diameter); light-staining multipolar cells measuring (12.5 µm and 25.0 µm diameter) and light-staining round cells (5.0 µm diameter). The large sized MNTB was observed in N. leporinus, which suggests that it relies heavily on echolocation whereas P. hastatus and C. perspicillata use echolocation as well but also rely on hearing, smell and vision.

Multi-Analytical Investigation of Stains on Dimension Stones in Master Valentim’s Fountain, Brazil

Master Valentim’s fountain has become an important historical patrimony for Brazil, being portrayed by famous artists, among them Jean-Baptiste Debret. In 1938, it was registered as cultural heritage by the Brazilian National Historical and Artistic Heritage Institute (IPHAN), and in 1990 it was subjected to excavation and restoration works. The fountain was built in Gneiss and Lioz limestone, with metallic plates and mortar connecting the Gneiss blocks. Currently, deteriorations in the fountain stones can be observed, such as light stains and some aesthetic modifications caused by inadequate restorations. Petrography, X-ray fluorescence (XRF), XRD, physical properties, colorimetry, electrical conductivity, inductively coupled plasma optical emission spectrometry (ICP-OES), scanning electron microscopy-energy dispersive X-ray (SEM-EDX), and TGA were performed in order to characterize the Gneiss blocks, the metallic plates, and the stones used in previous restorations, as well as light stains observed on the Gneiss blocks. The petrography and XRD analyses inferred that the light stains may have been caused by the formation of an insoluble salt as a result of the association of the lead from the plates with other elements. The XRD analysis on the light staining area indicated the presence of cerussite (PbCO3) and anglesite (PbSO4), which are the probable cause of the light stains. The SEM-EDX results suggested that sulfur is the main element associated to lead.

Multi-Analytical Investigation of Stains on Dimension Stones in Master Valentim’s Fountain, Brazil

Master Valentim’s fountain became an important historical patrimony for Brazil, being portrayed by famous artists among them Jean-Baptiste Debret. In 1938, it was registered as cultural heritage by the Brazilian National Historical and Artistic Heritage Institute (IPHAN), and in 1990 it was subjected to excavation and restoration works. The fountain was built in Gneiss and Lioz limestone, with metallic plates and mortar connecting the Gneiss blocks. Currently, deteriorations in the fountain stones can be observed such as light stains and some aesthetic modifications caused by inadequate restorations. Petrography, XRF, XRD, Physical Properties, Colorimetry, Electrical Conductivity, ICP-OES, SEM-EDX, and TGA were performed in order to characterize the Gneiss blocks, the metallic plates, the stones used in previous restorations, as well as light stains observed on the Gneiss blocks. The petrography and XRD analyses inferred that light stains may have been caused by the formation of an insoluble salt as a result of the association of the lead from the plates with other elements. The XRD analysis on the light staining area indicated presence of cerussite (PbCO3), and anglesite (PbSO4), which are the probable cause of the light stains. The SEM-EDX results suggested that sulfur is the main element associated to lead.

Quantification of polysaccharides fixed to Gram stained slides using lactophenol cotton blue and digital image processing

Dark blue rings and circles emerged when the non-specific polysaccharide stain lactophenol cotton blue was added to Gram stained slides. The dark blue staining is attributable to the presence of capsular polysaccharides and bacterial slime associated with clumps of Gram-negative bacteria. Since all bacterial cells are glycosylated and concentrate polysaccharides from the media, the majority of cells stain light blue. The contrast between dark and light staining is sufficient to enable a digital image processing thresholding technique to be quantitative with little background noise. Prior to the addition of lactophenol cotton blue, the Gram-stained slides appeared unremarkable, lacking ubiquitous clumps or stained polysaccharides. Adding lactophenol cotton blue to Gram stained slides is a quick and inexpensive way to screen cell cultures for bacterial slime, clumps and biofilms that are invisible using the Gram stain alone.

Diagnostic accuracy of chromohysteroscopy in women with unexplained infertility

Background: Chronic endometritis has been related to infertility but it is usually asymptomatic and the diagnosis is rarely suspected clinically. In cases of absence of any macroscopic abnormalities during conventional hysteroscopy, endometrial dyeing using methylene blue help identify abnormal areas and coupled with the histopathological examination gives a better diagnosis of endometritis.Methods: This study was conducted on 100 infertile women in Department of Obstetrics and Gynecology at Lady Hardinge Medical College, New Delhi over a period of one year. All women under- went hysteroscopy followed by chromohysteroscopy using 1% methylene blue dye. Biopsy was taken from light and dark stained areas. The histopathology results of these samples were compared and analyzed in relation with hysteroscopic and chromohysteroscopic findings and diagnostic accuracy calculated.Results: Out of 100 women who underwent dianostic hysteroscopy 68 cases had normal findings and 32 had abnormal finding and on chromohysteroscopy light staining pattern was seen in 56 cases and 44 cases had dark staining. Histopathology of biopsy tissue from these dark stained areas showed endometritis in 50% (22 out of 44 cases) and normal endometrium in 50% (22 out of 44) cases, and biopsy from light stained area showed chronic endometritis in 5.35% (3 out of 56) cases and remaining 94.65% had normal endometrium. Diagnostic accuracy of chromohysteroscopy were sensitivity=88%, specificity=70.66%, PPV=50%, NPV=94.6%.Conclusions: Chromohysteroscopy is a simple and effective technique for diagnosing endometrial pathology in cases of infertility.

Quantification of polysaccharides fixed to Gram stained slides using lactophenol cotton blue and digital image processing

Indigo rings and circles emerged when I added the non-specific polysaccharide stain lactophenol cotton blue to Gram stained slides. I attribute the dark blue staining to the presence of capsular polysaccharides and bacterial slime associated with clumps of Gram-negative bacteria. Since all bacterial cells are glycosylated and concentrate polysaccharides from the media, the majority of cells stain light blue. The contrast between dark and light staining is sufficient to enable a digital image processing thresholding technique to be quantitative with little background noise. Prior to the addition of lactophenol cotton blue, the Gram-stained slides appeared unremarkable, lacking ubiquitous clumps or stained polysaccharides. Adding lactophenol cotton blue to Gram stained slides is a quick and inexpensive way to screen cell cultures for bacterial slime, clumps and biofilms that are invisible using the Gram stain alone.

Quantification of polysaccharides fixed to Gram stained slides using lactophenol cotton blue and digital image processing

I discovered indigo rings and circles inEscherichia coliATCC® 25922™ cultures when I added the non-specific polysaccharide stain lactophenol cotton blue to Gram stained slides sampled from 96-well plates used to measure quantitative growth kinetics (QGK) in virtual colony count antimicrobial assays. I attribute the dark blue staining to the presence of capsular polysaccharides and bacterial slime associated with clumps of cells. Since all bacterial cells are glycosylated, the majority of cells stain light blue. The contrast between dark and light staining is sufficient to enable a digital image processing thresholding technique to be quantitative for circular or ring-shaped structures that imply the presence of slime fixed to the glass. These polysaccharides indicate a possible mechanism of resistance to antimicrobial peptides such as defensins, lectins with high affinity for polysaccharides and glycosylated proteins. Adding lactophenol cotton blue to Gram stained slides is a quick and inexpensive way to screen cell cultures for bacterial slime, clumps and biofilms, revealing details of polysaccharide secretion that are missed using the Gram stain alone. Combined with QGK threshold times, the lactophenol cotton blue Gram stain followed by digital image processing provides quantitative information useful for quality control, environmental monitoring and detection of clumping environmental factors.

Pseudopodial silica absorption hypothesis (PSA hypothesis): a new function of pseudopodia in living radiolarian polycystine cells

The secretion process of the siliceous skeleton in polycystine radiolarians has drawn a great deal of interest during the last century; however, little is known about the actual physiological process of silica deposition. Recently, the PDMPO (2-(4-pyridyl)-5-[(4-(2-dimethylaminoethylaminocarbamoyl) methoxy)-phenyl] oxazole) method for staining silica deposition sites in polycystines was developed. In the present study we examined over 30 polycystine cells with PDMPO and found that both the skeletons and pseudopodia of three species (Lithelius sp., Rhizosphaera trigonacantha and Arachnosphaera hexasphaera) were stained and emitted green fluorescent light. Staining of the skeleton was probably the result of skeletal thickening growth, whereas staining of the pseudopodia may indicate that siliceous matter is assimilated within pseudopodia. We refer to this hypothesis as the ‘pseudopodial silica absorption hypothesis’ (PSA hypothesis). If this hypothesis is correct, PSA is an intermittent process, and the absorbed silica within pseudopodia is quickly transferred to the cytokalymma where it is deposited on the skeleton. To date, the PSA process has been observed in only the three species cited above; therefore we are unable to evaluate whether the PSA process is unique to these species or a common process that occurs in all polycystines; further investigation is necessary.

Survivin is a critical regulator of spindle organization and chromosome segregation during rat oocyte meiotic maturation

SummarySurvivin is a novel member of the inhibitor of apoptosis gene family that bear baculoviral IAP repeats (BIRs), whose physiological roles in regulating meiotic cell cycle need to be determined. Confocal microscopy was employed to observe the localization of survivin in rat oocytes. At the germinal vesicle (GV) stage, survivin was mainly concentrated in the GV. At the prometaphase I (pro-MI) and metaphase I (MI) stage, survivin was mainly localized at the kinetochores, with a light staining detected on the chromosomes. After transition to anaphase I or telophase I stage, survivin migrated to the midbody, and signals on the kinetochores and chromosomes disappeared. At metaphase II (MII) stage, survivin became mainly localized at the kinetochores again. Microinjection of oocytes with anti-survivin antibodies at the beginning of the meiosis, thus blocking the normal function of survivin, resulted in abnormal spindle assembly, chromosome segregation and first polar body emission. These results suggest that survivin is involved in regulating the meiotic cell cycle in rat oocytes.

Persistence of Streptococcus mutans in Stationary-Phase Batch Cultures and Biofilms

ABSTRACT Streptococcus mutans is a member of oral plaque biofilms and is considered the major etiological agent of dental caries. We have characterized the survival of S. mutans strain UA159 in both batch cultures and biofilms. Bacteria grown in batch cultures in a chemically defined medium, FMC, containing an excess of glucose or sucrose caused the pH to decrease to 4.0 at the entry into stationary phase, and they survived for about 3 days. Survival was extended up to 11 days when the medium contained a limiting concentration of glucose or sucrose that was depleted by the time the bacteria reached stationary phase. Sugar-limited cultures maintained a pH of 7.0 throughout stationary phase. Their survival was shortened to 3 days by the addition of exogenous lactic acid at the entry into stationary phase. Sugar starvation did not lead to comparable survival in biofilms. Although the pH remained at 7.0, bacteria could no longer be cultured from biofilms 4 days after the imposition of glucose or sucrose starvation; BacLight staining results did not agree with survival results based on culturability. In both batch cultures and biofilms, survival could be extended by the addition of 0.5% mucin to the medium. Batch survival increased to an average of 26 (±8) days, and an average of 2.7 × 105 CFU per chamber were still present in biofilms that were starved of sucrose for 12 days.