Susceptibility to persistent breeding-induced endometritis in the mare: relationship to endometrial biopsy score and age, and variations between seasons

The objectives were to: (1) investigate the associations of age and endometrial biopsy score with uterine fluid retention after insemination; and (2) determine if a strict classification of susceptibility to persistent breeding-induced endometritis (PBIE) based on biopsy score, endometrial cytology, and fluid retention after inseminations, is consistent over subsequent breeding seasons. In Experiment 1, 57 mares were inseminated with 10⁹ freeze-killed sperm during estrus and evaluated for uterine fluid retention 48 h and 96 h after insemination. Comparisons were made between fluid retention and biopsy score or age. In Experiment 2, a subset of 14 mares was classified for susceptibility to persistent breeding-induced endometritis in two subsequent breeding seasons. Biopsy score and age were associated with fluid retention (P < 0.001). In addition, age was related to biopsy score (P < 0.001). Of the mares examined for susceptibility, 36% (5 of 14) changed status during subsequent seasons. Three mares changed to a more severe classification (intermediate to susceptible, or resistant to intermediate), whereas two mares changed to a less severe classification (susceptible to intermediate).     

Endometrial cytology and computerized morphometric analysis of epithelial nuclei: A useful tool for reproductive diagnosis in the bitch

New diagnostic approaches are required to recognize early canine hypofertility or infertility. We suggest that the identification of different cytologic types, cellular aspects, and nuclear features of the endometrial epithelial cells may be suitable for this purpose. This study was performed on the bitch (Canis familiaris) during the physiologic reproductive cycle and in uterine diseases. We also applied computerized cytomorphometry to evaluate nuclear area, perimeter, diameter, density, aspect, and roundness of endometrial epithelial cells in healthy dogs (N = 35) at different stages of the reproductive cycle (before puberty, during proestrus, estrus, diestrus, and anestrus) and in bitches affected by uterine disorders (N = 10). The stage of the estrous cycle was determined by vaginal cytology and progesterone evaluation and also confirmed by clinical and histologic observations. Samples for endometrial cytology were collected in vivo by uterine flushing with transcervical uterine cannulation. After uterine sampling, each dog underwent OHE or uterine stump revision. Cytologic analyses were compared with histologic examinations to verify the uterine condition. The uterine cellular population was represented by endometrial epithelial cells, erythrocytes, neutrophils, lymphocytes, eosinophils, macrophages, plasma cells, and cervical or incidental vaginal cells. Bacteria and amorphous material were observed. The proportion of different cells and nuclear features in the cytologic samples varied throughout the stages of the reproductive cycle and between normal and pathologic uterine conditions. The computer-assisted nuclear morphometry, performed in cytologic specimens by means of the six nuclear parameters chosen to evaluate the endometrial epithelial cell population, proved to be useful for determining the stage of the reproductive cycle. Furthermore, this system was demonstrated to be a valid support to diagnose and distinguish uterine disorders.     

Chemical correlates of reproduction and worker policing in a myrmicine ant

In a number of wasps, bees, and in particular ponerine ants, quantitative and qualitative variation in the profile of cuticular hydrocarbons is associated with variation in fecundity and is likely to serve for communicating the reproductive status of an individual. Here, we demonstrate that the chemical profile on the cuticle of fertile workers and queens of the myrmicine ant Temnothorax unifasciatus is different from that of non-reproductive workers. Fertility and apparently also cuticular signatures are reversible under the influence of policing by worker aggression. Though no policing by egg-eating occurs in this species, queen and worker laid eggs also differed in their chemical profile.     

Inhibition of prostaglandin F2alpha synthesis and oxytocin receptor by progesterone antagonists in bovine endometrial cells in vitro

Oxytocin receptor (OTR) expression is suppressed by progesterone (P4) during the luteal phase of the estrous cycle and then it increases at the time of luteolysis, but its regulation is still not completely understood. In vitro studies to determine the mechanism of action are hindered because OTR spontaneously upregulates in vitro and it is impossible to alter expression with P4 or estradiol. During recent studies examining the effect of P4 and an antagonist (mifepristone) on PG secretion, we found that mifepristone attenuated OT-stimulated PG secretion from endometrial epithelial cells. The objective of the present study was to determine, whether this effect of mifepristone was due to changes in prostaglandin synthesis and/or OTR. A time-course showed that mifepristone (5 microM) had no significant effect after 24 h but by 72 h it decreased PGF(2alpha) secretion (P<0.01) and abolished the response of the cells to OT (P<0.01). The presence or absence of P4 did not affect the response to mifepristone. To determine the site of action of mifepristone, cells were cultured for 72 h with or without mifepristone and then COX-1 and COX-2 were measured by Western blotting and OTR was measured by saturation analysis. The results showed that mifepristone did not affect basal or PMA-stimulated expression of either COX-1 or COX-2 but did, however, decrease OTR number (P<0.05). These data demonstrate that OTR and the response to OT can be downregulated in endometrial epithelial cells in vitro via a mechanism involving the P4 receptor.     

Endogenous cannabinoids: metabolism and their role in reproduction

Over the past two decades a number of endogenous compounds that act as ligands for the cannabinoid receptors has been discovered. In analogy with the "endorphins" these compounds have been called "endocannabinoids". Endocannabinoids have been demonstrated in many mammalian tissues including humans and are widely distributed in the CNS, peripheral nerves, uterus, leukocytes, spleen and testicles. The uterus contains the highest levels of anandamide, the first discovered endocannabinoid, suggesting an important role for this substance in reproduction. Several studies have shown anandamide to be involved in the regulation of implantation and reduced activity of the enzyme that degrades anandamide has been associated with early pregnancy loss in humans. The bulk of the literature concerning endocannabinoids is based upon anandamide related studies; therefore, in this review we focus on the metabolism of anandamide and its role in reproduction.     

Establishing life is a calcium-dependent TRiP: Transient receptor potential channels in reproduction

Calcium plays a key role in many different steps of the reproduction process, from germ cell maturation to placental development. However, the exact function and regulation of calcium throughout subsequent reproductive events remains rather enigmatic. Successful pregnancy requires the establishment of a complex dialogue between the implanting embryo and the endometrium. On the one hand, endometrial cell will undergo massive changes to support an implanting embryo, including stromal cell decidualization. On the other hand, trophoblast cells from the trophectoderm surrounding the inner cell mass will differentiate and acquire new functions such as hormone secretion, invasion and migration. The need for calcium in the different gestational processes implicates the presence of specialized ion channels to regulate calcium homeostasis. The superfamily of transient receptor potential (TRP) channels is a class of calcium permeable ion channels that is involved in the transformation of extracellular stimuli into the influx of calcium, inducing and coordinating underlying signaling pathways. Although the necessity of calcium throughout reproduction cannot be negated, the expression and functionality of TRP channels throughout gestation remains elusive. This review provides an overview of the current evidence regarding the expression and function of TRP channels in reproduction.     

Imprint cytology of vacuum-assisted breast biopsy specimens: a rapid diagnostic tool in non-palpable solid lesions

Objective:  Imprint cytology provides a rapid preliminary diagnosis shortly after the completion of breast biopsy. This study aims to assess the validity of imprint cytology for the pre-operative diagnosis of non-palpable mammographic solid lesions excised by vacuum-assisted breast biopsy (VABB).
Methods:  Seventy-two women with non-palpable Breast Imaging Reporting and Data System 3 and 4 mammographic solid lesions without microcalcifications underwent VABB on the stereotactic Fischer's table with 11-G Mammotome vacuum probes. Imprint samples were examined (Diff-Quick stain, modified Papanicolaou stain and May-Grünwald–Giemsa). The cores were dipped into a CytoRich Red Collection fluid for a few seconds in order to obtain samples with the use of the specimen wash. After the completion of cytological procedures, the core was prepared for routine pathological study. The pathologist was blind to the preliminary cytological results. The cytological and pathological diagnoses were comparatively evaluated.
Results:  The sensitivity of the cytological imprints for cancer was 90%. The specificity of the method for cancer diagnosis was 100%. Two precursor lesions were present in the material: one case of atypical ductal hyperplasia, which was successfully detected, and one case of lobular neoplasia, which escaped detection. The cytological imprints were inadequate in four out of 72 cases (5.6%), but none of them were included within the malignant subgroup.
Conclusions:  Imprint cytology seems to be an important adjunctive tool in the management of patients with non-palpable mammographic solid lesions. Its very satisfactory sensitivity and optimal specificity could establish its use in general clinical practice.     

Delayed uterine fluid clearance and reduced uterine perfusion in bitches with endometrial hyperplasia and clinical management with postmating antibiotic

In many species a transient uterine inflammatory response follows mating and is proposed to remove excess spermatozoa, bacteria, and other contaminants from the uterus. Similar events have been documented in the bitch involving increased uterine contractions, polymorphonuclear neutrophil influx and uterine artery vasodilation. Some healthy bitches with endometrial hyperplasia have increased numbers of uterine luminal polymorphonuclear neutrophils after mating and reduced fertility; it is purported that this represents a presumed postmating endometritis. This study used B-mode and Doppler ultrasonography at the time of mating to measure uterine contractions, clearance of ejaculated fluid, and uterine artery velocity in normal bitches and those with endometrial hyperplasia. Mating resulted in an increase in the number of uterine contractions, although fewer mating-induced contractions were noted in bitches with endometrial hyperplasia. Interestingly, uterine fluid cleared significantly more slowly after mating from the bitches with endometrial hyperplasia than the normal bitches (P = 0.01). In a further study, Doppler ultrasonography showed that in normal bitches there was a significant increase in uterine artery blood velocity (P = 0.04) and a decrease in the resistance index after mating (P = 0.04), indicating vasodilation. In bitches with endometrial hyperplasia the baseline resistance index was significantly higher than normal bitches (P = 0.05), and furthermore, although there was a significant decrease in resistance index after mating, in the bitches with endometrial hyperplasia this was of a smaller magnitude that in normal bitches. These findings indicate lower baseline uterine perfusion, and a blunted vasodilation response to mating in bitches with endometrial hyperplasia. Short-duration postmating administration of systemic antibiotic increased pregnancy rates in bitches with endometrial hyperplasia (P < 0.01). Litter sizes in bitches with endometrial hyperplasia were lower than those of normal bitches both before and after treatment with postmating antibiotic (P = 0.04 and < 0.01, respectively). Mating-induced endometritis in bitches with endometrial hyperplasia appears to affect fertility by reducing the uterine vasodilatory response to mating and delaying clearance of uterine fluid as a result of decreased uterine contractions but the effect can be ameliorated in part by the postmating administration of antibiotic.     

Life history of a neotropical marsupial: Evaluating potential contributions of survival and reproduction to population growth rate

The relative effect of survival and reproductive rates to population growth rate is expected to be similar across species with similar life-histories. We employed a matrix population model and sensitivity and elasticity analysis to assess the absolute and relative importance of age-specific survival and fertility to population growth rate of Didelphis aurita (Didelphimorphia, Didelphidae) in a rural area of Rio de Janeiro, southeastern Brazil. The results were compared to expectations for mammals that mature early and have short generation time, such as D. aurita. Prospective analysis showed that changes in pouch young and juveniles survival would have large effects on population growth rate, relative to other vital rates, being the most critical time periods in the life cycle of D. aurita, whereas the effect of fertilities were always low. These findings do not fit to the observed pattern in mammals that mature early, where reproductive parameters have the largest relative influence on population growth rate. Although reproductive rates were characterized by a relatively small influence on population growth rate, they are still relevant because of their high variability and response to potential environmental disturbances. The first application of matrix population models to a neotropical rainforest marsupial provides information on marsupial demography and life-history strategy, increasing comprehension of this unknown group.     

Deriving multipotent stem cells from mouse spermatogonial stem cells: a new tool for developmental and clinical research

In recent years, embryonic stem (ES) cell-like cells have been obtained from cultured mouse spermatogonial stem cells (SSCs). These advances have shown that SSCs can transition from being the stem cell-producing cells of spermatogenesis to being multipotent cells that can differentiate into derivatives of all three germ layers. As such, they offer new possibilities for studying the mechanisms that regulate stem cell differentiation. The extension of these findings to human SSCs offers a route to obtaining personalized ES-like or differentiated cells for use in regenerative medicine. Here, we compare the different approaches used to derive ES-like cells from SSCs and discuss their importance to clinical and developmental research.     

PEG-mediated transient gene expression and silencing system in maize mesophyll protoplasts: a valuable tool for signal transduction study in maize

Polyethylene glycol (PEG)-mediated transient gene expression and silencing in protoplasts is widely applied in model plants such as Arabidopsis thaliana and rice. Here, we developed an efficient transient gene expression system based on the PEG-mediated method both in etiolated and green maize mesophyll protoplasts. The results showed that both yellow fluorescent protein encoding gene and glucuronidase encoding gene were efficiently expressed in maize protoplasts. More importantly, double-stranded RNAs (dsRNAs) can also be transfected into maize protoplasts by the PEG-mediated method to specifically silence exogenous and endogenous genes. Our results showed that dsRNA can be used to knockdown both exogenous and endogenous gene expression. Furthermore, bimolecular fluorescence complementation system for the detection of protein–protein interactions in maize protoplasts was developed. We also overexpressed and knockdowned the mitogen-activated protein kinase encoding gene ZmMPK5 to investigate the role of ZmMPK5 in abscisic acid (ABA)-induced antioxidant defense in maize protoplasts. This method here we reported will be valuable for signal transduction study in maize.     

Nutriproteomics: a promising tool to link diet and diseases in nutritional research

Nutriproteomics is a nascent research arena, exploiting the dynamics of proteomic tools to characterize molecular and cellular changes in protein expression and function on a global level as well as judging the interaction of proteins with food nutrients. As nutrients are present in complex mixtures, the bioavailability and functions of each nutrient can be influenced by the presence of other nutrients/compounds and interactions. The first half of this review focuses on the techniques used as nutriproteomic tools for identification, quantification, characterization and analyses of proteins including, two-dimensional polyacrylamide electrophoresis, chromatography, mass spectrometry, microarray and other emerging technologies involving visual proteomics. The second half narrates the potential of nutriproteomics in medical and nutritional research for revolutionizing biomarker and drug development, nutraceutical discovery, biological process modeling, preclinical nutrition linking diet and diseases and structuring ways to a personalized nutrition. Though several challenges such as protein dynamics, analytical complexity, cost and resolution still exist, the scope of applying proteomics to nutrition is rapidly expanding and promising as more holistic strategies are emerging.     

Low-vacuum electron microscopy of carabid chemoreceptors: a new tool for the identification of live and valuable museum specimens

High-vacuum scanning electron microscopy, following coating of specimens with gold, produces high quality images that have proved invaluable for the study of insect sensilla. Unfortunately, the technique is essentially destructive, and cannot be used on live or valuable museum specimens. In particular, high-vacuum scanning usually causes the collapse of the tips of the palps, interfering with any examination of the sensilla in this area. A new low-vacuum technique is described that avoids these problems. Insect cuticle does not need to be coated with gold, thus avoiding damage to important specimens. Examples are given of scans of the palp tips of live carabid beetles, anaesthetised with CO₂. It was shown that the technique could consistently display these tips in their natural convex state. In all, four types of sensilla were identified by low-vacuum scans of the maxillary palps, and four further types on the terminal segment of the antennae, plus glandular openings. The antennae revealed a type of sensilla that has not previously been described on carabids. These sensilla showed clear structural differences between the two species studied, Pterostichus melanarius Illiger and P. niger Schaller (Coleoptera: Carabidae), and can be used as a diagnostic character for both fresh and dried specimens. The low-vacuum technique can be recommended for examining valuable type specimens without risk of damage.     

Flower-like terminal structures in racemose inflorescences: a tool in morphogenetic and evolutionary research

Terminal flower-like structures (TFLS) occur in many angiosperms that possess indeterminate inflorescences such as spikes, racemes, or spadices. We describe and review TFLS in early-divergent angiosperms, especially the magnoliid order Piperales and the monocot order Alismatales, in which floral interpretation is controversial. Essentially similar TFLS occur in a wide range of taxa. Among magnoliids, they occur in some Piperales (Saururaceae and a few Piperaceae), but are absent from Chloranthaceae. Among monocots, they occur in some early-divergent families such as Acoraceae, Aponogetonaceae, Juncaginaceae, Potamogetonaceae, and Ruppiaceae. Similar TFLS with obscure organ identity are recorded in mutants of Arabidopsis. TFLS can often be interpreted as pseudanthia (close aggregations of reduced flowers), but in some cases the entire terminal pseudanthium is very similar to a true flower. In some cases, elaborated TFLS could therefore have given rise to what are normally termed 'true' (i.e. euanthial) flowers. Data presented here on terminal pseudanthia in Potamogeton and Ruppia support a pseudanthial evolutionary origin of reproductive units in the alismatid families Zannichelliaceae and Cymodoceaceae. Furthermore, in some alismatid species, either the entire inflorescence apex or an individual primordium at or near the inflorescence tip can be transformed into a filamentous or tubular (or intermediate) structure. A tubular structure enclosing stamens and carpels is described in Piper. This indicates that pseudanthium formation can provoke morphological novelties, perhaps due to new patterns of overlap between expression zones of regulatory genes and/or new spatial constraints.     

Laminin-5 immunocytochemistry: a new tool for identifying dysplastic cells in oral brush biopsies

BACKGROUND: The brush biopsy technique is not only a seminal technique but also a critically discussed method for detection of oral pre-cancerous stages and manifest carcinomas. The gamma2 chain of laminin-5 and its proteolytic fragments comprise an invasion factor for many carcinomas. OBJECTIVES: The aim of this study was to determine whether the immunocytochemical presentation of the laminin gamma2 chain identifies pre-invasive or invasive squamous cells in brush biopsies. METHODS: The value-based identification of atypical epithelia was analysed in 93 consecutive brush biopsies with histopathological diagnoses: standardized haematoxylin and eosin staining; standardized immunocytochemistry: monoclonal antibodies against laminin gamma2 chain: D4B5, 4G1, detection using ChemMate and Autostainer. RESULTS: Conventional cytology did not result in any false-positive cases, i.e. atypical cells in normal, inflamed or benignly hyperproliferative mucosa (specificity, 100%), whereas immunocytochemistry revealed one false-positive case (specificity, 98%). In brush biopsies of oral squamous cell carcinomas, the following immunocytochemical patterns were possible: (1) staining of the cytoplasm, (2) banded markings between clumped carcinoma cells and (3) positive hazes surrounding atypical cells. Bacterial colonies appeared as false-positive results. Four of 27 carcinomas and one of three recurrences were not cytologically identified (sensitivity of conventional cytology, 79%). Three of the five carcinomas not identified by cytology were immunocytochemically stained with laminin gamma2 chain antibody (sensitivity of laminin gamma2 chain immunocytochemistry, 93%). The positive predictive value was 100% for conventional cytology and 97% for laminin gamma2 chain immunocytochemistry. The negative predictive value attained was 92% for conventional cytology and 97% for laminin gamma2 chain immunocytochemistry. CONCLUSIONS: The high sensitivity level observed for method-enhanced brush cytology suggests that this technique be used as an initial diagnostic step.