Smokeless tobacco extracts modulate keratinocyte and fibroblast growth in organotypic culture

Smokeless tobacco is associated with pathologic alterations of the oral mucosa, yet its direct effects on human keratinocytes and fibroblasts in stratified squamous epithelium are not well-understood. We hypothesized that smokeless tobacco could modulate the growth of keratinocytes and fibroblasts in an in vivo-like, organotypic tissue model. To test this, we exposed organotypic cultures for 3 days to smokeless tobacco aqueous extracts and determined the changes in morphology and proliferation of human keratinocytes and fibroblasts. All smokeless tobaccos stimulated keratinocyte proliferation at low doses (0.25% w/v) and suppressed growth at higher doses (> 0.5% w/v). In contrast, smokeless tobacco extracts promoted fibroblast growth at all concentrations without inducing fibroblast turnover. Fibroblasts and keratinocytes, therefore, were differentially affected by smokeless tobacco extracts in an organotypic tissue model, suggesting incipient changes that may occur in vivo.     

Red blood cell membrane mechanical fluctuations in non-proliferative and proliferate diabetic retinopathy

Purpose To study whether cell membrane mechanical fluctuation (CMF) of red blood cells (RBCs) are attenuated in non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR).Patients and methods Point dark-field microscopy-based recordings of local membrane displacements (frequency 0.3–25 Hz) were compared between type 2 diabetes patients with mild-to-moderate and severe NPDR and type 2 diabetes patients with PDR. The matched control group, corresponding to each stage of diabetic retinopathy, was based on non-diabetic patients who were evaluated in our clinic due to cataract.Results The average mean values of the maximal CMF amplitude did not differ between RBCs of NPDR patients (n=20) and controls (n=20) (19.5±1.5% and 19.6±1.7%, respectively). A statistically significant decrease in CMF amplitudes was observed in patients with PDR compared with patients with a non-proliferative disease (NPDR –20%, PDR –90%).Conclusion This new rheological characteristic demonstrates differences in the mechanical properties of RBCs in different stages of diabetic retinopathy. The significant reduction in CMF in patients with PDR may shed more light on the possible mechanism modulating retinal ischemia and leading to angiogenesis in these patients. Larger-scale studies are needed to evaluate these findings and the possible correlation between significantly lower CMF values and the progression of diabetic retinopathy.     

CMF608-a novel mechanical strain-induced bone-specific protein expressed in early osteochondroprogenitor cells

Microarray gene expression analysis was utilized to identify genes upregulated in primary rat calvaria cultures in response to mechanical force. One of the identified genes designated CMF608 appeared to be novel. The corresponding full-length cDNA was cloned and characterized in more details. It encodes a putative 2597 amino acid protein containing N-terminal signal peptide, six leucine-rich repeats (LRRs), and 12 immunoglobulin-like repeats, 10 of which are clustered within the C-terminus. Expression of CMF608 is bone-specific and the main type of CMF608-positive cells is mesenchymal osteochondroprogenitors with fibroblast-like morphology. These cells reside in the perichondral fibrous ring of La Croix, periosteum, endosteum of normal bone as well as in the activated periosteum and early fibrous callus generated postfracture. Expression of CMF608 is notably absent from the regions of endochondral ossification. Mature bone cell types do not produce CMF608 with the exception of chondrocytes of the tangential layer of the articular cartilage, which are thought to be under constant mechanical loading. Ectopic expression of CMF608 in HEK293T cells shows that the protein is subjected to post-translational processing and its N-terminal approximately 90 kDa polypeptide can be found in the conditioned medium. Ectopic expression of either the full-length cDNA of CMF608 or of its N-terminal region in CMF608-negative ROS17/2.8 rat osteosarcoma cells results in transfected clones displaying increased proliferation rate and the characteristics of less-differentiated osteoblasts compared to the control cells. Our data indicate that CMF608 is a unique marker of early osteochondroprogenitor cells. We propose that it could be functionally involved in maintenance of the osteochondroprogenitor cells pool and its down-regulation precedes terminal differentiation.     

Tissue factor and tissue factor pathway inhibitor levels in trophoblast cells: implications for placental hemostasis

The placenta is a highly vascularized organ with fetal and maternal blood supply. Syncytiotrophoblasts (STB), which line the placenta villous are possibly involved in local hemostatic mechanisms. The aim of this study was to evaluate the levels of tissue factor (TF) and its inhibitors, tissue factor pathway inhibitor (TFPI, TFPI-2), in STB model within hemostatic and inflammatory environments. Human primary STB cell cultures were characterized by vascular and hormonal markers. TF and TFPI mRNA expression, protein levels and activity were determined and compared to human umbilical vein endothelial cells (HUVEC). High levels of TF were demonstrated in STB cells compared to low levels in HUVEC. In contrast, STB expressed lower TFPI levels than HUVEC. LPS and TNFalpha increased the high constitutive TF in STB, whereas LPS and IL-1alpha further reduced TFPI levels. The procoagulant tendency of STB identified by us may reflect the physiological need for immediate inhibition of hemorrhage in the placental inter-villous spaces in basal and inflammatory conditions. This hemostatic balance may be critical for normal placental function and pregnancy outcome.     

Histological and scanning electron microscope examination of root canal after preparation with Er:YAG laser microprobe: a preliminary in vitro study

OBJECTIVE: Until now, there has been no study that demonstrates the effectiveness of Er:YAG laser microprobes to clean and shape the root canal without using any mechanical instrumentation. MATERIALS AND METHODS: The study was conducted on 28 single-rooted extracted central incisors teeth with straight roots. Fourteen were mechanically prepared and served as the control group, and 14 were treated by Er:YAG laser only. From every group, half of the teeth were examined histiolgically and half by SEM. The instrument tested was an Er:YAG laser with microprobes 200-400 micro in diameter and 20 mm in length, coupled onto special handpieces, attached to the delivery fiber of an OPUS 20 Er:YAG laser. The Er:YAG laser was applied with the following parameters: wavelength 2.94 microm; pulse duration 400 msec; repetition rate 10 Hz; energy per pulse 140 mJ for the 400 micro microprobe and 90 mJ for the 200-micro microprobe. RESULTS: For the control group, histologically, large amounts of residual pulp tissue were found in the root canal cavity, and open tubules were seen in all the specimens; SEM examination showed very uniform root canal, from apical to cervical portion, high number of open tubules, and different levels of canal debridment. For the study group, histologically, no residual pulp tissue was found in the root canal cavity and open tubules were seen in all the specimens; SEM examination showed the root canal free of debris, removed smear layer, open dentinal tubules, and different levels of enlargement. CONCLUSION: Our results show that the Er:YAG laser special microprobes are effective in shaping, cleaning, and enlarging straight root canals faster and more efficiently then traditional methods.     

From policy to action: access to essential drugs for the treatment of hypertension in the Small Island States (SIS) of the South Pacific

The existing acquisition cost for essential drugs in the Cook Islands, Kiribati, Marshall Islands, Nauru, Niue, Tuvalu, is sufficiently high to compromise equitable access to quality drug therapy. The difficulty of access is further compounded by problems of distance from drug manufacturers and suppliers, associated with inadequate transport and communication links. In some of the Small Island States of the Pacific, internal distribution challenges further reduce access to drugs for those people who live on the outer islands. Two management processes to address these problems which have successfully been used in the past, are the establishment of an essential drug list to guarantee consistent appropriate treatment, and the introduction of pooled or bulk purchasing in order to achieve economies of scale. The major non-communicable diseases (NCDs) in the South Pacific include diabetes, hypertension and cardiovascular disease. These diseases, in association with life-style factors of obesity and smoking result in significant morbidity and mortality. This paper demonstrates that collaboration in drug purchasing of a defined list of essential drugs for hypertension would be beneficial in the South Pacific, and that the process is a model for achievement of rational drug treatment for NCDs in isolated small economies.     

Contrasting effects of aspirin on prostate cancer cells: suppression of proliferation and induction of drug resistance

BACKGROUND: Aspirin is widely used as a preventive measure against occlusive vascular diseases. Since the age group in which aspirin use has become prevalent is similar to the one presenting with prostate cancer, we decided to examine the potential effects of aspirin on prostate cancer. METHODS: We studied the effects of plasma-attainable concentrations of aspirin (0.5-2 mM) on the human prostate cancer cell lines LNCaP, PC-3, and DU 145, employing cytotoxicity assays and flow cytometric analyses. RESULTS: Incubation with aspirin for 3 days reduced cellular proliferation by up to 35-55% in each cell line studied, but induced a tripling of the percentage of cells expressing P-glycoprotein (an efflux pump conferring multidrug resistance) only in the LNCaP cells. Both effects were dose-dependent. The effect on P-glycoprotein expression was reflected in the induction of resistance against adriamycin cytotoxicity. Furthermore, this protective effect of aspirin was reversed by a specific P-glycoprotein inhibitor, PSC833. The cellular expression of P-glycoprotein returned to normal within 3 days following the removal of aspirin. Aspirin did not affect the cell cycle distribution of LNCaP cells. CONCLUSIONS: This study suggests that aspirin enhances the ability of androgen-responsive prostate cancer cells to resist chemotherapeutic drugs. These findings could potentially have significant clinical ramifications for prostate cancer patients taking aspirin shortly before or during chemotherapeutic sessions.     

Toddlers'' Sleep and Temperament: Reporting Bias or a Valid Link? a Research Note

Objective sleep measures derived from a computerized movement detector attached to the child's leg, were obtained for a group of 31 toddlers (mean age: 18.5 months). The monitored sleep parameters were compared with maternal assessment of the child's sleep and her perception of his temperament. The validity of maternal diaries as a measure of the child's sleep was not supported. Nevertheless, a link between both subjective and objective sleep measures with temperament dimensions was indicated. The modest association between sleep and temperament may suggest either a continuity between some aspects of day- and night-time functioning or, alternatively, the influence of the child's sleep behavior in shaping the mother's perceptions of her toddler's temperament.     

Non-visualization of fetal gallbladder in microarray era – a retrospective cohort study and review of the literature

Objective: The objective of this study is to examine the frequency of abnormal Chromosomal Microarray (CMA) analyses among fetuses with isolated non-visualization of fetal gallbladder.

Methods: Data from CMA analyses performed due to isolated non-visualization of fetal gallbladder between January 2013 and September 2016 were retrospectively acquired from a computerized database of the Israeli Ministry of Health. The results were compared with the rate for clinically significant CMA findings in general population, based on a large cohort of 5541 pregnancies undergoing CMA due to maternal request, and a systematic review of 9272 cases with normal ultrasound.

Results: Of 45 pregnancies with isolated non-visualization of fetal gallbladder, CMA testing yielded one (2.22%) gain-of-copy-number variant at 16p11.2, categorized as “pathogenic”. In addition, one finding of unknown significance was demonstrated. The risk for clinically meaningful CMA findings among pregnancies with isolated absent gallbladder was not significantly increased compared to control population.

Conclusions: To the best of our knowledge, this study is the first report describing the rate of pathogenic CMA results in fetuses with isolated non-visualization of fetal gallbladder. The results, in conjunction with previous studies, show that the risk for abnormal CMA results in pregnancies diagnosed with non-visualized gallbladder is not significantly different from pregnancies with normal ultrasound.     

Maternal and neonatal hyponatremia during labor: a case series

Background: Hyponatremia during labor and delivery may result in severe maternal and neonatal sequelae. Our aim was to describe the direct effect of hyponatremia in labor on pregnancy outcome.

Methods: A case series of parturients diagnosed with hyponatremia during labor and their neonates. Clinical presentation, laboratory workup, and maternal and neonatal outcomes are presented.

Results: Four parturients and their corresponding six neonates were diagnosed with hyponatremia. Of these, two cases were caused by water intoxication and two were preeclampsia induced. While two were identified due to maternal or neonatal symptoms, two were diagnosed by routine laboratory testing. In all cases, low maternal sodium resulted in similarly low neonatal sodium. Neonatal symptoms included respiratory distress syndrome (RDS), lethargy, and jaundice.

Conclusion: Psychogenic drinking during labor and preeclampsia may predispose to maternal hyponatremia, resulting in neonatal hyponatremia. Early recognition and treatment can prevent further maternal deterioration and adverse neonatal sequelae.