The premenstrual syndrome. Effects of "medical ovariectomy"

In a crossover study conducted over a six-month period in eight patients with well-characterized premenstrual syndrome, physical and behavioral symptoms were relieved by daily administration of an agonist of gonadotropin-releasing hormone. The reversible "medical ovariectomy" attained with this agonist suggests that it may be an effective and rational treatment for this distressing syndrome in the short term. Whether prolonged therapy would be safe and effective, or even necessary, remains to be determined.

Extraction of perceptually salient contours by striate cortical networks

We present a cortical-based model for computing the perceptual salience of contours embedded in noisy images. It has been suggested that horizontal intra-cortical connections in primary visual cortex may modulate contrast detection thresholds and pre-attentive "pop-out". In our model, horizontal connections mediate context-dependent facilitatory and inhibitory interactions among oriented cells. Strongly facilitated cells undergo temporal synchronization; and perceptual salience is determined by the level of synchronized activity. The model accounts for a range of reported psychophysical and physiological effects of contour salience. In particular, the model proposes that intrinsic properties of synchronization account for the increased salience of smooth, closed contours. Application of the model to real images is demonstrated.

PAK promotes morphological changes by acting upstream of Rac

The serine/threonine kinase p21-activated kinase (PAK) has been implicated as a downstream effector of the small GTPases Rac and Cdc42. While these GTPases evidently induce a variety of morphological changes, the role(s) of PAK remains elusive. Here we report that overexpression of betaPAK in PC12 cells induces a Rac phenotype, including cell spreading/membrane ruffling, and increased lamellipodia formation at growth cones and shafts of nerve growth factor-induced neurites. These effects are still observed in cells expressing kinase-negative or Rac/Cdc42 binding-deficient PAK mutants, indicating that kinase- and p21-binding domains are not involved. Furthermore, lamellipodia formation in all cell lines, including those expressing Rac binding-deficient PAK, is inhibited significantly by dominant-negative RacN17. Equal inhibition is achieved by blocking PAK interaction with the guanine nucleotide exchange factor PIX using a specific N-terminal PAK fragment. We conclude that PAK, via its N-terminal non-catalytic domain, acts upstream of Rac mediating lamellipodia formation through interaction with PIX.

Development and evaluation of a new composite Laserskin graft

BACKGROUND

Tremendous effort has been made to improve the graft take rate of cultured epidermal autograph. The purpose of this study is to develop and evaluate a new composite Laserskin graft (CLSG) as a human skin substitute for wound resurfacing.

METHODS

The seeding efficacy of cultured keratinocytes on plain Laserskin was compared with the 3T3 cell-seeded Laserskin and allogenic fibroblast-populated Laserskin. Three different types of CLSG, 2 cm in diameter each, were prepared and tested in rats. Type A CLSG consisted of proliferative allogenic rat fibroblasts on both sides of the Laserskin with autologous keratinocytes also on the upper side. Fibroblasts and keratinocytes were seeded only on the upper side of the Laserskin in type B CLSG. Keratinocytes alone were seeded on plain Laserskin in type C CLSG. Type B CLSG consisting of autologous keratinocytes and autologous dermal fibroblasts was tested on five selected wounds (5x5 cm each) of a patient with full-thickness burn. In another burn patient, type B CLSG consisting of autologous keratinocytes and allogenic dermal fibroblasts was grafted onto three wounds (5x5 cm each).

RESULTS

The seeding efficacy of human keratinocytes on plain Laserskin increased from 75% to 95% when proliferative allogenic fibroblasts were grown as a feeder layer on the Laserskin. The seeding efficacy of rat keratinocytes increased from 36% to 88% in the presence of a proliferative allogenic fibroblast feeder layer, whereas human/rat keratinocytes had respective seeding efficacy of 98%/91% on Laserskin preseeded with mitomycin C-treated 3T3 cells. Skin biopsies of grafted type A CLSG on day 14 after grafting showed complete epithelialization without severe inflammation in 16 of 20 (80%) grafted surgical wounds in rats. There were eight (40%) and seven (35%) "takes" of the CLSG in types B and C, respectively. The infection rate in type B CLSG was two (10%). There was one (5%) infection in types A and C. The respective take rates on the two patients grafted with type B CLSG were 60% and 100%.

CONCLUSION

The animal experiment and the preliminary clinical data showed that the CSLGs consisting of autologous keratinocytes and of autologous/allogenic fibroblasts are good human skin substitutes in terms of durability, biocompatibility, high seeding efficacy for keratinocytes, high graft take rate, and low infection rate.

Carbon Nanotube/Conducting Polymer Hybrid Nanofibers as Novel Organic Bioelectronic Interfaces for Efficient Removal of Protein-Bound Uremic Toxins

Protein-bound uremic toxins (PBUTs) can cause noxious effects in patients suffering from renal failure as a result of inhibiting the transport of proteins and inducing their structural modification. They are difficult to remove through standard hemodialysis (HD) treatment. Herein, we report an organic bioelectronic HD device system for the effective removal of PBUTs through electrically triggered dissociation of protein-toxin complexes. To prepare this system, we employed electrospinning to fabricate electrically conductive quaternary composite nanofiber mats-comprising multiwalled carbon nanotubes (MWCNTs), poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS), poly(ethylene oxide) (PEO), and (3-glycidyloxypropyl)trimethoxysilane (GOPS)-on conventional polyethersulfone (PES) dialysis membranes. These composite nanofiber platforms exhibited (i) long-term water resistance (due to cross-linking among PSS, PEO, and GOPS), (ii) high adhesion strength on the PES membrane (due to GOPS functioning as an adhesion promoter), (iii) enhanced electrical properties [due to the MWCNTs and PEDOT:PSS promoting effective electrical stimulation (ES) operation in devices containing bioelectronic interfaces (BEI)], and (iv) good anticoagulant ability and negligible hemolysis of red blood cells. We employed this organic BEI electronic system as a novel single-membrane HD device to study the removal efficiency of four kinds of uremic toxins [p-cresol (PC), indoxyl sulfate, and hippuric acid as PBUTs; creatinine as a non-PBUT] as well as the effects of ES on lowering the protein binding ratio. Our organic BEI devices provided a high rate of removal of PC with low protein loss after 4 h of a simulated dialysis process. It also functioned with low complement activation, low contact activation levels, and lower amounts of platelet adsorption, suggesting great suitability for use in developing next-generation bioelectronic medicines for HD.

Formation of Pt-Ru nanoparticles in ethylene glycol solution: an in situ X-ray absorption spectroscopy study

The chemical state and formation mechanism of Pt-Ru nanoparticles (NPs) synthesized by using ethylene glycol (EG) as a reducing agent and their stability have been examined by in situ X-ray absorption spectroscopy (XAS) at the Pt LIII and Ru K edges. It appears that the reduction of Pt(IV) and Ru(III) precursor salts by EG is not a straightforward reaction but involves different intermediate steps. The pH control of the reaction mixture containing Pt(IV) and Ru(III) precursor salts in EG to 11 led to the reduction of Pt(IV) to Pt(II) corresponding to [PtCl4](2-) whereas Ru(III)Cl3 is changed to the [Ru(OH)6](3-) species. Refluxing the mixture containing [PtCl4](2-) and [Ru(OH)6](3-) species at 160 degrees C for 0.5 h produces Pt-Ru NPs as indicated by the presence of Pt and Ru in the first coordination shell of the respective metals. No change in XAS structural parameters is found when the reaction time is further increased, indicating that the Pt-Ru NPs formed are extremely stable and less prone to aggregation. XAS structural parameters suggest a Pt-rich core and a Ru-rich shell structure for the final Pt-Ru NPs. Due to the inherent advantages of the EG reduction method, the atomic distribution and alloying extent of Pt and Ru in the Pt-Ru NPs synthesized by the EG method are higher than those of the Pt-Ru/C NPs synthesized by a modified Watanabe method.

Synthesis of a Highly Hindered Hydrindanone via α-Carbonyl Radical Cyclization: Enantiospecific Formal Syntheses of (−)-Pinguisenol and (−)-α-Pinguisene

An enantiospecific synthesis of Schinzer's ketone 3 from (R)-(+)-pulegone via alpha-carbonyl radical cyclization was accomplished. This work also constitutes an enantiospecific formal syntheses of (-)-pinguisenol and (-)-alpha-pinguisene. The intermediate ketone 4 would be useful for the synthesis of other pinguisane-type sesquiterpenes.

Combination of a new composite biocampatible skin graft on the neodermis of artificial skin in an animal model

INTRODUCTION

There have been very limited and inconsistent attempts at combining the cultured epidermal autograft (CEA) with the neodermis of artificial skin (Integra). The reasons for this remain unknown. The basement membrane proteins of conventional CEA sheets are easily damaged by the dispase treatment during the harvesting of the CEA from the culture flask. The damage of the basement membrane proteins may affect the anchorage of CEA onto the neodermis of Integra. A new Composite Biocompatible Skin Graft (CBSG) was recently developed.

METHODS

Composite biocompatible skin graft consists of autologous keratinocytes cultivated on a pliable hyaluronate-derived membrane (Laserskin)which has been pre-seeded with allogenic dermal fibroblasts. Basement membrane proteins of CBSG are protected from the dispase treatment because the keratinocytes are directly seeded onto Laserskin. The engraftment of CBSG was evaluated on 20 wounds of 10 rats. Integrawas grafted on two freshly excised full-thickness wounds (3cm in diameter) in the dorsum of each animal. A polypropylene ring was applied to each wound to prevent the migration of epithelium from the edges. Composite Biocompatible Skin Graft was used to cover the neodermis of Integra after the silicone membrane was removed 14-21 days postgrafting.

RESULTS

Fourteen (70%) of 20 skin biopsies taken at day 21 from the centre of the grafted wounds revealed regenerated epithelium.

CONCLUSION

A feasible delivery system of cultured keratinocytes onto theneodermis of Integra is demonstrated in this animal -experiment.

The stage-dependent inhibitory effect of porcine follicular cells on the development of preantral follicles

The objective of this study was to examine the effects of follicular cells on the in vitro development of porcine preantral follicles. In Experiment 1, one preantral follicle alone (Trt 1) was cocultured with a follicle of the same size with oocytes (Trt 2) or without oocytes (Trt 3). Preantral follicles cultured alone in vitro for 12 days had greater follicle diameters (1017 +/- 96 microm versus 706 +/- 69 or 793 +/- 72 microm, P < 0.05), growth rates (201 +/- 0.3 versus 103 +/- 0.2 or 128 +/- 0.2, P < 0.05) and oocyte survival rates (73% versus 48, or 25%, P < 0.05) than other groups. The inhibitory effects of follicle cells on the growth of preantral follicles and oocyte survival rates were not enhanced by the addition of oocytectomized preantral follicles (Experiment 2). Follicles were cocultured with different sources of follicular cells in other experiments. Coculture with cumulus cells enhanced oocyte survival compared to the control (without coculture) and mural follicular cell groups (Experiment 3). The growth and survival rates of oocytes collected from the group of follicles cocultured with cumulus cells from large antral follicles (>3 mm) were greater (P < 0.05) than those from small antral follicles (<3 mm), or than the control group (without cumulus cells, experiment 4). No significant differences in the follicular diameters (674 +/- 30 microm versus 638 +/- 33 and 655 +/- 28 microm) and growth rate (105% versus 94 and 105%) were observed among the preantral follicles of the different treatments (P > 0.05). Taken together, coculture with the cells from large antral follicles (>3 mm) exerted a significant positive effect on oocyte survival. The growth and oocyte survival of preantral follicle cocultured with the same size of follicles (with or without oocyte) were inhibited. Growth and survival rates of preantral follicles and oocytes are improved by coculturing them with the cumulus cells derived from larger antral follicles.

Evaluation of the antitumor effects of BPR1J-340, a potent and selective FLT3 inhibitor, alone or in combination with an HDAC inhibitor, vorinostat, in AML cancer

Overexpression or/and activating mutation of FLT3 kinase play a major driving role in the pathogenesis of acute myeloid leukemia (AML). Hence, pharmacologic inhibitors of FLT3 are of therapeutic potential for AML treatment. In this study, BPR1J-340 was identified as a novel potent FLT3 inhibitor by biochemical kinase activity (IC₅₀ approximately 25 nM) and cellular proliferation (GC₅₀ approximately 5 nM) assays. BPR1J-340 inhibited the phosphorylation of FLT3 and STAT5 and triggered apoptosis in FLT3-ITD⁺ AML cells. The pharmacokinetic parameters of BPR1J-340 in rats were determined. BPR1J-340 also demonstrated pronounced tumor growth inhibition and regression in FLT3-ITD⁺ AML murine xenograft models. The combination treatment of the HDAC inhibitor vorinostat (SAHA) with BPR1J-340 synergistically induced apoptosis via Mcl-1 down-regulation in MOLM-13 AML cells, indicating that the combination of selective FLT3 kinase inhibitors and HDAC inhibitors could exhibit clinical benefit in AML therapy. Our results suggest that BPR1J-340 may be further developed in the preclinical and clinical studies as therapeutics in AML treatments.

Discovery of 3-phenyl-1H-5-pyrazolylamine derivatives containing a urea pharmacophore as potent and efficacious inhibitors of FMS-like tyrosine kinase-3 (FLT3)

Preclinical investigations and early clinical trials suggest that FLT3 inhibitors are a viable therapy for acute myeloid leukemia. However, early clinical data have been underwhelming due to incomplete inhibition of FLT3. We have developed 3-phenyl-1H-5-pyrazolylamine as an efficient template for kinase inhibitors. Structure-activity relationships led to the discovery of sulfonamide, carbamate and urea series of FLT3 inhibitors. Previous studies showed that the sulfonamide 4 and carbamate 5 series were potent and selective FLT3 inhibitors with good in vivo efficacy. Herein, we describe the urea series, which we found to be potent inhibitors of FLT3 and VEGFR2. Some inhibited growth of FLT3-mutated MOLM-13 cells more strongly than the FLT3 inhibitors sorafenib (2) and ABT-869 (3). In preliminary in vivo toxicity studies of the four most active compounds, 10f was found to be the least toxic. A further in vivo efficacy study demonstrated that 10f achieved complete tumor regression in a higher proportion of MOLM-13 xenograft mice than 4 and 5 (70% vs 10% and 40%). These results show that compound 10f possesses improved pharmacologic and selectivity profiles and could be more effective than previously disclosed FLT3 inhibitors in the treatment of acute myeloid leukemia.

Identification of a potent 5-phenyl-thiazol-2-ylamine-based inhibitor of FLT3 with activity against drug resistance-conferring point mutations

Numerous FLT3 inhibitors have been explored as a viable therapy for the treatment of acute myeloid leukemia (AML). However, clinical data have been underwhelming due to incomplete inhibition of FLT3 or the emergence of resistant mutations treated with these older agents. We previously developed a series of 3-phenyl-1H-5-pyrazolylamine derivatives as highly potent and selective FLT3 inhibitors with good in vivo efficacy using an intravenous (IV) route. However, the poor bioavailability of these pyrazole compounds limits the development of these promising antileukemic compounds for clinical use. Herein, we describe a novel class of 5-phenyl-thiazol-2-ylamine compounds that are multi-targeted FLT3 inhibitors. From this class of compounds, compound 7h was very potent against AML cell lines and exhibited excellent oral efficacy in AML xenograft models. In addition, further studies demonstrated that compound 7h exhibited potent in vitro and in vivo activities against clinically relevant AC220 (3)-resistant kinase domain mutants of FLT3-ITD.

The efficacy of collagen dermis membrane and fibrin on cultured epidermal graft using an athymic mouse model

A human skin substitute consisting of human cultured keratinocytes, collagen dermis, and fibrin was evaluated in athymic mice. Eighty athymic mice were divided randomly into four groups. A 1.5x1.5-cm full-thickness wound defect was created on the back of each athymic mouse under anesthesia. These wounds were covered by sheets of cultured epidermal graft (group A), cultured epidermal graft with collagen dermis and fibrin (group B), cultured epidermal graft with collagen dermis (group C), or cultured epidermal graft with fibrin (group D). The grafts were secured and kept moist by specially designed saline gauze chambers. The take rates of the cultured graft with more than 50% of the wound covered were 65%, 15%, 50%, and 45% respectively. Group B had a significantly lower graft take rate, however the difference was not significant among groups A, C, and D. Light microscopy of biopsies of the grafted sites at 12 days showed complete epithelialization. The incidence of discharge from wound beds in groups A, B, C, and D was 0%, 15%, 15%, and 10% respectively. The results suggest that cultured cells are best grafted directly onto the wound bed or in combination with either a thin layer of collagen or fibrin but not both because the collagen dermal membrane and the fibrin together may impose too great a diffusion barrier for the cultured cell graft to become vascularized.

PEDOT:PSS-Based Bioelectrodes for Multifunctional Drug Release and Electric Cell-Substrate Impedance Sensing

Electric cell-substrate impedance sensing (ECIS) is an innovative approach for the label-free and real-time detection of cell morphology, growth, and apoptosis, thereby playing an essential role as both a viable alternative and valuable complement to conventional biochemical/pharmaceutical analysis in the field of diagnostics. Constant improvements are naturally sought to further improve the effective range and reliability of this technology. In this study, we developed poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) conducting polymer (CP)-based bioelectrodes integrated into homemade ECIS cell-culture chamber slides for the simultaneous drug release and real-time biosensing of cancer cell viability under drug treatment. The CP comprised tailored PEDOT:PSS, poly(ethylene oxide) (PEO), and (3-glycidyloxypropyl)trimethoxysilane (GOPS) capable of encapsulating antitumor chemotherapeutic agents such as doxorubicin (DOX), docetaxel (DTX), and a DOX/DTX combination. This device can reliably monitor impedance signal changes correlated with cell viability on chips generated by cell adhesion onto a predetermined CP-based working electrode while simultaneously exhibiting excellent properties for both drug encapsulation and on-demand release from another CP-based counter electrode under electrical stimulation (ES) operation. Cyclic voltammetry curves and surface profile data of different CP-based coatings (without or with drugs) were used to analyze the changes in charge capacity and thickness, respectively, thereby further revealing the correlation between their drug-releasing performance under ES operation (determined using ultraviolet-visible (UV-vis) spectroscopy). Finally, antitumor drug screening tests (DOX, DTX, and DOX/DTX combination) were performed on MCF-7 and HeLa cells using our developed CP-based ECIS chip system to monitor the impedance signal changes and their related cell viability results.

3-Phenyl-1H-5-pyrazolylamine-based derivatives as potent and efficacious inhibitors of FMS-like tyrosine kinase-3 (FLT3)

A new class of FLT3 inhibitors has been identified based on the 3-phenyl-1H-5-pyrazolylamine scaffold. The structure-activity relationships led to the discovery of two carbamate series, and some potent compounds within these two series exhibited better growth inhibition of FLT3-mutated MOLM-13 cells than FLT3 inhibitors sorafenib (2) and ABT-869 (3). In particular, compound 8d exhibited the ability to regress tumors in mouse xenograft model using MOLM-13 cells.

Coarse-grain parallel computing for very large scale neural simulations in the NEXUS simulation environment

We describe a neural simulator designed for simulating very large scale models of cortical architectures. This simulator, NEXUS, uses coarse-grain parallel computing by distributing computation and data onto multiple conventional workstations connected via a local area network. Coarse-grain parallel computing offers natural advantages in simulating functionally segregated neural processes. We partition a complete model into modules with locally dense connections--a module may represent a cortical area, column, layer, or functional entity. Asynchronous data communications among workstations are established through the Network File System, which, together with the implicit modularity, decreases communications overhead, and increases overall performance. Coarse-grain parallelism also benefits from the standardization of conventional workstations and LAN, including portability between generations and vendors.

Using time-course as an essential factor to accurately predict sepsis-associated mortality among patients with suspected sepsis

BACKGROUND

Biomarker dynamics in different time-courses might be the primary reason why a static measurement of a single biomarker cannot accurately predict sepsis outcomes. Therefore, we conducted this prospective hospital-based cohort study to simultaneously evaluate the performance of several conventional and novel biomarkers of sepsis in predicting sepsis-associated mortality on different days of illness among patients with suspected sepsis.

METHODS

We evaluated the performance of 15 novel biomarkers including angiopoietin-2, pentraxin 3, sTREM-1, ICAM-1, VCAM-1, sCD14 and 163, E-selectin, P-selectin, TNF-alpha, interferon-gamma, CD64, IL-6, 8, and 10, along with few conventional markers for predicting sepsis-associated mortality. Patients were grouped into quartiles according to the number of days since symptom onset. Receiver operating characteristic curve (ROC) analysis was used to evaluate the biomarker performance.

RESULTS

From 2014 to 2017, 1483 patients were enrolled, of which 78% fulfilled the systemic inflammatory response syndrome criteria, 62% fulfilled the sepsis-3 criteria, 32% had septic shock, and 3.3% developed sepsis-associated mortality. IL-6, pentraxin 3, sCD163, and the blood gas profile demonstrated better performance in the early days of illness, both before and after adjusting for potential confounders (adjusted area under ROC curve [AUROC]:0.81-0.88). Notably, the Sequential Organ Failure Assessment (SOFA) score was relatively consistent throughout the course of illness (adjusted AUROC:0.70-0.91).

CONCLUSION

IL-6, pentraxin 3, sCD163, and the blood gas profile showed excellent predictive accuracy in the early days of illness. The SOFA score was consistently predictive of sepsis-associated mortality throughout the course of illness, with an acceptable performance.

Regulation of insulin-like growth factor binding protein-1 during the 24-hour metabolic clock and in response to hypoinsulinemia induced by fasting and Sandostatin in normal women

OBJECTIVE

To establish the relation of insulin-like growth factor-I (IGF-I) and IGF-binding protein-1 (IGFBP-1) with 24-hour metabolic excursions in normal healthy women and in response to acute interruption of metabolic homeostasis by hypoinsulinemia.

METHODS

Hourly blood samples during the 24-hour metabolic clock were obtained from seven normally cycling women. Uniform dietary composition (50% carbohydrate, 35% fat, and 15% protein) and timing of meals (8 AM, 12 PM, and 6 PM) were prescribed. Daytime hypoinsulinemia was induced by omitting meals and by Sandostatin (100 micrograms) administration. Changes in serum levels of glucose, insulin, cortisol, IGF-I, and IGFBP-1 were measured.

RESULTS

The diurnal pattern of serum IGFBP-1 levels during the 24-hour metabolic clock was characterized by a rapid fall during the feeding phase of the day and a progressive 3.5-fold rise during nocturnal fasting; IGF-I levels were unchanged. Changes in IGFBP-1 levels were in parallel to those of cortisol and were inversely related to increases in glucose (80%) and insulin (tenfold) levels after each meal and to their decline during nocturnal fasting. Daytime fasting and administration of Sandostatin were accompanied by rapid and sustained increases in IGFBP-1 when insulin levels declined to 54 +/- 20 pmol/L.

CONCLUSIONS

With constant levels of IGF-I, the diurnal rhythm of IGFBP-1 may subserve a physiologic function by coordinating insulin and IGF-I action with substrate availability. Fluctuations of insulin levels during the 24-hour metabolic clock in normal women appear to serve as a signal, with an inhibitory effect on IGFBP-1 production when levels are above 70 pmol/L and a stimulatory effect at levels below 70 pmol/L. These findings provide a basis for future investigations in women with nutritionally related reproductive disorders.