Anti-Müllerian hormone promotes pre-antral follicle growth, but inhibits antral follicle maturation and dominant follicle selection in primates.

STUDY QUESTION: What are the direct effects and physiological role of anti-Müllerian hormone (AMH) during primate follicular development and function at specific stages of folliculogenesis? SUMMARY ANSWER: AMH actions in the primate ovary may be stage-dependent, directly promoting pre-antral follicle growth while inhibiting antral follicle maturation and dominant follicle selection. WHAT IS KNOWN ALREADY: AMH is expressed in the adult ovary, particularly in developing follicles. Studies in mice suggest that AMH suppresses pre-antral follicle growth in vitro, and inhibits primordial follicle recruitment and FSH-stimulated antral follicle steroidogenesis. STUDY DESIGN, SIZE, DURATION: For in vitro study, secondary follicles were isolated from ovaries of 12 rhesus macaques and cultured for 5 weeks. For in vivo study, intraovarian infusion was conducted on five monkeys for the entire follicular phase during two spontaneous menstrual cycles. PARTICIPANTS/MATERIALS, SETTING, METHODS: For in vitro study, individual follicles were cultured in a 5% O2 environment, in alpha minimum essential medium supplemented with recombinant human FSH. Follicles were randomly assigned to treatments of recombinant human AMH protein or neutralizing anti-human AMH antibody (AMH-Ab). Follicle survival, growth, steroid production, steroidogenic enzyme expression, and oocyte maturation were assessed. For in vivo study, ovaries were infused with control vehicle or AMH-Ab during the follicular phase of the menstrual cycle. Cycle length, serum steroid levels, and antral follicle growth were evaluated. MAIN RESULTS AND THE ROLE OF CHANCE: AMH exposure during culture weeks 0-3 (pre-antral stage) promoted, while AMH-Ab delayed, antrum formation of growing follicles compared with controls. AMH treatment during culture weeks 3-5 (antral stage) decreased (P < 0.05) estradiol (E2) production, as well as the mRNA expression of cytochrome P450 family 19 subfamily A polypeptide 1, by antral follicles relative to controls, whereas AMH-Ab increased (P < 0.05) follicular mRNA levels of the enzyme. Intraovarian infusion of AMH-Ab during the follicular phase of the menstrual cycle increased (P < 0.05) the average levels of serum E2 compared with those of the control cycles. Three of the five AMH-Ab-treated ovaries displayed multiple (n = 2-9) medium-to-large (2-8 mm) antral follicles at the mid-cycle E2 peak, whereas only one large (4-7 mm) antral follicle was observed in all monkeys during their control cycles. The average levels of serum progesterone were higher (P < 0.05) during the luteal phase of cycles following the AMH-Ab infusion relative to the vehicle infusion. LIMITATIONS, REASONS FOR CAUTION: The in vitro study of AMH actions on cultured individual macaque follicles was limited to the interval from the secondary to small antral stage. A sequential study design was used for in vivo experiments, which may limit the power of the study. WIDER IMPLICATIONS OF THE FINDINGS: The current study provides novel information on direct actions and role of AMH during primate follicular development, and selection of a dominant follicle by the late follicular phase of the menstrual cycle. We hypothesize that AMH acts positively on follicular growth during the pre-antral stage in primates, but negatively impacts antral follicle maturation, which is different from what is reported in the mouse model. STUDY FUNDING/COMPETING INTERESTS: NIH NICHD R01HD082208, NIH ORWH/NICHD K12HD043488 (BIRCWH), NIH OD P51OD011092 (ONPRC), Collins Medical Trust. There are no conflicts of interest. TRIAL REGISTRATION NUMBER: Not applicable.

Metformin activates AMPK and mTOR to Inhibit RANKL-stimulated osteoclast formation.

OBJECTIVE: Metformin is a medication used to treat type 2 diabetes by inhibiting hepatic glucose production through adenosine monophosphate-activated protein kinase (AMPK) activation. Autophagy is closely related to the homeostasis and stress mechanisms of the body. In recent years, much research has arisen on therapeutic methods utilizing autophagy mechanisms to treat diagnoses such as metabolic diseases, tumors, and Alzheimer's disease. This study thus aimed to investigate the effects of metformin treatment on the differentiation of osteoclasts and changes in AMPK mechanisms, which play an important role in regulating energy homeostasis, and mTOR, a highly conserved kinase that regulates autophagy. MATERIALS AND METHODS: Experimentation, including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, tartrate-resistant acid phosphate (TRAP) staining, pit formation assay, immunofluorescence, western blotting, and real-time polymerase chain reaction (PCR) was performed to investigate the effects of metformin on osteoclast differentiation. Additionally, to investigate its association with AMPK and pathways, the AMPK inhibitor compound C and mammalian targets of rapamycin (mTOR) activator leucine were used to examine the expression of osteoclast- or autophagy-related proteins, genes, and TRAP-positive cells. RESULTS: Metformin showed no cytotoxic effects on mouse osteoblastic cell lines (MC3T3-E1) and murine macrophage cell lines (RAW264.7) but did inhibit osteoclast differentiation. Furthermore, metformin was found to inhibit osteoclast differentiation through AMPK activation and mTOR inhibition. In turn, AMPK inhibition using compound C promoted osteoclast differentiation, and mTOR activation using leucine inhibited autophagy and osteoclast differentiation. CONCLUSIONS: Metformin activates the AMPK pathway while functioning as an activator of mTOR, thereby leading to the inhibition of autophagy and osteoclast differentiation.

Allopurinol-induced aplastic anemia in a patient with chronic kidney disease.

Aplastic anemia is a rare complication of allopurinol use. We report an unusual case of aplastic anemia associated with allopurinol therapy for hyperuricemia in a patient with chronic kidney disease. A 37-year-old female patient diagnosed with Stage III chronic kidney disease was admitted with pancytopenia. She had a history of taking allopurinol for 5 months. Her bone marrow showed extremely decreased cellularity (< 20%) and there was no malignant cell infiltration. She was free of infections, including parvovirus B19, cytomegalovirus and Epstein-Barr virus. These results suggested a diagnosis of aplastic anemia. Allopurinol was discontinued immediately and treatment with blood transfusions and prednisolone was begun. After 6 months, the bone marrow cellularity improved to approximately 70%. Recently, it was suggested that decreased activity of multidrug resistance P-glycoprotein may play a role in acquired aplastic anemia. So we measured the inhibitory effect of allopurinol and oxypurinol on P-glycoprotein activity. But neither allopurinol nor oxypurinol inhibited P-glycoprotein activity.

Utilization of house fly-maggots, a feed supplement in the production of broiler chickens.

Recent studies have suggested the utilization of maggots as a feed supplement forenhanced broiler performance. Maggots, which are a major dietary source of protein, appear during the biodegradation of chicken droppings using house flies. The objective ofthe present study was to investigate the effect of maggot supplementation on the meat quality and growth performance of broiler chickens. A total of 600 one-day-old male commercial broiler chicks (Ross) were randomly assigned into 5 treatment groups consisting of 40 replicates of 3 birds. The birds were fed either a basal diet or the basal diet supplemented with 5.0, 10.0, 15.0 and 20.0% maggots. Overall, broiler chicken performance was influenced by the optimal amino acid profile; high protein (63.99%) and essential amino acid content (29.46%), or high protein digestibility (98.50%) of the maggots. Maggot supplementation caused linear increases in live weight gain but not the feed conversion ratio. The diets of 10 and 15% maggots was the most efficient in terms of average weight gain forthe 4-5 week old broiler chickens (p<0.05). It also significantly increased dressing percentage, breast muscle, and thigh muscle (p<0.05). No differences were observed forliver abdominalfat, or meat color, and the crude protein contents of breast muscle were constant. However, in the maggot-fed broilers, breast muscle lysine and tryptophan levels increased significantly as compared to the birds fed the basal diet (p<0.05). These results indicate that feeding diets containing 10 to 15% maggots in chicken dropping after biodegradation can improve the carcass quality and growth performance of broiler chickens.

A case of disseminated Nocardia farcinica diagnosed through DNA sequencing in a kidney transplantation patient.

Nocardia is a rare gram-positive bacteria causing opportunistic infection, and belongs to the aerobic Actinomycetes group. As the mortality in the immunocompromised patients with nocardiosis is high, early diagnosis and treatment is very important. However, clinical manifestations of infection caused by Nocardia are very variable and early diagnosis is limited by the difficulty in obtaining specimens and its isolation. Rapid diagnosis of Nocardia infection may allow for earlier effective therapy, thus improving patient outcome. We report a case of Nocardia farcinica diagnosed by DNA sequencing through blood culture in a renal transplant recipient with severe pneumonia and multiple brain abscesses.

Long term disease-free survival in acute leukemia patients recovering with increased gammadelta T cells after partially mismatched related donor bone marrow transplantation.

Allogeneic stem cell transplantation (ASCT) has improved leukemia-free survival (LFS) in many but not all patients with acute leukemia. This is an eight-year follow-up to our previous study showing a survival advantage to patients with an increased gammadelta T cells following ASCT. gammadelta T cell levels were collected prospectively in 153 patients (acute lymphoblastic leukemia (ALL) n = 77; acute myelogenous leukemia (AML) n = 76) undergoing partially mismatched related donor ASCT. Median age was 22 years (1-59), and 62% of the patients were in relapse at transplant. Patient-donor human leukocyte antigen (HLA) disparity of three antigens was 37% in the graft-versus-host disease (GvHD) and 29% in the rejection directions. All patients received a partially T cell-depleted graft using T10B9 (n = 46) or OKT3 (n = 107). Five years LFS and overall survival (OS) of patients with increased gammadelta compared to those with normal/decreased numbers were 54.4 vs 19.1%; P < 0.0003, and 70.8 vs 19.6% P < 0.0001, respectively, with no difference in GvHD (P = 0.96). In a Cox multivariate analysis, normal/decreased gammadelta (hazard ratio (HR) 4.26, P = 0.0002) and sex mismatch (HR 1.45 P=0.049) were associated with inferior LFS. In conclusion, gammadelta T cells may facilitate a graft-versus-leukemia (GvL) effect, without causing GvHD. Further evaluations of this effect may lead to specific immunotherapy for patients with refractory leukemia.

MR1-restricted mucosal-associated invariant T (MAIT) cells respond to mycobacterial vaccination and infection in nonhuman primates.

Studies on mucosal-associated invariant T cells (MAITs) in nonhuman primates (NHP), a physiologically relevant model of human immunity, are handicapped due to a lack of macaque MAIT-specific reagents. Here we show that while MR1 ligand-contact residues are conserved between human and multiple NHP species, three T-cell receptor contact-residue mutations in NHP MR1 diminish binding of human MR1 tetramers to macaque MAITs. Construction of naturally loaded macaque MR1 tetramers facilitated identification and characterization of macaque MR1-binding ligands and MAITs, both of which mirrored their human counterparts. Using the macaque MR1 tetramer we show that NHP MAITs activated in vivo in response to both Bacillus Calmette-Guerin vaccination and Mycobacterium tuberculosis infection. These results demonstrate that NHP and human MR1 and MAITs function analogously, and establish a preclinical animal model to test MAIT-targeted vaccines and therapeutics for human infectious and autoimmune disease.

Increase of transcription factor EB (TFEB) and lysosomes in rat DRG neurons and their transportation to the central nerve terminal in dorsal horn after nerve injury.

In the spinal dorsal horn (DH), nerve injury activates microglia and induces neuropathic pain. Several studies clarified an involvement of adenosine triphosphate (ATP) in the microglial activation. However, the origin of ATP together with the release mechanism is unclear. Recent in vitro study revealed that an ATP marker, quinacrine, in lysosomes was released from neurite terminal of dorsal root ganglion (DRG) neurons to extracellular space via lysosomal exocytosis. Here, we demonstrate a possibility that the lysosomal ingredient including ATP released from DRG neurons by lysosomal-exocytosis is an additional source of the glial activation in DH after nerve injury. After rat L5 spinal nerve ligation (SNL), mRNA for transcription factor EB (TFEB), a transcription factor controlling lysosomal activation and exocytosis, was induced in the DRG. Simultaneously both lysosomal protein, LAMP1- and vesicular nuclear transporter (VNUT)-positive vesicles were increased in L5 DRG neurons and ipsilateral DH. The quinacrine staining in DH was increased and co-localized with LAMP1 immunoreactivity after nerve injury. In DH, LAMP1-positive vesicles were also co-localized with a peripheral nerve marker, Isolectin B4 (IB4) lectin. Injection of the adenovirus encoding mCherry-LAMP1 into DRG showed that mCherry-positive lysosomes are transported to the central nerve terminal in DH. These findings suggest that activation of lysosome synthesis including ATP packaging in DRG, the central transportation of the lysosome, and subsequent its exocytosis from the central nerve terminal of DRG neurons in response to nerve injury could be a partial mechanism for activation of microglia in DH. This lysosome-mediated microglia activation mechanism may provide another clue to control nociception and pain.

ROS1 Kinase Inhibitors for Molecular-Targeted Therapies.

ROS1 is a pivotal transmembrane receptor protein tyrosine kinase which regulates several cellular processes like apoptosis, survival, differentiation, proliferation, cell migration, and transformation. There is increasing evidence supporting that ROS1 plays an important role in different malignancies including glioblastoma, colorectal cancer, gastric adenocarcinoma, inflammatory myofibroblastic tumor, ovarian cancer, angiosarcoma, and non small cell lung cancer; thus, ROS1 has become a potential drug discovery target. ROS1 shares about 49% sequence homology with ALK primary structure; therefore, wide range of ALK kinase inhibitors have shown in vitro inhibitory activity against ROS1 kinase. After Crizotinib approval by FDA for the management of ALK-rearranged lung cancer, ROS1-positive tumors have been focused. Although significant advancements have been achieved in understanding ROS1 function and its signaling pathways plus recent discovery of small molecules modulating ROS1 protein, a vital need of medicinal chemistry efforts is still required to produce selective and potent ROS1 inhibitors as an important therapeutic strategy for different human malignancies. This review focuses on the current knowledge about different scaffolds targeting ROS1 rearrangements, methods to synthesis, and some biological data about the most potent compounds that have delivered various scaffold structures.

Vitamin D receptor polymorphism is associated with psoriasis.

Vitamin D receptor is a trans-acting transcriptional factor that mediates 1alpha,25-dihydroxyvitamin D3 action in the regulation of target gene expression. Recent studies have shown that clinical response of psoriasis to 1alpha,25-dihydroxyvitamin D3 is correlated with the vitamin D receptor mRNA expression level, which may be influenced by the genotype of the vitamin D receptor. In this study, we have explored a possible association between psoriasis and the polymorphism in the gene encoding the vitamin D receptor. We examined the allelic frequencies of the vitamin D receptor in psoriasis patients (n = 104) and in healthy controls (n = 104) by analyzing the restriction pattern of the polymerase chain reaction products. A significant increase in the frequency of the A allele (absence of the restriction site at intron 8) by ApaI restriction fragment length polymorphism was observed in psoriasis patients compared with that of the control group, and the tendency was more accentuated in early onset psoriasis. Odds ratios (95% confidence interval) for psoriasis of AA and Aa genotypes were 5.0 (1.3-19.1) and 2.4 (1.3-4.3), and odds ratios for early onset of AA and Aa genotypes were 6.4 (1.6-25.0) and 3.1 (1.7-5.9), respectively. Allele frequencies for A and a alleles were 0.317 and 0.683 in the psoriasis group and 0.168 and 0.832 in the control group (p = 0.001). A significant association between vitamin D receptor genotypes and the mean age at onset was observed (p < 0.05). Our findings suggest that allelic variance in the vitamin D receptor gene itself or other genes in linkage disequilibrium with this gene, could predispose to the development of psoriasis.

Promoter sequences of two homologous pectin esterase genes from Chinese cabbage (Brassica campestris L. ssp. pekinensis) and pollen-specific expression of the GUS gene driven by a promoter in tobacco plants.

The promoter regions of two genomic clones, GBAN215-6 and GBAN215-12 from Chinese cabbage (Brassica campestris L. ssp. pekinensis), were sequenced. The nucleotide sequences of their promoter regions were compared with that of the Bp19 pollen-specific gene of Brassca napus. High nucleotide sequence homologies were observed among these three genes in the region between 210 bp upstream and the putative transcription start site. A sequence motif TGTGGTG, which is similar to that of the PB core motif (TGTGGTT) of two tomato pollen-specific genes, LAT52 and LAT56, was present in these two cloned genes. To determine regulatory sequences responsible for the anther-specific expression of the gene BAN215-6, two recombinant plasmids, pBPE3 (-274- + 109) and pBPE4 (-816- + 109) containing different lengths of the promoter fused with the GUS gene, were constructed and introduced into tobacco plants by Agrobacterium-mediated transformation. The result showed that the 383 bp (-274- + 109) of the BAN215-6 promoter region was sufficient for the anther-specific expression of the GUS gene. The GUS expression in a tobacco plants transformed with these constructs was first detected in uninucleate microspores and persisted at in vitro germinated pollen tubes. The expression level was increased during anther development, reaching the highest level in mature pollens.

Szygium aromaticum (L.) Merr. Et Perry (Myrtaceae) flower bud induces apoptosis of p815 mastocytoma cell line.

This study was conducted to investigate SAFB-induced apoptosis of mast cells as it pertains to both its basic drug mechanism and the potential therapeutics of the pathologic conditions accompanying mast cell proliferation. SAFB induced many apoptotic manifestations as evidenced by changes in cell morphology, generation of DNA fragmentation, activation of caspase 3, and DNA hypoploidy. The reduction of mitochondrial membrane potential and the release of cytochrome c to cytosol were also demonstrated. However, reduction of mitochondrial membrane potential and cytochrome c release were not prevented by caspase inhibitor zVAD-fmk or PTP blockers such as bongkrekic acid and cyclosporin A. Expression levels of Bcl-2 and Fas remained unchanged following SAFB treatment. This results suggest that the clinical effect of SAFB may depend on the pharmacological mechanism regulating the demise of mast cells.

Concurrence of replicative senescence and elevated expression of p16(INK4A) with subculture-induced but not calcium-induced differentiation in normal human oral keratinocytes.

Primary normal human oral keratinocytes (NHOKs) undergo differentiation in the presence of calcium concentrations higher than 0.15 mM in vitro, which is useful in investigating the mechanisms involved in the differentiation of epithelial cells. Serial subculture of NHOKs to the postmitotic stage also induces terminal differentiation. However, the detailed mechanisms of both differentiation processes remain substantially unknown. To investigate the molecular differences in these processes, NHOKs were induced to differentiate by exposure to 1.2 mM of calcium and by serial subculture to the postmitotic stage. To study whether the cells were induced to differentiate and to undergo replicative senescence, the amount of cellular involucrin and the expression of senescence-associated beta-galactosidase (SA-beta-gal) were measured respectively. The expression of replicative senescence-associated genes and the activity of telomerase from the differentiated cells were also determined. Both calcium treatment and serial subculture to the postmitotic stage notably elevated the cellular involucrin. The percentage of SA-beta-gal-positive cells was significantly elevated by the continued subculture, but such changes were not observed in keratinocytes exposed to calcium. The concentration of cellular p16(INK4A) protein was progressively increased by the continued subculture but was not changed by calcium treatment. On the other hand, the concentrations of cellular p53 were similar in both differentiation processes. However, telomerase activity was lost in NHOKs that had undergone differentiation by both calcium treatment and serial subculture. The results indicate that calcium-induced differentiation of NHOKs has similar characteristics to their serial subculture-induced differentiation, but that the differentiation processes are not identical, because calcium-induced differentiation does not concur with either replicative senescence or the gradually increased concentration of p16(INK4A).

Effect of phosphatidylcholine on the alpha-lactalbumin-induced fusion of vesicles.

Previous studies on alpha-lactalbumin induced fusion of phosphatidylserine/phosphatidylethanolamine vesicles are extended to vesicles composed of various combinations of phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine and cardiolipin. It was found that inclusion of phosphatidylcholine in the vesicles results in a depression of fusion. This depression of fusion appears to be caused by a reduction in the amount of irreversibly bound alpha-lactalbumin to vesicles containing phosphatidylcholine. It is suggested that in this system fusion is dependent upon the extent by which a particular protein segment penetrates the bilayer.

Factors influencing psoriasis: an analysis based upon the extent of involvement and clinical type.

A variety of external stimuli are accepted as important in modifying the severity of psoriasis. We sought to determine whether there is any difference in the influence of external factors on psoriasis in relation to extent of involvement or clinical type. A total of 870 psoriasis patients seen between 1982 and 1995 were categorized as mild, moderate, or severe on the basis of extent of the disease, and as guttate, nummular/plaque, or exfoliative/generalized pustular according to clinical type. We then performed a questionnaire survey concerning the influence of external factors such as seasonal changes, sunlight, stress, and pregnancy. These data sets were combined and analysed. The majority of patients stated favorable effects of summer, sunlight, and pregnancy and adverse effects of winter and stress. A statistically significant correlation was noted between the extent of psoriasis and the proportion of patients stating that their disease worsened at times of psychological stress (p < 0.01). We confirmed that psoriasis patients with more extensive involvement experience greater fluctuations in their condition, notice these changes, and therefore relate them to psychological stress.

Disseminated superficial porokeratosis in a patient with chronic liver disease.

A 55-year-old male suffering from liver cirrhosis presented with diffuse annular hyperkeratotic papules of abrupt onset on the trunk and extremities. Histopathologic examination revealed cornoid lamella and eosinophilic spongiosis. He did not receive any medications other than cephalosporin for spontaneous bacterial peritonitis. A review of the literature revealed that three cases developed porokeratosis when their liver function declined and that, in one case, the porokeratosis disappeared spontaneously with liver transplantation. Although the precise mechanism is unclear, there is evidence demonstrating immunoincompetence in cirrhosis. Even though we did not perform immunologic studies or exclude the possibility of drug-induced porokeratosis in our case, it is conceivable that porokeratosis can be triggered by immunosuppression due to liver cirrhosis per se.

Characterization of early and late onset psoriasis in the Korean population.

It has been proposed that two types of psoriasis can be characterized based upon age of onset. The purpose of our study was to investigate the characteristics of early and late onset psoriasis in the Korean population. A total of 986 psoriasis patients were included in this study, and the age of onset frequency proved to be bimodal. Family history in the first-degree relatives was significantly higher in the early onset group (< 40 years old) when compared with the late onset group (> or = 40 years old). A series of statistical analyses concerning the correlation between the extent of involvement and age of onset showed that earlier onset is related to more extensive involvement. A questionnaire survey concerning the influence of various external factors upon their psoriasis was given to a subgroup of 800 psoriasis patients. Multiple logistic regression analysis, controlled for confounding factors such as current age, sex and extent of involvement, revealed that early onset psoriasis patients showed significantly increased tendencies to worsen at times of psychological stress and in winter, and to improve in summer, compared with late onset psoriasis patients. In conclusion, distribution of the age of onset revealed two peaks in Korean psoriasis patients, and psoriasis with an onset prior to the age of 40 years was associated with increased inheritability, greater susceptibility to seasonal changes and more psychological stress than psoriasis with later onset.

Fumigant toxicity of volatile natural products from Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae (L).

The fumigant toxicity of various volatile constituents of essential oils extracted from sixteen Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae L (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in the essential oil from Mentha arvensis L. var piperascens (LC50 = 45.5 microliters litre-1 air). GC-MS analysis of essential oil from M arvensis showed it to be rich in menthol (63.2%), menthone (13.1%) and limonene (1.5%), followed in abundance by beta-pinene (0.7%), alpha-pinene (0.6%) and linalool (0.2%). Treatment of S oryzae with each of these terpenes showed menthone to be most active (LC50 = 12.7 microliters litre-1 air) followed by linalool (LC50 = 39.2 microliters litre-1 air) and alpha-pinene (LC50 = 54.9 microliters litre-1 air). Studies on inhibition of acetylcholinesterase activity of S oryzae showed menthone to have a nine-fold lower inhibitory effect than menthol, despite menthone being 8.1-fold more toxic than menthol to the rice weevil. Different modes of toxicity of these monoterpenes towards S oryzae are discussed.

Staurosporine analogues from microbial and synthetic sources and their biological activities.

In 1977 an unknown natural product was isolated from Streptomyces staurosporeus by Omura et al. during a search for new alkaloids present in actinomycetes and was given the name AM-2282. Later, the structure of AM-2282 was elucidated by single crystal X-ray analysis and renamed as staurosporine. It has been published that staurosporine and its analogues display strong inhibitory effect against a variety of kinases and a number of biological properties such as antifungal, antibacterial, and immunosuppressive activities. Despite strong inhibitory activity of staurosporine, a very high level of cross-reactivity makes it impossible to use staurosporine as a therapeutic agent. In the course of searching for other staurosporine-related compounds, a number of staurosporine analogues have been isolated from different microorganisms. In addition, a number of staurosporine analogues have been synthesized to improve the poor selectivity and target specificity of staurosporine which limited its clinical effectiveness. The review addresses staurosporine analogues from both microbial and synthetic sources and their biological activities.

Thyroid transcription factor 1, a homeodomain containing transcription factor, contributes to regulating periodic oscillations in GnRH gene expression.

Thyroid transcription factor 1 (TTF1), a member of the Nkx family of transcription factors required for basal forebrain morphogenesis, functions in the postnatal hypothalamus as a transcriptional regulator of genes encoding neuromodulators and hypophysiotrophic peptides. One of these peptides is gonadotrophin-releasing hormone (GnRH). In the present study, we show that Ttf1 mRNA abundance varies in a diurnal and melatonin-dependent fashion in the preoptic area of the rat, with maximal Ttf1 expression attained during the dark phase of the light/dark cycle, preceding the nocturnal peak in GnRH mRNA content. GnRH promoter activity oscillates in a circadian manner in GT1-7 cells, and this pattern is enhanced by TTF1 and blunted by small interfering RNA-mediated Ttf1 gene silencing. TTF1 transactivates GnRH transcription by binding to two sites in the GnRH promoter. Rat GnRH neurones in situ contain key proteins components of the positive (BMAL1, CLOCK) and negative (PER1) limbs of the circadian oscillator, and these proteins repress Ttf1 promoter activity in vitro. By contrast, Ttf1 transcription is activated by CRY1, a clock component required for circadian rhythmicity. In turn, TTF1 represses transcription of Rev-erbα, a heme receptor that controls circadian transcription within the positive limb of the circadian oscillator. These findings suggest that TTF1 is a component of the molecular machinery controlling circadian oscillations in GnRH gene transcription.