Conserved transcription factors promote cell fate stability and restrict reprogramming potential in differentiated cells

Defining the mechanisms safeguarding cell fate identity in differentiated cells is crucial to improve 1) - our understanding of how differentiation is maintained in healthy tissues or altered in a disease state, and 2) - our ability to use cell fate reprogramming for regenerative purposes. Here, using a genome-wide transcription factor screen followed by validation steps in a variety of reprogramming assays (cardiac, neural and iPSC in fibroblasts and endothelial cells), we identified a set of four transcription factors (ATF7IP, JUNB, SP7, and ZNF207 [AJSZ]) that robustly opposes cell fate reprogramming in both lineage and cell type independent manners. Mechanistically, our integrated multi-omics approach (ChIP, ATAC and RNA-seq) revealed that AJSZ oppose cell fate reprogramming by 1) - maintaining chromatin enriched for reprogramming TF motifs in a closed state and 2) - downregulating genes required for reprogramming. Finally, KD of AJSZ in combination with MGT overexpression, significantly reduced scar size and improved heart function by 50%, as compared to MGT alone post-myocardial infarction. Collectively, our study suggests that inhibition of barrier to reprogramming mechanisms represents a promising therapeutic avenue to improve adult organ function post-injury.

Cognitive Models in Cybersecurity: Learning From Expert Analysts and Predicting Attacker Behavior

Cybersecurity stands to benefit greatly from models able to generate predictions of attacker and defender behavior. On the defender side, there is promising research suggesting that Symbolic Deep Learning (SDL) may be employed to automatically construct cognitive models of expert behavior based on small samples of expert decisions. Such models could then be employed to provide decision support for non-expert users in the form of explainable expert-based suggestions. On the attacker side, there is promising research suggesting that model-tracing with dynamic parameter fitting may be used to automatically construct models during live attack scenarios, and to predict individual attacker preferences. Predicted attacker preferences could then be exploited for mitigating risk of successful attacks. In this paper we examine how these two cognitive modeling approaches may be useful for cybersecurity professionals via two human experiments. In the first experiment participants play the role of cyber analysts performing a task based on Intrusion Detection System alert elevation. Experiment results and analysis reveal that SDL can help to reduce missed threats by 25%. In the second experiment participants play the role of attackers picking among four attack strategies. Experiment results and analysis reveal that model-tracing with dynamic parameter fitting can be used to predict (and exploit) most attackers' preferences 40-70% of the time. We conclude that studies and models of human cognition are highly valuable for advancing cybersecurity.

Model system identification of novel congenital heart disease gene candidates: focus on RPL13

Genetics is a significant factor contributing to congenital heart disease (CHD), but our understanding of the genetic players and networks involved in CHD pathogenesis is limited. Here, we searched for de novo copy number variations (CNVs) in a cohort of 167 CHD patients to identify DNA segments containing potential pathogenic genes. Our search focused on new candidate disease genes within 19 deleted de novo CNVs, which did not cover known CHD genes. For this study, we developed an integrated high-throughput phenotypical platform to probe for defects in cardiogenesis and cardiac output in human induced pluripotent stem cell (iPSC)-derived multipotent cardiac progenitor (MCPs) cells and, in parallel, in the Drosophila in vivo heart model. Notably, knockdown (KD) in MCPs of RPL13, a ribosomal gene and SON, an RNA splicing cofactor, reduced proliferation and differentiation of cardiomyocytes, while increasing fibroblasts. In the fly, heart-specific RpL13 KD, predominantly at embryonic stages, resulted in a striking 'no heart' phenotype. KD of Son and Pdss2, among others, caused structural and functional defects, including reduced or abolished contractility, respectively. In summary, using a combination of human genetics and cardiac model systems, we identified new genes as candidates for causing human CHD, with particular emphasis on ribosomal genes, such as RPL13. This powerful, novel approach of combining cardiac phenotyping in human MCPs and in the in vivo Drosophila heart at high throughput will allow for testing large numbers of CHD candidates, based on patient genomic data, and for building upon existing genetic networks involved in heart development and disease.

Generation of First Heart Field-like Cardiac Progenitors and Ventricular-like Cardiomyocytes from Human Pluripotent Stem Cells

The generation of large amounts of functional human pluripotent stem cells-derived cardiac progenitors and cardiomyocytes of defined heart field origin is a pre-requisite for cell-based cardiac therapies and disease modeling. We have recently shown that Id genes are both necessary and sufficient to specify first heart field progenitors during vertebrate development. This differentiation protocol leverages these findings and uses Id1 overexpression in combination with Activin A as potent specifying cues to produce first heart field-like (FHF-L) progenitors. Importantly, resulting progenitors efficiently differentiate (~70-90%) into ventricular-like cardiomyocytes. Here we describe a detailed method to 1) generate Id1-overexpressing hPSCs and 2) differentiate scalable quantities of cryopreservable FHF-L progenitors and ventricular-like cardiomyocytes.

An Automated Platform for Assessment of Congenital and Drug-Induced Arrhythmia with hiPSC-Derived Cardiomyocytes

The ability to produce unlimited numbers of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) harboring disease and patient-specific gene variants creates a new paradigm for modeling congenital heart diseases (CHDs) and predicting proarrhythmic liabilities of drug candidates. However, a major roadblock to implementing hiPSC-CM technology in drug discovery is that conventional methods for monitoring action potential (AP) kinetics and arrhythmia phenotypes in vitro have been too costly or technically challenging to execute in high throughput. Herein, we describe the first large-scale, fully automated and statistically robust analysis of AP kinetics and drug-induced proarrhythmia in hiPSC-CMs. The platform combines the optical recording of a small molecule fluorescent voltage sensing probe (VoltageFluor2.1.Cl), an automated high throughput microscope and automated image analysis to rapidly generate physiological measurements of cardiomyocytes (CMs). The technique can be readily adapted on any high content imager to study hiPSC-CM physiology and predict the proarrhythmic effects of drug candidates.

Id genes are essential for early heart formation

Deciphering the fundamental mechanisms controlling cardiac specification is critical for our understanding of how heart formation is initiated during embryonic development and for applying stem cell biology to regenerative medicine and disease modeling. Using systematic and unbiased functional screening approaches, we discovered that the Id family of helix-loop-helix proteins is both necessary and sufficient to direct cardiac mesoderm formation in frog embryos and human embryonic stem cells. Mechanistically, Id proteins specify cardiac cell fate by repressing two inhibitors of cardiogenic mesoderm formation-Tcf3 and Foxa2-and activating inducers Evx1, Grrp1, and Mesp1. Most importantly, CRISPR/Cas9-mediated ablation of the entire Id (Id1-4) family in mouse embryos leads to failure of anterior cardiac progenitor specification and the development of heartless embryos. Thus, Id proteins play a central and evolutionarily conserved role during heart formation and provide a novel means to efficiently produce cardiovascular progenitors for regenerative medicine and drug discovery applications.

Effects of Information Availability on Command-and-Control Decision Making: Performance, Trust, and Situation Awareness

OBJECTIVE

We investigated how increases in task-relevant information affect human decision-making performance, situation awareness (SA), and trust in a simulated command-and-control (C2) environment.

BACKGROUND

Increased information is often associated with an improvement of SA and decision-making performance in networked organizations. However, previous research suggests that increasing information without considering the task relevance and the presentation can impair performance.

METHOD

We used a simulated C2 task across two experiments. Experiment 1 varied the information volume provided to individual participants and measured the speed and accuracy of decision making for task performance. Experiment 2 varied information volume and information reliability provided to two participants acting in different roles and assessed decision-making performance, SA, and trust between the paired participants.

RESULTS

In both experiments, increased task-relevant information volume did not improve task performance. In Experiment 2, increased task-relevant information volume reduced self-reported SA and trust, and incorrect source reliability information led to poorer task performance and SA.

CONCLUSION

These results indicate that increasing the volume of information, even when it is accurate and task relevant, is not necessarily beneficial to decision-making performance. Moreover, it may even be detrimental to SA and trust among team members.

APPLICATION

Given the high volume of available and shared information and the safety-critical and time-sensitive nature of many decisions, these results have implications for training and system design in C2 domains. To avoid decrements to SA, interpersonal trust, and decision-making performance, information presentation within C2 systems must reflect human cognitive processing limits and capabilities.

Conducting polymer nanoparticles decorated with collagen mimetic peptides for collagen targeting

We report on the formation of conducting polymer nanoparticles (CPNs), stabilized by a collagen mimetic peptide (CMP)-polymer amphiphile. CPNs ranging from ∼15 to 40 nm were readily accessible upon modifying the amphiphile concentration. Surface presentation of CMPs on CPN precluded intra-/inter-particle trimerization, while preserving their ability to target collagen without pre-activation.

Neuroprotective effects of minocycline on double-stranded RNA-induced neurotoxicity in cultured cortical neurons

1. Minocycline, memantine,and glycoconjugate were assessed for their ability to protect cultured primary cortical neurons against double-stranded RNA-induced neurotoxicity. 2. Minocycline but not memantine or glycoconjugate protected cultured cells and warrants further investigation.

Removal of a nasal bone intraosseous venous malformation and primary reconstruction of the surgical defect using open rhinoplasty

Primary intraosseous venous malformations are rare benign tumors that account for approximately 1% of all primary osseous tumors. They are rarely found in the midface. The authors report a case of an intraosseous venous malformation in a 28-year-old woman who presented with a bony lesion in the nasal bone. Treatment involved surgical excision via open rhinoplasty. Histopathology indicated an intraosseous venous malformation. 16 months postoperatively, there was no evidence of recurrence, the functional and cosmetic results were good, and the patient was satisfied with the treatment outcome.

Phase II study of docetaxel and irinotecan combination chemotherapy in metastatic gastric carcinoma

The current treatment for metastatic gastric cancer (MGC) consists of cisplatin and/or fluorouracil (5-FU) based combination chemotherapy, but cisplatin-based regimens are associated with considerable toxicity. We evaluated the efficacy and safety of a noncisplatin-, non-5-FU-containing regimen, docetaxel/irinotecan in MGC. Chemo-naive patients with MGC received docetaxel (30 mg m(-2)) and irinotecan (70 mg m(-2)) on days 1 and 8 every 3 weeks. The 48 eligible patients (median age 56 years) received a median of four cycles of docetaxel/irinotecan (range 1-18). Of the 46 patients in whom efficacy could be evaluated, 21 showed a partial response (response rate=45.7%; 95% confidence interval (CI) 31.3-60.1%). At a median follow-up of 15.0 months, the median time to progression was 4.5 months (95% CI 3.8-5.2 months) and overall survival was 8.2 months (95% CI, 5.8-10.6 months). Grade 3/4 neutropenia developed in 57.4% of patients, and febrile neutropenia/neutropenic infection in 19.1%. Nonhaematological toxicities were moderate; grade 3/4 diarrhoea occurred in 19.1% of patients, however, was manageable by a dose reduction. There was one possible treatment-related death. In conclusion, weekly docetaxel/irinotecan is a promising outpatient regimen in MGC, with appropriate dose modification.

Analysis of particle laden flow and heat transfer in cascade and rocket nozzle

This paper presents results for the calculation of particle trajectories in a cascade and a rocket nozzle using a Lagrangian method. When the floating particles collide to the components, the component surface is damaged severely. The surface erosion rate is strongly dependent on a particle size, a particle impact angle and a surface material. For a compressor cascade, the particle impact rate increases proportionally with the flow inlet angle and the erosion rate on the pressure side surface of blade are related to the surface or coating materials. For a solid rocket nozzle, the particle free zone in the nozzle divergent section increases quickly with increasing particle size and the maximum heat transfer density occurs at the starting region of nozzle convergent section. The Al2O3 droplet breaks up around the nozzle throat due to the high velocity difference between the droplet and gas stream, resulting in the big change of particle free zone.

Metal content and biochemical analyses of a recombinant collagenase PrtV from Vibrio parahaemolyticus

PrtV is an extracellular metalloprotease of Vibrio parahaemolyticus and regarded as a collagenase. Inductively coupled plasma-optical emission spectrometry analysis indicated that the recombinant PrtV contains 1 mol of zinc per mol of the native enzyme. On the basis of a kinetic study using 2-furanacryloyl-Leu-Gly-Pro-Ala (FALGPA, the specific substrate for bacterial collagenase) as a substrate, it was suggested that metal ions may play a significant role in the binding and catalytic steps of the substrate. PrtV hydrolyzed type I, II, III, and IV collagens; however, it did not hydrolyze type V. In addition, the hydrolysis of native proteins and synthetic substrates revealed that PrtV possesses higher activity toward collagen and collagen-like sequences. The result of the thermal stability study indicated that PrtV was thermostable up to 40 C; at 50 C, stability gradually decreased. In addition, PrtV showed higher storage stability at -20 and 4 C, respectively, than at 25 C. Compared with collagenases from Clostridium histolyticum and Vibrio alginolyticus, PrtV was immunologically different and had no significant effect on the growth of CHO, HeLa, and Vero cells. Taken together, the results of the studies described in this paper advance our knowledge concerning the metal content and biochemical properties of PrtV.

Hereditary nonpolyposis colorectal cancer with gynecologic malignancies: report of two families in Taiwan

Hereditary nonpolyposis colon cancer (HNPCC), also known as Lynch syndrome, is characterized by germline and somatic mutations of DNA mismatch repair genes with dominant inheritance of site-specific colorectal cancer or colorectal cancer plus cancers of extracolonic sites. We describe two Taiwanese HNPCC families with members who had predominantly gynecologic malignancies. In one family, the 53-year-old proband was found to have five synchronous and metachronous tumors of the genitourinary system, which included endometrial adenocarcinoma, cervical squamous cell carcinoma, ureteral and bladder transitional cell carcinoma, and ovarian teratoma. Fourteen of her first- and second-degree relatives were victims of genitourinary and gastrointestinal malignancies. The other family was characterized by four sisters who developed endometrial adenocarcinomas at young ages (36-42 yr). Their father died of both stomach cancer and colon cancer at age 47. The diagnosis of HNPCC was confirmed in this family by genetic analysis. A heterozygous germline mutation (G5 to G6 frame-shift at 183-187) of the hMSH2 (human MutS homolog 2) gene was identified in white blood cells of all the affected family members. The frequent presentation of genitourinary cancers in HNPCC highlights the importance of family-history taking in patients with gynecologic cancers and a genetic diagnosis of HNPCC.

[Treating cicatricial baldness with scalp expanding and hair autografting]

OBJECTIVE

To investigate the effective method to treat cicatricial baldness.

METHODS

From 1993 to 1998, 21 cases with multi-region or great-dimensional cicatricial baldness were treated with scalp expanding and hair autografting. Among them, there were 17 males and 4 females, aged from 14 to 49 years old. The operation was divided into two stages, stage one meaned to embed the expander under the scalp and stage two meaned to sow the autogenous hair.

RESULTS

All cases, no matter what the position and area, were repaired successfully. The biggest dimension of repaired baldness was 340 cm2, one expander exposed and one failed in expanding after operation and be corrected immediately. The normal hair direction changed in two cases.

CONCLUSION

Combined use of scalp expanding and hair autografting is an effective method to treat multi-region or great dimensional cicarticial baldness.

Lindane (gamma-hexachlorocyclohexane) induces internal Ca2+ release and capacitative Ca2+ entry in Madin-Darby canine kidney cells

The effect of lindane (gamma-hexachlorocyclohexane), an organochlorine pesticide, on Ca2+ mobilization in Madin-Darby canine kidney cells was examined by fluorimetry using fura-2 as a Ca2+ indicator. Lindane (5-200 microM) increased [Ca2+]i concentration-dependently. The [Ca2+]i signal comprised an immediate initial rise followed by a persistent phase. Ca2+ removal inhibited the [Ca2+]i signal by reducing both the initial rise and the sustained phase. This implies lindane-triggered Ca2+ influx and Ca2+ release. In Ca2+ -free medium, 0.15 mM lindane increased [Ca2+]i after pretreatment with carbonylcyanide m-chlorophenylhydrazone (CCCP, 2 microM), a mitochondrial uncoupler, and two endoplasmic reticulum Ca2+ pump inhibitors, thapsigargin and cyclopiazonic acid. Conversely, pretreatment with lindane abolished CCCP- and thapsigargin-induced Ca2+ release. This suggests that 0.15 mM lindane released Ca2+ from the endoplasmic reticulum, mitochondria and other stores. La3+ (1 mM) partly inhibited 0.1 mM lindane-induced [Ca2+]i increase, confirming that lindane induced Ca2+ influx. Addition of 3 mM Ca2+ increased [Ca2+]i after pretreatment with 0.15 mM lindane for 750 sec. in Ca2+ -free medium, which indicates lindane-induced capacitative Ca2+ entry. Lindane (0.15 mM)-induced Ca2+ release was not reduced by inhibiting phospholipase C with 2 microM U73122, but was inhibited by 70% by the phospholipase A2 inhibitor aristolochic acid (40 microM).

Oral ciprofloxacin as antibacterial prophylaxis after allogeneic bone marrow transplantation: a reappraisal

The efficacy of ciprofloxacin as antibacterial prophylaxis for allogeneic bone marrow transplantation has been well documented, and it virtually eliminated bacteremias caused by gram-negative pathogens in early reports. Ciprofloxacin was therefore incorporated into the prophylactic antibiotic regimen during allogeneic bone marrow or peripheral blood stem cell transplantation at Veterans General Hospital, Kaohsiung from February 1997. In 12 consecutive patients receiving allogeneic bone marrow or peripheral blood stem cell transplantation, ciprofloxacin-resistant Escherichia coli bacteremia developed in three (25%). In addition to our data, increasing evidence suggests that the widespread use of a fluoroquinolone is associated with the emergence of resistant isolates as well as documented infections caused by these resistant strains. The incidence of Escherichia coli bacteremia in our transplant patients was 25%, which was similar to that in patients not receiving preventive therapy or in those receiving trimethoprim-sulfamethoxazole prophylaxis. The prophylactic efficacy of ciprofloxacin in allogeneic bone marrow transplant or peripheral blood stem cell transplant recipients should therefore be reassessed.

Impact on maternal parenting stress of receipt of genetic information regarding risk of diabetes in newborn infants

Our objective was to investigate whether notification of high-risk status for type 1 diabetes in newborn infants results in an increased maternal-parenting stress level when compared with notification of low-risk status for type 1 diabetes. Maternal parenting stress level was assessed at 5-7 weeks postpartum (baseline) and was reassessed 4-5 months after parents were informed of their newborn infants' genetic screening results (follow-up). Parenting stress level was measured using the total stress score (TSS) of the Parenting Stress Index/Short Form. The outcome variable, change in TSS, was calculated by subtracting the baseline TSS from the follow-up TSS. Demographic variables such as maternal race, maternal age, maternal education level, maternal marital status, child's birth order, and total family income were assessed through a structured phone interview at the time of baseline assessment. The risk factor of interest was the child's human leukocyte antigen (HLA) status for type 1 diabetes, i.e., whether child was at a high or moderate (combined into "high") genetic risk or at a low genetic risk for type 1 diabetes. A sample of 88 mothers (23 with a high-risk child and 65 with a low-risk child) was evaluated. Baseline median TSSs were 65 and 74 for mothers of low-risk infants and mothers of high-risk infants, respectively. Both groups' median TSS decreased between baseline and follow-up. No significant differences were found between change in TSS and maternal age, race, education level, marital status, total family income, or child's birth order. Although the median decrease in TSS was smaller in mothers with a high-risk child when compared with mothers of a low-risk child, this difference was not statistically significant. We did not find an association between newborn's HLA status and change in maternal TSS. The results of this study suggest that notification of high-risk status for type 1 diabetes in newborn infants may not result in an increased level of parenting stress among mothers.

Laparoscopic loop ligatures for bladder repair during laparoscopic surgery

In this paper, we report a case where a bladder perforation occurred during a laparoscopically assisted vaginal hysterectomy and was repaired by laparoscopic loop ligatures. This is the first case report of using the laparoscopic loop ligatures to close the bladder perforations. The loop ligature is an easy and quick procedure, which can be performed by most surgeons who take the time to learn the endoscopic suturing techniques.

Nesidioblastosis, myelodysplastic syndrome and nodular diabetic glomerulosclerosis in an elderly nondiabetic woman: an autopsy report

Nesidioblastosis as the cause of hyperinsulinaemic hypoglycaemia in an adult is rare. We report here an additional case of nesidioblastosis, which resulted in fatal hyperinsulinaemic hypoglycaemia in a 72-year-old woman with an underlying myelodysplastic syndrome. The diagnosis of nesidioblastosis was established only after post-mortem examination with a careful exclusion of minute insulinoma. To our surprise, the renal pathology disclosed typical diabetic nodular glomerulosclerosis in the same patient who had no previous history of diabetes mellitus (DM). Nesidioblastosis has been reported to cause 'reversal' of Type 1 DM and insulinoma causing 'reversal' of Type 2 disease. We therefore hypothesize that our patient might have had an undiagnosed DM in the past, which resulted in the typical diabetic nodular glomerulosclerosis. The nesidioblastosis caused a 'reversal' of DM and even the ultimate development of hyperinsulinaemic hypoglycaemia.

HPV-associated cervical cancers show frequent allelic loss at 3p14 but no apparent aberration of FHIT mRNA

The genetic aberration involved in the loss of heterozygosity (LOH) at 3p14 has recently been attributed to the disruption of the FHIT gene in many cancers. This study analyzed HPV DNA and allelic status of 5 microsatellite markers spaning 3p13-3p25 in 57 cases of cervical cancer. With no homozygous deletion found in any case, a 39% overall frequency of LOH was noted. The presence of tumorigenic HPV DNA (91%) did not correlate with the allelic loss at any marker, including THRB (3p22-24) and D3S1228 (3p14) which were found with high LOH rates of 43% (12/28) and 37% (11/30), respectively. Further analysis of FHIT mRNA in 29 cancers by reverse transcription (RT)-PCR showed a full-length transcript in all cases. However, additional minor transcripts were occasionally observed in cancer tissues (9/29) as well as in normal tissues (12/31) by nested PCR of the RT products. Sequence analysis of these transcripts showed exclusive internal exon deletions, suggesting a source of minor splicing variants. No apparent mutation of the mRNA sequences was found in 8 transcripts examined, except for a silent polymorphism and a site of alternative splicing. The results suggest that, although frequently reported to be abrogated in several cancers, the mRNA of FHIT remains intact in cervical cancer. Other genes closely linked to FHIT may be responsible for frequent LOH at 3p14 observed in cervical cancer.

[Applied anatomic study of the posterior interosseous artery in forearm]

The posterior interosseous artery (PIA) is the nutritive artery of the dorsal forearm flap. This article describes the dissection study for PIA in 40 cases. The results are as follows: 1. PIA is classified into different types; 2. the external diameter of PIA at the inferior margin of the supinator, the length of PIA and the distance between the artery and external epicondyle of the humerus are described; 3. the course of the artery and its neighboring structures are defined. The above study provides the foundation of designing of the posterior forearm pedicled flap in the repair of defects situated on the forearm and hand.

An angiogenic factor from human bladder cancer: the investigation of purification and biological activities

An angiogenic factor from human transitional cell cancer of bladder has been purified by protein extraction, cation exchange chromatography, gel filtration high-performance liquid chromatography (GE-HPLC) and reversed-phase high-performance liquid chromatography (RP-HPLC). The purified substance was named bladder cancer angiogenic factor (BCAF). Biological activity of the BCAF was assessed by the method of chick embryo chorioallantoic membrane (CAM) assay and 3H-TdR incorporation into DNA in Balb/C 3T3 cells. The BCAF displayed the potent activities of neovascularization in CAM and DNA synthesis in Balb/C 3T3 cells. The ultrastructural features of blood vessels induced by the BCAF were similar to the blood vessels in tumors. The BCAF contained a protein with an approximate molecular weight of 15,000 D which was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining. Amino acid compositions of the BCAF were also analysed by acid hydrolysis.

Immunohistochemical detection of Newcastle disease virus in chickens

An immunoperoxidase histochemical technique utilizing a monoclonal primary antibody was developed for detection of Newcastle disease virus (NDV) antigen in tissues from chickens. The technique was applied to trachea, lung, spleen, Harderian gland, and cecal tonsil harvested from specific-pathogen-free (SPF) chickens at 2, 5, 7, 10, and 14 days postinoculation (PI) with NDV, and to corresponding tissues from commercial broiler chickens representing 30 cases of spontaneous respiratory disease. Positive staining occurred in the cytoplasm of respiratory epithelial cells in the trachea or bronchi of NDV-inoculated SPF chickens at 5 and 7 days PI. Staining also occurred in the respiratory epithelium of the trachea and bronchi of commercial broilers from seven of 30 cases of spontaneous respiratory disease. These results indicate that the immunoperoxidase technique has value as a rapid diagnostic test for Newcastle disease.

Seasonal variation in hepatic binding of estrogen in the turtle, Chrysemys picta

The present study describes the seasonal changes of the estrogen receptor (ER) system in the liver of the turtle, Chrysemys picta. [3H]Estradiol ([3H]E2) binding capacities and affinities of liver cytosols and nuclear extracts were measured with established procedures and analyzed by Scatchard plots. Our data revealed significant seasonal variations in both receptor content and the ER's affinity for [3H]E2 in the liver of the turtle. Nuclear ER content remained at a fairly stable level of 70 fmol/g tissue throughout the year, but exhibited two sharp increases in the months of May and October, attaining values of approximately 150 fmol/g tissue. These rises in nuclear ER content coincided temporally with the two peaks of vitellogenin accumulation and estrogen surge in the annual cycle previously reported for the female turtle. Cytosolic ER level in the liver exhibited a much more complex pattern. It fluctuated with a much wider range of 80 to 250 fmol/g tissue. Right after oviposition in July, it declined to its lowest value of 80 +/- 9 fmol/g tissue but gradually increased to 160 +/- 15 fmol/g tissue in September and remained at this medium range for the remaining of the fall season but rose sharply again to the highest value of the year in December, reaching a value of 270 +/- 7 fmol/g tissue. In the following winter months, cytosolic ER level declined until March before it rebounded to a second peak value of 242 +/- 6 fmol/g tissue in May.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of hypophysectomy and ovariectomy on hepatic estrogen receptor content in the turtle, Chrysemys picta

Estrogen receptor (ER) content in the cytosol and nuclear extract of the liver of adult female Chrysemys picta (control females) was measured in February, May, early June, and late June. Both cytosolic (C) and nuclear (N) hepatic ER content rose from low levels (C: 189 +/- 19; N: 52 +/- 23 fmol/g tissue) in February to significantly higher levels in May (C: 437 +/- 15; N: 124 +/- 25 fmol/g tissue) before declining to lower values in early June (C: 298 +/- 19; N: 118 +/- 20 fmol/g tissue) and late June (C: 274 +/- 22; N: 89 +/- 13 fmol/g tissue). This pattern of seasonal variation in hepatic ER content was also observed in gonadectomized females. Levels of hepatic ER content in ovariectomized turtles fluctuated in the same manner as those found in control females. However, elevations in hepatic ER contents were not observed in hypophysectomized females. Removal of the pituitary resulted in a drastic reduction in the May value (316 +/- 49 fmol/g tissue) of cytosolic ER content and a complete blockade in a rise of nuclear ER content in the liver of the turtle. Nuclear hepatic ER content remained at around 50 fmol/g tissue throughout the months of May and June. The two surgeries procedures caused no significant changes in the ER's affinity for estrogen. The present findings demonstrate a direct control of the pituitary over hepatic ER content which signifies important pituitary regulation of the vitellogenic process, at the liver level, during the spring reproductive season.

Identification of partial mutational sites in human mitochondrial DNA in the Chinese and its significance

A simple method for the identification of mutational sites in human mitochondrial DNA (mtDNA) was described. It was based on the human Cambridge sequence as a relative standard sequence and a single base pair substitution in mtDNA as a unique mutational form. The partial mutational sites can be determined using this method which was characterized by combining the restriction mapping with the analysis for the table of human mtDNA potential mutational sites with rapidity and simplicity. In the meanwhile, six mtDNA mutational sites found in Chinese population were identified by means of this method.

Nuclear acceptor sites for estrogen-receptor complexes in the liver of the turtle, Chrysemys picta. I. Sexual differences, species specificity and hormonal dependency

Hepatic estrogen receptors (ERs) of the female turtle, Chrysemys picta, when complexed with [3H]estradiol ([3H]E2), were shown to bind specifically to liver chromatin isolated from the same species. The binding of the [3H]E2 receptor complex to chromatin requires both the steroid ligand and the receptor protein. Maximal binding occurred within 60-70 min of incubation at 4 degrees C in a Tris buffer containing 0.1 M KCl. The binding of the [3H]E2 receptor complex to intact chromatin was saturable, whereas the binding to turtle or calf thymus DNA remained linear. Scatchard analyses revealed more estrogen receptor binding sites on hepatic chromatin isolated from female turtles than that prepared from the males (binding capacities: female chromatin = 67.9 +/- 6.8 fmol/mg DNA equivalent; male chromatin = 28.5 +/- 2.5 fmol/mg DNA equivalent). Furthermore, the [3H]E2 receptor complex was bound with a higher affinity to female chromatin than to male chromatin (association constants: female chromatin = 11.7 +/- 2.7 X 10(10) M-1; male chromatin = 2.5 +/- 0.7 X 10(10) M-1). In contrast to turtle hepatic [3H]E2 receptors, ERs in rat liver or mouse uterine cytosol exhibited little binding affinity for hepatic chromatin isolated from the turtle. Tissue specificity was demonstrated in the interaction of the [3H]E2 receptor complex and chromatin; high affinity, saturable binding of the [3H]E2 receptor complex was only observed on chromatin isolated from the liver but not on those prepared from the heart, kidney and muscle. A 3- to 4-fold increase in the number of hepatic chromatin [3H]E2 receptor binding sites was observed in 21-day ovariectomized or hypophysectomized female (capacities = 209.3 +/- 6.1 and 270 +/- 10.1 fmol/mg DNA equivalent, respectively). It is postulated that [3H]E2 receptor binding sites on the chromatin of intact females are partially 'masked', and removal of a gonadal and/or pituitary factor(s) unveils additional binding sites on the female chromatin. This paper is first to report the presence of high affinity, species- and tissue-specific acceptor sites on the liver chromatin of a reptilian species. The fact that the levels and properties of these acceptor sites are dependent on the sex and hormonal state of the animal suggests that they may play a role in the regulation of hepatic estrogen responsiveness and vitellogenesis in this species.

Mitochondrial DNA polymorphism in Chinese

Human mitochondrial DNA (mtDNA) restriction endonuclease fragment patterns were analyzed using placenta DNA isolated from 273 individuals representing four different nationalities, the Han, the Uygur, the Kazakh and the Hui populations. Thirty-eight fragment patterns (morphs) were observed with the enzyme ApaI, BamHI, EcoRI, HindIII, HinfI, HhaI, HapII, KpnI, Mbol, PstI, PvuII, SacI, ScaL and XhoI. Fourteen new morphs, including some only existing in individual racial and national populations were observed, which indicates that there is a significant difference in the distribution of mtDNA morphs among various national and racial populations. By comparison with the mtDNA sequences in primate species, some mtDNA ancestral morphs were found to be retained in Oriental population today. This result provided indirect evidence that Asia may be one of the human original sources. Genetic distances among four national populations computed and employed in construction of an average linkage tree suggested that the Uygur and the Kazakh populations combined to form a branch at first, then the Han and the Hui came together to form another one, and at last, these two branches converged into a stem. Again, it was found that the internal variation within the Uygur and the Kazakh populations was greater than that within the Han and the Hui populations. These results showed a relationship among the four different national populations in China based on the molecular level.