[Directed differentiation of human induced pluripotent stem cells into midbrain]

OBJECTIVE

To establish an efficient protocol for directed differentiation of human induced pluripotent stem cells (hiPSCs) into functional midbrain dopaminergic progenitor cells (DAPs) in vitro.

METHODS

hiPSCs were induced to differentiate into DAPs in two developmental stages. In the first stage (the first 13 days), hiPSCs were induced into intermediate cells morphologically similar to primitive neuroepithelial cells (NECs) in neural induction medium containing a combination of small molecule compounds. In the second stage, the intermediate cells were further induced in neural differentiation medium until day 28 to obtain DAPs. After CM-DiI staining, the induced DAPs were stereotactically transplanted into the right medial forebrain bundle (MFB) of rat models of Parkinson's disease (PD). Eight weeks after transplantation, the motor behaviors of PD rats was evaluated. Immunofluorescence assay of brain sections of the rats was performed at 2 weeks after transplantation to observe the survival, migration and differentiation of the transplanted cells in the host brain microenvironment.

RESULTS

hiPSCs passaged stably on Matrigel showed a normal diploid karyotype, expressed the pluripotency markers OCT4, SOX2, and Nanog, and were positive for alkaline phosphatase. The primitive neuroepithelial cells obtained on day 13 formed dense cell colonies in the form of neural rosettes and expressed the neuroepithelial markers (SOX2, Nestin, and PAX6, 91.3%-92.8%). The DAPs on day 28 highly expressed the specific markers (TH, FOXA2, LMX1A and NURR1, 93.3-96.7%). In rat models of PD, the hiPSCs-DAPs survived and differentiated into TH⁺, FOXA2⁺ and Tuj1⁺ neurons at 2 weeks after transplantation. Eight weeks after transplantation, the motor function of PD rats was significantly improved as shown by water maze test (P < 0.0001) and apomorphine-induced rotation test (P < 0.0001) compared with rats receiving vehicle injection.

CONCLUSION

HiPSCs can be effectively induced to differentiate into DAPs capable of differentiating into functional neurons both in vivo and in vitro. In rat models of PD, the transplanted hiPSCs-DAPs can survive for more than 8 weeks in the MFB and differentiate into multiple functional neurocytes to ameliorate neurological deficits of the rats, suggesting the potential value of hiPSCs-DAPs transplantation for treatment of neurological diseases.

235 Assessing coding of diagnosis for atypical parkinsonian syndromes

Background

Atypical Parkinsonian syndromes, including Progressive Supranuclear Palsy (PSP), Multiple System Atrophy (MSA) and Corticobasal Syndrome (CBS), are rare neurodegenerative diseases. Reports showed that the use of the health services for patients with these diseases is underestimated. The NHS uses International Classification of Disease revision 10 (ICD-10) to code health use which has led to error in patient data for these diseases, as they are relatively new entries to this system and there were changes in coding practice in 2016.

Aims

To retrospectively investigate the scale of miscoding of PSP, MSA and CBS in England since the introduction of ICD-10.

Methods

Freedom of information requests were issued to 150 NHS trusts in England to investigate their method of coding and determine the coding error rate.

Results

The coding error rates prior to, and after 2016 respectively were: 29.5%, 0% (PSP); 3.8%, 2.3% (MSA); 24.2%, 24.2% (CBS). The indexing for CBS is difficult as no specific coding exists for CBS in ICD-10.

Conclusion

The high error rate for PSP is contributed by miscoding of PSP (G23.1) as MND (G12.2), due to the coding techniques employed. These errors have largely been rectified in later versions of ICD-10 with the exception of CBS.

ggz1g17@soton.ac.uk

Temporal association between antibiotic use and resistance in Gram-negative bacteria

The β-lactam/lactamase inhibitors (BLBLIs) combination drugs are considered an effective alternative to carbapenems. However, there is a growing concern that the increased use of BLBLIs may lead to increased resistance. This study determined the temporal association between the consumption of BLBLI and the antimicrobial resistance in Gram-negative bacteria. In this retrospective study, electronic data on the Gram-negative bacterial isolates, including A. baumannii, P. aeruginosa, E. coli, and K. pneumoniae from in-patients and susceptibility testing results were retrieved from the medical records of the clinical laboratory. A linear regression and cross-correlation analysis were performed on the acquired data. Increasing trends (p<0.05) in the consumption of BIBLI and carbapenem with a median use of 27.68 and 34.46 DDD/1000 PD per quarter were observed, respectively. A decreased trend (p=0.023) in the consumption of fluoroquinolones with a median use of 29.13 DDD/1000 PD per quarter was observed. The resistance rate of K. pneumoniae was synchronized with the BIBLI and carbapenem consumptions with a correlation coefficient of 0.893 (p=0.012) and 0.951 (p=0.016), respectively. The cross-correlation analysis against the consumption of BIBLI and meropenem resistant K. pneumoniae was peaked at 0-quarter lag (r=951, p=0.016). There was an increasing trend in the consumption of BLBLI and carbapenems. The increasing trend in the rates of resistance to piperacillin/tazobactam, in line with the increasing consumption of BLBLI, suggests that BLBLI has to be used with caution and cannot be directly considered as a long-term alternative to carbapenems.

[Targeted therapy of pyogenic sterile arthritis, pyoderma gangrenosum, and acne syndrome (PAPA): a case report and literature review]

Objective: To analyze the clinical course and targeted therapy of pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome. Methods: The clinical history of a 6-year-old boy with PAPA syndrome, who was admitted to Hong Kong University Shenzhen Hospital in September 2017, was reviewed. His genetic diagnosis was confirmed by whole exome sequencing. The response to targeted therapy was evaluated by comparing the inflammatory markers (erythrocyte sedimentation rate (ESR) and C reactive protein (CRP) and serum cytokines (interleukin (IL)-1, IL-6 and tumor necrosis factor-α (TNF-α)) before and after biological agents treatment. For literature review, "PAPA syndrome" and"PSTPIP1 gene"were used as keywords to retrieve papers published from January 1997 to December 2019 from Pubmed, Wanfang and CNKI database. Results: The patient was a 6-year-old boy, admitted to the hospital due to recurrent joint swelling and pain for more than 4 years. Before treatment, the CRP (256 mg/L), ESR (105 mm/1 h) and cytokines including serum TNF-α (7.43 ng/L), IL-1 (<5 ng/L), IL-6 (301 ng/L) were significantly elevated. Culture of the joint effusion was negative, but the IL-6 level was above 1 000 ng/L. MRI showed osteomyelitis at the lower end of the right femur. Gene detection found a heterozygous variation of PSTPIP1 gene (c.748G>A, p.E250K). Arthralgia once alleviated after the initiation of tocilizumab and infliximab, but recurred after 1 year of treatment. Thereafter, the anti-IL-1 receptor antagonist (Anakinra) was commenced, followed by a significant improvement of the arthralgia, and a complete remission during the follow-up. Besides, the level of CRP, ESR, serum TNF-α, IL-1 and IL-6 were all decreased to normal on the last followed up in December 2019. Literature review found 29 articles and 87 patients in total. The initial symptoms included those of arthritis (n=58), pyoderma gangrenosum (n=33), and acne (n=24). Among all the cases, 13 genotypes were confirmed, and 47 variations involved amino acid p.E250. Steroid and/or biological agents were used in most patients. Conclusions: PAPA syndrome should be suspected in children with recurrent pyogenic sterile arthritis, and an early diagnosis could be achieved by genetic test. Targeted treatment with biological agent may control the symptoms effectively. Biological agents can control symptoms of this disorder effectively.

Gastric cancer nodal tumour-stroma ratios influence prognosis

This study showed that nodal tumour-stroma ratio (NTSR) is an independent prognostic factor for overall and disease-free survival of patients with gastric cancer. Both relative stroma-rich primary tumour-stroma ratio (PTSR) and NTSR were independent negative prognostic factors for overall survival in gastric cancer. This study supports assessment of tumour-stroma ratio in the routine pathological diagnosis of gastric cancer. validated in node-positive disease.

Large debris dumps in the northern South China Sea

Knowledge of the abundance, source, and fate of marine debris in the deep sea is largely constrained thus far. Here, we report the existence of large deep-sea debris dumps that have not been reported before on the seafloor worldwide. Marine debris remarkably accumulated at ~1700-1800 m in the tributary submarine canyons of the Xisha Trough, northern South China Sea (SCS). Although marine debris in Xisha Trough is patchy, the debris abundance was as high as 36,818 and 51,929 items/km² at locations SY78 and SY82, respectively, which is one order of magnitude higher than that in other submarine canyons. We propose that most of the debris came from fishery and navigation activities, as indicated by the categories of debris collected from the seafloor dumps. Seasonal surface ocean currents of the SCS and geomorphology of submarine canyons possibly influence the movement of the debris from coasts to the deep seafloor.

The applied anatomy and clinical significance of the proximal, V1 segment of vertebral artery

BACKGROUND

The aim of the study was to probe the morphological features of the proximal segment (V1) of vertebral artery (VA) in a sample of Chinese cadavers.

MATERIALS AND METHODS

The origin, course and outer diameter at origin of the pre-vertebral part of the VAs were evaluated in 119 adult cadavers.

RESULTS

It was found that 94.12% of the VAs originated from the subclavian arteries, bilaterally. The variant origins were present in 5.88% of the cadavers and all originated directly from the arch of the aorta. All the variations were observed on the left side of male cadavers. The average outer diameters at origin of the normal and variation groups were 4.35 ± 1.00 mm and 4.82 ± ± 1.42 mm, respectively, p = 0.035. In the normal group, but not in the variation group, the average diameter in the males was significantly larger than that in the females (4.50 ± 0.99 mm, 3.92 ± 0.92 mm, respectively, p = 0.000). In addition, only 5 cadavers in the normal group had hypoplastic VAs (4.20%, 4 males, 3 right-sided). Vertebral artery dominance (VAD) was present in 91 (69 males) out of 112 cadavers and more common on the left (n = 48). In addition, 3 cadavers satisfied conditions for coexistence of VAD and vertebral artery hypoplasia. All 7 cadavers in the variation group exhibited VAD, which was more common on the right side (n = 5).

CONCLUSIONS

The morphologic variations and frequencies described above have implications for the early prevention, abnormal anatomy detection, accurate diagnosis, safe surgery and endovascular treatment of cardiovascular and neurological disease.

A long-acting pegylated recombinant human growth hormone (Jintrolong® ) in healthy adult subjects: Two single-dose trials evaluating safety, tolerability and pharmacokinetics

WHAT IS KNOWN AND OBJECTIVE

Jintrolong^® is a pegylated recombinant human growth hormone (rhGH) (PEG-rhGH) developed for weekly subcutaneous (sc) injection. The current human tolerability trial and pharmacokinetics (PK) trial evaluated the safety, tolerability and PK of single-dose Jintrolong^® injection in healthy adult subjects.

METHODS

Both trials were single-centre, randomized, open-label and single-dose studies. In the human tolerability trial, 34 healthy subjects were randomized to receive single-dose Jintrolong^® sc injection (0.01, 0.06, 0.2, 0.5 or 0.8 mg/kg) or placebo. In the PK study, 30 healthy male subjects were evenly randomized into 3 groups to receive single-dose Jintrolong^® sc injection (0.1, 0.2 or 0.4 mg/kg), and the subjects receiving 0.4 mg/kg Jintrolong^® were given a single sc injection of conventional rhGH (0.067 mg/kg) after a 14-day washout period. Safety and PK profiles of Jintrolong^® were evaluated.

RESULTS AND DISCUSSION

Jintrolong^® was well tolerated with no serious adverse events or local injection responses. The PK trial showed that the plasma growth hormone concentration elevated quickly and stayed at peak level between 12 and 48 hours post-Jintrolong^® injection, then decreased gradually back to baseline within 168 hours. Compared to single-dose conventional rhGH, Jintrolong^® at all doses demonstrated significantly longer half time and time to maximum plasma concentration, lower clearance and higher systemic drug exposure, indicating prolonged presence of GH in the subjects' circulation. Additionally, systemic exposure to Jintrolong^® increased in a dose-dependent manner.

WHAT IS NEW AND CONCLUSION

Single-dose Jintrolong^® injection was well tolerated in healthy adult subjects, and the maximum tolerable dose was no lower than 0.8 mg/kg. Jintrolong^® was long-acting with the potential for weekly administration.

Enzymatic [4+2] Cycloadditions in the Biosynthesis of Spirotetramates and Spirotetronates

The Diels-Alder reaction is a quintessential type of [4+2] cycloaddition that remains one of the most intriguing transformations in synthetic chemistry. This reaction has long been envisaged to participate in the biosynthesis of a number of cyclohexene-containing natural products, although the question of whether a bona fide Diels-Alderase exists remains unsolved. In nature, there are remarkably few enzymes known to have the activity of [4+2] cycloaddition. These enzymes are phylogenetically distinct and are often classified according to the specific chemical structures. The variation of protein ancestors and in many cases the instability/complexity of the substrates and products pose a significant challenge in identification of the [4+2] cycloaddition catalysts using general homology-based mining approaches. We here provide the detailed description of the multiple comparison-based strategy and methods for the characterization of two distinct types of dedicated [4+2] cyclases (eg, PyrE3 and PyrI4) in the biosynthesis of spirotetramates and spirotetronates, where they act in tandem for coordinated cross-bridging of a linear polyene intermediate into a enantiomerically pure pentacyclic core. The search of new protein scaffolds with the [4+2] cycloaddition activity could enrich the pool of the candidates for mechanistic examination of a true enzymatic Diels-Alder reaction. The protocols presented in this study would also be applicable to the study of other functionally similar but phylogenetically different proteins, eg, the spiroketal cyclases.

Single- and Multiple-dose Pharmacokinetic, Safety and Tolerability Study of Mildronate Injection in Healthy Chinese Subjects Pharmacokinetic of Mildronate Injection

Mildronate is an agent for cardioprotection and neuroprotection. This study aimed to evaluate the pharmacokinetic (PK) profiles, safety and tolerability of mildronate injection after single escalating doses and multiple doses in healthy Chinese subjects. We performed a randomized, open-label, single- and multiple-dose phase I trial including 3 doses of mildronate: 250, 500 and 750 mg. Plasma and urine samples were collected and concentrations of mildronate were analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). PK parameters were calculated using noncompartmental analysis. Safety and tolerability was assessed throughout noting subjects' vital signs and monitoring adverse events (AEs) and conduct a comprehensive physical examination and laboratory analyses before and after the study. There was no significant difference in C 0, AUC0-t, AUC0-∞ among 3 single-dose groups, whereas T 1/2 had significant statistical difference which may be caused by the inhibition of metabolic enzymes. Single- and multiple-dose intravenous injection of mildronate exhibited linear PK profiles in the range of 250-750 mg. An unconspicuous accumulation phenomenon was found after multiple-dose mildronate administration. No significant gender difference was found and mildronate is primarily excreted by the kidney. No serious AEs were observed. The formulation was safe and well tolerated from 250 to 750 mg.

Methylation of RASSF10 promotes cell proliferation and serves as a docetaxel resistant marker in human breast cancer

Breast cancer is a leading cause of death among females worldwide. However, the mechanisms of breast cancer remain largely unclear. RASSF10 is frequently methylated in certain types of human cancers. To understand the mechanism of RASSF10 in breast cancer, samples of breast cancer cell lines, primary cancer, breast tissue adjacent to cancer, and normal breast tissue were investigated in this study. Methylation specific PCR (MSP), flow cytometry, western blot, and siRNA knockdown assay were used. Complete methylation was found in MCF7, MDA-MB-435, and MDA-MB-468 cells, partial methylation was found in ZR75-1 cells, and unmethylation was revealed in SKBR3 cells. Loss of RASSF10 expression was found in MCF7, MDA-MB-435, and MDA-MB-468 cells, and high expression of RASSF10 was found in ZR75-1 and SKBR3 cells. The expression of RASSF10 was induced by 5-aza-2'-deoxycytidine (5-Aza) in MCF7, MDA-MB-435, and MDA-MB-468 cells. RASSF10 methylation was found in 77.8% (49/63) of primary breast cancer and 17.8% (8/45) of adjacent tissue samples. No methylation was found in normal breast tissue samples. Restoration of RASSF10 expression inhibited cell proliferation and induced G2/M phase arrest in MCF7 and MDA-MB-468 cells. RASSF10 sensitized these cells to docetaxel. RASSF10 induced apoptosis and activated P53 signaling in breast cancer cells. In conclusion, RASSF10 is frequently methylated in human breast cancer and infrequently in adjacent tissue samples. RASSF10 methylation may serve as an early detective marker. The expression of RASSF10 is regulated by promoter region methylation. Since restoration of RASSF10 expression sensitized breast cancer cells to docetaxel, RASSF10 methylation is a potential docetaxel resistant marker. RASSF10 suppresses breast cancer growth by activating P53 signaling.

Carbon nanotube growth for through silicon via application

Through silicon via (TSV) technology is key for next generation three-dimensional integrated circuits, and carbon nanotubes (CNT) provide a promising alternative to metal for filling the TSV. Three catalyst preparation methods for achieving CNT growth from the bottom of the TSV are investigated. Compared with sputtering and evaporation, catalyst deposition using dip-coating in a FeCl2 solution is found to be a more efficient method for realizing a bottom-up filling of the TSV (aspect ratio 5 or 10) with CNT. The CNT bundles grown in 5 min exceed the 50 μm length of the TSV and are multi-wall CNT with three to eight walls. The CNT bundles inside the TSV were electrically characterized by creating a direct contact using a four-point nanoprober setup. A low resistance of the CNT bundle of 69.7 Ω (297 Ω) was measured when the CNT bundle was contacted midway along (over the full length of) the 25 μm deep TSV. The electrical characterization in combination with the good filling of the TSV demonstrates the potential use of CNT in fully integrated TSV applications.

Bioequivalence evaluation of 2 tablet formulations of entecavir in healthy chinese volunteers: a single-dose, randomized-sequence, open-label crossover study

A randomized, 2-way crossover study was conducted in healthy Chinese male volunteers to evaluate the bioequivalence of a new generic formulation of entecavir (CAS 142217-69-4) tablets (test) and the available branded formulation (reference) to meet the requirements for marketing the test product in China. Test and reference tablets were administered as a single dose on 2 treatment days separated by a 2-week washout period. Blood samples were collected for a period of 24 h following drug administration. Plasma concentration of entecavir was determined by a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method. Pharmacokinetic parameters were calculated using a noncompartmental model. Bioequivalence was determined by calculating 90% CIs for the ratios of Cmax, AUC0-t and AUC0-∞ values for the test and reference products. Tolerability was assessed by monitoring vital signs, laboratory tests and interviews with the volunteers before administration and every 2 h during the study. The 90% CIs of entecavir for Cmax, AUC0-t and AUC0-∞ were 95.2-106.9%, 98.4-104.6% and 97.3-104.4%, respectively, which fell within the interval of 80-125%. No clinically important adverse effects were reported. These results suggested that the test formulation of entecavir tablets met the regulatory criterion for bioequivalence to the reference formulation.

Abnormal motor reflexes and dormant facial motor neurons in rats with facial-facial anastomosis

After facial nerve injury, some post-paralysis sequelae, such as synkinesis, hemispasm and 'crocodile tears' syndrome appear. The psychosocial impact of these sequelae is unavoidable. Despite recent advances and the growing popularity of this field, the pathophysiological mechanisms of facial nerve injury and regeneration are still not well understood. In this report, an abnormal motor reflex coincident with synkinetic facial movement was examined in a rat model using the blink reflex technique. Some dormant facial motor neurons were found which could not innervate through the suture site but remained alive. These results suggest that such dormant neurons might exert roles distinct from those of re-innervated neurons during facial nerve injury and regeneration. Further study is required to elucidate the biomolecular structure and electrophysiological features of such neurons.

Controlling the catalyst during carbon nanotube growth

We have recently been able to grow single-walled carbon nanotubes by purely thermal chemical vapour deposition (CVD) at temperatures as low as 400 degrees C. This has been achieved by separating the catalyst pre-treatment step from the growth step. In the pre-treatment step, a thin film catalyst is re-arranged into a series of nano-droplets, which are then the active catalysts. Both steps have been studied by in-situ environmental transmission electron microscopy and X-ray photoemission spectroscopy. We have also studied the catalyst yield, the weight of nanotubes grown per weight of transition metal catalyst. Using very thin layers of Fe on Al2O3 support in a remote plasma-assisted CVD, we have achieved yields of order 100,000. This may be due to control of catalyst poisoning by ensuring an etching path.

Enhanced Maturation and Functional Capacity of Dendritic Cells Induced by Mannosylated L2 Domain of ErbB2 Receptor

The nature of antigens and functional state of dendritic cells (DC) are important in antigen presentation. The ability of DC for the induction of T-cell responses is promoted by maturation. It has been confirmed that mannose receptors mediate highly efficient endocytosis and presentation of mannosylated proteins. In the present study, L2 domain of ErbB2 ectodomain was expressed in Escherichia coli, purified and mannosylated. The maturation and functional capacity of DC induced by mannosylated L2 (mL2) protein were investigated. The results showed that L2 protein could induce DC maturation, which was accompanied by elevated expression of MHC and co-stimulatory molecules. The effect of mL2 protein on DC maturation was more remarkable than that of non-mL2 proteins. Uptake of mL2 antigens by DC was more efficient. Furthermore, the T cells can be stimulated to proliferate in vitro and secrete Th1 and Th2 cytokines. Higher levels of both IFN-gamma and IL-10 were detected from the T cells stimulated by mL2-pulsed DC, suggesting a concurrent activation of CD4+ and CD8+ T cells. The results demonstrated that L2 domain of ErbB2 receptor is an immunodominant molecule. The mL2 domain of ErbB2 can induce an enhanced maturation and functional capacity of DC. It may become an effective strategy to induce anti-ErbB2 response.

Expression of estrogen receptors ERalpha and ERbeta in endometrial hyperplasia and adenocarcinoma

We assessed the expression of estrogen receptors (ER)alpha and ERbeta in 114 human endometrial hyperplasia and adenocarcinomas. The aim of this study was to determine the expression of both ER isoforms in human endometrial tissue by immunohistochemistry. From normal proliferation to simple and complex hyperplasia, the expression of ERalpha was increased (P < 0.05), while ERbeta did not change much (P > 0.05). In atypia hyperplasia and adenocarcinoma, both ERalpha and ERbeta were decreased significantly (P < 0.05). Most endometrial adenocarcinomas expressed ERalpha, either alone or in combination with ERbeta, and the ERbeta/ERalpha ratio was decreased when compared to normal proliferation (P < 0.05). Also, we found that the expression of ERalpha and ERbeta has no relationship with the status of lymph node of adenocarcinoma (P > 0.05). Both ERalpha and ERbeta play an important role in endometrial hyperplasia and carcinomas, the levels of ERalpha and ERbeta appear be used as prognostic indicators.

Expression of estrogen receptors ERα and ERβ in endometrial hyperplasia and adenocarcinoma

We assessed the expression of estrogen receptors (ER)α and ERβ in 114 human endometrial hyperplasia and adenocarcinomas. The aim of this study was to determine the expression of both ER isoforms in human endometrial tissue by immunohistochemistry. From normal proliferation to simple and complex hyperplasia, the expression of ERα was increased (P < 0.05), while ERβ did not change much (P > 0.05). In atypia hyperplasia and adenocarcinoma, both ERα and ERβ were decreased significantly (P < 0.05). Most endometrial adenocarcinomas expressed ERα, either alone or in combination with ERβ, and the ERβ/ERα ratio was decreased when compared to normal proliferation (P < 0.05). Also, we found that the expression of ERα and ERβ has no relationship with the status of lymph node of adenocarcinoma (P > 0.05). Both ERα and ERβ play an important role in endometrial hyperplasia and carcinomas, the levels of ERα and ERβ appear be used as prognostic indicators.

Matrix metalloproteinase 2 and tissue inhibitor of metalloproteinase 2 expression is not regulated by norgestimate or norelgestromin

Steroid hormones regulate endometrial expression of matrix metalloproteinases (MMPs) and their inhibitors. Synthetic progestins are widely used in oral contraceptives and for hormone replacement therapy. To assess whether the synthetic progestins norgestimate and its derivative norelgestromin (17-deacetylnorgestimate) modulate the expression of MMPs, Ishikawa endometrial cancer cells were separately treated with 17 beta-estradiol, 17 alpha-hydroxyprogesterone, norgestimate and norelgestromin. Culture supernatants were assayed for MMPs 2, 3 and 9, and for tissue inhibitors of MMPs (TIMP-1 and TIMP-2) by enzyme-linked immunosorbent assays (ELISAs). No marked modulation of MMP-2 and TIMP-2 expression was observed upon incubation of the cells with the synthetic progestins. By ELISA, neither MMP-3 or MMP-9 nor TIMP-1 immunoreactivity was detected. Interestingly, TIMP-2 expression was down-regulated by 17 beta-estradiol and 17 alpha-hydroxyprogesterone.

LacSwitch II regulation of connexin43 cDNA expression enables gap-junction single-channel analysis

Metabolic and electrical coupling through gap junction channels is implicated in cell differentiation, tissue homeostasis, and electrotonic propagation of signals in excitable tissues. The characterization of gating properties of these channels requires electrophysiological recordings at both single- and multiple-channel levels. Hence, a system that is able to control connexin expression by external means would provide a useful tool. To regulate the expression of connexins in cells, plasmids encoding a transactivator and/or a lac-operon IPTG response-dependent Cx43 target gene were transfected into communication-deficient N2a neuroblastoma cells. Immunoblotting, dye coupling, and electrophysiological methods revealed that expression of Cx43 in selected clones could be tightly regulated. After 15-20 h of acute induction with IPTG, cell-to-cell communication reached its peak with junctional conductances of 15-30 nS. Chronic induction at specific doses of IPTG produced constant, controlled levels of Cx43 expression, which were reflected by predictable junctional coupling levels. These conditions allowed prolonged recordings from either lowly or highly coupled cells, making lac operon an ideal regulatory system for channel gating studies at a single-channel level.

[A textual research on drinking disease and antidrinking remedies]

This subject is investigated through three aspects, viz., definition of drinking disease, its manifestations and treatment, and recipes and drug for antidrinking. The term "drinking disease" (Jiu Bing) was first recorded in Wang Shuhe's Canon of Pulsology, while abnormal drinking (Jiu Bo) was mentioned in Miraculous Pivot (Ling Shu). On Pathogenesis Manifestation of all diseases (Zhu Bing Yuan Hou Lun) gives the pathology and etiology. Great influence was exerted from Jin-yuan dynasties concerning its treatment. Zhang Jiebin expounded the comatous syndrome due to drinking (Jiu Jue). The earliest antidrinking drug was recorded in Shen Nong's Classic of Herbology. Through investigation, the commonly applied drug for relieving drunk include Flos Puerariae, Fructus Hovenariae, while the famous recipe for relieving drunk is Anti-tipsy Decoction of Flos Puerariae.

Chlamydia pneumoniae major outer membrane protein is a surface-exposed antigen that elicits antibodies primarily directed against conformation-dependent determinants

The major outer membrane protein (MOMP) of Chlamydia trachomatis serovariants is known to be an immunodominant surface antigen. Moreover, it is known that the C. trachomatis MOMP elicits antibodies that recognize both linear and conformational antigenic determinants. In contrast, it has been reported that the MOMP of Chlamydia pneumoniae is not surface exposed and is immunorecessive. We hypothesized that the discrepancies between C. trachomatis and C. pneumoniae MOMP exposure on intact chlamydiae and immunogenic properties might be because the focus of the host's immune response is directed to conformational epitopes of the C. pneumoniae MOMP. We therefore conducted studies aimed at defining the surface exposure of MOMP and the conformational dominance of MOMP antibodies. We present here a description of C. pneumoniae species-specific monoclonal antibody (MAb), GZD1E8, which recognizes a conformational epitope on the surface of C. pneumoniae. This MAb is potent in the neutralization of C. pneumoniae infectivity in vitro. Another previously described C. pneumoniae species-specific monoclonal antibody, RR-402, displayed very similar characteristics. However, the antigenic determinant recognized by RR-402 has yet to be identified. We show by immunoprecipitation of C. pneumoniae with GZD1E8 and RR-402 MAbs and by mass spectrometry analysis of immunoprecipitated proteins that both antibodies GZD1E8 and RR-402 recognize the MOMP of C. pneumoniae and that this protein is localized on the surface of the organism. We also show that human sera from C. pneumoniae-positive donors consistently recognize the MOMP by immunoprecipitation, indicating that the MOMP of C. pneumoniae is an immunogenic protein. These findings have potential implications for both C. pneumoniae vaccine and diagnostic assay development.

Identification of a chlamydial protease-like activity factor responsible for the degradation of host transcription factors

Microbial pathogens have been selected for the capacity to evade or manipulate host responses in order to survive after infection. Chlamydia, an obligate intracellular pathogen and the causative agent for many human diseases, can escape T lymphocyte immune recognition by degrading host transcription factors required for major histocompatibility complex (MHC) antigen expression. We have now identified a chlamydial protease- or proteasome-like activity factor (CPAF) that is secreted into the host cell cytosol and that is both necessary and sufficient for the degradation of host transcription factors RFX5 and upstream stimulation factor 1 (USF-1). The CPAF gene is highly conserved among chlamydial strains, but has no significant overall homology with other known genes. Thus, CPAF represents a unique secreted protein produced by an obligate intracellular bacterial pathogen to interfere with effective host adaptive immunity.

Chlamydia pneumoniae infection significantly exacerbates aortic atherosclerosis in an LDLR-/- mouse model within six months

We have previously shown that infection with the C. pneumoniae AR39 strain once monthly for 9 consecutive months significantly exacerbated atherosclerosis in mice with LDL receptor deficiency (LDLR-/-) in the presence of a high cholesterol diet. To further optimize the LDLR-/- mouse model for studying the mechanisms of C. pneumoniae atherogenesis, we have tested a different infection protocol with intranasal inoculation twice monthly for 6 consecutive months in the present study. We found that C. pneumoniae infection for 6 months was sufficient to produce a 130%, significantly greater exacerbation of aortic atherosclerosis in LDLR-/- mice in the presence of a high cholesterol diet. Mice receiving a high cholesterol diet alone displayed a lesion area index of 18.2 +/- 6.1 (S.D.) while mice treated with both the high cholesterol diet and C. pneumoniae infection had a lesion area index of 41.8 +/- 15.2 (S.D.). However, the chlamydial infection did not significantly alter the mouse serum total cholesterol or the LDL levels induced by the high cholesterol diet. This study not only confirms our previous findings that C. pneumoniae infection can exacerbate aortic atherosclerosis lesion in the LDLR-/- mice, but also further optimizes the LDLR-/- mouse model for future mechanism studies.

A motif shared by TFIIF and TFIIB mediates their interaction with the RNA polymerase II carboxy-terminal domain phosphatase Fcp1p in Saccharomyces cerevisiae

Transcription by RNA polymerase II is accompanied by cyclic phosphorylation and dephosphorylation of the carboxy-terminal heptapeptide repeat domain (CTD) of its largest subunit. We have used deletion and point mutations in Fcp1p, a TFIIF-interacting CTD phosphatase, to show that the integrity of its BRCT domain, like that of its catalytic domain, is important for cell viability, mRNA synthesis, and CTD dephosphorylation in vivo. Although regions of Fcp1p carboxy terminal to its BRCT domain and at its amino terminus were not essential for viability, deletion of either of these regions affected the phosphorylation state of the CTD. Two portions of this carboxy-terminal region of Fcp1p bound directly to the first cyclin-like repeat in the core domain of the general transcription factor TFIIB, as well as to the RAP74 subunit of TFIIF. These regulatory interactions with Fcp1p involved closely related amino acid sequence motifs in TFIIB and RAP74. Mutating the Fcp1p-binding motif KEFGK in the RAP74 (Tfg1p) subunit of TFIIF to EEFGE led to both synthetic phenotypes in certain fcp1 tfg1 double mutants and a reduced ability of Fcp1p to activate transcription when it is artificially tethered to a promoter. These results suggest strongly that this KEFGK motif in RAP74 mediates its interaction with Fcp1p in vivo.

[Inner-hemangioma ligation and pingyangmycin injection in hemangioma (with 30 cases report)]

OBJECTIVE

To provide a simple and safe surgical approach in treating cavernous and racemose hemangioma.

METHODS

First cross-ligate the hemangioma, as to divide the tumor into independent compartments, them inject pingyangmycin into the compartments respectively.

RESULTS

There are 30 cases in this group (35 hemangiomas). Twenty-four cases (28 hemangiomas) were totally cured, accounting for 80%; Six cases were improved (7 hemangiomas) for 20%; There was no ineffective case.

CONCLUSION

"Inner-hemangioma ligation and injection of pingyangmycin" has broad surgical indications, with desirable outcome in treating cavernous and racemose hemangioma, especially those unsuitable for surgery, or ineffective simply by inner-hemangioma injection.

Degradation of transcription factor RFX5 during the inhibition of both constitutive and interferon gamma-inducible major histocompatibility complex class I expression in chlamydia-infected cells

We have previously shown that the obligate intracellular pathogen chlamydia can suppress interferon (IFN)-gamma-inducible major histocompatibility complex (MHC) class II expression in infected cells by degrading upstream stimulation factor (USF)-1. We now report that chlamydia can also inhibit both constitutive and IFN-gamma-inducible MHC class I expression in the infected cells. The inhibition of MHC class I molecule expression correlates well with degradation of RFX5, an essential downstream transcription factor required for both the constitutive and IFN-gamma-inducible MHC class I expression. We further demonstrate that a lactacystin-sensitive proteasome-like activity identified in chlamydia-infected cell cytosolic fraction can degrade both USF-1 and RFX5. This proteasome-like activity is dependent on chlamydial but not host protein synthesis. Host preexisting proteasomes may not be required for the unique proteasome-like activity. These observations suggest that chlamydia-secreted factors may directly participate in the proteasome-like activity. Efforts to identify the chlamydial factors are underway. These findings provide novel information on the molecular mechanisms of chlamydial evasion of host immune recognition.

Using antibody catalysis to study the outcome of multiple evolutionary trials of a chemical task

Catalytic aldolase antibodies generated by immunization with two different, but structurally related, beta-diketone haptens were cloned and sequenced to study similarities and differences between independently evolved catalysts. Kinetic and sequence analysis coupled with mutagenesis, structural, and modeling studies reveal that the defining event in the evolution of these catalysts was a somatic mutation that placed a lysine residue in a deep, yet otherwise unrefined, hydrophobic pocket. We suggest that covalent chemistries may be as readily selected from the immune repertoire as the traditional noncovalent interactions that have formed the basis of immunochemistry until this time. Further, we believe that these experiments recapitulate the defining events in the evolution of nature's enzymes, particularly as they relate to chemical mechanism, catalytic promiscuity, and gene duplication.

Molecular cloning, sequencing and expression of obese gene in the Chinese

OBJECTIVE

To construct the human obese (ob) cDNA clone in the Chinese, and analyze the expression of the ob gene in adipose tissue of obese, non-obese subjects and nooinsulin-dependent diabetes mellitus (NIDDM) Chinese patients.

METHODS

A ob cDNA clone was isolated by reverse transcription polymerase chain reaction (RT-PCR). Four groups of Chinese subjects participated in the study: 1) 12 obese subjects [body mass index (BMI): 28.5 +/- 2.3 kg/m2]; 2) 11 non-obese subjects (BMI: 21.0 +/- 1.5 kg/m2); 3) 8 obese NIDDM patients (BMI: 27.0 +/- 1.4 kg/m2); 4) 11 non-obese NIDDM patients (BMI: 21.2 +/- 1.4 kg/m2). The expression of ob gene mRNA in abdominal subcutaneous adipose tissue was examined using RNA dot blot hybridization with a digoxigenin-labeled human ob cDNA probe. The hybridized signals were quantitated by densitometry.

RESULTS

A full human ob cDNA fragment which included a glutamine codon at +49 was obtained. A base substitution (A to G) in the coding region at position 287 was found, resulting in a glutamine being replaced by an arginine. Expression of the ob gene was significantly higher in Chinese obese subjects compared to non-obese ones (P < 0.05), and positively correlated with the BMI. No significant difference in the amount of ob mRNA was detected between non-diabetic and diabetic groups at the same BMI level.

CONCLUSIONS

We constructed a full length human ob cDNA clone. The expression of the ob gene was significantly higher in Chinese obese subjects than in non-obese ones. The metabolic and hormonal changes associated with NIDDM are not the main factors regulating the expression of the ob gene.

Broadening the Aldolase Catalytic Antibody Repertoire by Combining Reactive Immunization and Transition State Theory: New Enantio- and Diastereoselectivities

Nine efficient aldolase antibodies were generated by using hapten 1. This hapten unites reactive immunization and the transition state analogue approach in a single molecule. Characterization of two of these antibodies reveals that they are highly proficient (up to 1000-fold better than any other antibody catalyst) and enantioselective catalysts for aldol and retro-aldol reactions and exhibit enantio- and diastereoselectivities opposite to that of antibody 38C2.

[An outline on the early pharmacetical development before Galen]

The period before Galen (including his time) is known as ancient herbal period of pharmacy, which is an important component in the developing history of pharmacy. Some characteristics and rules about early pharmacy development are reflectd from the origin of pharmacy, Babylonian - Assyrian pharmacy, ancient Egyptian pharmacy, ancient Greek pharmacy and Rome pharmacy in different periods and areas.

Chlamydia inhibits interferon gamma-inducible major histocompatibility complex class II expression by degradation of upstream stimulatory factor 1

We report that chlamydiae, which are obligate intracellular bacterial pathogens, can inhibit interferon (IFN)-gamma-inducible major histocompatibility complex (MHC) class II expression. However, the IFN-gamma-induced IFN regulatory factor-1 (IRF-1) and intercellular adhesion molecule 1 (ICAM-1) expression is not affected, suggesting that chlamydia may selectively target the IFN-gamma signaling pathways required for MHC class II expression. Chlamydial inhibition of MHC class II expression is correlated with degradation of upstream stimulatory factor (USF)-1, a constitutively and ubiquitously expressed transcription factor required for IFN-gamma induction of class II transactivator (CIITA) but not of IRF-1 and ICAM-1. CIITA is an obligate mediator of IFN-gamma-inducible MHC class II expression. Thus, diminished CIITA expression as a result of USF-1 degradation may account for the suppression of the IFN-gamma-inducible MHC class II in chlamydia-infected cells. These results reveal a novel immune evasion strategy used by the intracellular bacterial pathogen chlamydia that improves our understanding of the molecular basis of pathogenesis.

Immunity to Chlamydia trachomatis mouse pneumonitis induced by vaccination with live organisms correlates with early granulocyte-macrophage colony-stimulating factor and interleukin-12 production and with dendritic cell-like maturation

As is true for other intracellular pathogens, immunization with live Chlamydia trachomatis generally induces stronger protective immunity than does immunization with inactivated organism. To investigate the basis for such a difference, we studied immune responses in BALB/c mice immunized with viable or UV-killed C. trachomatis mouse pneumonitis (MoPn). Strong, acquired resistance to C. trachomatis infection was elicited by immunization with viable but not dead organisms. Immunization with viable organisms induced high levels of antigen-specific delayed-type hypersensitivity (DTH), gamma interferon production, and immunoglobulin A (IgA) responses. Immunization with inactivated MoPn mainly induced interleukin-10 (IL-10) production and IgG1 antibody without IgA or DTH responses. Analysis of local early cytokine and cellular events at days 3, 5, and 7 after peritoneal cavity immunization showed that high levels of granulocyte-macrophage colony-stimulating factor and IL-12 were detected with viable but not inactivated organisms. Furthermore, enrichment of a dendritic cell (DC)-like population was detected in the peritoneal cavity only among mice immunized with viable organisms. The results suggest that early differences in inducing proinflammatory cytokines and activation and differentiation of DCs may be the key mechanism underlying the difference between viable and inactivated organisms in inducing active immunity to C. trachomatis infection.

Interleukin-12 production is required for chlamydial antigen-pulsed dendritic cells to induce protection against live Chlamydia trachomatis infection

Immunization with dendritic cells pulsed ex vivo with antigens has been successfully used to elicit primary antigen-specific immune responses. We report that mouse bone marrow-derived dendritic cells pulsed with inactivated chlamydial organisms induced strong protection against live chlamydial infection in a mouse lung infection model. Either the dendritic cells or chlamydial organisms alone or macrophages similarly pulsed with chlamydial organisms failed to induce any significant protection. These observations suggest that dendritic cells can efficiently process and present chlamydial antigens to naive T cells in vivo. Mice immunized with the chlamydia-pulsed dendritic cells preferentially developed a Th1 cell-dominant response while mice immunized with the other immunogens did not, suggesting a correlation between a Th1 cell-dominant response and protection against chlamydial infection. We further found that dendritic cells produced a large amount of interleukin 12 (IL-12) upon ex vivo pulsing with inactivated chlamydial organisms, which may allow the dendritic cells to direct a Th1 cell-dominant response. Dendritic cells from mice deficient in the IL-12 p40 gene failed to produce IL-12 after a similar ex vivo pulse with chlamydial organisms, and more importantly, immunization with these dendritic cells failed to induce a Th1 cell-dominant response and did not induce strong protection against chlamydial infection. Thus, the ability of dendritic cells to efficiently process and present chlamydial antigens and to produce IL-12 upon chlamydial-organism stimulation are both required for the induction of protection against chlamydial infection. This information may be useful for the further design of effective chlamydial vaccines.

Calcineurin B- and calmodulin-binding preferences identified with phage-displayed peptide libraries

Calcineurin B (CnB) and calmodulin (CaM) are two structurally similar but functionally distinct 'EF-hand' Ca2+-binding proteins. CnB is the regulatory subunit of the CaM-stimulated protein phosphatase, calcineurin. CaM is a unique multifunctional protein that interacts with and modulates the activity of many target proteins. CnB and CaM are both required for the full activation of the phosphatase activity of calcineurin and are not interchangeable. The two proteins recognize distinct binding sites on calcineurin A subunit (CnA) and perform different functions. Phage-displayed peptide libraries (pIII and pVIII libraries) were screened with CnB and CaM to isolate peptides that could then be compared to determine if there were binding preferences of the two proteins. The Ca2+-dependent binding of phage-displayed peptides to CnB and CaM is specifically blocked by synthetic peptides derived from the CnB-binding domain of CnA and the CaM-binding domain of myosin light chain kinase respectively. Both CnB- and CaM-binding peptides have a high content of tryptophan and leucine, but CnB-binding peptides are more hydrophobic than CaM-binding peptides. CnB-binding peptides are negatively charged with clusters of hydrophobic residues rich in phenylalanine, whereas the CaM-binding peptides are positively charged and often contain an Arg/Lys-Trp motif. The binding preferences identified with peptide libraries are consistent with the features of the CnB-binding domains of all CnA isoforms and the CaM-binding domains of CaM targets.

The atherogenic effects of chlamydia are dependent on serum cholesterol and specific to Chlamydia pneumoniae

Epidemiological investigations have linked Chlamydia pneumoniae infection to atherosclerosis. It is not clear, however, whether C. pneumoniae infection plays a causal role in the development of atherosclerosis. Mice with low-density lipoprotein receptor deficiency were induced to develop atherosclerotic lesions in aorta with a cholesterol-enriched diet that increased serum cholesterol by two- to threefold. Using this mouse model, we found that the chlamydial infection alone with either the C. pneumoniae AR39 or the C. trachomatis MoPn strain failed to induce any significant atherosclerotic lesions in aorta over a period of nine months. However, in the presence of a high-cholesterol diet, infection with the C. pneumoniae AR39 strain significantly exacerbated the hypercholesterolemia-induced atherosclerosis, demonstrating that a hypercholesterolemic condition is required for the C. pneumoniae to aggravate the development of atherosclerosis. Although both AR39 and MoPn antigens were detected in aorta of mice infected with the corresponding strains, only mice infected with the C. pneumoniae strain AR39 displayed enhanced atherosclerotic lesions, suggesting that the C. pneumoniae species may possess a unique atherogenic property. This study may provide a model for further understanding the mechanisms of C. pneumoniae atherogenesis and evaluating chlamydial intervention strategies for preventing the advancement of atherosclerotic lesions enhanced by C. pneumoniae infection.

[An experimental study on bone potentials at fracture site with axial interfragmental gradient compression]

OBJECTIVE

To evaluate the mechanism of stress generated potentials in compressive fixation leading to the primary healing.

METHODS

Eighteen fresh sheep tibiae were divided equally into three groups, and all specimen were fractured artificially and imposed "prestressing" at fracture sites with tension device and plate, meanwhile stainless wire tension band was used in the place opposite to plate. The interfragmental pressure was exerted when applied plates, which were 98.62 +/- 19.74 N, 137.93 +/- 8.13 N and 169.20 +/- 11.33 N. Bone potentials at fracture sites were recorded with reference to the potential measurement system by Friedenberg and Brighton (1966).

RESULTS

There was no significant statistical difference in bone potentials when made comparison between before and after compression fixation in each group and among groups of different axial interfragmental gradient compressions.

CONCLUSION

The mechanism of stress generated potentials may not exist in primary healing with compressive fixation.

Contribution of the absence of aspartic acid at position 57 of the HLA-DQ beta chain to predisposition to insulin-dependent diabetes mellitus in a southern Chinese population

OBJECTIVE

To investigate the association of the absence or presence of aspartic acid at position 57 of the HLA-DQ beta chain (NA or A) with susceptibility or resistance to insulin-dependent diabetes mellitus (IDDM) in a Southern Chinese population.

METHODS

Sixty-nine IDDM patients and 47 healthy controls in a Southern Chinese population were HLA-DQB1 genotyped by one-step sequence specific polymerase chain reaction (ssPCR).

RESULTS

The frequencies of NA and A were 64.5% and 35.5% in the IDDM patients, and 40.4% and 59.6% in the control subjects respectively (RR for NA was 2.68, P < 0.01). The frequencies of NA/NA, NA/A and A/A phenotypes were 47.8%, 33.3% and 18.8% in the IDDM patients, and 31.9%, 17.0% and 51.1% in the controls respectively (P < 0.01). The frequency of A/A phenotype was significantly lower in the IDDM patients than in the control subjects (RR = 0.22, P < 0.01). DQB1* 0302 and DQB1* 0201 were more frequent in IDDM patients than in control subjects. The younger the age of IDDM onset, the higher the allele frequencies of DQB1* 0201 and DQB1* 0302.

CONCLUSION

The present study suggests that the NA confers the susceptibility to IDDM, while the A confers the protection against IDDM in patients of Southern Chinese origin. These associations are more clearcut in childhood-onset IDDM patients.