Pleomorphic rhabdomyosarcoma of the vagina: A case report

BACKGROUND

Rhabdomyosarcoma (RMS) of the vagina in postmenopausal women is an extremely rare malignant tumor that was originally described as a unique group of soft tissue sarcomas originating from primitive mesenchymal cells. It was first reported in postmenopausal women in 1970, and fewer than 50 postmenopausal patients have been reported to date.

CASE SUMMARY

A 68-year-old multiparous female was admitted to the hospital on October 11, 2023, with the chief complaint of a mass causing vaginal prolapse with incomplete urination that had persisted for 4 months. The vaginal mass was approximately the size of a pigeon egg; after lying down, the vaginal mass retracted. Complete resection was performed, and vaginal pleomorphic RMS was diagnosed based on pathology and immunohistochemical staining features. The patient is currently undergoing chemotherapy. The present study also reviewed the clinical, histological, and immunohistochemical features and latest treatment recommendations for vaginal RMS. Any abnormal vaginal mass should be promptly investigated through pelvic examination and appropriate imaging. The current initial treatment for vaginal RMS is biopsy and primary chemotherapy.

CONCLUSION

When surgery is planned for vaginal RMS, an organ-preserving approach should be considered.

Areas with high HIV prevalence: A spatial analysis of nationwide claims data in Germany

OBJECTIVE

We aimed to identify spatial clusters of high HIV prevalence in Germany.

METHODS

Using nationwide outpatient claims data comprising information of about 88% of the total German population (N = 72 041 683), we examined spatial variations and spatial clusters of high HIV prevalence at the district level (N = 401). People with HIV were identified using the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10 codes) B20, B22, and B24 (HIV disease) documented as 'confirmed'.

RESULTS

Among 72 041 683 people with statutory health insurance in Germany in 2021, 72 636 had diagnosed HIV, which corresponds to a prevalence of 101 per 100 000 individuals (0.10%). Of these, 56 895 were males (78%). At a district level, the HIV prevalence varied by a factor of 32 between 13 in a rural district in Bavaria and 417 per 100 000 individuals in the German capital, Berlin. The spatial autocorrelation coefficient was 0.24 (p < 0.0001, Global Moran's I). Several high-prevalence spatial clusters of different sizes were identified, mostly located in western Germany. The largest cluster comprised eight districts in the southern part of Hesse, including the city of Frankfurt and the city of Mainz in Rhineland-Palatinate. The second cluster consisted of four districts in North Rhine-Westphalia, including the cities of Cologne and Düsseldorf. Two districts in southern Germany (Mannheim and Ludwigshafen) formed the third cluster. Only urban districts were observed in spatial clusters of high HIV prevalence.

CONCLUSIONS

The current study identified for the first time spatial clusters with high HIV prevalence in Germany. This understanding is of particular importance when planning the general and specialized medical care of patients with HIV and to support preventive measures.

Reproductive outcomes following copper‑containing intrauterine device after hysteroscopic lysis for intrauterine adhesions

The present study aimed to investigate the reproductive outcomes of copper-containing intrauterine devices (IUDs) after hysteroscopic lysis in patients with mild to severe intrauterine adhesions (IUAs), according to the American Fertility Society (AFS) classification. Therefore, a prospective randomized controlled study was conducted at the Affiliated Jinhua Hospital of Wenzhou Medical University (Jinhua, China). A total of 173 women with IUAs were initially recruited between January 2020 and June 2021 and were then randomized to the copper-containing IUD group or the no barrier device group. Following hysteroscopic procedure, the fertility and obstetric outcomes were analyzed. Among the 173 patients enrolled, a total of 109 participants completed the study protocol. The results showed that AFS scores were not significantly different between the two groups prior to hysteroscopy. In addition, no statistically significant differences were recorded in pregnancy and live birth rates between the copper-containing IUD and no barrier device groups. Overall, the results of the current study indicated that the copper-containing IUDs had no positive effect on pregnancy and live birth rates in patients with mild to severe IUAs after hysteroscopic adhesiolysis. The present trial was retrospectively registered in the Chinese Clinical Trial Registry on 28th December 2023 (registration no. ChiCTR2300079233).

Evaluation of high dose N- Acetylcysteine on airway inflammation and quality of life outcomes in adults with bronchiectasis: A randomised placebo-controlled pilot study

BACKGROUND

High dose N acetylcysteine (NAC), a mucolytic, anti-inflammatory and antioxidant agent has been shown to significantly reduce exacerbations, and improve quality of life in placebo controlled, double blind randomised (RCT) studies in patients with COPD, and in an open, randomised study in bronchiectasis. In this pilot, randomised, double-blind, placebo-controlled study, we wished to investigate the feasibility of a larger clinical trial, and the anti-inflammatory and clinical benefits of high dose NAC in bronchiectasis.

AIMS

Primary outcome: to assess the efficacy of NAC 2400 mg/day at 6 weeks on sputum neutrophil elastase (NE), a surrogate marker for exacerbations. Secondary aims included assessing the efficacy of NAC on sputum MUC5B, IL-8, lung function, quality of life, and adverse effects.

METHODS

Participants were randomised to receive 2400 mg or placebo for 6 weeks. They underwent 3 visits: at baseline, week 3 and week 6 where clinical and sputum measurements were assessed.

RESULTS

The study was stopped early due to the COVID pandemic. In total 24/30 patients were recruited, of which 17 completed all aspects of the study. Given this, a per protocol analysis was undertaken: NAC (n = 9) vs placebo (n = 8): mean age 72 vs 62 years; male gender: 44% vs 50%; baseline median FEV11.56 L (mean 71.5 % predicted) vs 2.29L (mean 82.2% predicted). At 6 weeks, sputum NE fell by 47% in the NAC group relative to placebo (mean fold difference (95%CI: 0.53 (0.12,2.42); MUC5B increased by 48% with NAC compared with placebo. Lung function, FVC improved significantly with NAC compared with placebo at 6 weeks (mean fold difference (95%CI): 1.10 (1.00, 1.20), p = 0.045. Bronchiectasis Quality of life measures within the respiratory and social functioning domains demonstrated clinically meaningful improvements, with social functioning reaching statistical significance. Adverse effects were similar in both groups.

CONCLUSION

High dose NAC exhibits anti-inflammatory benefits, and improvements in aspects of quality of life and lung function measures. It is safe and well tolerated. Further larger placebo controlled RCT's are now warranted examining its role in reducing exacerbations.

Plasma-Induced 2D Electron Transport at Hetero-Phase Titanium Oxide Interface

Interfaces of metal oxide heterojunctions display a variety of intriguing physical properties that enable novel applications in spintronics, quantum information, neuromorphic computing, and high-temperature superconductivity. One such LaAlO3 /SrTiO3 (LAO/STO) heterojunction hosts a 2D electron liquid (2DEL) presenting remarkable 2D superconductivity and magnetism. However, these remarkable properties emerge only at very low temperatures, while the heterostructure fabrication is challenging even at the laboratory scale, thus impeding practical applications. Here, a novel plasma-enabled fabrication concept is presented to develop the TiO2 /Ti3 O4 hetero-phase bilayer with a 2DEL that exhibits features of a weakly localized Fermi liquid even at room temperature. The hetero-phase bilayer is fabricated by applying a rapid plasma-induced phase transition that transforms a specific portion of anatase TiO2 thin film into vacancy-prone Ti3 O4 in seconds. The underlying mechanism relies on the screening effect of the achieved high-density electron liquid that suppresses the electron-phonon interactions. The achieved "adiabatic" electron transport in the hetero-phase bilayer offers strong potential for low-loss electric or plasmonic circuits and hot electron harvesting and utilization. These findings open new horizons for fabricating diverse multifunctional metal oxide heterostructures as an innovative platform for emerging clean energy, integrated photonics, spintronics, and quantum information technologies.

Clinical Diagnosis of Cervical Lesions Combined with Programmed Death Ligand and miR-124 Detection in Peripheral Blood

Objective

This study aims to analyze the expression of colposcopy combined with PD-L1 (programmed death ligand-1) and miR-124 (microRNA-124) in CC (cervical cancer) and CIN (cervical precancerous lesions), providing insights for clinical screening and diagnosis of these conditions.

Method

A total of 60 patients with suspicious cervical lesions were selected from the gynecological clinic at Jinhua People's Hospital between June 2021 and December 2021. The patients were divided into three groups: LSIL (low-grade squamous intraepithelial lesions), HSIL (high-grade squamous intraepithelial lesions), and no SIL group, with 20 cases per group. This sample distribution ensures a comprehensive representation of different lesion severities. Pathological tissues were collected from each group for immunohistochemistry analysis to assess PD-L1 expression. Peripheral blood samples were also obtained from the patients for PCR analysis to evaluate miR-124 expression. These techniques allowed us to examine the expression levels of PD-L1 and miR-124 in the samples accurately.

Result

The HSIL group exhibited a higher rate of positive PD-L1 expression compared to the LSIL and no lesion groups. Additionally, the expression level of miR-124 was lower in the HSIL group compared to the LSIL and no lesion groups (P < .05). Statistical measures such as means, standard deviations, and P values were used to quantify these differences, providing a more comprehensive understanding of the results.

Conclusions

Combining colposcopy results with the expression of PD-L1 and miR-124 can effectively evaluate precancerous lesions of cervical cancer. This combined approach holds significant clinical implications by potentially enhancing early detection, diagnosis, and treatment strategies for CC and CIN. Further research in this area may lead to improved patient outcomes and contribute to the development of targeted therapies.

TRANSCRIPTOME ANALYSIS REVEALED THE MOLECULAR SIGNATURES OF CISPLATIN-FLUOROURACIL COMBINED CHEMOTHERAPY RESISTANCE IN GASTRIC CANCER

Gastric cancer (GC) is among the top five malignant tumors worldwide in terms of morbidity and death. Chemotherapy is the primary treatment for unresectable or advanced postoperative GC. Chemotherapy resistance developed against cisplatin-fluorouracil (CF) combined chemotherapy is one of the most common clinical issues in patients with GC, leading to poor prognosis. Two different methods were used to analyze GSE14210, and two gene sets were obtained. The first method involved performing the traditional difference analysis (adjusted p<0.05, |log2FC|>=1) by Network Analyst to obtain gene set 1, followed by conducting gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis on the obtained gene set. The second method involved using iDEP to make the weighted gene co-expression network analysis (WGCNA) and performing GO and KEGG enrichment analysis, to obtain gene set 2. Thereafter, the STRING database and Cytoscape were used to construct Protein-Protein Interaction (PPI) networks, screen core clusters, and hub genes of the two gene sets. Furthermore, the hub genes were verified in GSE14210 by the survival analysis method of the Kaplan-Meier plotter database. Finally, we analyzed the mRNA expression of the hub genes by UALCAN and the protein expression of the same by Human Protein Atlas (HPA). Three real hub genes with the same mRNA expression as that of protein were identified, including CENPB, MTA1, and GCNT3. Finally, we performed single gene GO and KEGG enrichment analyses to explore the possible mechanisms of action of these three genes. The mRNA and protein expressions of CENPB, MTA1, and GCNT3 were upregulated in CF-resistant GC patients, and they were significantly associated with bad overall survival (OS). CENPB, MTA1 and GCNT3 are expected to be biomarkers with promising clinical applications as potential therapeutic targets for patients with refractory GC treated with CF combined chemotherapy.

Facile filter cloth brush-coating of large-area uniform silver nanowire conductive films for paper-based heater

Filter cloth brush-coating (FCBC), using soft filter cloth as a brush-coating medium, in conjunction with viscous silver nanowire (AgNW) conductive solution, is used to prepare AgNW conductive films. The density and uniformity of AgNWs deposited on the substrate are controlled by the interplay between the filter cloth aperture, the conductive solution viscosity, and the brush-coating speed. Further, with appropriate AgNW concentration and flow rate, uniform AgNW transparent conductive film with sheet resistance of 18 Ω sq-1and transmittance of 94% at 550 nm is acquired by FCBC. Due to the precise control of the coating process in FCBC, large-area uniform AgNW conductive film fabricated on printing paper has a low non-uniformity factor of 1.2% at a sheet resistance of 19.0 Ω sq-1. The resultant paper-based AgNW film heater shows sensitive and stable heating performance. FCBC shows great potential in producing large-area uniform AgNW films on various substrates.

Reconstructing a long-term water storage-based drought index in the Yangtze River Basin

Drought is a prolonged dry period in the natural climate cycle, and is one of the most costly weather events. The Gravity Recovery and Climate Experiment (GRACE) derived terrestrial water storage anomalies (TWSA) have been widely used to assess drought severity. However, the relatively short cover period of GRACE and GRACE Follow-On limit our knowledge about the characterization and evolution of drought over decades time scale. This study proposes a standardized GRACE reconstructed TWSA index (SGRTI) to assess the drought severity based on a statistical reconstruction method calibrated by GRACE observations. Results show that the SGRTI correlates well with 6-month scale SPI and SPEI, with correlation coefficients reaching 0.79 and 0.81 in the YRB from 1981 to 2019. Soil moisture can capture drought condition like the SGRTI, while cannot further reflect deeper water storage depletion. The SGRTI is also comparable to the SRI and in-situ water level. As a case study for the Yangtze River Basin, its three sub-basins experience more frequent droughts, shorter drought duration, and lower severity drought, as identified by SGRTI during 1992-2019 relative to 1963-1991. The presented SGRTI in this study can provide a valuable supplement to the drought index before the GRACE era.

Amyloid-Gold Nanoparticle Hybrids for Biocompatible Memristive Devices

Biomolecular materials offer tremendous potential for the development of memristive devices due to their low cost of production, environmental friendliness, and, most notably, biocompatibility. Herein, biocompatible memristive devices based on amyloid-gold nanoparticle hybrids have been investigated. These memristors demonstrate excellent electrical performance, featuring an ultrahigh R_off/R_on ratio (>10⁷), a low switching voltage (<0.8 V), and reliable reproducibility. Additionally, the reversible transition from threshold switching to resistive switching mode was achieved in this work. The arrangement of peptides in amyloid fibrils endows the surface polarity and phenylalanine packing, which provides channels for the migration of Ag ions in the memristors. By modulating voltage pulse signals, the study successfully imitates the synaptic behavior of excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), and the transition from short-term plasticity (STP) to long-term plasticity (LTP). More interestingly, Boolean logic standard cells were designed and simulated using the memristive devices. The fundamental and experimental results of this study thus offer insights into the utilization of biomolecular materials for advanced memristive devices.

Overcoming Ion Transport Barrier by Plasma Heterointerface Engineering: Epitaxial Titanium Carbonitride on Nitrogen-Doped TiO2 for High-Performance Sodium-Ion Batteries

Anatase TiO₂ is a promising anode material for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) due to its high specific capacity, low cost, and excellent cycle stability. However, low electrical conductivity and poor Na⁺ ion transport in TiO₂ limit its practical applications. Here, substantially boosted Na⁺ ion transport and charge transfer kinetics are demonstrated by constructing a near-ideal non-rectifying titanium carbonitride/nitrogen-doped TiO₂ (TiC_x N_{1- x} /N-TiO₂ ) heterostructure. Owing to the fast plasma effects and metastable hybrid phases, the TiC_x N_{1- x} is epitaxially grown on TiO₂ . Energy band engineering at the interface induces high electron densities and a strong built-in electric field, which lowers the Na⁺ diffusion barrier by a factor of 1.7. As a result, the TiC_x N_{1- x} /N-TiO₂ electrode exhibits excellent electrochemical performance. The reversible specific capacities at rates of 0.1 and 10 C reach 312.3 and 173.7 mAh g^-1 , respectively. After 600 cycles of charge and discharge at 10 C, the capacity retention rate is 98.7%. This work discovers an effective non-equilibrium plasma-enabled process to construct heterointerfaces that can enhance Na⁺ ion transport and provides generic guidelines for the design of heterostructures for a broader range of energy storage, separation, and other devices that rely on controlled ionic transport.

Is catalase an effective additive to alleviate oxidative stress during cryopreservation of zebrafish sperm at the repository level?

The goal of this study was to investigate whether supplementation of cryoprotective medium with catalase (CAT), an antioxidation enzyme, is efficient for zebrafish sperm cryopreservation from the viewpoint of high-throughput genetic repository operations. Three cryoprotectants (10%, v/v), dimethylacetamide (DMA), dimethylformamide (DMF), and methanol were used. The objectives were to evaluate the effects of CAT on sperm motility, plasma membrane integrity, and concentration for: 1) fresh sperm at equilibration up to 60 min; 2) post-thaw sperm after cooling at 10, 20, and 40 °C/min), and 3) post-thaw fertilization and embryo survival rates. Catalase addition did not improve sperm motility, regardless of the cryoprotectants added. After 10-min exposure to DMA or methanol, membrane integrity was significantly decreased (70-75%) compared to controls. With catalase, sperm cells maintained membrane integrity and after 50 min equilibration, cell concentrations were maintained with CAT compared to cryoprotectant-only test groups. However, after cryopreservation and thawing, CAT did not affect the outcome of motility, membrane integrity, cell concentration, fertilization, or embryo survival assays. Analysis of cooling rates also indicated that CAT did not affect 3-hpf fertilization or 24-hpf survival rates. Overall, addition of CAT could provide some protection of sperm from oxidative stress before freezing, but not after thawing. We propose that decisions concerning routine use of CAT for repositories, especially those handling tens of thousands of frozen samples per year, would depend on whether efficient high-throughput operation, or specific research questions are programmatic goals.

Temporal and Concentration Effects of Methanol on Cryopreservation of Zebrafish (Danio rerio) Sperm

We evaluated the cryoprotective effects of methanol on zebrafish sperm at different concentrations, exposure times, and stages during cryopreservation. Samples were collected by crushing of dissected testes or abdominal stripping. After exposure to 0%, 2%, 5%, 8%, and 10% methanol for 0-11 min, fresh sperm (1 × 106 cells/mL) did not show changes in plasma membrane integrity (measured by flow cytometer), but cell size changes (light scatter) were observed after exposure to 8% or 10%. After exposure for 0-60 min, fresh sperm (1 × 108 cells/mL) did not show significant changes in survival or membrane integrity. Sperm cryopreserved in 5%, 8%, and 10% methanol showed high post-thaw survival, in 5% and 8% showed high post-thaw motility, and in 5% showed highest post-thaw membrane integrity compared to other concentrations between 0% and 10%. Within 0-60 min after thawing, no significant differences in cell survival and membrane integrity were found for any concentration (p ≥ 0.269). Comparison of 5% and 8% methanol for dissected testes (n = 20) revealed no difference in post-thaw motility, membrane integrity, cell survival, fertilization, or hatching, embryo viability; for stripped sperm (n = 10), no differences were observed in post-thaw membrane integrity, fertilization, and embryo viability, however, higher motility and survival were detected in 5% than in 8% methanol. Thus, a concentration of 5% methanol seems most suitable for cryopreserving zebrafish sperm based on post-thaw survival and motility.

Relative Effectiveness of Selenite Cystine Broth, Tetrathionate Broth, and Rappaport-Vassiliadis Medium for Recovery of Salmonella spp. from Raw Flesh, Highly Contaminated Foods, and Poultry Feed: Collaborative Study

A collaborative study was performed in 18 laboratories to validate use of Rappaport-Vassiliadis (RV) medium in the standard culture method for recovery of Salmonella spp. from raw, highly contaminated foods and poultry feed. RV medium made from its individual ingredients and incubated at 42�C was compared with selenite cystine (SC) broth incubated at 35�C and tetrathionate (TT) broth incubated at 35� and 43�C for effectiveness in recovery of Salmonella spp. Four artificially contaminated foods (oysters, frog legs, mushrooms, and shrimp) and poultry feed and one naturally contaminated food (chicken) were analyzed. The artificially contaminated foods were inoculated with single serovars of Salmonella at target levels of 0.04 colony-forming units (CFU)/g for the low level and 0.4 CFU/g for the high level. For analysis of 1125 test portions, RV medium (42�C) recovered Salmonellairom 409 test portions; TT (43�C), from 368 test portions; TT (35�C), from 310 test portions; and SC (35�C), from 334 test portions. Overall, RV medium was comparable with or better than other selective enrichments for recovery of Salmonella from the foods in this study, except mushrooms. From mushrooms, SC broth (35�C) recovered more positive test portions than did RV medium (42�C) and TT broth (43�C). The method for detection of Salmonella in raw, highly contaminated foods and

A Strategy for Sperm Cryopreservation of Atlantic Salmon, Salmo salar, for Remote Commercial-scale High-throughput Processing

Sperm cryopreservation is an essential tool for long-term storage of genetic resources for aquaculture fishes. The goal of this study was to develop an efficient and streamlined protocol for high-throughput processing for sperm cryopreservation in Atlantic salmon, Salmo salar. The objectives were to evaluate: 1) osmolality of blood serum for determining extender osmolality; 2) effects of extenders for fresh sperm dilution and refrigerated storage; 3) effects of methanol and dimethyl sulfoxide (DMSO) on fresh sperm motility, and 4) motility and fertility after thawing. In this study, sperm samples were collected at a hatchery site in Canada, and shipped to a freezing site located 2200 miles (3550 km) away in the United States. Evaluation of three extenders indicated that Mounib solution was suitable for diluting dry sperm for sample processing. Ten percent of methanol or DMSO was less toxic to sperm cells than was 15% within 30 min. Further testing with methanol at 5, 10, and 15%, and sperm solution:extender dilutions (v:v) of 1:1, 1:3, 1:19 (at concentrations of ~5×10⁷; 3×10⁸, and 1×10⁹ cells/mL) indicated that methanol at 5% and 10% showed less toxicity to fresh sperm within 1 hr at sperm: extender dilutions of 1:1 and 1:3. Post-thaw motility of sperm cryopreserved with 10% methanol was significantly higher than that with 10% DMSO, and fertility reflected those results (0-1% in DMSO vs. 38-55% in methanol). Further evaluation of sperm cryopreservation with 10 and 15% methanol at sperm dilution ratios of 1:1, 1:3, 1:19 indicated post-thaw motility in 10% methanol was significantly higher than that in 15% methanol, and post-thaw fertility in 10% methanol at 1:1 and 1:3 dilution ratios had fertilization rates similar to that of fresh sperm controls. Sperm samples from 12 males cryopreserved with 10% methanol showed male-to-male variation in post-thaw motility (0-36%). Overall, a simplified standard protocol was established for cryopreservation of shipped sperm of Atlantic salmon using extender without egg yolk and yielded satisfactory post-thaw motility and fertilization rates. This procedure can be readily adopted by aquaculture facilities to take advantage of high-throughput cryopreservation capabilities at remote service centers. Most importantly, this approach lays the groundwork for an alternative commercial model for commercial-scale production, quality control and development of industrial standards. Control of male variability and sperm quality remain important considerations for future work.

3-D printing provides a novel approach for standardization and reproducibility of freezing devices

Cryopreservation has become an important and accepted tool for long-term germplasm conservation of animals and plants. To protect genetic resources, repositories have been developed with national and international cooperation. For a repository to be effective, the genetic material submitted must be of good quality and comparable to other submissions. However, due to a variety of reasons, including constraints in knowledge and available resources, cryopreservation methods for aquatic species vary widely across user groups which reduces reproducibility and weakens quality control. Herein we describe a standardizable freezing device produced using 3-dimensional (3-D) printing and introduce the concept of network sharing to achieve aggregate high-throughput cryopreservation for aquatic species. The objectives were to: 1) adapt widely available polystyrene foam products that would be inexpensive, portable, and provide adequate work space; 2) develop a design suitable for 3-D printing that could provide multiple configurations, be inexpensive, and easy to use, and 3) evaluate various configurations to attain freezing rates suitable for various common cryopreservation containers. Through this approach, identical components can be accessed globally, and we demonstrated that 3-D printers can be used to fabricate parts for standardizable freezing devices yielding relevant and reproducible cooling rates across users. With standardized devices for freezing, methods and samples can harmonize into an aggregated high-throughput pathway not currently available for aquatic species repository development.

Vitrification as an Alternative Approach for Sperm Cryopreservation in Marine Fishes

The Southern Flounder Paralichthys lethostigma is a high-value species and a promising aquaculture candidate. Because sperm volume can be limited in this species (<500 μL), new sperm cryopreservation methods need to be evaluated. Vitrification is an alternative to conventional slow-rate freezing, whereby small volumes are cryopreserved at high cooling rates (>1,000°C/min). The goal of this work was to develop a standardized approach for vitrification of Southern Flounder sperm. The specific objectives were to (1) evaluate thawing methods and vitrification solutions, (2) evaluate the postthaw membrane integrity of sperm vitrified in different cryoprotectant solutions, (3) examine the relationship between membrane integrity and motility, and (4) evaluate the ability of vitrified sperm to fertilize eggs. From the vitrification solutions tested, the highest postthaw motility (28 ± 9% [mean ± SD]) and membrane integrity (11 ± 4%) was observed for 20% ethylene glycol plus 20% glycerol. There was no significant difference in postthaw motility of sperm thawed at 21°C or at 37°C. Fertilization from vitrified sperm in one trial yielded the same fertilization rate (50 ± 20%) as the fresh sperm control, while the sperm from the other two males yielded 3%. This is the first report of fertilization by vitrified sperm in a marine fish. Vitrification can be simple, fast, inexpensive, performed in the field, and, at least for small fishes, offers an alternative to conventional cryopreservation. Because of the minute volumes needed for ultrarapid cooling, vitrification is not presently suited as a production method for large fishes. Vitrification can be used to reconstitute lines from valuable culture species and biomedical models, conserve mutants for development of novel lines for ornamental aquaculture, and transport frozen sperm from the field to the repository to expand genetic resources.

Abstract P1-12-07: Phase Ib/II single-arm trial evaluating the combination of everolimus, lapatinib and capecitabine for the treatment of patients with HER2-positive metastatic breast cancer with progression in the CNS after trastuzumab (TRIO-US B-09)

Background: Improving outcomes for patients with HER2+ CNS metastases remains an unmet clinical need. Lapatinib (L) plus capecitabine (C) yields a 20% objective response rate (ORR) in the CNS in patients with previously treated HER2+ breast cancer brain metastases (Lin N, Clin Cancer Res 2009). Everolimus (E), an oral inhibitor of the mammalian target of rapamycin (mTOR), penetrates into the CNS in murine xenograft models (Meikle L, J Neurosci 2008). TRIO-US B09 is an investigator-initiated trial evaluating the safety and clinical activity of the novel combination of L+C+E for the treatment of patients with HER2+ breast cancer brain metastases.

Methods: Patients with trastuzumab-pretreated, HER2+ metastatic breast cancer (MBC) with progression of disease (PD) in the brain and a measurable brain lesion participated. Patients were excluded if they had a prior mTOR inhibitor or an ECOG PS&gt;2. Prior L and/or C, and prior surgery and/or radiation to the brain were allowed. The primary endpoint was CNS ORR at 12 weeks (cycle 3) by RECIST 1.1. Secondary endpoints included safety, progression-free survival, overall survival and extra-CNS ORR. To test the safety of the combination of L+C+E, a 3+3 dose escalation phase was conducted (starting doses: L 1000 mg QD, E 5 mg QD, C: 750 mg/m2 BID d1-14). Treatment was given Q21 days. Patients were evaluated for dose limiting toxicities during C1. Tumor imaging was conducted every 3 cycles. MRI of the brain was performed every 2 cycles through cycle 6 and then every 3 cycles. Neurological symptom assessment was conducted on day 1 of every cycle. Study participants continued to receive treatment until PD, unacceptable toxicity or withdrawal of consent for 12 mos.

Results: Nineteen patients were enrolled at 11 sites in the US and treated with at least one dose of study drug. Of 18 patients with data available, median age was 58.5 (45-68), median number of systemic therapies for MBC was 2 (0-6), and 94.4% had prior radiation and/or surgical resection of brain metastases. 10 patients participated in the dose escalation phase of the study. The maximum tolerated doses were determined to be L 1000 mg QD, E 10 mg QD + C 1000 mg/m2BID days 1-14; however, given tolerability concerns, dose expansion proceeded with Cohort 2 dose for C (750 mg/m2 BID d1-14). Of 17 eligible patients with imaging results available to date, 2 (12%) had a partial response in the CNS at week 12, one of whom continues on study (currently in cycle 13). Stable disease was observed in 7 patients. The most common grade 3/4 adverse events (AE) (CTCAE v4.0) related to E and/or L in 18 treated patients were anorexia (5.5%), dehydration (5.5%), diarrhea (17%), fatigue (5.5%), fever (5.5%) hyperglycemia (5.5%), hypokalemia (11%), and oral mucositis (17%).

Conclusions: This is the first report of this regimen for patients with HER2+ MBC to the brain. This regimen is generally well-tolerated and shows promising activity in the CNS of heavily pretreated patients. Final efficacy and toxicity analyses for all 19 patients will be presented.

Citation Format: Hurvitz SA, Martinez DA, Singh R, Taguchi J, Chan D, Dichmann R, Castrellon A, Barstis J, Hu E, Berkowitz J, Mani A, DiCarlo B, Smalberg I, Hobbs E, Slamon DJ. Phase Ib/II single-arm trial evaluating the combination of everolimus, lapatinib and capecitabine for the treatment of patients with HER2-positive metastatic breast cancer with progression in the CNS after trastuzumab (TRIO-US B-09) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-12-07.

Cryopreservation in fish: current status and pathways to quality assurance and quality control in repository development

Cryopreservation in aquatic species in general has been constrained to research activities for more than 60 years. Although the need for application and commercialisation pathways has become clear, the lack of comprehensive quality assurance and quality control programs has impeded the progress of the field, delaying the establishment of germplasm repositories and commercial-scale applications. In this review we focus on the opportunities for standardisation in the practices involved in the four main stages of the cryopreservation process: (1) source, housing and conditioning of fish; (2) sample collection and preparation; (3) freezing and cryogenic storage of samples; and (4) egg collection and use of thawed sperm samples. In addition, we introduce some key factors that would assist the transition to commercial-scale, high-throughput application.

Simulation modeling of high-throughput cryopreservation of aquatic germplasm: a case study of blue catfish sperm processing

Emerging commercial-level technology for aquatic sperm cryopreservation has not been modeled by computer simulation. Commercially available software (ARENA, Rockwell Automation, Inc. Milwaukee, WI) was applied to simulate high-throughput sperm cryopreservation of blue catfish (Ictalurus furcatus) based on existing processing capabilities. The goal was to develop a simulation model suitable for production planning and decision making. The objectives were to: 1) predict the maximum output for 8-hr workday; 2) analyze the bottlenecks within the process, and 3) estimate operational costs when run for daily maximum output. High-throughput cryopreservation was divided into six major steps modeled with time, resources and logic structures. The modeled production processed 18 fish and produced 1164 ± 33 (mean ± SD) 0.5-ml straws containing one billion cryopreserved sperm. Two such production lines could support all hybrid catfish production in the US and 15 such lines could support the entire channel catfish industry if it were to adopt artificial spawning techniques. Evaluations were made to improve efficiency, such as increasing scale, optimizing resources, and eliminating underutilized equipment. This model can serve as a template for other aquatic species and assist decision making in industrial application of aquatic germplasm in aquaculture, stock enhancement, conservation, and biomedical model fishes.

A quality assurance initiative for commercial-scale production in high-throughput cryopreservation of blue catfish sperm

Cryopreservation of fish sperm has been studied for decades at a laboratory (research) scale. However, high-throughput cryopreservation of fish sperm has recently been developed to enable industrial-scale production. This study treated blue catfish (Ictalurus furcatus) sperm high-throughput cryopreservation as a manufacturing production line and initiated quality assurance plan development. The main objectives were to identify: (1) the main production quality characteristics; (2) the process features for quality assurance; (3) the internal quality characteristics and their specification designs; (4) the quality control and process capability evaluation methods, and (5) the directions for further improvements and applications. The essential product quality characteristics were identified as fertility-related characteristics. Specification design which established the tolerance levels according to demand and process constraints was performed based on these quality characteristics. Meanwhile, to ensure integrity throughout the process, internal quality characteristics (characteristics at each quality control point within process) that could affect fertility-related quality characteristics were defined with specifications. Due to the process feature of 100% inspection (quality inspection of every fish), a specific calculation method, use of cumulative sum (CUSUM) control charts, was applied to monitor each quality characteristic. An index of overall process evaluation, process capacity, was analyzed based on in-control process and the designed specifications, which further integrates the quality assurance plan. With the established quality assurance plan, the process could operate stably and quality of products would be reliable.

Hyperglycemia and prostate cancer recurrence in men treated for localized prostate cancer

BACKGROUND

Obesity is consistently linked with prostate cancer (PCa) recurrence and mortality, though the mechanism is unknown. Impaired glucose regulation, which is common among obese individuals, has been hypothesized as a potential mechanism for PCa tumor growth. In this study, we explore the relationship between serum glucose at time of treatment and risk of PCa recurrence following initial therapy.

METHODS

The study group comprised 1734 men treated with radical prostatectomy (RP) or radiation therapy (RT) for localized PCa between 2001-2010. Serum glucose levels closest to date of diagnosis were determined. PCa recurrence was determined based on PSA progression (nadir PSA+2 for RT; PSA≥0.2 for RP) or secondary therapy. Multivariate Cox regression was performed to determine whether glucose level was associated with biochemical recurrence after adjusting for age, race, body mass index, comorbidity, diagnosis of diabetes, Gleason Sum, PSA, treatment and treatment year.

RESULTS

Recurrence was identified in 16% of men over a mean follow-up period of 41 months (range 1-121 months). Those with elevated glucose (≥100 mg/dl) had a 50% increased risk of recurrence (HR 1.5, 95% CI: 1.1-2.0) compared with those with a normal glucose level (<100 mg/dl). This effect was seen in both those undergoing RP (HR 1.9, 95% CI: 1.0-3.6) and those treated with RT (HR 1.4, 95% CI: 1.0-2.0).

CONCLUSIONS

Glucose levels at the time of PCa diagnosis are an independent predictor of PCa recurrence for men undergoing treatment for localized disease.

Outlook for development of high-throughput cryopreservation for small-bodied biomedical model fishes

With the development of genomic research technologies, comparative genome studies among vertebrate species are becoming commonplace for human biomedical research. Fish offer unlimited versatility for biomedical research. Extensive studies are done using these fish models, yielding tens of thousands of specific strains and lines, and the number is increasing every day. Thus, high-throughput sperm cryopreservation is urgently needed to preserve these genetic resources. Although high-throughput processing has been widely applied for sperm cryopreservation in livestock for decades, application in biomedical model fishes is still in the concept-development stage because of the limited sample volumes and the biological characteristics of fish sperm. High-throughput processing in livestock was developed based on advances made in the laboratory and was scaled up for increased processing speed, capability for mass production, and uniformity and quality assurance. Cryopreserved germplasm combined with high-throughput processing constitutes an independent industry encompassing animal breeding, preservation of genetic diversity, and medical research. Currently, there is no specifically engineered system available for high-throughput of cryopreserved germplasm for aquatic species. This review is to discuss the concepts and needs for high-throughput technology for model fishes, propose approaches for technical development, and overview future directions of this approach.

Outlook for development of high-throughput cryopreservation for small-bodied biomedical model fishes

With the development of genomic research technologies, comparative genome studies among vertebrate species are becoming commonplace for human biomedical research. Fish offer unlimited versatility for biomedical research. Extensive studies are done using these fish models, yielding tens of thousands of specific strains and lines, and the number is increasing every day. Thus, high-throughput sperm cryopreservation is urgently needed to preserve these genetic resources. Although high-throughput processing has been widely applied for sperm cryopreservation in livestock for decades, application in biomedical model fishes is still in the concept-development stage because of the limited sample volumes and the biological characteristics of fish sperm. High-throughput processing in livestock was developed based on advances made in the laboratory and was scaled up for increased processing speed, capability for mass production, and uniformity and quality assurance. Cryopreserved germplasm combined with high-throughput processing constitutes an independent industry encompassing animal breeding, preservation of genetic diversity, and medical research. Currently, there is no specifically engineered system available for high-throughput of cryopreserved germplasm for aquatic species. This review is to discuss the concepts and needs for high-throughput technology for model fishes, propose approaches for technical development, and overview future directions of this approach.

High-throughput cryopreservation of spermatozoa of blue catfish (Ictalurus furcatus): Establishment of an approach for commercial-scale processing

Hybrid catfish created by crossing of female channel catfish (Ictalurus punctatus) and male blue catfish (Ictalurus furcatus) are being used increasingly in foodfish aquaculture because of their fast growth and efficient food conversion. However, the availability of blue catfish males is limited, and their peak spawning is at a different time than that of the channel catfish. As such, cryopreservation of sperm of blue catfish could improve production of hybrid catfish, and has been studied in the laboratory and tested for feasibility in a commercial dairy bull cryopreservation facility. However, an approach for commercially relevant production of cryopreserved blue catfish sperm is still needed. The goal of this study was to develop practical approaches for commercial-scale sperm cryopreservation of blue catfish by use of an automated high-throughput system (MAPI, CryoBioSystem Co.). The objectives were to: (1) refine cooling rate and cryoprotectant concentration, and evaluate their interactions; (2) evaluate the effect of sperm concentration on cryopreservation; (3) refine cryoprotectant concentration based on the highest effective sperm concentration; (4) compare the effect of thawing samples at 20 or 40°C; (5) evaluate the fertility of thawed sperm at a research scale by fertilizing with channel catfish eggs; (6) test the post-thaw motility and fertility of sperm from individual males in a commercial setting, and (7) test for correlation of cryopreservation results with biological indices used for male evaluation. The optimal cooling rate was 5°C/min (Micro Digitcool, IMV) for high-throughput cryopreservation using CBS high-biosecurity 0.5-ml straws with 10% methanol, and a concentration of 1×10(9)sperm/ml. There was no difference in post-thaw motility when samples were thawed at 20°C for 40s or 40°C for 20s. After fertilization, the percentage of neurulation (Stage V embryos) was 80±21%, and percentage of embryonic mobility (Stage VI embryo) was 51±22%. There was a significant difference among the neurulation values produced by thawed blue catfish sperm, fresh blue catfish sperm (P=0.010) and channel catfish sperm (P=0.023), but not for Stage VI embryos (P≥0.585). Cryopreserved sperm from ten males did not show significant variation in post-thaw motility or fertility at the neurulation stage. This study demonstrates that the protocol established for high-throughput cryopreservation of blue catfish sperm can provide commercially relevant quantities and quality of sperm with stable fertility for hybrid catfish production and provides a model for establishment of commercial-scale approaches for other aquatic species.

p38 mitogen-activated protein kinase targets the production of proinflammatory endothelial microparticles

BACKGROUND

Endothelial microparticles (EMPs) are irregularly shaped membrane fragments shed into the circulation in patients with vascular diseases, and may themselves act to enhance the endothelial response to inflammation. On the basis of the importance of p38 mitogen-activated protein kinase (MAPK) in endothelial responses to inflammatory stimuli, we sought to define the role of p38 in EMP generation and function.

METHODS

Microparticle generation from cultures of human aortic endothelial cells (hAECs) treated with tumor necrosis factor-alpha (TNF-alpha) and p38 inhibition was quantified via multiple modalities. The response of target endothelial cells was assessed by treatment of cells with EMPs generated under various conditions.

RESULTS

Inhibition of p38 in hAECs, using pharmacologic agents, resulted in a 50% reduction of TNF-alpha-induced EMPs. Importantly, suppression of microparticles was specific to p38 MAPK pathways. EMPs triggered by TNF-alpha activation induced an approximately four-fold increase in soluble intercellular adhesion molecule-1 (sICAM-1) release from targeted cells. However, inhibition of p38 MAPK in the targeted cell prior to EMP treatment did not alter the sICAM1 response.

CONCLUSIONS

Our findings implicate p38 MAPK signaling as significant and selective in the formation and maturation of EMPs. EMPs elicited a proinflammatory response from targeted hAECs that was dependent on the conditions under which EMPs were generated. However, our results imply a unidirectional model in which p38 MAPK is critical at the source of microparticle formation, but not the target cell response to EMPs. These findings indicate a novel mechanism by which p38 inhibition may offer therapeutic benefit in vivo via direct inhibition of EMP formation.

Phosphodiesterase type 2 and the homeostasis of cyclic GMP in living thalamic neurons

The ubiquitous second messenger cyclic GMP (cGMP) is synthesized by soluble guanylate cyclases in response to nitric oxide (NO) and degraded by phosphodiesterases (PDE). We studied the homeostasis of cGMP in living thalamic neurons by using the genetically encoded fluorescence resonance energy transfer sensor Cygnet, expressed in brain slices through viral gene transfer. Natriuretic peptides had no effect on cGMP. Basal cGMP levels decreased upon inhibition of NO synthases or soluble guanylate cyclases and increased when PDEs were inhibited. Single cell RT-PCR analysis showed that thalamic neurons express PDE1, PDE2, PDE9, and PDE10. Basal cGMP levels were increased by the PDE2 inhibitors erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA) and BAY60-7550 but were unaffected by PDE1 or PDE10 inhibitors. We conclude that PDE2 regulates the basal cGMP concentration in thalamic neurons. In addition, in the presence of 3-isobutyl-1-methylxanthine (IBMX), cGMP still decreased after application of a NO donor. Probenecid, a blocker of cGMP transporters, had no effect on this decrease, leaving PDE9 as a possible candidate for decreasing cGMP concentration. Basal cGMP level is poised at an intermediate level from which it can be up or down-regulated according to the cyclase and PDE activities.

Phase II study of docetaxel (D) plus bevacizumab (B) in Her/2 negative metastatic breast carcinoma (MBC)

13047

Background: Taxol+Bevacizumab (B) has clinical activity in Her/2 negative chemotherapy naive MBC with a PFS (11.4 mo), RR (29.9%), and OS (28.4 mo). We are conducting a single arm Phase 2 trial to assess the efficacy of Docetaxel (D)+B. Primary endpoint: time to progression. Secondary endpoints: response rate (CR + PR), response duration, overall survival and safety. Methods: Eligibility criteria: MBC with no prior therapy; Her/2 negative by FISH, ECOG PS 0 or 1; measurable disease by RECIST, Hgb ≥ 9 g/dL, ANC ≥ 1.5 × 109/L, Platelet count ≥ 100 × 109/L, Creatinine ≤ 2.0 mg/dL, Total bilirubin ≤ 1.0 × upper limit of normal, no CNS metastasis, no MI or stroke within 6 mo, no GI perforation, no major surgery within 28 d, and no bleeding diathesis or coagulopathy. Pts receive B 15 mg/kg IV and D 75 mg/m2 IV Q 3 wk. Response assessed radiographically Q 3 cycles. Treatment is until disease progression or unacceptable toxicity. Results: Since Apr 2005, 43 of the planned 75 pts have been enrolled. 21 pts have had at least one assessment resulting in approximately 40% response rate. Common Gr3/4 AE’s have been neutropenia, febrile neutropenia, hypertension. Gr3 LVEF decline seen in one pt. No treatment related deaths occurred. Conclusions: D+ B is well tolerated, with no new safety concerns and manageable toxicities. D+B appears active in MBC. Updated efficacy and safety data will be presented. Study supported by Genentech, Inc. San Francisco, CA.

No significant financial relationships to disclose.

Enhanced degradation efficiency of toluene using titania/silica photocatalysis as a regeneration process

Three kinds of titania/silica pellets were prepared using the sol-gel method with surface areas of 50.4 m2 g(-1), 421.1 m2 x g(-1) and 89.1 m2 x g(-1). An annular reactor was designed and built to determine the degradation efficiency of toluene and to investigate the relationship between the adsorption and desorption-photocatalytic processes. Surface area is an important factor influencing the adsorption-photocatalytic efficiency. Higher surface areas of pellets contribute to high rates of conversion of toluene. Un-reacted toluene and reaction intermediates accumulating on their surface deactivated the titania/silica catalyst. To overcome this problem, the adsorption and regeneration process were alternated in a dual reactor system. Connecting or disconnecting the toluene feed gas enabled one reactor to adsorb toluene, while the second reactor was regenerated by photocatalysis. Using UV irradiation and titania/silica pellets with high BET surface area (421.1 m2 x g(-1)), the alternating adsorption/regeneration processes kept the degradation efficiency of toluene at 90% after 8 hours operation. By improving the adsorption-photocatalysis efficiency, and minimising the generation and accumulation of intermediate on the surface of pellets, the method extended catalyst life and maintained a high degradation efficiency of toluene.

An aldol-based approach to the asymmetric synthesis of L-callipeltose, the deoxyamino sugar of L-callipeltoside A

[reaction: see text] The L-callipeltose subunit of L-callipeltoside A has been synthesized in 10 steps and 13% overall yield from D-threonine. The key steps are a highly diastereoselective Felkin anti aldol addition to a methyl ketone and a selective methylation of a secondary alcohol in the presence of a secondary carbamate.

Molecular cloning and characterization of profilin-3: a novel cytoskeleton-associated gene expressed in rat kidney and testes

Profilin is a small actin-binding protein that is involved in diverse functions such as maintaining cell structure integrity, cell mobility, tumor cell metastasis, as well as growth factor signal transduction. In this paper, we describe the molecular cloning and characterization of a novel form of profilin, termed profilin-3, from rat kidney using a PCR-based procedure for isolating tissue-specific genes. The profilin-3 cDNA encoded 137 amino acids, and it shared extensive homology to profilin-1 and profilin-2 from mice and humans. More strikingly, the expression of profilin-3 was highly selective, and its mRNA was only found in the kidney and to a much lesser extent in the testis. The size of the mRNA for profilin-3 in the testis was 1.2 kb, while in kidney it was approximately 4.4-5 kb, suggesting the presence of tissue-specific transcription from different promoters. In addition, we also found that the expression of profilin-3 mRNA was significantly elevated in two types of renal diseases: diabetic nephropathy (db/db mice) and polycystic kidney diseases (cpk mice). Similar to profilin-1 and profilin-2, profilin-3 was localized in the cytoplasmic domain. Furthermore, it was capable of interacting with actin and poly-L-proline in an in vitro assay as well as in transfected cells. These results strongly suggest that, contrary to the ubiquitous presence of profilin-1 and profilin-2, there is a tissue-specific form of these cytoskeleton-regulatory proteins and that the kidney/testes-specific profilin-3 may play a unique role in renal and/or reproductive functions.

Pilot study of prevalence of Parkinson's disease in Australia

Parkinson's disease is a common neurological disease and its prevalence increases with age. Because of an ageing population and changing environment compared to the last epidemiological study done in Australia over 30 years ago, we have conducted a door-to-door pilot survey which looked at the latest prevalence as well as putative risk factors in a random population. We used a two-phase investigation method (screening followed by detailed examination) in a random community sample of 2,820 households (with 527 individuals aged 55 and over) along with 203 residents in aged care facilities (single-phase examination for residents aged 55 and above) in the Randwick area of Sydney, New South Wales. We had a 75% participation rate in the community and a 94% in the aged care facilities. The results of the survey in this sample of 730 subjects indicated that the crude prevalence of Parkinson's disease was between 3.6 and 4.9% (higher in the aged care facilities). The putative risk factors positively identified using chi-square method were 'family history' (p < 0.01) and 'exposure to chemicals at work or in surrounding environment' (p < 0.05). The age-adjusted prevalence rate of Parkinson's disease revealed at least a 42.5% increase in the disease compared to 1966. We conclude that there may be an increase in the disease in Australia due to ageing and other risk factors.

Rapid isolation of tissue-specific genes from rat kidney

A systematic effort to isolate kidney-specific genes was performed using recently described PCR-select methodology. Using this technique, a kidney-specific mini-gene library was generated and a number of kidney-specific genes that share significant homology to previously characterized kidney genes from rats and other species were isolated. These included three renal-specific transporters (an ADH water channel, the anion transporters RST and ROAT1), a cell adhesion molecule (K-cadherin) and a kidney-specific protein upregulated in renal carcinoma (DD96). In addition, we isolated two novel genes from a rat kidney. One of the genes shares limited homology to rat profilin-1 while the other did not share any similarity to genes in the Genbank. Northern blot analysis revealed that the mRNA for each of these genes is expressed in a highly kidney-restricted fashion. Our results suggested that tissue-specific genes can be rapidly isolated and characterized using PCR-select techniques and this methodology may be generally applicable to isolate specific genes from a variety of tissues.

A quantum dot single-photon turnstile device

Quantum communication relies on the availability of light pulses with strong quantum correlations among photons. An example of such an optical source is a single-photon pulse with a vanishing probability for detecting two or more photons. Using pulsed laser excitation of a single quantum dot, a single-photon turnstile device that generates a train of single-photon pulses was demonstrated. For a spectrally isolated quantum dot, nearly 100% of the excitation pulses lead to emission of a single photon, yielding an ideal single-photon source.

Mutations that alter the higher-order structure of its 5' untranslated region affect the stability of chloroplast rps7 mRNA

In this paper, we examine the effects of mutations in the 5'UTR of the chloroplast rps7 transcript of Chlamydomonas reinhardtii that reduce the stability of the mRNA. Five point mutants in the rps7 5'UTR were selected on the basis of their failure to accumulate reporter mRNA in Escherichia coli. Each of these mutations produces alterations in the predicted higher-order structures of the rps7 5'UTR that destabilize the mRNA. Cis-acting suppressors of these mutations have been selected in E. coli and in the C. reinhardtii chloroplast that restore message stability and function. No differences in RNA melting and reannealing profiles have been observed between wild type, original mutant, and suppressor 5'UTRs transcribed in vitro. Proteins of 32 kDa and 47 kDa that bind to the wild-type rps7 5'UTR are not detected by UV cross-linking assays performed with any of the mutant rps7 5'UTRs. However, binding of the 32-kDa protein is restored in the six suppressor mutants examined. This suggests that the 32-kDa protein may be involved in protecting the rps7 5'UTR and the attached coding region from digestion by ribonucleases. Alternatively, the binding site for the 32-kDa protein may be independently lost in the rearranged tertiary structure of the mutant 5'UTR that exposes the RNA to degradation and is restored in the suppressor mutants.