Enhanced anaerobic digestion performance and sludge filterability by membrane microaeration for anaerobic membrane bioreactor application

Slow dissolution/hydrolysis of insoluble/macromolecular organics and poor sludge filterability restrict the application potential of anaerobic membrane bioreactor (AnMBR). Bubble-free membrane microaeration was firstly proposed to overcome these obstacles in this study. The batch anaerobic digestion tests feeding insoluble starch and soluble peptone with and without microaeration showed that microaeration led to a 65.7-144.8% increase in methane production and increased critical flux of microfiltration membrane via driving the formation of large sludge flocs and the resultant improvement of sludge settleability. The metagenomic and bioinformatic analyses showed that microaeration significantly enriched the functional genes and bacteria for polysaccharide and protein hydrolysis, microaeration showed little negative effects on the functional genes involved in anaerobic metabolisms, and substrate transfer from starch to peptone significantly affected the functional genes and microbial community. This study demonstrates the dual synergism of microaeration to enhance the dissolution/hydrolysis/acidification of insoluble/macromolecular organics and sludge filterability for AnMBR application.

Cake Layer Fouling Potential Characterization for Wastewater Reverse Osmosis via Gradient Filtration

It is of great importance to quantitatively characterize feed fouling potential for the effective and efficient prevention and control of reverse osmosis membrane fouling. A gradient filtration method with microfiltration (MF 0.45 μm) → ultrafiltration (UF 100 kDa) → nanofiltration (NF 300 Da) was proposed to extract the cake layer fouling index, I, of different feed foulants in this study. MF, UF, and NF showed high rejection of model suspended solids (kaolin), colloids (sodium alginate and bovine serum albumin), and dissolved organic matters (humic acid) during constant-pressure individual filtration tests, where the cake layer was the dominant fouling mechanism, with I showing a good linear positive correlation with the foulant concentration. MF → UF → NF gradient filtration tests of synthetic wastewater (i.e., model mixture) showed that combined models were more effective than single models to analyze membrane fouling mechanisms. For each membrane of gradient filtration, I showed a positive correlation with the targeted foulant concentration. Therefore, a quantitative assessment method based on MF → UF → NF gradient filtration, the correlation of combined fouling models, and the calculation of I would be useful for characterizing the fouling potentials of different foulants. This method was further successfully applied for characterizing the fouling potential of real wastewater (i.e., sludge supernatant from a membrane bioreactor treating dyeing and finishing wastewater).

Effect of Organic Substances on Nutrients Recovery by Struvite Electrochemical Precipitation from Synthetic Anaerobically Treated Swine Wastewater

Anaerobically treated swine wastewater contains large amounts of orthophosphate phosphorus, ammonium nitrogen and organic substances with potential nutrients recovery via struvite electrochemical precipitation post-treatment. Lab-scale batch experiments were systematically conducted in this study to investigate the effects of initial pH, current density, organic substances upon nutrients removal, and precipitates quality (characterized by X-ray diffraction, scanning electron microscopy and element analysis via acid dissolution method) during the struvite electrochemical precipitation process. The optimal conditions for the initial pH of 7.0 and current density of 4 mA/cm² favoured nutrients removal and precipitates quality (struvite purity of up to 94.2%) in the absence of organic substances. By contrast, a more adverse effect on nutrients removal, morphology and purity of precipitates was found by humic acid than by sodium alginate and bovine albumin in the individual presence of organic substances. Low concentration combination of bovine albumin, sodium alginate, and humic acid showed antagonistic inhibition effects, whereas a high concentration combination showed the accelerating inhibition effects. Initial pH adjustment from 7 to 8 could effectively mitigate the adverse effects on struvite electrochemical precipitation under high concentration combined with organic substances (500 mg/L bovine albumin, 500 mg/L sodium alginate, and 1500 mg/L humic acid); this may help improve struvite electrochemical precipitation technology in practical application for nutrients recovery from anaerobically treated swine wastewater.

Effects of taurine on growth performance, antioxidant capacity, and lipid metabolism in broiler chickens

To investigate the effects of dietary taurine supplementation on growth performance, antioxidant status, and lipid metabolism in broilers, 384 male broilers (Arbor Acres, 1 D of age) were randomly allocated into 4 groups with 8 replicates of 8 birds. Dietary treatments were supplemented with taurine at the level of 0.00, 2.50, 5.00, and 7.50 g/kg of the diet (denoted as CON, TAU1, TAU2, TAU3, respectively). The BW gain from 1 to 21 D and from 22 to 42 D were all increased linearly (linear, P < 0.001) by taurine supplementation. Throughout the trial period, the highest BW gain and favorable gain-to-feed ratio were observed in the TAU2 group. Taurine supplementation increased the antioxidant enzyme activities and decreased (linear, P < 0.001) the content of malondialdehyde in both serum and the liver of broilers and alleviated oxidative damage through enhancing (P < 0.05) the hepatic genes expression of nuclear factor erythroid-2-related factor 2 (NRF2), glutathione peroxidase (GPX), and heme oxygenase-1 (HO-1). Correspondingly, in serum, the activities of hepatic lipase and total lipase were decreased linearly and quadratically (linear and quadratic, P < 0.001) with the increasing inclusion of taurine in the diet. Meanwhile, in serum, the content of triglycerides was significantly decreased (P < 0.05), and except for TAU3, the total cholesterol content was also significantly decreased (P < 0.05) by taurine supplementation. In addition, the hepatic content of triglycerides was significantly decreased (P < 0.05) in the TAU1 and TAU2 groups. Compared with the CON group, the hepatic genes expression of adenosine monophosphate-activated protein kinase alpha (AMPKα), silent 1, (SIRT1) and carnitine palmitoyltransferase 1 (CPT-1) were all increased (P < 0.05), and sterol regulatory element-binding protein-1 (SREBP-1) expression was decreased (P < 0.05) in the TAU2 group. These results indicated that taurine supplementation improved the growth performance, antioxidant capacity, and lipid metabolism of broilers.

Removal and biotransformation pathway of antibiotic sulfamethoxazole from municipal wastewater treatment by anaerobic membrane bioreactor

A lab-scale mesophilic anaerobic membrane bioreactor (AnMBR) was used to treat synthetic municipal wastewater with variable concentrations of antibiotic Sulfamethoxazole (SMX) and bulk organics in this study. The removal and biotransformation pathway of SMX in the AnMBR were systematically investigated during a 170 d of operation under hydraulic retention time of 1 d. Average SMX removal was 97.1% under feed SMX of 10-1000 μg/L, decreasing to 91.6 and 88.0% under feed SMX of 10,000 and 100,000 μg/L due to the inhibition effects of high SMX loading rate on anaerobic microorganisms. SMX biotransformation followed pseudo-first order reaction kinetics based on SMX removal independent of feed SMX of 10-1000 μg/L during continuous operation and also in a batch test under initial SMX of 100,000 μg/L. According to the identified 7 transformation products (TPs) by gas chromatography-mass spectrometry, the biotransformation pathway of SMX from municipal wastewater treatment via AnMBR was first proposed to consist of 2 primary routes: 1) Butylbenzenesulfonamide without antibiotic toxicity dominated under feed SMX of 10-100 μg/L; 2) Sulfanilamide with much lower antibiotic toxicity than SMX dominated under feed SMX of 1000-100000 μg/L, further transforming to secondary TPs (4-Aminothiophenol, Aniline, Acetylsulfanilamide) and tertiary TPs (4-Acetylaminothiophenol, Acetylaniline).

Organic micropollutants removal in sequential batch reactor followed by nanofiltration from municipal wastewater treatment

The removal of 26 organic micropollutants (OMPs) in synthetic municipal wastewater was investigated via the process of aerobic sequential batch reactor (SBR) alone and SBR followed by nanofiltration (NF). SBR-NF performed better than SBR alone, ascribed to the contribution of NF: 1) complete biomass rejection resulted in diverse microbial community and much less fluctuated performance than SBR alone, and 2) direct OMPs rejection (74-98%) increased their retention time in SBR and thus overall removal via biodegradation/transformation and accumulation in SBR. Nine OMPs showed high biological removal (over 60%), 6 OMPs showed moderate biological removal (30-70%) and 10 OMPs showed low biological removal (below 40%). Most readily and moderately biodegradable OMPs contained strong electron donating group. Most refractory OMPs contained strong electron withdrawing group and/or halogen substitute. The batch addition of powdered activated carbon (100 mg/L) into SBR showed short term sorption performance for both OMPs and bulk organics.

Polishing of anaerobic secondary effluent by Chlorella vulgaris under low light intensity

To investigate anaerobic secondary effluent polishing by microalgae (Chlorella vulgaris) under low light intensity (14μmol/m²/s), bubbling column reactors were operated in batches of 8 d with initial ammonium nitrogen 10-50mg/L, initial phosphate phosphorus 2-10mg/L and microalgal seed 40mg/L. Maximum microalgal biomass and minimum generation time were 370.9mg/L and 2.5d, respectively. Nitrogen removal (maximum 99.6%) was mainly attributed to microalgal growth rate, while phosphorus removal (maximum 49.8%) was related to microalgal growth rate, cell phosphorus content (maximum 1.5%) and initial nutrients ratio. Dissolved microalgal organics release in terms of chemical oxygen demand (maximum 63.2mg/L) and hexane extractable material (i.e., oil and grease, maximum 8.5mg/L) was firstly reported and mainly affected by nitrogen deficiency and deteriorated effluent quality. Ultrafiltration critical flux (16.6-39.5L/m²/h) showed negative linear correlation to microalgal biomass. Anaerobic membrane bioreactor effluent polishing showed similar results with slight inhibition to synthetic effluent.

Non-destructive shadowgraph imaging of ultra-cold atoms

An imaging system is presented that is capable of far-detuned non-destructive imaging of a Bose-Einstein condensate with the signal proportional to the second spatial derivative of the density. Whilst demonstrated with application to Rb85, the technique generalizes to other atomic species and is shown to be capable of a signal-to-noise of ∼25 at 1 GHz detuning with 100 in-trap images showing no observable heating or atom loss. The technique is also applied to the observation of individual trajectories of stochastic dynamics inaccessible to single shot imaging. Coupled with a fast optical phase locked loop, the system is capable of dynamically switching to resonant absorption imaging during the experiment.

Organic micropollutants in aerobic and anaerobic membrane bioreactors: Changes in microbial communities and gene expression

Organic micro-pollutants (OMPs) are contaminants of emerging concern in wastewater treatment due to the risk of their proliferation into the environment, but their impact on the biological treatment process is not well understood. The purpose of this study is to examine the effects of the presence of OMPs on the core microbial populations of wastewater treatment. Two nanofiltration-coupled membrane bioreactors (aerobic and anaerobic) were subjected to the same operating conditions while treating synthetic municipal wastewater spiked with OMPs. Microbial community dynamics, gene expression levels, and antibiotic resistance genes were analyzed using molecular-based approaches. Results showed that presence of OMPs in the wastewater feed had a clear effect on keystone bacterial populations in both the aerobic and anaerobic sludge while also significantly impacting biodegradation-associated gene expression levels. Finally, multiple antibiotic-type OMPs were found to have higher removal rates in the anaerobic MBR, while associated antibiotic resistance genes were lower.

In-situ atomic layer deposition of tri-methylaluminum and water on pristine single-crystal (In)GaAs surfaces: electronic and electric structures

The electronic structure of single-crystal (In)GaAs deposited with tri-methylaluminum (TMA) and water via atomic layer deposition (ALD) is presented with high-resolution synchrotron radiation core-level photoemission and capacitance-voltage (CV) characteristics. The interaction of the precursor atoms with (In)GaAs is confined at the topmost surface layer. The Ga-vacant site on the GaAs(111)A-2 × 2 surface is filled with Al, thereby effectively passivating the As dangling bonds. The As-As dimers on the GaAs(001)-2 × 4 surface are entirely passivated by one cycle of TMA and water. The presumed layerwise deposition fails to happen in GaAs(001)-4 × 6. In In0.20Ga0.80As(001)-2 × 4, the edge row As atoms are partially bonded with the Al, and one released methyl then bonds with the In. It is suggested that the unpassivated surface and subsurface atoms cause large frequency dispersions in CV characteristics under the gate bias. We also found that the (In)GaAs surface is immune to water in ALD. However, the momentary exposure of it to air (less than one minute) introduces significant signals of native oxides. This indicates the necessity of in situ works of high κ/(In)GaAs-related experiments in order to know the precise interfacial atomic bonding and thus know the electronic characteristics. The electric CV measurements of the ALD-Al2O3 on these (In)GaAs surfaces are correlated with their electronic properties.

Excision of Mullerian duct remnant for persistent Mullerian duct syndrome provides favorable short- and mid-term outcomes

OBJECTIVE

In dealing with persistent Mullerian duct syndrome (PMDS), excision of Mullerian duct remnant (MDR) has been rarely mentioned in the past, but recent discussions have taken place. This study aimed to evaluate the operative feasibility and outcomes.

MATERIALS AND METHODS

Three patients with PMDS operated on with excision of MDR between 2000 and 2009 were enrolled. Medical records were retrospectively collected and reviewed.

RESULTS

Bilateral undescended testis was manifested in all cases. Two patients presented with incarcerated hernia, requiring emergency herniorrhaphy at the ages of 6 months and 10 days, respectively. Reconstruction comprising simultaneous MDR excision and orchiopexy was made at the age of 1 year. MDR was incidentally found in another patient during operation for undescended testis. Immediate reconstruction was accomplished. Follow-up periods were 12.0, 3.5, and 2.5 years, respectively. Worse outcomes were noted on the two testes with repeated operations for incarcerated hernias, whereas the outcomes on the other four testes with a single operation were favorable.

CONCLUSIONS

Excision of MDR is technically feasible, and provides favorable outcomes in cases of a single operation. For experienced surgeons, immediate reconstruction should be the priority when this abnormality is incidentally encountered at an age suitable for orchiopexy.

Sustainable organic loading rate and energy recovery potential of mesophilic anaerobic membrane bioreactor for municipal wastewater treatment

The overall performance of a mesophilic anaerobic membrane bioreactor (AnMBR) for synthetic municipal wastewater treatment was investigated under a range of organic loading rate (OLR). A very steady and high chemical oxygen demand (COD) removal (around 98%) was achieved over a broad range of volumetric OLR of 0.8-10 gCOD/L/d. The sustainable volumetric and sludge OLR satisfying a permeate COD below 50 mg/L for general reuse was 6 gCOD/L/d and 0.63 gCOD/gMLVSS (mixed liquor volatile suspended solids)/d, respectively. At a high sludge OLR of over 0.6 gCOD/gMLVSS/d, the AnMBR achieved high methane production of over 300 ml/gCOD (even approaching the theoretical value of 382 ml/gCOD). A low biomass production of 0.015-0.026 gMLVSS/gCOD and a sustainable flux of 6L/m(2)/h were observed. The integration of a heat pump and forward osmosis into the mesophilic AnMBR process would be a promising way for net energy recovery from typical municipal wastewater in a temperate area.

Optimal Design for Marker-assisted Gene Pyramiding in Cross Population

Marker-assisted gene pyramiding aims to produce individuals with superior economic traits according to the optimal breeding scheme which involves selecting a series of favorite target alleles after cross of base populations and pyramiding them into a single genotype. Inspired by the science of evolutionary computation, we used the metaphor of hill-climbing to model the dynamic behavior of gene pyramiding. In consideration of the traditional cross program of animals along with the features of animal segregating populations, four types of cross programs and two types of selection strategies for gene pyramiding are performed from a practical perspective. Two population cross for pyramiding two genes (denoted II), three population cascading cross for pyramiding three genes(denoted III), four population symmetry (denoted IIII-S) and cascading cross for pyramiding four genes (denoted IIII-C), and various schemes (denoted cross program-A–E) are designed for each cross program given different levels of initial favorite allele frequencies, base population sizes and trait heritabilities. The process of gene pyramiding breeding for various schemes are simulated and compared based on the population hamming distance, average superior genotype frequencies and average phenotypic values. By simulation, the results show that the larger base population size and the higher the initial favorite allele frequency the higher the efficiency of gene pyramiding. Parents cross order is shown to be the most important factor in a cascading cross, but has no significant influence on the symmetric cross. The results also show that genotypic selection strategy is superior to phenotypic selection in accelerating gene pyramiding. Moreover, the method and corresponding software was used to compare different cross schemes and selection strategies.

Critical flux and chemical cleaning-in-place during the long-term operation of a pilot-scale submerged membrane bioreactor for municipal wastewater treatment

The critical flux and chemical cleaning-in-place (CIP) in a long-term operation of a pilot-scale submerged membrane bioreactor for municipal wastewater treatment were investigated. Steady filtration under high flux (30 L/(m(2) h)) was successfully achieved due to effective membrane fouling control by sub-critical flux operation and chemical CIP with sodium hypochlorite (NaClO) in both trans-membrane pressure (TMP) controlling mode (cleaning with high concentration NaClO of 2000-3000 mg/L in terms of effective chorine was performed when TMP rose to 15 kPa) and time controlling mode (cleanings were performed weekly and monthly respectively with low concentration NaClO (500-1000 mg/L) and high concentration NaClO (3000 mg/L)). Microscopic analysis on membrane fibers before and after high concentration NaClO was also conducted. Images of scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed that NaClO CIP could effectively remove gel layer, the dominant fouling under sub-critical flux operation. Porosity measurements indicated that NaClO CIP could partially remove pore blockage fouling. The analyses from fourier transform infrared spectrometry (FTIR) with attenuated total reflectance accessory (ATR) and energy dispersive spectrometer (EDS) demonstrated that protein-like macromolecular organics and inorganics were the important components of the fouling layer. The analysis of effluent quality before and after NaClO CIP showed no obvious effect on effluent quality.

Stable expression of rice dwarf virus Pns10 suppresses the post-transcriptional gene silencing in transgenic Nicotiana benthamiana plants

RNA silencing is a conserved mechanism that defends against viral infection and retrotransposon activity for protection of the genome. Segment 10 (S10) of Rice dwarf virus (RDV) encodes Pns10 protein, a viral suppressor of RNAi that suppresses the host RNA silencing machinery. In this study, we obtained stable transgenic RDV-S10 Nicotiana benthamiana plants expressing Pns10. Suppression of post-transcriptional gene silencing (PTGS) by Pns10 supported the conclusion that this protein exhibited the RNA silencing suppressor activity. In particular, the transgenic plants stably expressing a viral suppressor of RNAi (VSR) provide a model system for investigating the mechanism of RNA silencing.

KEYWORDS

RNA silencing; VSR; Rice dwarf virus; Pns10; transgenic plant.

Absence of association between two insertion/deletion coding genetic polymorphisms of TIM-1 gene and asthma in Chinese Han population

TIM-1, a member of T-cell immunoglobulin domain and mucin domain (TIM) gene family, was implicated as an asthma susceptibility gene in previous studies. TIM-1 was expressed on CD4(+) T cells after activation and its expression was sustained preferentially in T-helper type 2 (T(H)2) but not in T(H)1 cells, therefore TIM-1 became a good candidate gene for atopic diseases. Recent studies indicated that two insertion/deletion (ins/del) coding genetic polymorphisms in exon 4 of TIM-1 were associated with asthma susceptibility in some but not in all populations. In order to investigate the relationship between TIM-1 genetic polymorphisms and asthma in Chinese Han population, we performed a case-control study for two insertion/deletion polymorphisms in TIM-1 exon 4 (5383_5397ins/del and 5509_5511delCAA) and a single nucleotide polymorphism (SNP) in intron 8 (IVS 8+9 G/A) between a healthy control group of 309 people and an asthma patient group of 352 people recruited from Chinese Han population. The polymorphisms were genotyped and the allele and genotype frequencies were analysed, but none of the three polymorphisms showed association with asthma susceptibility in single-locus association analyses. Linkage disequilibrium (LD) analyses demonstrated that the two insertion/deletion polymorphisms were in strong LD but the haplotypes constructed from these two polymorphisms showed no significant association with asthma. In conclusion, our findings suggest that 5383_5397ins/del, 5509_5511delCAA and SNP IVS 8+9 G/A polymorphisms are not associated with asthma susceptibility in Chinese Han population.

Lack of association between ADAM33 gene and asthma in a Chinese population

Asthma is a complex polygenic disease with gene-environment interactions being important. It has been previously suggested that ADAM33, which is a member of a gene family that encodes membrane-anchored proteins with a disintegrin and a metalloprotease domain, is primarily expressed in lung fibroblasts and bronchial smooth muscle cells and has been associated with airway remodelling and bronchial hyperresponsiveness. A significant association has previously been demonstrated between single nucleotide polymorphisms (SNPs) and haplotypes of the ADAM33 and asthma in ethnically diverse populations. To assess whether SNPs or haplotypes of ADAM33 are related to asthma in a Chinese Han population, we genotyped three SNPs of ADAM33 (7575G/A in intron 6, 11188A/T in intron 19, and 12433T/C in exon 20) in a case-control study involving 296 patients with asthma and 270 healthy controls. No significant association was detected between these three SNPs and asthma susceptibility in the Chinese population.

Effect of a suspended carrier on membrane fouling in a submerged membrane bioreactor

In an attempt at membrane fouling control, a kind of cylindrical plastic suspended carrier was added in a submerged membrane bioreactor (SMBR) and its effect was investigated in this study. According to the transmembrane pressure (TMP) profiles and the sludge characteristics in comparative runs with and without suspended carriers, it was found that the suspended carriers added in SMBR had two effects on membrane fouling: one was the positive effect of mechanically scouring the membrane surface and the other was the negative effect of breaking up sludge flocs. Sludge particle size distribution change was mainly responsible. It was suggested to apply the suspended carrier at higher MLSS concentration and lower carrier dose based on the consideration for retarding sludge breakage caused by the carrier. The experiment was conducted under higher MLSS (8 gL(-1)) and lower carrier dose (carrier volume/total volume = 10/). The TMP increase was effectively retarded by added suspended carriers compared to the system without addition of the carriers. The effect of suspended carriers on membrane fouling at high MLSS concentration was verified.

Characteristics of patients at a Taipei summer rock concert festival

BACKGROUND

Rock concerts are popular mass gatherings in Taiwan. Millions of fans participate in rock concerts in Taiwan each year. However, there were no reports on the characteristics of the patients seen in rock concerts in Taiwan.

METHODS

Medical care for a summer rock concert festival held in an outdoor stadium in Taipei was coordinated by emergency physicians of a medical center. About 50,000 attendees participated in the two-night concert. Three stations were set up to provide advanced medical care. A standardized form was used to collect information about patients.

RESULTS

A total of 28 cases visited the medical stations, fourteen cases each day. They were aged from 13 to 40 years, with an average of 20.8 +/- 6.4. Twenty-one cases were female and seven were male. Twenty-two (79%) were spectators, five (18%) were on-duty staff, and one was a by-stander. Based on an estimation of totally 50,000 participants in the stadium for this two-night festival, the medical use rate was roughly 5.6 PPTT (patients per ten thousand attendees). The most common major problem was fainting which accounted for 13 cases (46%). Of these 13 cases, three cases (23%) lost consciousness and 12 cases (92%) were female. Sixteen cases (57%) were classified as requiring ALS (advanced life support) and 12 cases (43%) as requiring BLS (basic life support). Most cases improved and were discharged after onsite treatment. Only one case was transferred by ambulance due to persistent chest pain. However, she recovered several hours later.

CONCLUSIONS

By this preliminary data, first reported in Taiwan, we found that the most common problem was fainting. More than half of the cases seen at the concert required advanced life support. A well-designed emergency medical service (EMS) system is mandatory to provide services for these events.

Different programs of activation-induced cell death are triggered in mature activated CTL by immunogenic and partially agonistic peptide ligands

Activation-induced cell death (AICD) of mature T cells plays an important role in the control of immune homeostasis and peripheral tolerance. TNFRs and Fas have been implicated in the induction of AICD. However, these molecules were shown to be dispensable, at least in some experimental systems, for downsizing of Ag-induced T cell expansions and development of tolerance in vivo. The conditions of T cell activation leading to T cell deletion in a death receptor-independent manner are not well characterized. Here we show that human CTLs die through a death receptor-independent apoptotic program upon triggering with a partially agonistic peptide ligand. This apoptotic process exhibits some features of T cell death due to lymphokine deprivation and is blocked by exogenous IL-2. Our data demonstrate that engagement of TCR by MHC-peptide complexes can trigger diverse apoptotic programs of AICD and that the choice between these programs is determined by the agonistic potency of MHC-peptide ligand.

A partially agonistic peptide acts as a selective inducer of apoptosis in CD8+ CTLs

We have analyzed the effect of partially agonistic peptides on the activation and survival of CTL clones specific for a highly immunogenic HLA A11-restricted peptide epitope derived from the EBV nuclear Ag-4. Several analogues with substitutions of TCR contact residues were able to trigger cytotoxic activity without induction of IL-2 mRNA and protein or T cell proliferation. Triggering with these partial agonists in the absence of exogenous IL-2 resulted in down-regulation of the cytotoxic potential of the specific CTLs. One analogue selectively triggered apoptosis as efficiently as the original epitope, subdividing the partial agonists into apoptosis-inducing and noninducing ligands. Analysis of early T cell activation events, induction of Ca2+ influx, and acid release did not reveal significant differences between the two types of analogue peptides. These results demonstrate that some partial agonists can dissociate the induction of CTL death from CTL activation. Peptides with such properties may serve as useful tools to study signal transduction pathways in CD8+ lymphocytes and as therapeutic agents modulating natural immune responses.

The effect of subcutaneous r-HuEPO in cancer patients receiving chemotherapy with anemia: a preliminary report

BACKGROUND

Chemotherapy-related anemia in cancer patients is often encountered in clinical practice. It can reduce patient's compliance and tolerance to continuing chemotherapy. The mechanism of anemia may be ascribed to either decreasing serum EPO concentration or reducing sensitivity of EPO. Exogenous supply of EPO has shown to be effective in control of cancer-related anemia in early reports. This study preliminarily explored the efficacy and safety of r-HuEPO for cancer patients with anemia during the cytotoxic chemotherapy period in Taiwan.

METHODS

Sixteen cancer patients receiving cyclic chemotherapy with anemia (Hgb < or = 10.5 g/dl) and without other systemic organ dysfunction, cerebral metastasis, uncontrolled hypertension, or presence of anemia attributable to causes other than cancer and chemotherapy entered the study. All patients received r-HuEPO 150 u/kg subcutaneous injection tiw for a total of 16 weeks. The efficacy determinations was based on the effect of r-HuEPO on hematological parameters, transfusion requirements, quality of life assessment, and physician's global assessment. Safety was assessed based on clinical laboratory tests, vital sign measurements and the incidence and severity of adverse experiences.

RESULTS

There were no changes of WBC and platelet count in 4, 8, 12 and 16 weeks of r-HuEPO therapy. The mean hemoglobin values at baseline, week 4, 8, 12, and 16 were 9.2 +/- 1.0 g/dl, 11.4 +/- 0.9 g/dl, 11.6 +/- 1.8 g/dl, 11.8 +/- 1.8 g/dl, and 12.2 +/- 2.3 g/dl, respectively (p < 0.001). The mean hematocrit values at baseline, week 4, 8, 12, and 16 were 28.3 +/- 3.4%, 36.0 +/- 2.8%, 36.3 +/- 5.7%, 37.8 +/- 6.0%, and 40.1 +/- 7.1%, respectively (p < 0.0005). The use of r-HuEPO had the marginal effect on the increase of patient's energy and activity. No adverse impacts on patient's vital signs were noted except 2 incidences of systolic hypertension and one episode of diastolic hypertension in the week 4.

CONCLUSIONS

Subcutaneous injection of r-HuEPO at the dose of 150 u/kg tiw was safe and effective in increasing patient's hematocrit and RBC mass, and decreasing their blood transfusion requirement. Whether the current dosage of 150 u/kg tiw is the optimal treatment for chemotherapy-related anemia still needs further study.

Effectiveness of a continuous quality improvement program aiming to reduce unplanned extubation: a prospective study

OBJECTIVE

To evaluate the effectiveness of a continuous quality improvement (CQI) program in reducing the incidence of unplanned endotracheal extubation.

DESIGN

Prospective study over a 9-month period.

SETTING

Adult intensive care units (ICUs including coronary care unit, medical ICU, surgical ICU, and cardiovascular surgical ICU) in a university-affiliated medical center.

PATIENTS

831 consecutive mechanically ventilated patients.

INTERVENTIONS

CQI program focusing on standardization of procedures, improvement of communication, and identification and management of high-risk patients.

MEASUREMENTS AND RESULTS

With the implementation of this CQI program, the overall incidence density of unplanned extubation (defined as number of new unplanned extubations per mechanical ventilation patient-days) significantly decreased from 2.6% in the first trimester to 1.5% in the second trimester and 1.2% in the third trimester (p = 0.01). This reduction was essentially the result of a decrease in unplanned extubation in orally intubated patients (incidence density 4.6, 1.7 and 1.0% for three trimesters, respectively; p < 0.0001). Unplanned extubation in nasally intubated patients remained largely unaffected (1.2, 1.4, and 1.4% for three trimesters, respectively; p = 0.92).

CONCLUSIONS

The implementation of a concerted CQI program is effective in reducing the overall incidence of unplanned endotracheal extubation.

Selective IgA deficiency and anaphylactoid transfusion reaction: a case report

Anaphylactoid transfusion reaction following the administration of incompatible blood products can be life threatening, but accounts for only a very small proportion of all transfusion reactions. One of the causes of anaphylactoid transfusion reaction is the reaction of patient's anti-immunoglobulin A(IgA) with plasma IgA which is usually present in transfused blood. We report a case who had anaphylactoid transfusion reactions after transfusion of only a few milliliters of packed RBC from 3 consecutive donors, in spite of compatible pretransfusion crossmatches. The patient's serum revealed IgA deficiency accompanied by high-titer anti-IgA. The family study showed that one of her sons had partial IgA deficiency accompanied by anti-IgA2. In conclusion, although selective IgA deficiency is rare in Taiwan, it may still occasionally result in severe anaphylactoid transfusion reactions.

Trisomy 21 in acute myeloid leukemia

We report two cases of acute myeloid leukemia (AML), constitutionally normal, with trisomy 21. Trisomy 21 does not often occur as a sole numerical karyotypic abnormality in AML leukemia. The possible prognostic significance of the finding in acute leukemia is discussed.

Adjuvant methotrexate, vinblastine and cisplatin chemotherapy for invasive transitional cell carcinoma: Taiwan experience

PURPOSE

The feasibility of adjuvant cisplatin, methotrexate and vinblastine chemotherapy was evaluated in Taiwanese patients with invasive transitional cell carcinoma at high risk for recurrence.

MATERIALS AND METHODS

We assigned 56 patients with high risk transitional cell carcinoma (vascular or lymphatic invasion in the primary tumor, poorly differentiated stage P2, P3, P4 or N+ and M0) to receive adjuvant chemotherapy after radical urological surgery. The chemotherapy consisted of 40 mg./m.2 methotrexate and 4 mg./m.2 vinblastine on days 1 and 8, and 100 mg./m.2 cisplatin on day 2 given in 6 courses at 21-day intervals.

RESULTS

Median followup was 44 months. An average of 4.63 cycles of chemotherapy was administered. The median actual survival was 44 months, and the 1 and 3-year survival probabilities were 92% and 50%, respectively. The median disease-free survival was 15.5 months, and the 1 and 3-year disease-free survival probabilities were 66% and 28%, respectively. Only 5 (9%) and 1 (2%) patients had grades 3 and 4 leukopenia, respectively, and none died of sepsis.

CONCLUSIONS

The use of adjuvant cisplatin, methotrexate and vinblastine chemotherapy in patients with invasive transitional cell carcinoma at high risk for recurrence is feasible with tolerable toxicity but randomized controlled trials will be required to assess the benefit.

Treatment of advanced gastric cancer with a modified regimen of etoposide/leucovorin/5-fluorouracil

The efficacy and toxicity of a combination of etoposide 100 mg/m2/day iv on day 2-4, leucovorin 300 mg/m2/day iv, and 5-FU 500 mg/m2 day iv on day 1-5 every 4 weeks were assessed in 21 patients with advanced gastric cancer with measurable or evaluable diseases. Eight patients had an objective response, including 3 in CR. The overall response rate was 38.1% (95% CI 33.4-42.8%). Five of 8 patients who exhibited locally advanced and unresectable diseases had an objective response (2 CR, 3 PR). The response rate in patients with metastatic disease was 23.0% (95% CI 14.4-31.6%). The median progression-free interval and overall survival time were 7 and 10 months, respectively. The most frequent side effect was alopecia (Gr I/II 71.4%). No treatment-related death occurred. Modified ELF is a relatively effective and tolerable combination regimen for advanced gastric cancer and can be safely administered to elderly patients and patients with systemic diseases.

Allogeneic peripheral blood progenitor cell transplant after bone marrow graft failure: report of a case

A 31-year-old woman diagnosed with acute myelocytic leukemia received an allogeneic peripheral blood progenitor cell (PBPC) transplant one month after a previous bone marrow graft failed. PBPCs were mobilized with granulocyte-colony-stimulating factor and collected by apheresis. T-cell depletion was not performed and no further chemo- or radiotherapy was given for the second transplant. Engraftment was prompt, with the peripheral blood leukocyte count rising dramatically to 2,400/microL, six days after completion of PBPC transplant. The platelet count reached 36,000/microL on the eighth day and was self-sustained thereafter. Both blood grouping and bone marrow karyotyping confirmed donor origin of the engraftment. At the time of writing, the patient has been disease-free for over 200 days without any complications of acute or chronic graft-versus-host disease.

Comparison of intravenous granisetron with metoclopramide in the treatment of chemotherapy-induced emesis

BACKGROUND

It is well known that chemotherapy-induced nausea and vomiting not only produce undesirable physical effects but also reduce patients' willingness to continue chemotherapy. The effect of a 5HT3 receptor antagonist, granisetron, on antiemesis was studied in patients who were receiving cisplatin-based chemotherapy.

METHODS

Forty patients with malignant diseases, who were scheduled to receive cisplatin-based chemotherapy, were randomly assigned to receive either a single intravenous dose of granisetron (3 mg) (n = 20) or multiple doses of metoclopramide (2 mg/kg) (n = 20) as trial. The efficacy of antiemetic therapy was assessed based on the patient's subjective assessment of nausea and vomiting, and the physician's global evaluation of nausea and vomiting in the first 24 hours and during the following 6 days.

RESULTS

During the first 24 hours, there was a statistically significant advantage for the granisetron group in terms of prevention of both nausea and vomiting. The number of complete responders in the first 24 hours for the granisetron and metoclopramide groups was 16 (80%) and 9 (45%), respectively (p < 0.05). The control rate of anti-nausea over 6 days was 45% and 5% in the granisetron and metoclopramide groups, respectively (p < 0.001). The frequency of adverse events in the granisetron and metoclopramide groups was 10% and 45%, respectively. Analysis of laboratory data showed no significant difference between these two groups prior to and after administration of chemotherapy.

CONCLUSIONS

A single 5-minute infusion of 3 mg granisetron was more effective and produced a less adverse effect than multiple doses of metoclopramide in controlling chemotherapy-induced emesis, both in the first 24 hours and over a 6-day period.

Identification of Asp258 as the metal coordinate of pigeon liver malic enzyme by site-specific mutagenesis

Pigeon liver malic enzyme was inactivated by ferrous sulfate in the presence of ascorbate. Manganese and some other divalent metal ions provided complete protection of the enzyme against the Fe(2+)-induced inactivation. The inactivated enzyme was subsequently cleaved by the Fe(2+)-ascorbate system at Asp258-Ile259, which was presumably the Mn(2+)-binding site of the enzyme [Wei, C. H., Chou, W. Y., Huang, S. M., Lin, C. C., & Chang, G. G. (1994) Biochemistry 33, 7793-7936]. For identification of Asp258 as the putative metal-binding site of the enzyme, we prepared four mutant enzymes substituted at Asp258 with glutamate (D258E), asparagine (D258N), lysine (D258K), or alanine (D258A), respectively. These mutant proteins were recombinantly expressed in a bacterial expression system (pET-15b) with a stretch of histidine residues attached at the N-terminus and were successfully purified to apparent homogeneity by a single Ni-chelated affinity column. Among the four mutants, only D258E possessed 0.8% residual activity after purification; all other purified mutants had < 0.0001% residual activity in catalyzing the oxidative decarboxylation of L-malate. The D258E mutant was susceptible to inactivation by the Fe(2+)-ascorbate system, albeit with much slower inactivation rate, and was protected by the Mn2+ to a lesser extent as compared to the wild-type enzyme. None of the mutants were cleaved by the Fe(2+)-ascorbate system under conditions that cleaved the natural or wild-type enzyme at Asp258.(ABSTRACT TRUNCATED AT 250 WORDS)

Liver disease after bone marrow transplantation--the Taiwan experience

To investigate the causes of impaired liver function (LF)* after BMT, 88 patients were included for analysis of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, transplant methods, preconditioning regimens, and graft-versus-host disease (GVHD). Fifty of them (56.8%) developed abnormal LF after BMT and among them, 29 (32.9%) developed chronic hepatitis (CH). By univariate analysis, HCV infection, pretransplant abnormal LF, allogeneic BMT, and preconditioning regimen with total body irradiation were all significantly related to higher incidence of post-BMT impaired LF. However, only HCV infection, pretransplant abnormal LF, and acute GVHD were associated with higher incidence of CH. By multivariate logistic regression analysis, HCV infection and pretransplant abnormal LF were the two most significant interpreters for abnormal LF, especially for CH (odds ratios: 7.86 and 4.735, respectively) after BMT. Although the incidence of abnormal LF was found high in this study, there was no significant disadvantage in terms of survival for patients who developed abnormal acute and chronic liver function after BMT. However, a long-term follow-up is needed to evaluate survival pathology of CH, such as liver cirrhosis and hepatoma.

Cytogenetic studies in de novo acute nonlymphocytic leukemia

BACKGROUND

There is currently considerable interest in the cytogenetic analysis of leukemia. The improvement of banding techniques has made it possible to rather precisely identify deletion, translocation, inversions, and other structural chromosome abnormalities. Specific recurring chromosome abnormalities associated with distinctive morphologic features are thus increasingly recognized in acute nonlymphocytic leukemia. For example, uneven geographic distribution of nonrandom specific chromosome aberrations has been reported. We herein report the results of chromosome studies on 30 Chinese patients with de novo acute nonlymphocytic leukemia.

METHODS

Cytogenetic studies were performed at Veterans General Hospital-Taipei, from 1988 to 1993, on unselected samples of 30 patients with de novo acute nonlymphocytic leukemia. Chromosome analysis was performed by short-term culture techniques on bone marrow material obtained from patients at diagnosis. Metaphase chromosomes were banded by the conventional trypsin-Giemsa banding technique and then karyotyped according to the International System for Human Cytogenetic Nomenclature (ISCN). Classification of leukemia was based on the criteria of the French-American-British cooperative group.

RESULTS

Of the 30 patients with adequate specimens, 17 (56%) demonstrated clonal chromosome abnormalities. Six patients were found to have structural rearrangements and seven patients have a numerical change as the sole abnormality. Four patients showed both structural and numerical anomalies. t(8;21) was found in 1 of the 8 M2 type ANLL patients and two of them had monosomy 21. Four of the 6 patients with acute promyelocytic leukemia (APL; M3 subtype) showed t(15;17). Two patients with M4 type leukemia and abnormal bone marrow eosinophils showed inv(16)(p13q22). One patient with M4 type leukemia demonstrated the loss of chromosome #7 and none showed the loss or deletion of chromosome #5.

CONCLUSIONS

This study revealed a consistent finding of t(15;17) in APL; however, a low incidence of t(8;21), -5/5q- and -7/7q- in our patients demonstrated the possible difference in the incidence of chromosomal abnormalities in ANLL between the oriental peoples and the whites.

Induction of proteinuria by adriamycin or bovine serum albumin in the mouse

To establish models of proteinuria in the mouse, BALB/c mice were injected with puromycin aminonucleoside (PAN, 1.5 or 4.5 mg/10 g body weight), adriamycin (AD, 0.2 mg/10 g body weight) intravenously or bovine serum albumin (BSA, 100 mg/10 g body weight) intraperitoneally. Proteinuria was measured as the ratio of urinary albumin (micrograms/ml) to creatinine (mg/dl) and further characterized by isotyping the immunoglobulin. Although not obtained with PAN (followed for 4 weeks), proteinuria was readily attained in the mouse after treatment with AD or BSA. Most AD-treated mice (5/7) developed an abrupt increase of proteinuria at day 2 after injection, with the ratio of urinary albumin to creatinine in the range 0.28-0.45. The degree of proteinuria increased with time and all mice tested (7/7) showed overt proteinuria at day 4. These mice became anuric at day 5 and died at days 6 and 7. For BSA, 4 h after administration, four of seven mice showed enhanced proteinuria, lasting 8 h with urinary albumin and creatinine in a ratio < 0.05. Isotyping of urine samples collected at the time of heavy proteinuria (ratio of urinary albumin to creatinine: > 0.40 for AD-treated mice, > 0.15 for BSA-treated mice) showed that all of the mice (7/7) with AD-induced proteinuria (ADp) and three of four mice with BSA-induced proteinuria (BSAp) revealed urinary IgG2b and IgA, while only one of seven control mice showed IgG2b alone in urine. The mice were sacrificed at the time they presented with heavy proteinura for pathologic and anionic studies on renal tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

Affinity cleavage at the putative metal-binding site of pigeon liver malic enzyme by the Fe(2+)-ascorbate system

Pigeon liver malic enzyme was rapidly inactivated by micromolar concentrations of ferrous sulfate in the presence of ascorbate at neutral pH and 0 or 25 degrees C. Omitting the ascorbate or replacing the ferrous ion with manganese ion did not lead to any inactivation. Manganese, magnesium, zinc, cobalt, or calcium ion at 200 molar excess over ferrous ion offered complete protection of the enzyme from Fe(2+)-induced inactivation. Ni2+ provided partial protection, while Ba2+ or imidazole was ineffective in protection. Addition of 4 mM Mn2+ or 5 mM EDTA into a partially modified enzyme stopped further inactivation of the enzyme. Inclusion of substrates (L-malate or NADP+, singly or in combination) in the incubation mixture did not affect the inactivation rate. The enzyme inactivation was demonstrated to be followed by protein cleavage. Native pigeon liver malic enzyme had a subunit M(r) of 65,000. The inactivated enzyme with residual activity of only 0.3% was cleaved into two fragments with M(r) of 31,000 and 34,000, respectively. The cleavage site was identified as the peptide bond between Asp258 and Ile259. Native pigeon liver malic enzyme was blocked at the N-terminus. Cleavage at the putative metal-binding site exposed a new N-terminus, which was identified to be at the 34-kDa fragment containing the C-terminal half of original sequence 259-557. Our results indicated that Fe2+ catalyzed a specific oxidation of pigeon liver malic enzyme at Asp258 and/or some other essential amino acid residues that caused enzyme inactivation. The modified enzyme was then affinity cleaved at the Mn(2+)-binding site.

Bone marrow transplantation in Taiwan: low incidence of acute GVHD in patients with hematologic malignancies and severe aplastic anemia

A total of 116 consecutive patients, including 82 cases of hematologic malignancies and 34 cases of severe aplastic anemia (SAA), were treated by allogeneic bone marrow transplantation (BMT). The conditioning regimens and post-graft immunosuppressive agents were as described by Thomas in Seattle and Santos in Baltimore. The incidence of grades II-IV acute GVHD in patients with hematologic malignancies with a full HLA match, with one locus and with two loci mismatches was 6.3% (4 of 63), 0% (0 of 11) and 37.5% (3 of 8), respectively. None of SAA patients developed grade II-IV acute GVHD. The low incidence of acute GVHD after BMT among Chinese patients may be associated with the use of isolation in laminar airflow rooms and a relatively low level of genetic diversity in histocompatibility antigens. This is an interesting issue for further study.

Epithelioid leiomyosarcoma of the breast: report of a case

A 36-year-old female presented with a palpable mass in the right breast. She received a modified radical mastectomy after admission. Brain and multiple bony metastases were noted 10 months later. Microscopically, the tumor was composed of nodules of small spindle and large round cells showing abundant eosinophilic, vacuolated cytoplasm and prominent nucleoli. No glandular or ductular differentiation could be identified. By immunohistochemistry, the tumor cells were positive for vimentin and desmin in focal areas, but negative for cytokeratin, S-100, epithelial membrane antigen, actin, myoglobin, or alpha-1-antichymotrypsin. Electron microscopy showed focally cohesive large cells maintained together by poorly-defined intercellular junctions and surrounded segmentally by thin basal laminae. Intracytoplasmic filaments were identified in some tumor cells, diffusely arranged in the cytoplasm. These findings indicate that this was a case of epithelioid leiomyosarcoma of the breast. The literature concerning this rare neoplasm is reviewed.

Lupus nephritis, emphasizing tubulointerstitial lesions: a clinico-pathological analysis

Tubulointerstitial lesions (TIL) such as interstitial inflammation, fibrosis and tubular atrophy are frequently found in classes of lupus nephritis. A retrospective study evaluate lupus nephritis, the relationship between TIL and glomerular lesions, and the significance of TIL in assessing the severity and prognosis for cases of lupus nephritis. Between June 1983 and Jan 1990, 492 renal biopsies were performed. Lupus nephritis was diagnosed in 37 patients who fulfilled the American Rheumatology Association (ARA) criteria for Systemic lupus erythematosus (SLE). The results showed a significant correlation between degree of TIL and impairment of renal function. Degree of TIL and severity of glomerular lesions must be considered simultaneously to predict renal function of patients with lupus nephritis.

Intracerebral malignant fibrous histiocytoma: case report and review of the literature

A 50-year-old woman developed an intracerebral malignant fibrous histiocytoma at the site of a previously clipped aneurysm in the right temporal lobe. This tumor rarely originates within the brain. Review of the literature suggests that postoperative and/or postirradiation effects may contribute to the growth of this particular tumor.

Reactive sites of an anticarcinogenic Bowman-Birk proteinase inhibitor are similar to other trypsin inhibitors

The three-dimensional structure of the Bowman-Birk type proteinase inhibitor (PI-II) has been determined by x-ray crystallography and refined at 2.5-A resolution. This protein is a specific inhibitor of trypsin. Two reactive site loops, one at each end of the PI-II molecule, are structurally similar to each other and to reactive-site loops of pancreatic secretory trypsin inhibitor (Bolognesi, M., Gatti, G., Menegatti, E., Guarneri, M., Marquart, M., Papamokos, E., and Huber, R. (1982) J. Mol. Biol. 162, 839-869) and bovine pancreatic trypsin inhibitor (Deisenhofer, J., and Steigemann, W. (1975) Acta Crystallogr. B31, 238-250). PI-II is the first reported Bowman-Birk type inhibitor structure to be refined at high resolution, providing further insight into inhibitor mechanisms.

Focal glomerulosclerosis: a clinico-pathological analysis of 36 adult patients with idiopathic nephrotic syndrome

A retrospective study was conducted to determine the clinicopathological correlation of focal glomerulosclerosis in 36 adult patients with idiopathic nephrotic syndrome. All cases were divided into two groups, focal segmental glomerulosclerosis (FSGS, 23 cases) and focal global glomerulosclerosis (FGBG, 13 cases), on the basis of pathological findings. Most patients with FSGS were non-responsive/partial-responsive (22/22) to the corticosteroid treatment. By contrast, those with FGBG gave a relatively high responsive rate of 7/12 to the same therapy. The 5 non-responders with FGBG, however, were noted to have intensive interstitial fibrosis/mononuclear cell infiltrate of the renal lesions (4 cases), or diffusely glomerular Clq deposition without other coexisting immune deposits (1 case). Most cases of FSGS (20/23) became steroid dependent or remained heavy proteinuria resistant to corticosteroids/other immunosuppressive agents over a mean of 3.4 (ranged, 1 to 7) years after renal biopsy. Three of the 5 patients of FGBG initially non-responsive/partial-responsive to corticosteroids turned out to have protein-free urine (less than 4 mg/hr/m2) (2 patients) 1 month after leaving the hospital and became mildly proteinuric (1 patient) two months after discharge, respectively. The remainders of FGBG (10/13) were free of protein in their urine sample or had occasional episodes of proteinuria over a mean duration of 4.1 (ranged, 1 to 7) years. In addition, chronic renal insufficiency on discharge was noted in 2 cases of FSGS (2/23) and 1 case of FGBG (1/13). Only two cases of FSGS (2/23) progressed into a uremic status 3 and 5 years, respectively, after the time of the presumed clinical onset of their disease. These findings suggest that FGBG clinically behaves similar to a minimal change disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Simultaneous renal cell carcinoma and angiomyolipoma in a kidney--a case report and literature review

Renal cell carcinoma (RCC) is the most common tumor of the kidney. Angiomyolipoma is frequently present in the patient who has the stigma of tuberous sclerosis. We reported a case of a 39-year-old female, without the stigma of tuberous sclerosis, who was admitted on account of a firm, huge, fixed and palpable mass over the left flank region for one week. After radical nephrectomy, the pathological report was renal cell carcinoma, granular cell type, associated with angiomyolipoma. The literature concerning this unusual case is reviewed.

A new crystal form of ricin-OR

Ricin-OR, an antitumor toxin, has been crystallized in space group P2 with cell parameters a = 8.77 nm, b = 4.64 nm, c = 7.64 nm and beta = 101 degrees. There is one molecule in the asymmetric unit and the solvent content is estimated to be 48% by volume. The crystals diffract to 0.25 nm resolution which is higher than that of the previously reported C2 crystal form which had a solvent content of 65%.

Crystallization of two cubic forms of soybean trypsin inhibitor E-I, a member of the Bowman-Birk inhibitor family

The soybean trypsin inhibitor E-I, known to be relatively rich in methionine and cysteine, has been crystallized at room temperature in the presence of polyethylene glycol 4000, sodium chloride, and ammonium sulfate. A pronounced polymorphism in the crystals has been observed and two distinctly different cubic forms have been identified. Of the two, one form crystallizes in a unit cell of symmetry F432 with parameters a = b = c = 128.0 A, and diffracts at least to 2.6-A resolution. Each of the 96 asymmetric units contains one protein molecule, and has a solvent content of 60% by volume. The other form is of space group P4132 or P4332 with the unit-cell edge 87.1 A, and diffracts barely to 3-A spacings. The unit cell is composed of 24 asymmetric units, each of which probably also contains one molecule and has a solvent content of 69% by volume. The former cubic form appears to be more suitable for x-ray study than the latter in terms of stability and the extent of diffraction.

Preliminary crystallographic data for Bowman-Birk inhibitor from soybean seeds

A well characterized soybean protease inhibitor, the Bowman-Birk inhibitor, has been crystallized at room temperature in the presence of polyethylene glycol 4000 by vapor diffusion against an ammonium sulfate solution containing 2-methyl-2,4-pentanediol. An x-ray diffraction study reveals that the inhibitor crystallizes in a hexagonal unit cell of symmetry P6122 (or P6522) and dimensions a = b = 91.36(2) A and c = 63.92(2) A. Each of the 12 asymmetric units contains 2 molecules of molecular weight 8000. The crystal, which diffracts barely to 3-A spacings, is fairly stable to x-irradiation and has a solvent content of approximately 52% by volume.