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Recent developments in the instrumentation and data analysis of synchrotron small‐angle X‐ray scattering (SAXS) on biomolecules in solution have made biological SAXS (BioSAXS) a mature and popular tool in structural biology. This article reports on an advanced endstation developed at beamline 13A of the 3.0 GeV Taiwan Photon Source for biological small‐ and wide‐angle X‐ray scattering (SAXS–WAXS or SWAXS). The endstation features an in‐vacuum SWAXS detection system comprising two mobile area detectors (Eiger X 9M/1M) and an online size‐exclusion chromatography system incorporating several optical probes including a UV–Vis absorption spectrometer and refractometer. The instrumentation and automation allow simultaneous SAXS–WAXS data collection and data reduction for high‐throughput biomolecular conformation and composition determinations. The performance of the endstation is illustrated with the SWAXS data collected for several model proteins in solution, covering a scattering vector magnitude q across three orders of magnitude. The crystal‐model fittings to the data in the q range ∼0.005–2.0 Å−1 indicate high similarity of the solution structures of the proteins to their crystalline forms, except for some subtle hydration‐dependent local details. These results open up new horizons of SWAXS in studying correlated local and global structures of biomolecules in solution. [ABSTRACT FROM AUTHOR]

The optical design and performance of the recently opened 13A biological small‐angle X‐ray scattering (SAXS) beamline at the 3.0 GeV Taiwan Photon Source of the National Synchrotron Radiation Research Center are reported. The beamline is designed for studies of biological structures and kinetics in a wide range of length and time scales, from angstrom to micrometre and from microsecond to minutes. A 4 m IU24 undulator of the beamline provides high‐flux X‐rays in the energy range 4.0–23.0 keV. MoB4C double‐multilayer and Si(111) double‐crystal monochromators (DMM/DCM) are combined on the same rotating platform for a smooth rotation transition from a high‐flux beam of ∼4 × 1014 photons s−1 to a high‐energy‐resolution beam of ΔE/E ≃ 1.5 × 10−4; both modes share a constant beam exit. With a set of Kirkpatrick–Baez (KB) mirrors, the X‐ray beam is focused to the farthest SAXS detector position, 52 m from the source. A downstream four‐bounce crystal collimator, comprising two sets of Si(311) double crystals arranged in a dispersive configuration, optionally collimate the DCM (vertically diffracted) beam in the horizontal direction for ultra‐SAXS with a minimum scattering vector q down to 0.0004 Å−1, which allows resolving ordered d‐spacing up to 1 µm. A microbeam, of 10–50 µm beam size, is tailored by a combined set of high‐heat‐load slits followed by micrometre‐precision slits situated at the front‐end 15.5 m position. The second set of KB mirrors then focus the beam to the 40 m sample position, with a demagnification ratio of ∼1.5. A detecting system comprising two in‐vacuum X‐ray pixel detectors is installed to perform synchronized small‐ and wide‐angle X‐ray scattering data collections. The observed beamline performance proves the feasibility of having compound features of high flux, microbeam and ultra‐SAXS in one beamline. [ABSTRACT FROM AUTHOR]

Charge trapping (CT) and fixed charge (FC) are considered in the model of transient negative capacitance (TNC). The roles of CT and FC on subthreshold characteristics of ferroelectric FET (FeFET) are investigated by experiment and simulation. The simulation results show that both CT and FC can modulate the subthreshold characteristics of FeFET by shifting the operation point dynamically and statically, respectively. In addition, ferroelectric hysteresis can be reduced by the compensation due to CT and minor loop formation due to FC in a certain Vg sweep range. As a result, sub-60 mV/decade subthreshold swing (SS) with nearly hysteresis-free operation observed in experiments can be qualitatively reproduced by our simulation framework of TNC if both CT and FC are well-considered. [ABSTRACT FROM AUTHOR]

Due to the axisymmetrical parts easy to occur fracture or wrinkle in stamping process, by using the professional press finite element software and the control variable method the simple finite element simulation analysis on the barrel member is performed. In order to explore the effect of blank holder force, coefficient of friction and other factors on the barrel shape of flow parts in the stamping process and the influence on the forming quality of stamping parts are determined. [ABSTRACT FROM AUTHOR]

This study evaluated the impact of urbanization over northern Taiwan using the Weather Research and Forecasting (WRF) model coupled with the Noah land-surface model and a modified Urban Canopy Model (WRF-UCM2D). In the original UCM coupled in WRF (WRF-UCM), when the land use in the model grid net is identified as "urban", the urban fraction value is fixed. Similarly, the UCM assumes the distribution of anthropogenic heat (AH) to be constant. Such not only may lead to over- or underestimation, the temperature difference between urban and non-urban areas has also been neglected. To overcome the above-mentioned limitations and to improve the performance of the original UCM model, WRF-UCM is modified to consider the 2-D urban fraction and AH (WRF-UCM2D). The two models were found to have comparable simulation performance for urban areas but large differences in simulated results were observed for non-urban, especially at nighttime. WRF-UCM2D yielded a higher R² than WRF-UCM (0.72 vs. 0.48, respectively), while bias and RMSE achieved by WRF-UCM2D were both significantly smaller than those attained by WRF-UCM (0.27 and 1.27 vs. 1.12 and 1.89, respectively). In other words, the improved model not only enhanced correlation but also reduced bias and RMSE for the nighttime data of non-urban areas. WRF-UCM2D performed much better than WRF-UCM at non-urban stations with low urban fraction during nighttime. The improved simulation performance of WRF-UCM2D at non-urban area is attributed to the energy exchange which enables efficient turbulence mixing at low urban fraction. The achievement of this study has a crucial implication for assessing the impacts of urbanization on air quality and regional climate. [ABSTRACT FROM AUTHOR]

To compensate for the poor quality of thick-plate blanking parts in cross-section, this paper suggests using the optimizing bilateral ring gear holder parameters to increase burnish zone and improve cutting precision. With the bilateral gear ring, the hydrostatic pressure of shear deformation zone will increase, plasticity of the material will be lifted to maximum and quality of the cross section will be raised. This paper establishes 8mm AISI-1020 fine blanking model by DEFORM2D, analysis different ring gear parameters and clearance that are influenced the stress-strain and cross section quality to predict forming defects. By using the bilateral gear ring blank holder, the poor quality of thick-plate blanking section is successfully enhanced. Therefore, the bilateral gear ring blank holder is vital to improve the quality of blanking parts and provide the reliable theory basis for the practical engineering application. [ABSTRACT FROM AUTHOR]

Drinking water shortage has become worse in recent decades. A new capacitive deionization (CDI) method for increasing water supplies through the effective desalination of seawater has been developed. Silver as nano Ag and Ag@C which was prepared by carbonization of the Ag+-β-cyclodextrin complex at 573 K for 30 min can add the antimicrobial function into the CDI process. The Ag@C and Ag nanoparticles dispersed on reduced graphene oxide (Ag@C/rGO and nano Ag/rGO) were used as the CDI electrodes. The nano Ag/rGO and Ag@C/rGO electrodes can reduce the charging resistant, and enhance the electrosorption capability. Better CDI efficiencies with the nano Ag/rGO and Ag@C/rGO electrodes can therefore be obtained. When reversed the voltage, the electrodes can be recovered up to 90% within 5 min. This work presents the feasibility for the nano Ag and Ag@C on rGO electrodes applied in CDI process to produce drinking water from seawater or saline water. [ABSTRACT FROM AUTHOR]

The latest H.264/AVC achieves better coding performance compared to prior video coding standards such as MPEG-2. To provide the interoperability between MPEG-2 and H.264/AVC, the authors propose an efficient inter/intra mode decision for MPEG-2 to H.264/AVC inter P-frame transcoding, which is completed in two stages. In the first stage, a zero-block inter/intra mode decision scheme is employed to select both candidate inter/intra modes for prediction based on MPEG-2 coded macroblock type and motion vector information. Fast motion estimation with various search windows is then incorporated into inter mode decision to improve computation to a great extent. For intra mode decision the authors suggest a sum of absolute transform differences based intra mode decision scheme to further eliminate improbable modes for rate-distortion optimisation calculations. The experimental results reveal that average 85% of computation time (a speed-up factor of seven) can be reduced compared to the fully decoding/encoding procedure. The degradation in the rate-distortion performance is fairly small. [ABSTRACT FROM AUTHOR]

After excluding 60 patients who recently had new drug intake, the authors unveiled a range of cutaneous manifestations including erythematous rash, widespread urticaria and chickenpox-like vesicles in 20.4% of all the remaining patients. Since COVID-19 negative patients, likely with other viral infections, may also have similar skin manifestation as COVID-19 positive patients do, the difference in the prevalence and morphology of skin rash between COVID-19 positive and negative patients warrants comparisons. As we have observed the heavy burden of triage and shortage of essential medical goods posed by the outspread of COVID-19, the introduction of an easy clinical assessment tool like classic COVID-19 skin manifestation is a novel path to cope with the challenge that we are facing during the pandemic. [Extracted from the article]

Although the high optical clarity exhibited by a high nitrile plastic is desirable for packaging of food and beverages, exposure of the high nitrile molded articles to water at elevated temperatures causes the plastic to become hazy and the optical clarity is substantially reduced. Containers used for food and beverage packaging are sometimes exposed to water at elevated temperatures. For example, the containers are washed with hot water preparatory to being filled with product and are also exposed to water at elevated temperatures if pasteurization or sterilization of the packaged product is required after the container is filled. [ABSTRACT FROM PUBLISHER]

In the commercial molding process, a plastic article is rapidly cooled in the mold from a temperature well above its Tg. As soon as the temperature decreases to the proximity of Tg, the mobility of a polymer molecule decreases rapidly, leading to the formation of excess free volume or excess enthalpy in the molded articles. [ABSTRACT FROM PUBLISHER]

The excellent barrier properties of high nitrile plastics offer potential as materials for use in packaging of carbonated beverages and oxygen-sensitive foodstuffs. However, due to the viscoelastic nature of thermoplastics, improvement in creep resistance is essential for pressurized containers, such as plastic beer and beverage bottles, to resist the dimensional increases with time. Biaxial orientation and annealing are both effective in reducing the creep rate of pressurized plastic beverage containers. [ABSTRACT FROM PUBLISHER]

In the present work an annealing technique for the reduction of free volume in the molded articles was demonstrated as an effective means for improving the creep resistance of high acrylonitrile polymers [1] as well as other amorphous polymers. [ABSTRACT FROM PUBLISHER]

Thin-film transistors with poly-Si nanowire (NW) channels enhanced by metal-induced lateral crystallization (MILC) are reported. The new device features a side-gate with self-aligned NW channels abutting the sidewalls of the gate structure. By adopting the MILC technique, the crystallinity of the NW channels is greatly enhanced, compared to those formed by solid-phase crystallization. As a result, the electrical performance of the devices could be significantly enhanced in terms of reduced subthreshold swing and threshold voltage as well as improved field-effect mobility. [ABSTRACT FROM AUTHOR]

A very simple and low-cost scheme is proposed for fabricating thin-film transistors with poly-Si nanowire (NW) channels. In this scheme, the poly-Si NW channel is formed by cleverly employing the poly-Si sidewall spacer technique. In addition, the poly-Si NW channel is genuinely exposed to the environment after the poly-Si sidewall spacer formation in the new scheme. This unique feature, together with its simplicity and low-cost, makes this approach very suitable for applications and manufacturing of bio-logic sensing devices. Good device performance is demonstrated in this letter. [ABSTRACT FROM AUTHOR]

We have grown spiral carbon nanofibers containing Pd metal clusters using the Pd2(dba)3 catalyzed decomposition of gaseous acetylene on molecular sieves (AlPO4-5) support. The microstructure and composition of the spiral carbon nanofibers were examined by the powder X-ray diffractometer and transmission electron microscope. The conductivity of the mat in the temperature range from 14 to 250 K could be described by the form of exp[-(T-1/4)]. The thermopower shows a remarkably linear behavior down to 40 K, reminiscent of some conducting polymers. The sign change of the thermopower suggests there exists more than one type of charge carrier, which could be ascribed to the different types of nanotube with various sizes of radius. The transport behavior of spiral carbon nanofibers containing Pd metal clusters will be discussed in the framework of the heterogeneous model. [Copyright &y& Elsevier]

Responses of the neurons in medulla oblongata and C8-T1 spinal cord lateral horn of rats induced by simulated weightlessness were investigated using anti-Fos protein and anti-tyrosine hydroxylase (TH) double staining immunohistochemical methods, and Nissl-staining technique respectively. After four weeks of tail-suspension, many Fos-like positive neurons were localized in the medullary visceral zone (MVZ), predominantly in the nucleus of tractus solitarii and ventrolateral medulla, and some of them showed TH-like immunoreactivity. Sizes of the cell bodies of the lateral horn neurons in C8-T1 segment were significantly increased in 4-wk tail-suspended rats (P<0.05) as compared with that in controls. The results suggest that the neurons in MVZ and the spinal lateral horn may be involved in the adaptation of central cardiovascular regulation during weightlessness.

Intracerebroventricular injection of senktide, a selective agonist for neurokinin B receptor (NK3), induced Fos expression in many neurons of the rat hypothalamus. Fos-positive neurons were predominantly present in the supraoptic and paraventricular hypothalamic nuclei, and some of them were seen in the lateral preoptic area, lateral hypothalamic area, arcuate nucleus, perifornical region, posterior hypothalamic area, circular nucleus, and along relatively large blood vessels (lateral hypothalamic perivascular nucleus) in the anterior hypothalamus. A double labeling study was performed to examine if vasopressin-containing neurons in the hypothalamus could be activated by the treatment. Neurons with both Fos-like immunoreactivity (-LI) and vasopressin-LI were found in the paraventricular nucleus, supraoptic nucleus, circular nucleus and lateral hypothalamic perivascular nucleus. In the supraoptic nucleus, about 87% of vasopressin-containing neurons exhibited Fos-LI, which corresponded to about 64% of Fos-positive neurons in the nucleus. In the paraventricular nucleus, about 80% of vasopressin-like immunoreactive neurons exhibited Fos-LI, which constituted about 51% of the total population of Fos-positive neurons in the region. The results suggest that NK3 receptor may be involved in the modulation of release of vasopressin from the hypothalamus in the rat.

Objective: To assess perceptual performances of patients with intracerebral hemorrhage (ICH) compared with those of ischemic patients early after stroke and to analyze the psychometric properties of three perceptual tests used in the study., Design: Cross-sectional study., Setting: A rehabilitation unit at a teaching hospital., Patients: Twenty-two stroke patients with ICH and 22 demographically matched stroke patients with infarction., Main Outcome Measures: Loewenstein Occupational Therapy Cognitive Assessment (LOTCA), Rivermead Perceptual Assessment Battery (RPAB), and Motor-Free Visual Perception Test (MVPT)., Results: Stroke patients with ICH had significantly more severe deficits on a task of thinking operations than did patients with infarction. A significant lateralized effect of stroke existed in the ICH group, with patients with right-hemisphere strokes scoring lower than patients with left-hemisphere strokes on the figure-ground discrimination subtest of the RPAB. A considerable overlap among the three instruments was found. Yet, the observed correlations between supposedly similar subtests from the tests proved to be moderate, indicating that to a certain extent these test measures tap different perceptual processes. Four factors were generated from a joint LOTCA-RPAB-MVPT factor analysis. They assessed different facets of perceptual functioning, including higher-level and lower-level perceptual skills, part/whole conceptual integration, and color perception. This factor pattern accounted for 75.5% of the variance., Conclusions: Higher-level perceptual functions tend to be relatively susceptible to ICH stroke pathology early in the course of the disease. This information has important clinical implications in the early treatment planning for the stroke patients with ICH, such that specific compensatory strategies for these deficiencies should be devised to facilitate a successful rehabilitation. Knowledge regarding the influences of specific deficits on the performance of daily activities may also be useful to the patients' family.

The potential dechlorination of hexachlorobenzene (HCB) in medium by 1,2,3-trichlorobenzene (TCB)-adapted mixed culture under three reducing conditions was investigated. It was found that strongest to weakest HCB dechlorination occurred in the order of methanogenic conditions > sulfate-reducing conditions > denitrifying conditions. Under denitrifying conditions, no dechlorination was observed during the first 20 days of incubation. Biotransformation occurred in this order: HCB-->pentachlorobenzene (PCB)-->1,2,3,5-tetrachlorobenzene (TeCB)-->1,3,5-TCB + 1,2,4-TCB-->1,3-dichlorobenzene (DCB), HCB dechlorination was delayed following treatment with ferric chloride and manganese dioxide, but enhanced by the addition of lactate and pyruvate under methanogenic or sulfate-reducing conditions, the addition of acetate had no significant effect on HCB dechlorination under any of the three reducing conditions. Sequential dechlorination was observed at concentrations of 2-50 mg/L, but at a significantly slower rate at the highest concentrations.

Background: Perilunate dislocation is an uncommon injury of the wrist due to hyperextension. The factors affecting its prognosis are still controversial. The aim of the present study was to review its fracture types, associated injuries, timing of surgery, different fixation methods and prognostic factors., Methods: Fourteen patients with perilunate dislocation or fracture dislocation were treated by open reduction and internal fixation, and were followed for at least 12 months. A functional scoring system and X-ray findings were used for follow-up evaluation., Results: Two patients had excellent results, six patients had good results, and four had fair results. Only two patients had poor results. Treatment delayed over one month, transscaphoid perilunar fracture dislocation, or fixation of the transscaphoid fracture with Kirschner wire was associated with poorer results., Conclusions: Early diagnosis of perilunate dislocation, prompt open reduction and rigid fixation for fracture combined with ligament repair can give more promising results.

The purpose of this study was to describe norms of pinch strength for normal Taiwanese adults and to investigate the effects of age, gender, height, weight, and digit length on pinch strength. Three types of pinch (i.e. tip, key, and palmar pinch) were measured for a sample of 356 adults aged 20 to 88 years from a major metropolitan city located in southern Taiwan. A newly calibrated B&L pinch gauge was used for strength measurements with a standardized position during testing. The dominant hand was tested first, followed by the nondominant hand. The average of two trials for each pinch strength test was used as the subject's test scores. The results indicated that in the male group, pinch strength remained relatively stable up to 50 to 59 years old before a decline began, whereas pinch strength peaked with the 40- to 59-year-old group for female subjects. Males were stronger than females on all prehension patterns. Pinch strength of the right hand was significantly affected by such variables as the lengths of thumb and index finger and height, along with weight. With regard to the left hand, only height and weight had significant impact on pinch strength. Finally, there was an overall 13% pinch strength difference between the dominant and nondominant hands for the total sample. These findings provide therapists with objective data concerning the pinch strength of the Taiwanese adult's hand for clinical use.

Arteriovenous fistulas affecting the mesenteric circulation are rare. To our knowledge, this is the first case report in which a large fistula was initially treated by steel coil embolization and, after failure of this procedure, subsequently surgically corrected. A case is reported and the literature reviewed.

Specific regions of the P1 adhesin structural gene of Mycoplasma pneumoniae hybridize to various parts of the mycoplasma genome, indicating their multiple-copy nature. In addition, restriction fragment length polymorphisms and sequence divergence have been observed in the P1 gene, permitting the classification of clinical isolates of M. pneumoniae into two groups, I and II. These data suggest that the observed P1 gene diversity may be explained by homologous recombination between similar but not identical multicopy P1-related sequences and the P1 structural gene. We used oligonucleotide probes specific to the diverged regions of the group I and group II P1 structural genes to clone and sequence multicopy P1-related DNA segments. We detected sequences in group I M. pneumoniae isolates that were homologous not only to the group I P1 structural gene but also to the diverged regions of the group II P1 structural gene. Likewise, sequences in group II clinical isolates that were homologous both to the group II P1 structural gene and the diverged regions of the group I P1 structural gene were detected.

The effects of high-energy shock waves (HESW) on a murine renal cell carcinoma (RenCa) was investigated. In vitro exposure of tumor cells to HESW resulted in a dose-dependent reduction in cell viability as determined by trypan blue dye exclusion, plating efficiency, growth curve, and soft agar clonogenic assays. Activity of lactic dehydrogenase (LDH) was detected in the supernatant after the HESW treatment due to cellular destruction, and a dose-dependent increase in cytocidal effect was demonstrated. Ultrastructural changes with swelling and distorted cristae of mitochondria, vacuolation, ribosomal lysis, and chromatinolysis were observed in HESW-treated RenCa cells. Flow cytometric (FCM) study revealed that DNA content of RenCa cells diminished after 200 HESW treatment, and RNA content of tumor cells decreased markedly after 400 HESW treatments. Partial or complete inhibition of tumor growth was shown in both animal modalities of subcutaneous inoculation and intravenous injection with sequential lung metastases. This study stressed again that HESW may play a role in combinational protocol for the treatment of human renal cell carcinoma in certain circumstances.

Clinical isolates of Mycoplasma pneumoniae previously shown to exhibit significant sequence divergency in a major 170 kDa adhesin, designated P1, were further characterized using restriction enzyme fingerprinting of genomic DNA and two-dimensional gel electrophoresis of total proteins. Numerous differences in DNA restriction patterns and protein profiles were found, possibly reflecting various degrees of virulence and antigenic potential.

In order to investigate the status of urinary kallikrein excretion (UKE) in various chronic renal diseases, we measured the UKE in 56 patients with chronic renal diseases. They ranged in age from 19 to 80 with 26 males and 30 females. Among them were 31 patients with primary glomerulonephritis (GN) without nephrotic syndrome, 8 with nephrotic syndrome, 10 with various renal diseases in the azotemic stage, 3 in the uremic stage and 4 with type I renal tubular acidosis (RTA) due to Sjögren syndrome. The primary GN patients who were on a low salt diet were classified as group II GN, while those who partook freely of salt were classified as group I GN. Thirty-six normal volunteers were enrolled as controls. Kallikrein activity was determined by enzymatic hydrolysis of synthetic chromogenic substrate S-2266. Urinary electrolytes were measured by flame photometry. The results showed that UKE was lower in patients with group I GN, azotemic or uremic patients and in patients with RTA, as compared with normal controls. If UKE was corrected by creatinine clearance (CCr), the UKE/CCr ratio was still lower in group I GN patients, but became higher in patients with azotemia and uremia. The UKE/CCr ratio was not different from that of controls or patients with RTA. In nephrotic patients, the UKE and UKE/CCr ratio were both higher than that for normal controls. However, in group II GN patients, neither UKE nor the UKE/CCr ratio differed from that of controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Previous studies have shown that hypomagnesuria induced by magnesium deficient diet causes calcium oxalate crystal deposition in renal tubules of hyperoxaluric rats and administration of magnesium to these rats results in prevention of calcium oxalate crystallization in their kidneys. Based on these studies magnesium was claimed to be beneficial for calcium oxalate stone patients. However, hypomagnesuria is not a common phenomenon. To better understand the role of magnesium as an inhibitor of calcium oxalate crystallization in urine, we studied the effect of magnesium on calcium oxalate urolithiasis in rats on a regular diet and a hyperoxaluric protocol. Excess magnesium was administered to male rats on regular diet and a lithogenic protocol. Magnesium administration to hyperoxaluric rats did not result in significant changes in urinary excretion of calcium or oxalate or in calcium oxalate relative supersaturation. Urinary excretion of citrate was also not significantly altered. Some animals from both groups, those on magnesium therapy and those not on magnesium therapy had crystals deposited in their renal tubules. We conclude that excess magnesium has no significant effect on calcium oxalate urolithiasis in normomagnesuric conditions.

We and others have used the term MVP dysautonomia for a particular subset of hyperadrenergic dysautonomia patients. The role of the stimulatory guanine nucleotide regulatory protein (Gs) in this dysautonomia was studied by cholate extraction of Gs from erythrocytes from 11 normal subjects and 14 symptomatic dysautonomic patients and reconstitution into cyc-S49 lymphoma membranes, which have normal receptor and adenylyl cyclase but lack Gs. Isoproterenol-stimulated adenylyl cyclase activity in the dysautonomia group was increased compared to that in controls [3.66 +/- 0.20 (mean +/- SE; n = 14) vs. 2.87 +/- 0.14 (n = 11) U cyc- reconstituted activity/mg erythrocyte protein; P less than 0.05]. beta-Adrenergic receptor high affinity state formation was greatest in the severely symptomatic group [KL/KH: severe symptoms, 130 +/- 48 (n = 6); mild symptoms, 33 +/- 7 (n = 7); control, 27 +/- 6 (n = 11); severe dysautonomia distinct, P less than 0.017]. Sodium dodecyl sulfate-polyacrylamide gels of cholera toxin-dependent ADP-ribosylated G-proteins yielded no gross distinction between severely symptomatic and control groups. This subset of hyperadrenergic dysautonomia patients, thus, has supercoupled beta 2-adrenergic receptors (increase in both agonist binding and cyclase activation) conferred by an abnormal Gs, whose effects on agonist binding reflect the severity of illness.

Hypertensive putaminal hemorrhage remains a major cause of hemorrhagic stroke carrying extremely high morbidity. Considerable controversy remains regarding the optimal form of therapy. Between 1983 and 1989 we conducted a prospective randomized trial with three treatment strategies: best medical management, best medical management plus intracranial pressure monitoring, and surgical evacuation. Only patients with significant deficit harboring a putaminal hematoma at least 3.0 cm in diameter were entered. The study was interrupted after 21 patients had been studied (9, best medical management; 4, intracranial pressure monitoring; and 8, surgical evacuation). No differences were found among groups for age, admission blood pressure, and time interval between onset of symptoms and arrival at hospital. None of the subjects were capable of returning to prestroke activity. Fifteen (71%) died or remained vegetative at 6 months, and only 4 (19%) were capable of independent life at home. Of the 9 patients in the best medical management arm, 7 were dead or vegetative. In the surgical group, 4 patients died and only 2 were capable of independent life. These results suggest that current medical and neurosurgical therapies remain ineffective in preventing the devastating neurologic consequences of hypertensive putaminal hemorrhage.

The genome size of Mycoplasma genitalium was determined by using restriction enzymes that infrequently cut its DNA. The calculated value of 577 to 590 kilobases is one-fourth smaller than the genome of Mycoplasma pneumoniae, which is considered among the smallest genomes of self-replicating organisms.

The Mycoplasma pneumoniae cytadhesin P1 genes from two groups of clinical isolates that display restriction fragment length polymorphisms were cloned and sequenced. Within each group the nucleotide sequences were identical, but two major differences were detected between the groups. These two stretches of sequence divergence were located in multiple-copy regions of the P1 gene and resulted in considerable amino acid changes.

Restriction enzyme fingerprinting of genomic DNA and Southern blots probed with subclones of the Mycoplasma pneumoniae cytadhesin P1 gene were used to characterize clinical isolates of M. pneumoniae. On the basis of the examination of 29 individual M. pneumoniae isolates, two distinct groups were established. Group 1, which displayed a 12-kilobase band following DNA digestion with HindIII, consisted of strain M129-B16 and three others obtained in the state of Washington during the 1960s. The remaining M. pneumoniae strains belonged to group 2, which lacked the 12-kilobase band and included samples from the 1940s, 1970s, and 1980s. This category also included the only M. pneumoniae strain isolated from the synovial fluid of an arthritic patient.

Genomic DNA obtained from Mycoplasma pneumoniae clinical isolates spanning a 30-year period was analyzed for the presence of polymorphism in their P1 cytadhesin genes. All clinical isolates expressed a 170-kilodalton P1 protein that reacted with anti-P1 monoclonal antibodies. However, Southern blot analysis of specific M. pneumoniae isolates with subclones of the P1 structural gene revealed the presence of restriction fragment length polymorphism, permitting the classification of their P1 genes into two distinct categories.

A lambda gt11 library of Mycoplasma genitalium genomic DNA was generated, and clones were identified using a pool of monoclonal antibodies directed against different epitopes of the 140 kDa adhesin protein. Because the 140 kDa protein of M. genitalium and the 170 kDa P1 adhesin of M. pneumoniae share biological properties such as a tip-associated location, cytadherence function and immunologic crossreactivity, we performed Southern blot analysis using these cloned partial 140 kDa gene fragments and 14 subclones that span the P1 structural gene of M. pneumoniae. Homologous regions of the two genes were identified.

Mycoplasma pneumoniae cytadhesin P1 was purified by monoclonal antibody affinity chromatography followed by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The N-terminal 18-amino-acid sequence of P1 was determined and used to design two synthetic oligonucleotides, a 14-mer corresponding to amino acids 1 to 5 and an 18-mer corresponding to amino acids 7 to 12. These oligonucleotides served as hybridization probes for the identification of the P1 gene by Southern blot analysis of M. pneumoniae DNA. The P1 gene was cloned into plasmid pUC19 and mapped by using appropriate restriction endonucleases. The DNA sequence of the entire P1 gene was determined by subcloning appropriate DNA fragments into bacteriophage M13 and sequencing the DNA by the dideoxy-chain-termination method. The P1 gene contains an open reading frame of 4,881 nucleotides coding for a protein of 1,627 amino acids with a calculated molecular weight of 176,288. Properties of the amino-terminal sequence suggest that protein P1 may be synthesized as a precursor with subsequent processing to a mature protein of a calculated molecular weight of 169,758. Potential antigenic sites were determined by hydrophilicity plots. A computer search revealed that part of the predicted P1 sequence is homologous to cytoskeletal keratin of mammalian species and human fibrinogen alpha chain precursor. These results demonstrate the uniqueness of P1 as a cytadhesin and virulence determinant.

The Mycoplasma pneumoniae cytadhesin P1 structural gene with flanking regions was labeled by nick translation and used as a probe to analyze gene copy number in M. pneumoniae. Multiple bands of genomic DNA were hybridized by the probe. To establish what part of the P1 gene existed as multiple copies, the P1 gene and regions adjacent to the 3' and 5' ends were divided with restriction enzymes into 14 segments ranging in size from 174 to 651 base pairs. These pieces were purified on agarose gels, subcloned into pUC19, purified, labeled by nick translation, and used to probe the entire M. pneumoniae genome. Several regions near the middle and carboxy end of the P1 structural gene hybridized to single copies. The remaining P1 subclones hybridized to multiple bands under stringent hybridization conditions, indicating extensive homology with other parts of the M. pneumoniae genome. The single- versus multiple-copy nature of P1 structural gene domains is discussed.

We have isolated cDNA clones encoding bovine pancreatic preproglucagon. Twenty-five putative preproglucagon clones were selected by screening 3,100 clones of a fetal bovine pancreas cDNA library with a synthetic oligodeoxynucleotide probe. The probe was a mixture of synthetic 17-base DNA oligomers constructed to correspond to the six carboxyl-terminal amino acids (residues 24-29) of mature glucagon. Restriction mapping of six of these clones suggested that they represented a single mRNA species. Primary sequence analysis of one clone containing a 1,200-base-pair DNA insert revealed that it contained an essentially full-length copy of glucagon mRNA. Analysis of the cDNA suggested a protein coding sequence of 540 nucleotides and 5'- and 3'-untranslated regions of 90 and 471 nucleotides, respectively. This cDNA sequence encoded a 20-amino acid signal sequence followed by one for glicentin, a 69-amino acid polypeptide containing an internal glucagon moiety that has been found in porcine intestines. Glicentin is followed by two additional glucagon-like peptides, each flanked by paired basic amino acids (Lys, Arg) characteristic of prohormone processing. These polypeptide sequences show striking homology with those for glucagon and other members of the glucagon family of peptides.

Unique cyclic compounds were found in the lipid fraction of Azotobacter vinelandii cysts. In addition to two major molecular species which had already been identified, 5-n-alkylresorcinol and its galactoside derivative, five other molecular species (two alkyl side chain homologs of each) were isolated, and their structures were established by infrared, ultraviolet, nuclear magnetic resonance, and mass spectroscopy. These 10 compounds were 6-n-heneicosylresorcylic acid methyl ester and 6-n-tricosylresorcylic acid methyl ester, 5-n-(2-hydroxy)heneicosylresorcinol and 5-n-(2-hydroxy-tricosylresorcinol, 5-n-heneicosyl-4-acetylresorcinol and 5-n-tricosyl-4-acetylresorcinol, 6-n-heneicosyl-4-hydroxypyran-2-one and 6-n-tricosyl-4-hydroxypyran-2-one, and 6-(2-oxotricosyl)-4-hydroxy-pyran-2-one and 6-(2-oxopentacosyl)-4-hydroxypyran-2-one.

The cytadhesin (P1) structural gene of a spontaneous mutant of Mycoplasma pneumoniae which displayed a P1-negative phenotype was analyzed. An extra adenine was discovered in a stretch of normally seven adenines near the N-terminal region of the mutant P1 structural gene. The frameshift mutation resulted in the early termination of protein translation. Possible causes of the mutation are discussed.

An animal experimental study was performed to investigate the prevention of scar formation after laminectomy by applying Gelfoam, a free-fat graft and steroids as interposing material between the dura and muscles. There were 52 adult guinea pigs equally divided into four groups. They were sacrificed 2 weeks, 4 weeks and 12 weeks respectively after surgery. In the control group, there was young fibrous tissue at 2 weeks, which became more mature at 4 weeks. At 12 weeks, it became mature with varying thickness and canal extension. In the steroid group, it showed the same picture as the control group. In the Gelfoam group, there was foreign body reaction with disintegration of Gelfoam at 2 to 4 weeks. At 12 weeks, however in the free-fat graft group, viable fat graft could be seen at the laminectomy site with little fibrous tissue overlying the dura. In the clinical part, from September 1981 to September 1984, one of the authors (PQC) performed 100 laminectomies on patients with various causes of low back pain. A piece of free subcutaneous fat was laid on dura before wound closure. At follow-up, there was no adverse effect pertaining to its application. Most patients had considerable pain relief after the surgery. From the above observation, we believe that a free-fat graft is a simple and effective way to prevent postlaminectomy membrane. Steroids and Gelfoam do not have such advantage.