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Ultrashort energetic terahertz (THz) pulses have created an exciting new area of research on light interactions with matter. For material studies in small laboratories, widely tunable femtosecond THz pulses with peak field strength close to MV cm-1 are desired. Currently, they can be largely acquired by optical rectification and difference frequency generation in crystals without inversion symmetry. We describe in this paper a novel scheme of THz pulse generation with no frequency tuning gap based on Raman-resonance-enhanced four-wave mixing in centrosymmetric media, particularly diamond. We show that we could generate highly stable, few-cycle pulses with near-Gaussian spatial and temporal profiles and carrier frequency tunable from 5 to >20 THz. They had a stable and controllable carrier-envelop phase and carried ~15 nJ energy per pulse at 10 THz (with a peak field strength of ~1 MV cm-1 at focus) from a 0.5-mm-thick diamond. The measured THz pulse characteristics agreed well with theoretical predictions. Other merits of the scheme are discussed, including the possibility of improving the THz output energy to a much higher level.

Abstract Obesity is considered a high-risk disease and a global epidemic, and the number of obese patients is rising at an alarming rate worldwide. High-fat diet-induced dysbiosis of the intestinal microbiota is considered an essential factor related to obesity. Bariatric surgery induces a sharp decrease in fat content and effectively improves the metabolism of obese individuals. Herein, we aimed to investigate the effects of a high-fat diet-induced obesity and the alterations in gastric and intestinal microbiota resulting from sleeve gastrectomy on clinical outcomes. We performed 16S sequencing of gastric and fecal samples obtained from rats in three treatment groups: normal chow diet, high-fat diet (HFD), and sleeve gastrectomy after HDF for 14 weeks. The area under the curve of fasting glucose and the levels of leptin and low-density lipoproteins were significantly different between groups. Microbial taxa that were highly correlated with several clinical parameters were identified for each group. Glyoxylate and dicarboxylate, taurine and hypotaurine, butanoate, nitrogen, and pyrimidine metabolism and aminoacyl-transfer ribonucleic acid biosynthesis were affected by bariatric surgery and were significantly associated with changes in the composition of gastric and fecal microbiomes. Connectivity and co-occurrence were higher in fecal samples than in gastric tissues. Our results elucidated the positive effects of sleeve gastrectomy in obesity and shed light on changes in the microbiomes of gastric and fecal samples.

ABSTRACTOral microbial ecosystem could influence intestinal diseases, but there have been insufficient studies demonstrating the association of microbial composition between the oral cavity and the intestinal system. Thus, we aimed to investigate the compositional network within the oral microbiome related to gut enterotype from saliva and stool samples collected from 112 healthy Korean subjects. Here, we performed bacterial 16S amplicon sequencing from clinical samples. Then, we determined oral microbiome type related to individual’s gut enterotype for healthy Korean. The co-occurrence analysis was performed to interactivity prediction of microbiome within saliva samples. As a result, it could be classified into two Korean oral microbiome types (KO) and four oral–gut-associated microbiome types (KOGA) according to distribution and significant differences of oral microflora. The co-occurrence analysis showed various bacterial compositional networks linked around Streptococcus and Haemophilus within healthy subjects. The present study was first approach in healthy Koreans to identify the oral microbiome types related to the gut microbiome and investigate their characteristics. Hence, we suggest that our results could be potential healthy control data for identifying differences in microbial composition between healthy people and oral disease patients and studying microbial association with the gut microbial environment (oral–gut microbiome axis).

PURPOSE To suggest future research directions and current research trends based on representative studies of existing exercises and the gut microbiome. In addition, we reviewed methodologies to study the relationship between exercise and the gut microbiome. METHODS The research methodologies and results were integrated through a literature review of the latest “exercise and gut microbiome” studies and a narrative review. RESULTS Although exercise is indirectly related to the gut microbiome or immunity, evidence for a direct effect is still lacking. However, with the recent discovery of gut microbiomes that can help improve exercise performance, it is clear that exercise can positively alter the gut microbiome. CONCLUSIONS Strong evidence suggests that regular moderate exercise improves overall immune function and lowers the incidence of inflammation-related disease. In addition, certain microorganisms affect exercise performance.

MicroRNA (miRNA) are found in numerous biofluids including blood and are considered a new class of biomarkers. The data presented here are related to the research article entitled “Profiling and identification of pregnancy-associated circulating microRNAs in dairy cattle” (Markkandan et al. 2018). In the cited article, we sequenced the circulating microRNAs of the three healthy dairy cows of normal and 30 days of pregnancy (DOP) using Illumina RNA-Seq. Differentially expressed genes (DEG) analysis between normal and pregnant samples showed perturbations in miRNA expression. Herein, we made a comparison of DEGs at normal and 60 DOP libraries. The analysis results showed that 147 known miRNAs were differently expressed at 60 DOP groups when compared to the normal group. In addition, stage specific miRNAs were also predicted. Keywords: Circulating microRNA, Holstein, MiRNA-sequencing, Exosome, Pregnancy

The human skin sebum suggests that it (along with other epidermal surface lipids) plays a role in skin barrier formation, the moderation of cutaneous inflammation, and antimicrobial defense. Various methods have been developed for collecting and measuring skin sebum. We tested methods of detection using “color intensity”, by staining the skin casual sebum. This process was conducted in three steps; first, the selection of materials for sebum collection; second, staining the collected sebum; third, the development of a device that can measure the level of stained sebum. A plastic film was used to effectively collect sebum that increased with the replacement time of the sebum. In addition, the collected sebum was stained with Oil Red O (ORO) and checked with RGB; as a result, the R2 value was higher than 0.9. It was also confirmed that the correlation value was higher than 0.9 in the comparison result with Sebumeter®, which is a common standard technology. Finally, it was confirmed that the R2 value was higher than 0.9 in the detection value using the sensor. In conclusion, we have proven the proof of concept (PoC) for this method, and we would like to introduce an effective sebum measurement method that differs from the existing method.

MicroRNAs (miRNAs) are known for their role in mRNA silencing via interference pathways. Repetitive elements (REs) share several characteristics with endogenous precursor miRNAs. In this study, 406 previously identified and 1,494 novel RE-derived miRNAs were sorted from the GENCODE v.19 database using the RepeatMasker program. They were divided into six major types, based on their genomic structure. More novel RE-derived miRNAs were confirmed than identified as RE-derived miRNAs. In conclusion, many miRNAs have not yet been identified, most of which are derived from REs.

Human endogenous retroviruses (HERV) sequences account for about 8% of the human genome. Through comparative genomics and literature mining, we identified a total of 29 human-specific HERV-K insertions. We characterized them focusing on their structure and flanking sequence. The results showed that four of the human-specific HERV-K insertions deleted human genomic sequences via non-classical insertion mechanisms. Interestingly, two of the human-specific HERV-K insertion loci contained two HERV-K internals and three LTR elements, a pattern which could be explained by LTR-LTR ectopic recombination or template switching. In addition, we conducted a polymorphic test and observed that twelve out of the 29 elements are polymorphic in the human population. In conclusion, human-specific HERV-K elements have inserted into human genome since the divergence of human and chimpanzee, causing human genomic changes. Thus, we believe that human-specific HERV-K activity has contributed to the genomic divergence between humans and chimpanzees, as well as within the human population.

Generation of octave-spanning spectrum that spans from 570 nm to 1300 nm utilizing 1030 nm 170 fs pulses from a Yb:KGW laser and a two-stage multiple-plate arrangement is demonstrated. 3.21 fs sub-single-cycle pulses are obtained after dispersion compensation. The high compression ratio of more than 50 times is achieved for two scenarios with widely different parameters including high input peak power at 1 kHz repetition rate and modest peak power at a high repetition rate of 100 kHz. The output pulses have good spatial mode quality and exhibit long-term stability. The achieved compression ratio and flexibility are unprecedented in ultrafast pulse compression to single-cycle regime. The experiments demonstrate that the technique of multiple-plate pulse compression is versatile and applicable for a wide range of laser pulse parameters.

The generation of high average power, carrier-envelope phase (CEP) stable, near-single-cycle pulses at a repetition rate of 100 kHz is demonstrated using an all solid-state setup. By exploiting self-phase modulation in thin quartz plates and air, the spectrum of intense pulses from a high-power, high repetition rate non-collinear optical parametric chirped pulse amplifier (NOPCPA) is extended to beyond one octave, and pulse compression down to 3.7 fs is achieved. The octave-spanning spectrum furthermore allows performing straightforward f-to-2f interferometry by frequency-doubling the long-wavelength part of the spectrum. Excellent CEP-stability is demonstrated for extended periods of time. A full spatio-spectral characterization of the compressed pulses shows only minor asymmetries between the two perpendicular beam axes. We believe that the completed system represents the first laser system satisfying all requirements for performing high repetition rate attosecond pump-probe experiments with fully correlated detection of all ions and electrons produced in the experiment.

We analyze femtosecond supercontinuum generation in a distribution of thin solid plates to show that the distributed scheme inhibits processes leading to pulse breakup while allowing spectral expansion to proceed as desired. We introduce basic criteria for setting the plate thickness or initial laser intensity and the location of each plate in the laser beam path and confirm that under these conditions a fully-coherent and intense supercontinuum can be generated for input peak power of as much as two thousand times the critical power for self-focusing of the solid medium.

An octave-spanning coherent supercontinuum is generated by non-collinear Raman-assisted four-wave mixing in single-crystal diamond using 7.7 fs laser pulses that have been chirped to about 420 fs in duration. The use of ultrabroad bandwidth pulses as input results in substantial overlap of the generated spectrum of the anti-Stokes sidebands, creating a phase-locked supercontinuum when all the sidebands are combined to overlap in time and space. The overall bandwidth of the generated supercontinuum is sufficient to support its compression to isolated few-to-single cycle attosecond transients. The significant spectral overlap of adjacent anti-Stokes sidebands allows the utilization of straight-forward spectral interferometry to test the relative phase coherence of the anti-Stokes outputs and is demonstrated here for two adjacent pairs of sidebands. The method can subsequently be employed to set the relative phase of the sidebands for pulse compression and for the synthesis of arbitrary field transients.

A broadband green light source was demonstrated using a tandem-poled lithium niobate (TPLN) crystal. The measured wavelength and temperature bandwidth were 6.5 nm and 100 °C, respectively, spectral bandwidth was 36 times broader than the periodically poled case. Although the conversion efficiency was smaller than in the periodic case, the TPLN device had a good figure of merit owing to the extremely large bandwidth for wavelength and temperature. The developed broadband green light source exhibited speckle noise approximately one-seventh of that in the conventional approach for a laser projection display.

We demonstrate the use of a nonlinear photonic crystal to generate a harmonic comb and an ultrabroad-band acousto-optic modulator for the field amplitudes and phases of the comb to succeed in synthesizing femtosecond and subfemtosecond optical field waveforms. Nonsinusoidal fields of various shapes are synthesized and verified using shaper-assisted linear cross-correlation. The compact all-solid-state system could lead to the realization of a portable arbitrary optical waveform synthesizer that is analogous in many aspects to an RF function generator.

Shaping the ferroelectric domains as waveguide, grating, lens, and prism are key to the successful penetration of periodically-poled ferroelectrics on various wavelength conversion applications. The complicated structures are, however, difficult to be fully characterized, especially the unexpected index contrast at the anti-parallel domain boundaries are typical in the order of 10(-4) or less. An ultrahigh resolution optical coherence tomography was employed to fully characterize the domain boundary and structure properties of a periodically-poled lithium niobate (PPLN) waveguide with an axial resolution of 0.68 μm, an transversal resolution of 3.2 μm, and an index contrast sensitivity of 4x10(-7). The anti-parallel domain uniformity can clearly be seen non-invasively. Dispersion of the ferroelectric material was also obtained from 500 to 750 nm., (© 2011 Optical Society of America)

Achieving the control of light fields in a manner similar in sophistication to the control of electromagnetic fields in the microwave and radiofrequency regimes has been a major challenge in optical physics research. We manipulated the phase and amplitude of five discrete harmonics spanning the blue to mid-infrared frequencies to produce instantaneous optical fields in the shape of square, sawtooth, and subcycle sine and cosine pulses at a repetition rate of 125 terahertz. Furthermore, we developed an all-optical shaper-assisted linear cross-correlation technique to retrieve these fields and thereby verified their shapes and confirmed the critical role of carrier-envelope phase in Fourier synthesis of optical waveforms.

We report a design for upconversion 435 nm blue lasers based on simultaneously fulfilling the nonlinear processes of optical parametric oscillation (OPO) and second-harmonic generation (SHG) in a 7.9 mum periodically poled lithium tantalate (PPLT). The uncoated 15-mm-long PPLT device exhibits a low threshold of 150 mW and a differential slope efficiency of 22.6%, rendering 56 mW blue generation when pumped by a pulsed 532 nm green laser with an average power rating of 400 mW. These observations were attributed to a quasi-phase-matching (QPM) structural design with a 75% domain duty cycle to ensure the concurrence of frequency doubling with the first-order QPM-OPO PPLT device via the second-order QPM-SHG process.

We report the generation of the second to the sixth harmonics of a fundamental frequency covering two and a half octaves in a multiply-periodically poled lithium tantalate crystal by cascaded quasi-phase-matched frequency mixing. A frequency comb that is composed of these harmonics will permit the synthesis of a train of periodic subcycle subfemtosecond pulses in a compact setting.

The process of generating periodic optical waveforms includes the generation and phasing of several harmonics of a fundamental frequency. In this work, we show that simultaneous generation and phasing of the harmonics can be performed in a monolithic aperiodic optical superlattice (AOS). Stable periodic waveforms can thus be delivered to a predetermined location by simply sending a laser beam through a properly designed and fabricated AOS crystal. A detailed mathematical description for generating the domain pattern in such an AOS crystal is given and the process is numerically demonstrated. The waveform that is generated from a monolithic AOS is highly reproducible and phase stable. We also use propagation in air as an example to show how any predictable phase and amplitude modifications such as air dispersion that will alter the desired waveform can be pre-compensated in the design phase of the AOS crystal.

We demonstrate control of the carrier-envelope phase of ultrashort periodic waveforms that are synthesized from a Raman-generated optical frequency comb. We generated the comb by adiabatically driving a molecular vibrational coherence with a beam at a fundamental frequency plus its second harmonic. Heterodyne measurements show that full interpulse phase locking of the comb components is realized. The results set the stage for the synthesis of periodic arbitrary waveforms in the femtosecond and subfemtosecond regimes with full control.

A compact tunable UV laser source based on intracavity sum frequency generation in a MgO-doped periodically-poled stoichiometric lithium tantalate optical parametric oscillator is reported. UV output at an approximately 1 mW level of power over the range of 364 to 378 nm with a bandwidth of 0.5 nm was obtained with a crystal that has just one periodically-poled grating period. The full tuning range can be as much as approximately 68 nm, from 324 to 392 nm by varying the crystal temperature from room temperature to 250 degrees C. This will cover nearly the entire UVA range.

We have analyzed optical parametric interaction in a 2D NPC. While in general the nonlinear coefficient is small compared to a 1D NPC, we show that at numerous orientations a multitude of reciprocal vectors contribute additively to enhance the gain in optical parametric amplification and oscillation in a 2D patterned crystal. In particular, we have derived the effective nonlinear coefficients for common-signal amplification and common-idler amplification for a tetragonal inverted domain pattern. We show that in the specific case of signal amplification with QPM by both G(10) and G(11), symmetry of the crystal results in coupled interaction with the corresponding signal amplification by G(10) and G(1,-1). As a consequence, this coupled utilization of all three reciprocal vectors leads to a substantial increase in parametric gain. Using PPLN we demonstrate numerically that a gain that comes close to that of a 1D QPM crystal could be realized in a 2D NPC with an inverted tetragonal domain pattern. This special mechanism produces two pairs of identical signal and idler beams propagating in mirror-imaged forward directions. In conjunction with this gain enhancement and multiple beams output we predict that there is a large pulling effect on the output wavelength due to dynamic signal build-up in the intrinsic noncollinear geometry of a 2D NPC OPO.

We describe the synthesis of periodic waveforms consisting of a train of pulses that are 0.83 cycles long and have an electric field pulse width of 0.44 fs using 7 Raman sidebands generated by molecular modulation in H2. We verify by optical correlation that the carrier-envelope phase is constant in these waveforms when they are synthesized from commensurate sidebands. The estimated overall shift of the carrier-envelope phase is less than 0.18 cycles from the first to the last pulse of nearly 10(6) pulses in the pulse train.

A model to analyze the interaction of the parametric fields being generated in a two-dimensional nonlinear photonic crystal has been developed. The analysis provides details of the interference of the generated wave(s) both inside and in the region just outside the crystal. The results are verified by second-harmonic generation in a LiNbO3 crystal that has been poled with a tetragonal inverted domain structure.

A high-power 532 nm-pumped multikilohertz nanosecond optical parametric oscillator using a periodically poled 1.0 mol.% MgO-doped stoichiometric lithium tantalate crystal that could be operated from room temperature to 200 degrees C without damage is reported. A broad continuous tuning range from 855 to 1410 nm was achieved within a single domain period. Efficient operation of high peak power and watt level average power with a power conversion of 62.5% was measured. These results show that a high-resolution high average power visible tunable source can be realized.

Detachment of heme prosthetic groups from gaseous myoglobin ions has been studied by collision-induced dissociation and infrared multiphoton dissociation in combination with Fourier-transform ion cyclotron resonance mass spectrometry. Multiply charged holomyoglobin ions (hMbn+) were generated by electrospray ionization and transferred to an ion cyclotron resonance cell, where the ions of interest were isolated and fragmented by either collision with Ar atoms or irradiation with 3 mum photons, producing apomyoglobin ions (aMbn+). Both charged heme loss (with [Fe(III)-heme]+ and aMb(n-1)+ as the products) and neutral heme loss (with [Fe(II)-heme] and aMbn+ as the products) were detected concurrently for hMbn+ produced from a myoglobin solution pretreated with reducing reagents. By reference to Ea = 0.9 eV determined by blackbody infrared radiative dissociation for charged heme loss of ferric hMbn+, an activation energy of 1.1 eV was deduced for neutral heme loss of ferrous hMbn+ with n = 9 and 10.

What we believe to be a novel multipass, acoustically open photoacoustic detector designed for fast-response, high-sensitivity detection of trace gases and pollutants in the atmosphere is demonstrated. The acoustic pulses generated by the absorption of the light pulses of a tunable optical parametric oscillator by target molecules are detected by an ultrasonic sensor at 40 kHz. The photoacoustic signal is enhanced by an optical multipass arrangement and by concentration of the acoustic energy to the surface of the ultrasonic sensor. The detection sensitivity, estimated from CO2 measurements around a 2 microm wavelength, is approximately 3.3 x 10(-9) W cm(-1).

We demonstrate a tunable deep-ultraviolet coherent source generated by the beating of a tunable UV laser and strongly driven vibrational Raman coherence in hydrogen. The total energy conversion efficiency reaches a maximum of 50% at the phase side of the Raman coherence. The generated spectrum of Raman sidebands tunes with the input and extends from 435 to 146 nm for an input at 282 nm.

A compact, efficient optical parametric oscillator (OPO) for the visible to near-infrared region based on periodically poled stoichiometric lithium tantalate pumped by a frequency-doubled multikilohertz Q-switched Nd:YAG laser is demonstrated. Up to 61% photon conversion with a 71% slope efficiency for photon conversion from 532 nm to the signal radiation was measured. We observed that the efficient conversion diminished the potential for photorefractive damage induced by the 532 nm radiation in the crystal and made sustained operation of the OPO device possible.

With a laser-excited acoustic wave as the carrier wave and by modulation of the light wavelength of a multikilohertz-repetition-rate optical parametric oscillator at a lower frequency than the acoustic frequency, we demonstrate a wavelength-amplitude double-modulation technique and achieve an enhancement factor of 35 in sensitivity in photoacoustic trace gas detection with the technique.

We have demonstrated a rovibrational-state-selected photoionization experiment using an IR laser and high-resolution VUV-synchrotron radiation. The VUV photoionization of acetylene [C2H2(Xtilde; (1)Sigma(+)(g);nu(3)=1,J(')=8 or 10)] prepared by IR excitation reveals three strong autoionizing Rydberg series converging to C2H+2(Xtilde; (2)Pi(u);nu(+)(3)=1) with little ion background interference. Rotational transitions resolved for the Rydberg states provide an estimate of approximately 1.8 ps for their lifetimes. This experiment opens the way for state-selective photoionization studies of polyatomic molecules using VUV-synchrotron radiation.

A pulsed periodically poled lithium niobate optical parametric oscillator operating in a cavity with a grazing-incidence grating configuration was used for sensitive and precise measurement of trace quantities of methane in nitrogen by photoacoustic spectroscopy with a novel differential photoacoustic detector. A sensitivity of 1.2 parts in 10(9) by volume of methane was obtained in direct calibration measurements (not extrapolated). With this apparatus, in situ measurement of the methane concentration in ambient air under atmospheric conditions was demonstrated.

Laser-induced excitation spectra of the two bands ã(3)B(1)-;X(1)A(1), 2(1)(0) and 1(1)(0) of (32)SO(2) and (34)SO(2) have been recorded in a supersonic jet at a resolution of 0.015 cm(-1). The rotational and electron-spin fine structure has been analyzed for both isotopic species. Analysis of the rotational and electron-spin fine structure yields precise values of the rotational constants A, B, and C and the spin constants alpha and beta for both (32)SO(2) and (34)SO(2) in the states ã(3)B(1) (010) and (100). No interaction between these two vibrational states with any nearby triplet state is observed for rotational levels with J

A human sequence IgGkappa anti-CD4 monoclonal antibody (mAb), HM6G, originally isolated from a human immunoglobulin transgenic mouse was specific for and bound with high binding avidity to the CD4 antigen expressed on human, chimpanzee, and cynomolgus monkey T cells. Prior to testing this mAb in human clinical trials, a number of preclinical primate studies were performed. In chimpanzees, HM6G did not deplete circulating CD4(+) T cells and was cleared in a dose-dependent manner. In contrast, this mAb administered to cynomolgus monkeys depleted CD4(+) T cells (albeit only at high doses) and its clearance, which had reached saturation even at very low doses, was much slower. These differences were most likely due to the additional and rather substantial expression of the CD4 antigen on chimpanzee monocytes. In monkeys, the T cell depletion was mitigated by infusing the mAb over 30 min or longer (as opposed to 30 s) while only slightly altering the clearance. As expected, the human mAb did not induce an immune response in chimpanzees, although it did induce a low titer response in monkeys. These disparate pharmacokinetic and pharmacodynamic results suggest prudence when extrapolating results obtained in nonhuman models to humans., (Copyright 1999 Academic Press.)

We constructed a cw Ti:Al(2)O(3) master oscillator-dye preamplifier-Ti:Al(2)O(3) power amplifier system that generates <2-ns, 100-mJ pulses. The system is tunable from 750 to 890 nm and has a repetition rate of 30 Hz. The output pulse has a near Fourier-transform-limited bandwidth of ~240 MHz. Backward stimulated Brillouin scattering is used to control the growth of amplified spontaneous emission (ASE). The content of ASE in the final output is under our detection limit (<10(-4)) for the entire tuning range.

Protegrin-1 (PG-1) is a cysteine-rich, 18-residue beta-sheet peptide isolated from porcine leukocytes with antimicrobial activity against a broad range of microorganisms. The MICs of PG-1 against representative gram-positive and gram-negative bacteria ranged from 0.12 to 2 microg/ml. At these levels, PG-1 was rapidly bactericidal in vitro, reducing the number of viable CFU of either methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa by more than three log units in less than 15 min. Resistance to PG-1 did not develop after 11 subculturings of P. aeruginosa or 18 subcultures of MRSA in Mueller-Hinton broth containing PG-1 at one-half the MIC. Under similar conditions of serial passage, the MICs of norfloxacin and gentamicin against P. aeruginosa increased 10 and 190 times, respectively. Similarly, the MIC of norfloxacin against MRSA increased 85 times. Immunocompetent mice inoculated intraperitoneally (i.p.) with P. aeruginosa or S. aureus exhibited 93 to 100% mortality in the vehicle control group compared with 0 to 27% mortality in animals that received a single i.p. injection of PG-1 (0.5 mg/kg of body weight). Mice inoculated with S. aureus by intravenous (i.v.) injection and dosed 0 to 60 min later with a single i.v. injection of PG-1 (5 mg/kg) had a mortality of 7 to 33%, compared to a mortality of 73 to 93% in the vehicle controls. In leukopenic mice inoculated i.v. with vancomycin-resistant Enterococcus faecium, mortality was 87% in the vehicle control group and 33% in animals that received a single i.v. injection of PG-1 (2.5 mg/kg). Taken together, these data indicate that PG-1 has potential for use as an antimicrobial agent in the treatment of local or systemic infections caused by clinically relevant pathogens.

A simple ring cavity consisting of mirrors reflecting at the second harmonic is used to generate the fourth harmonic of low-power Q-switched Nd:YAG laser pulses. A large beam waist of 1 mm minimized the effects of double refraction and thermal loading of the nonlinear crystals. By simulating the low-power pulses with a small portion of the output from a 30-Hz flash-lamp-pumped Q-switched Nd:YAG laser, we obtained IR-UV energy conversion as great as 39.5% to yield 84-mW average power at 266 nm from 213 mW of single-mode 1064-nm radiation.

Purpose: The pharmacokinetics of rBPI23, a recombinant amino terminal fragment of bactericidal/permeability-increasing protein that binds to and neutralizes endotoxin, was investigated., Methods: rBPI23 was administered to rats at doses 0.01-10 mg/kg and plasma rBPI23 levels were measured by ELISA. rBPI23 was also administered to bilaterally nephrectomized rats. In addition, rBPI23 was administered intra-hepatically via the pyloric vein to determine the first-pass effect by the liver. rBPI23 concentrations were also simultaneously measured in the right atrium and aorta to determine the removal of rBPI23 by the lungs., Results: The concentration-time profile of rBPI23 was described by a 3-compartmental model with parallel first order and Michaelis-Menten (saturable) elimination. The clearance of rBPI23 was not altered by bilateral nephrectomy. Clearance of intra-hepatically administered rBPI23 was 4.5 fold lower than intra-femorally administered rBPI23. The concentration difference of rBPI23 between aortic and right atrial blood was no greater than 11%. Clearance of rBPI23 in rats could be reduced up to 10 fold by co-administration of heparin. Uptake by liver of intra-hepatically administered rBPI23 was prevented by co-administration of heparin., Conclusions: rBPI23 is not significantly cleared by the kidneys, and no more than 11% of the rBPI23 was removed by the lungs with each pass. The liver could remove 78% of the rBPI23 from the hepatic circulation. Studies with heparin suggest rBPI23 is cleared by binding to heparan sulfate sites in the liver.

The pharmacokinetics of several proteins were investigated using two different assays. A 23 kDa recombinant protein fragment of bactericidal/permeability-increasing protein (rBPI23) was radiolabeled with 125I using Iodo-beads and administered rats. Plasma samples were collected and assayed for 125I-rBPI23 by radioactivity. In a separate experiment, rBPI23 was administered to rats and plasma samples were assayed for rBPI23 by ELISA. The clearance determined from plasma concentrations of 125I-rBPI23 measured by radioactivity was about 2.5-fold lower than that of rBPI23 determined by ELISA. In addition, the steady state volumes of distribution and mean residence times of 125I-rBPI23 measured by radioactivity were four-fold and 10-fold greater, respectively, compared to those measured by the ELISA method. By studying several proteins with a range of molecular weights, we found that the pharmacokinetics of proteins below about 60 kDa were different when assayed by radioactivity or ELISA, but those of proteins with molecular weights of at least 80 kDA revealed only minor differences. To determine which assay method yielded the correct plasma pharmacokinetic profile, rBPI23 was metabolically labeled with 35S-methionine and administered to rats, and plasma samples were assayed by radioactivity. The concentration-time profile assessed by this method was very close to that determined by ELISA. Exposing rBPI23 to chloramine-T (the oxidant used in the iodination process) and measuring its plasma concentration by ELISA revealed pharmacokinetics similar to those of the iodinated protein measured by radioactivity. In contrast, radiolabeling rBPI23 using iodinated Bolton-Hunter reagent (which avoids exposing the protein to oxidant), and measuring 125I-rBPI23 by radioactivity, yielded pharmacokinetics that were similar, although not identical, to the pharmacokinetics of rBPI23 measured by ELISA. Thus, our data suggest that directly iodinating low-molecular-weight proteins by oxidation procedures alters their clearance from the blood, preventing reliable determination of pharmacokinetic parameters.

Backward stimulated Brillouin scattering was used to control the growth of amplified spontaneous emission (ASE), reducing the unwanted emission in a pulse-amplified cw Ti:sapphire laser system from 22% to less than 1 x 10(-4) in the final output. Suppression of ASE substantially improved the spectral quality of the laser and broadened the range over which the laser is useful. The output duration was compressed, but the pulse remained nearly transform limited.

A phase I pharmacokinetic and safety clinical trial of rBPI23, a recombinant amino terminal fragment of bactericidal/permeability-increasing protein, was conducted in healthy male volunteers. rBPI23 was administered as a 5 or 30 min infusion at doses of .1 to 1 mg/kg. The pharmacokinetics of rBPI23 in human subjects were described by a bi-exponential disposition function with evidence of concentration-dependent kinetics. The alpha half-life increased significantly with increasing dose, from 4-5 min at .1 mg/kg to 7-8 min at 1 mg/kg. The beta half-life varied between 18 and 29 min regardless of dose and the clearance varied from 5 to 10 mL/min/kg. Very little, if any, of the administered rBPI23 was excreted intact in the urine. Electrocardiograms, ionized calcium concentration, prothrombin and partial prothrombin times, hematologic parameters, and blood chemistries remained normal. Furthermore, no antibody response to rBPI23 was observed in any of the subjects.

Fusion proteins between cell-targeting domains and cytotoxic proteins should be particularly effective therapeutic reagents. We constructed a family of immunofusion proteins linking humanized Fab, F(ab')2, or single chain antibody forms of the H65 antibody (which recognizes the CD5 antigen on the surface of human T cells) with the plant ribosome-inactivating protein gelonin. We reasoned that such an immunofusion would kill human target cells as efficiently as the previously described chemical conjugates of H65 and gelonin (Better M., Bernhard, S. L., Fishwild, D. M., Nolan, P. A., Bauer, R. J., Kung, A. H. C., and Carroll, S. F. (1994) J. Biol. Chem. 269, 9644-9650) if both the recognition and catalytic domains remained active, and a proper linkage between domains could be found. Immunofusion proteins were produced in Escherichia coli as secreted proteins and were recovered directly from the bacterial culture supernatant in an active form. All of the immunofusion proteins were purified by a common process and were tested for cytotoxicity toward antigen-positive human cells. A 20-60-fold range of cytotoxic activity was seen among the fusion family members, and several fusion proteins were identified which are approximately as active as effective chemical conjugates. Based on these constructs, immunofusion avidity and potency can be controlled by appropriate selection of antibody domains and ribosome-inactivating protein.

A series of acute and multiple dose toxicology studies were performed to support the clinical dose and to evaluate the systemic toxicity of an immunotoxin, H65-RTA. H65-RTA consists of a murine anti-CD5 monoclonal antibody and ricin A chain (RTA). The LD50 of H65-RTA was estimated to be between 60 and 62.5 mg/kg in the rat. H65-RTA was administered to the rat and the monkey as a bolus injection at doses of 0.1, 0.5, and 2 mg/kg and over 1-hr infusion at 0.2 and 2 mg/kg, respectively. Two to three weeks of postdosing recovery was included in the study design. Following repeated doses of H65-RTA, the following findings were demonstrated: peripheral edema, decreased body weight, decreased body temperature (monkey only) in addition to a general inflammatory reaction evidenced by changes in hematology, clinical chemistry, and urinalysis parameters. Histopathologically, chronic inflammation in the nonarticular soft tissue was found in the rat at doses of 0.1 mg/kg and higher and monkeys developed much more severe toxicity when compared to the rat at the same doses. Inflammation, hemorrhage, and/or edema were evident in a variety of tissues. Myeloid hyperplasia was also evident. Additional findings resulting from the drug-related stress involved adrenals, spleen, thymus, and lymph nodes. All toxicity was reversible. The antibody response was evident in rats at doses of 0.5 mg/kg and higher and in all monkeys at doses of 0.2 and 2 mg/kg. In conclusion, since H65 antibody does not cross-react with the T cells from either the rat or the cynomolgus monkey, the toxicity observed in the studies described above was not related to T lymphocytes and was probably due to a series of acute to subacute inflammatory reactions caused largely by the RTA moiety of H65-RTA.

Photon conversion efficiencies of 60% at 2.92 microm and 25% at 4.5 microm of a high-power injection-seeded Ti:sapphire laser have been achieved by difference frequency mixing with the new crystal KTiOAsO(4).

A recombinant 23-kDa amino-terminal fragment of human bactericidal/permeability-increasing protein (rBPI23), a potent lipopolysaccharide (LPS)-binding/neutralizing protein, was used as a probe to assess the role of endotoxin in the acute inflammatory responses elicited by gram-negative bacteria in rat subcutaneous air pouches. In initial experiments, rBPI23 prevented the Escherichia coli O111:B4 LPS-induced accumulation of polymorphonuclear leukocytes (PMN), tumor necrosis factor alpha (TNF-alpha), and nitrite (a stable end product of nitric oxide formation) in exudate fluids. Significant inhibition of TNF-alpha production was still evident when rBPI23 treatment was delayed for 30 min after LPS instillation. In subsequent experiments, rBPI23 also prevented the nitrite and early (2-h) TNF-alpha accumulation induced by three different strains of formaldehyde-killed gram-negative bacteria (E. coli O7:K1, E. coli O111:B4, and Pseudomonas aeruginosa 12.4.4) but did not inhibit the PMN or late (6-h) TNF-alpha accumulation induced by these bacteria. As with LPS challenge, a significant inhibition of early TNF-alpha production was still evident when rBPI23 treatment was delayed for 30 to 60 min after instillation of killed bacteria. The results indicate that in this experimental model the NO and early TNF-alpha responses to gram-negative bacterial challenge are mediated predominantly by endotoxin, whereas the PMN and late TNF-alpha responses may be mediated by other bacterial components. Moreover, the results indicate that rBPI23 can inhibit the bacterially induced production of certain potentially harmful mediators (TNF-alpha and NO) without entirely blocking the host defense, i.e., PMN response, against the bacteria.

Background and Objective: The CO2 laser is potentially useful for the surgical treatment of superficial bladder tumors. High water absorption of the CO2 laser beam and the lack of a flexible fiber delivery system has hindered development of cystoscopes designed to evaporate bladder tumors. This report describes a cystoscope capable of delivering a high-power CO2 laser beam to all parts of the urinary bladder., Study Design/materials and Methods: A rigid 24 Fr. cystoscope transmitting 80 Watts of power via an articulated arm and infrared waveguide was built. Beam manipulation is by reflection using a movable mirror. Smoke and urine are evacuated by continuous flow of CO2 purge gas. An isotopic laser delivering an 11.1 micron wavelength beam prevents resonant absorption. Conventional 30-70 degrees telescopes are used. Scope performance and lesion morphology were tested in four female pigs., Results: A total of 80-85% of the incident energy is delivered to the mucosa. All areas of the bladder mucosa can be evaporated. All components tolerate wetting. Mucosa and lamina propria are evaporated with 30 Joules of delivered energy. Perforation occurs after 120-160 Joules are delivered to a single spot., Conclusion: The limitations of power, beam transmission, beam manipulation within a small cavity, and resistance to wetting have been overcome.

Effects of an N-terminal fragment of bactericidal/permeability increasing protein (rBPI21) on bacterial infections were determined. Intravenous (i.v.) rBPI21 increased survival and reduced bacteremia in rats after an iv injection of Escherichia coli O7:K1 bacteria. rBPI21 inhibited the rise in tumor necrosis factor-alpha resulting from challenge with 2 strains of E. coli. Intraperitoneal (ip) injection of rBPI21 increased survival of mice after ip injection of E. coli O7:K1 and Pseudomonas aeruginosa and reduced bacteria in peritoneal lavage fluid and blood and inhibited cytokine production in response to E. coli. rBPI21 alone did not protect mice challenged with E. coli O111:B4 but was protective and reduced bacterial counts when administered in combination with the antibiotic cefamandole. The data show that protection with rBPI21 is associated with reductions in bacterial counts and is enhanced by antibiotics. Bactericidal activity, in addition to antiendotoxin activity, is involved in the efficacy of rBPI21 in models of gram-negative infection.