Higher-order transverse modes of ultrashort isodiffracting pulses

We present a family of space-time nonseparable analytic solutions describing spatiotemporal dynamics of isodiffracting single-cycle and few-cycle pulses with Hermite-Gaussian and Laguerre-Gaussian transverse profiles. These solutions are space-time localized wave packets propagating in free space. The transverse field profile acts as a spatially dependent filter, modifying the pulse spectrum and removing certain frequencies. The consequences of those effects in the time domain are the distortions of pulse envelope and temporal wave form and the creation of "dark pulses" at certain transverse positions. In addition, due to the space-time coupling, the instantaneous transverse field pattern changes inside the pulse, as well as with propagation distance. These higher-order mode solutions can be used to analyze reflected or scattered terahertz pulses, and to understand the wave-form distortions of terahertz signals in applications. They are also capable of modeling pulsed fields of phase locking of both transverse and longitudinal modes in total mode-locked lasers.

Effects of emulsifiers on the controlled release of paclitaxel (Taxol) from nanospheres of biodegradable polymers

Paclitaxel (Taxol) is an antineoplastic drug effective for various cancers especially ovarian and breast cancer. Due to its high hydrophobicity, however, an adjuvant such as Cremophor EL has to be used in its clinical administration, which causes serious side-effects. Nanospheres of biodegradable polymers could be an ideal solution. This study investigates the effects of various emulsifiers on the physical/chemical properties and release kinetics of paclitaxel loaded nanospheres fabricated by the solvent extraction/evaporation technique. It is shown that phospholipids could be a novel type of emulsifiers. The nanospheres manufactured with various emulsifiers were characterized by laser light scattering for their size and size distribution; scanning electron microscopy (SEM) and atomic force microscopy (AFM) for their surface morphology; zeta potential analyser for their surface charge; and, most importantly, X-ray photoelectron spectroscopy (XPS) for their surface chemistry. The encapsulation efficiency and in vitro release profile were measured by high performance liquid chromatography (HPLC). It is found that dipalmitoyl-phosphatidylcholine (DPPC) can provide more complete coating on the surface of the products which thus results in a higher emulsifying efficiency compared with polyvinyl alcohol (PVA). Our result shows that the chain length and unsaturation of the lipids have a significant influence on the emulsifying efficiency. Phospholipids with short and saturated chains have excellent emulsifying effects.

RAPD-PCR typing of Acinetobacter isolates from activated sludge systems designed to remove phosphorus microbiologically

AIMS

This study investigated whether there were differences in RAPD fingerprints between already described genomic species of Acinetobacter and those from activated sludge systems. Whether plant-specific populations of acinetobacters exist was also examined.

METHODS AND RESULTS

Fifty-two isolates of Acinetobacter from four biological phosphorus removal (EBPR) systems of different configurations, and the known genomic species, were characterized using RAPD-PCR, and fragments separated on agarose gels. Patterns were analysed using Gel Pro software and data analysed numerically. RAPD-PCR produced patterns suggesting that many environmental isolates differ from known genomic species. In two cases, strains from individual plants clustered closely enough together to imply that there may be plant-specific populations of acinetobacters.

CONCLUSION

The data suggest that current understanding of the taxonomic status of Acinetobacter may need modifying to accommodate non-clinical isolates, as many of the clusters emerging after numerical analysis of RAPD-PCR fragments from activated sludge isolates were quite separate from the clusters containing the already described genomic species. Some evidence was also obtained from the clusters generated to support a view that particular populations of Acinetobacter may occur in individual activated sludge plants.

SIGNIFICANCE AND IMPACT OF THE STUDY

These data suggest that the current understanding of the systematics of Acinetobacter, based as it is almost exclusively on clinical isolates, may need drastic revision to accommodate environmental strains. They also suggest that a re-examination of the importance and role of Acinetobacter in the activated sludge process may be appropriate.

New materials in hydrothermal synthesis

In this Account we describe the hydrothermal synthesis of some new materials including microporous crystals, ionic conductors, complex oxides and fluorides, low-dimensional aluminophosphates, inorganic-organic hybrid materials, and particularly condensed materials such as diamond and inorganic helical chains. Hydrothermal synthesis in biology and environment sciences is also introduced. The increasing interest in hydrothemal synthesis derives from its advantages in terms of high reactivity of reactants, easy control of solution or interface reactions, formation of metastable and unique condensed phases, less air pollution, and low energy consumption.

Analysis of methadone and its metabolites in meconium by enzyme immunoassay (EMIT) and GC-MS

An EMIT-ETS d.a.u. immunoassay screening method for methadone in meconium and a gas chromatography-mass spectrometry (GC-MS) method for methadone and its metabolites including 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and 2-ethyl-5-methyl-3,3-diphenylpyrroline (EMDP) in meconium were described. The GC-MS method showed good linearity (r2 > or = 0.998) over a concentration range of 25-2000 ng/g with limits of detection of 10, 25, and 10 ng/g for methadone, EDDP, and EMDP, respectively, and a limit of quantitation of 25 ng/g for all three analytes. Fifty pooled meconium samples were screened using a cutoff of 200 ng/g, and all samples screened negative. GC-MS analysis of all samples showed four samples to contain methadone (35.2 to 79.9 ng/g), EDDP (28.5 to 557.2 ng/g), or both, with no detectable amount of EMDP. The negative results on the four specimens at the cutoff used may be explained by the fact that EMIT-ETS d.a.u. antibody for methadone was specific to the parent drug. The results point to the fact that immunoassays should be directed to EDDP for detection of prenatal exposure of methadone through analysis of meconium specimens.

[The association and linkage analysis between the FcgammaR II a-131 and system lupus erythematosus]

OBJECTIVE

To shed light on the relationship between FcgammaR II a-131 and systemic lupus erythematosus(SLE) in southern Chinese Han population.

METHODS

A population-based and family-based study was carried out. FcgammaR II a-131 of each subject was measured by using PCR-allele specific oligonucleotide hybridization(ASO) method.

RESULTS

(1) The distribution of FcgammaR II A-131 genotype in cases is significantly different from that in controls (P<0.05). So is the frequency of FcgammaR II aR-131 allele (P < 0.01) which suggests that subjects who have R131 allele tend to be more susceptible to SLE. The subjects with R/R131 homozygous genotype have a higher risk of suffering from SLE. (2) The distribution of FcgammaR II a-131 varies in different races, with identical distribution type among Chinese and Japanese. (3) The results of family-based association analysis and transmitted/disequilibrium test(TDT) suggest that there is not any linkage evidence between FcgammaR II a-131 and SLE. Possibly, the sample size was too small to get positive result.

CONCLUSION

This study suggests that FcgammaR II a-131 is a major factor predisposing to the development of SLE in southern Chinese Han population.

Cavity phase engineering for stable enhanced terahertz pulse trains

We show that the cavity round-trip Gouy phase leads to pulse-to-pulse variation of the absolute phase and temporal profile of circulating few- or single-cycle pulses in empty resonators. This pulse-to-pulse variation can be eliminated by the proper insertion of a lens into the cavity. An application to terahertz resonators with phase-locked feedback is discussed.

[Evaluation of derma and fat combined pedicled superficial temporal fascia flap for reconstruction of facial depression]

OBJECTIVE

To evaluate the curative effect of derma and fat combined pedicled superficial temporal fascia flap for reconstruction of facial depression.

METHOD

Postoperative follow-up and comparative study were performed. 10 cases of facial depression deformities were involved, in which 5 cases were hemifacial atrophy, and 5 cases were branchial arch maldevelopment.

RESULTS

Postoperative follow-up for 1-3 years showed that the method produced better results in branchial arch depression than in hemifacial atrophy. The combined tissue used in plomb of branchial arch maldevelopment had a low ratio of anaphase absorption, maintaining a satisfactory long-term full contour. In plomb of hemifacial atrophy, the anaphase absorption ratio of the was combined tissue approximately 20%-40%.

CONCLUSIONS

The noxa of depression ought to be noticed when this method is used in reconstruction of facial depression. The exorbitant plomb is inadvisable for facial depression of branchial arch maldevelopment. However, in facial depression of hemifacial atrophy, in considering anaphases absorption, the suitable exorbitant plomb is reasonable for better future results.

Simultaneous analysis of delta9-THC and its major metabolites in urine, plasma, and meconium by GC-MS using an immunoaffinity extraction procedure

A simple extraction procedure for delta9-tetrahydrocannabinol (delta9-THC) and its metabolites from various biological specimens was developed based on immunoaffinity chromatography. Using the affinity resin prepared by immobilization of THC antibody onto cyanogen bromide-activated Sepharose 4B, delta9-THC and its major metabolites including 11-nor-delta9-THC-9-carboxylic acid (delta9-THCCOOH), 11-hydroxy-delta9-THC (11-OH-delta9-THC), and 8beta,11-dihydroxy-delta9-THC (8beta,11-diOH-delta9-THC) were extracted simultaneously from plasma or urine after enzyme hydrolysis. The samples were derivatized as TMS derivatives and analyzed by gas chromatography-mass spectrometry in EI mode with SIM monitoring. Greater than 87% extraction recovery of the four analytes was obtained from both plasma and urine at 5 and 50 ng/mL concentration levels. The method was also used for meconium analysis with some modification. The extraction recovery from meconium, however, was lower than that of plasma and urine, ranging from 52 to 72% at the 10-ng/g level. All compounds showed good linearity within the tested ranges up to 100 ng/mL (g). The limits of detection ranged from 0.5 to 2.5 ng/mL in plasma and urine, and from 1.0 to 2.5 ng/g in meconium. Analysis of 24 meconium specimens showed that 11-OH-delta9-THC is indeed an important metabolite in meconium.

Endothelial-like cells from the bovine placental cotyledon

A cell-line was established from bovine placental cotyledon. When cultured in M199 with 10% fetal bovine serum, this cell-line had a doubling time of about 18 h. With immunohistochemistry, it was demonstrated that this cell-line expressed vimentin and angiotensin-converting enzyme (ACE). While both molecules are expressed in endothelial cells, ACE is usually considered to be a specific marker for endothelial cells. Furthermore, cells were shown to take up Dil-Ac-LDL (acetylated low-density lipoprotein labeled with 1,1'-dioctadecyl-3,3,3'-tetramethylindo-carbocyanine perchlorate). This characteristic feature has been used to identify endothelial cells. Finally, when cultured on matrigel, this cell-line formed tube-like structures similar to those formed by endothelial cells. Tube-formation on matrigel is a physiological property specific to endothelial cells. In conclusion, these three lines of evidence strongly suggest that this cell-line is endothelial cell in nature. Further studies using an endothelial cell-line from bovine placenta may help to elucidate the cause of bovine placental retention, a major cause for economic loss in bovine industry. Furthermore, an endothelial cell-line could be an important tool in research areas such as tissue remodeling, angiogenesis, and cancer.

In vivo and in vitro modulation of immune stimulatory capacity of primary dendritic cells by adenovirus-mediated gene transduction

Dendritic cells (DCs) are potent antigen-presenting cells which are key leukocytes in the initiation of cell-mediated organ graft rejection, antiviral immunity, and antitumor responses. In this study we demonstrate that genetic modification of primary human and mouse DCs by adenoviral gene transfer is an effective means of induction and modulation of antigen presentation by DCs. An adenovirus vector (AdLacZ) was used to express an intracellular model antigen beta-galactosidase (beta-gal) in DCs. Our results show that 30-40% of precursor dendritic cells (PDCs) derived from human umbilical cord blood and circulating mature blood DCs express high levels beta-galactosidase (beta-gal) after infection with AdLacZ with no cytopathic effect observed. In vitro, AdLacZ transduced PDCs and DCs demonstrated a 10- to 20-fold higher mixed lymphocyte reaction (MLR) stimulatory capacity as compared to that of monocytes. In vivo, immunization with AdLacZ transduced mouse DCs resulted in more potent cytotoxic T lymphocyte (CTL) responses against the predicted H-2 restricted beta-gal epitope as compared to CTL responses obtained by beta-gal peptide pulsed DCs. Modulations of the MLR stimulatory capacity of DCs were examined by expression of mouse B7 and CTLA-4Ig. The results show that expression of mouse B7 by a recombinant adenoviral vector (Ad7) significantly enhances the MLR stimulatory capacity of human DCs. In contrast, expression of CTLA-4Ig (AdCTLA-4Ig) reduces the MLR stimulatory capacity of the transduced cells. We conclude that recombinant adenovirus can readily be used for genetic modulation DC-induced immune responses in vivo and in vitro. DCs targeted for induction of specific antigen responses or for modulation of the immune stimulatory capacity may have a potential use in the control of transplantation rejection or viral infections.

[The impact of hepatitis B virus infected patients or donors on the outcome of hematopoietic stem cell transplantation]

OBJECTIVE

To investigate the impact of recipients and/or donors infected with hepatitis B on the outcome of hematopoietic stem cells transplantation (HSCT).

METHODS

We analyzed retrospectively the transplantation outcome in 26 of 164 hematological diseases patients who and whose donors were infected with hepatitis prior to transplantation.

RESULTS

(1) Three of the 26 patients developed VOD after HSCT, the incidence (11.5%) is significant higher than that in patients and donors who did not infected with HBV (P < 0.05). (2) Two of 5 patients transfused hematopoietic stem cells from HBsAg + donors developed hepatitis B. (3) Four patients with allogeneic stem cell transplantation developed hepatic failure (HF) which occurred during cyclosporin (CsA) being tapered off or withdrawal. The incidence of HF in patients and/or donors infected with HBV (15.4%) is obviously higher than that in patients and donors who did not (0.08%, P < 0.01). (4) In 4 patients with HbeAg +, 2 patients died of HF after allogeneic HSCT, the other 2 patients survived after autologous HSCT.

CONCLUSION

Donors and recipients infected with hepatitis B are not contraindication of HSCT, but patients with allogeneic HSCT are in danger to develop LF during CsA being tapered off or withdrawal.

Lyme arthritis resolution with antiserum to a 37-kilodalton Borrelia burgdorferi protein

A 37-kDa protein from Borrelia burgdorferi (the agent of Lyme disease) was identified as a target for immune-mediated resolution of Lyme arthritis. Studies in a mouse model have shown that arthritis resolution can be mediated by antibodies (against unknown target antigens) within immune sera from actively infected mice. Immune sera from infected mice were therefore used to screen a B. burgdorferi genomic expression library. A gene was identified whose native product is a putative lipoprotein of approximately 37 kDa, referred to here as arthritis-related protein (Arp). Active and passive immunization of mice with recombinant Arp or Arp antiserum, respectively, did not protect mice from challenge inoculation. However, when Arp antiserum was administered to severe combined immunodeficient (SCID) mice with established infections and with ongoing arthritis and carditis, treatment selectively induced arthritis resolution without affecting the status of carditis or influencing the status of infection, including spirochetemia. The selective arthritis-resolving effect of Arp antiserum mimics the activity of immune serum from immunocompetent mice when such serum is transferred into SCID mice with established infections. The arp gene could not be amplified from unrelated B. burgdorferi isolates but hybridized with those isolates only under very-low-stringency conditions. Arp antiserum reacted against proteins of similar size in a wide range of B. burgdorferi isolates.

Electrophoretic affinity chromatography: method validation

A new method for preparative-scale separation of biomolecules, electrophoretic affinity chromatography (EAC), is proposed in this paper. Separation by EAC is carried out in a long and ribbon-like multicompartment electrolyser separated by membranes, in which the two central compartments are used for packing the gel matrix and for sample loading respectively. Next to the central compartments are the elution compartments and electrode compartments. The electric field is applied perpendicular to the fluid flow in the compartments. Adsorption and desorption steps may both be carried out in the presence of an electric field, which transports the target components into the gel compartment for adsorption and the impurities into the elution compartments for washing. After the adsorption step an elution solution is introduced and the product is released from the gel matrix and washed out. Separation of human serum albumin (HSA) from human serum gives HSA product of high purity, as demonstrated by isoelectric focusing analysis. The characteristics of electrophoretic binding of HSA on Blue Sepharose Fast Flow are examined. The preliminary results show that this new method has advantages in terms of high rate of mass transfer and ease of scaling up, which are of particular interest when large-scale separation of biomolecules is considered.

No correlation of polymorphism of angiotensin-converting enzyme genes with left ventricular hypertrophy in essential hypertension

To investigate the correlation of polymorphism of angiotensin-converting enzyme (ACE) genes with left ventricular hypertrophy in essential hypertension, 151 patients with essential hypertension were studied. ACE genotypes were determined by PCR technology and diastolic left ventricular diameter (DLVd), systolic left ventricular diameter (SLVd), interseptal ventricular thickness (IVS), and left ventricular posterior wall thickness (LVPW) were scanned by echocardiography. Left ventricular mass (LVM) and the left ventricular mass index (LVMI) were calculated from echocardiographic findings. Results revealed that DLVd, SLVd, IVS, LVPW, LVM, and LVMI of the DD genotype group were 49.9 +/- 5.6 mm, 30.5 +/- 6.5 mm, 11.2 +/- 1.6 mm, 11.7 +/- 1.5 mm, 259.5 +/- 62.1 g, 92.7 +/- 23.5 g/m2, respectively. DLVd, SLVd, IVS, LVPW, LVM, and LVMI of the ID genotype group were 8.9 +/- 5.3 mm, 31.5 +/- 5.2 mm, 11.4 +/- 1.7 mm, 11.9 +/- 1.6 mm, 261.3 +/- 70.3 g, and 94.9 +/- 25.8 g/m2, respectively, and DLVd, SLVd, IVS, LVPW, LVM, and LVMI of the II genotype group are 48.9 +/- 5.5 mm, 31.8 +/- 6.5 mm, 11.1 +/- 1.9 mm, 11.5 +/- 1.8 mm, 250.8 +/- 82.5 g and 90.8 +/- 30.1 g/m2 respectively. There was no significant difference between the ID, DD and II genotype groups as regards DLVd, SLVd, IVS, LVPW, LVM, and LVMI (p > 0.05). These findings indicate that there is no association between the ACE gene and left ventricular hypertrophy in essential hypertension occurring in the Chinese population.

The galE gene of Campylobacter jejuni is involved in lipopolysaccharide synthesis and virulence

Lipopolysaccharide (LPS) is one of the main virulence factors of gram-negative bacteria. The LPS from Campylobacter spp. has endotoxic properties and has been shown to play a role in adhesion. We previously cloned a gene cluster (wla) which is involved in the synthesis of the Campylobacter jejuni 81116 LPS molecule. Sequence alignment of the first gene in this cluster indicated similarity with galE genes. These genes encode a UDP-glucose 4-epimerase, which catalyzes the interconversion of UDP-galactose and UDP-glucose. A Salmonella galE mutant was transformed with the galE gene from C. jejuni. The LPS analysis of wild-type, galE, and complemented galE Salmonella strains showed that the C. jejuni galE gene could restore the smooth wild-type Salmonella LPS. A UDP-glucose 4-epimerase assay was used to demonstrate that the galE gene from C. jejuni encoded this epimerase. We constructed a C. jejuni galE mutant which expressed a lipid A-core molecule of reduced molecular weight that did not react with antiserum raised against the parental strain. These results show an essential role for the galE gene in the synthesis of C. jejuni LPS. The galE mutant also showed a reduction in its ability to adhere to and invade INT407 cells. However, it was still able to colonize chickens to the same level as the wild-type strain. The serum resistance and hemolytic activity of this mutant were not changed compared to the parent strain. The ability of the mutant to take up DNA and integrate it in its genome was reduced 20-fold. These results show that LPS of C. jejuni is an important virulence factor.

A dendritic cell line genetically modified to express CTLA4-IG as a means to prolong islet allograft survival

BACKGROUND

Dendritic cells are potent antigen-presenting cells that bind allogeneic T cells. They are thus candidates for targeting immunoregulatory molecules to the alloreactive T cell compartment and suppressing the alloimmune response.

METHOD

A dendritic cell line derived from the BALB/c mouse (H2d) was genetically modified to express the immunoregulatory molecule CTLA4-Ig. The ability of these dendritic cell transfectants to downregulate the alloimmune response was tested in an islet transplant model. Allogeneic C57Bl/6 (H2b) mice were rendered diabetic with streptozocin, and they received BALB/c islet (H2d) transplants. Mice were administered 25 million untransfected or CTLA4-Ig-transfected D2SC/1 cells i.v. on the day of islet transplantation and 6 days later[fnc].

RESULT

Mice treated with CTLA4-Ig-transfected D2SC/1 cells demonstrated prolonged allograft survival (mean = 20 days, median = 17 days, SD = 9.39) compared with mice treated with untransfected D2SC/1 cells (mean = 12 days, median = 11 days, SD=2.74) or untreated control mice (mean = 11 days, median = 11 days SD = 1.41). Third party allograft survival was not prolonged in mice receiving similar treatment.

CONCLUSIONS

These results demonstrate that a genetically modified dendritic cell line can suppress the alloimmune response and prolong islet allograft survival in an allospecific manner. The findings also suggest that genetically modified dendritic cells may be useful in targeting alloreactive T cells and prolonging allograft survival.

Interaction of PIP(2) with the XIP region of the cardiac Na/Ca exchanger

The sarcolemmal Na/Ca exchanger undergoes an inactivation process in which exchange activity decays over several seconds following activation by the application of Na to the intracellular surface of the protein. Inactivation is eliminated by an increase in membrane phosphatidylinositol 4,5-bisphosphate (PIP(2)). Inactivation is also strongly affected by mutations to a basic 20-amino acid segment of the exchanger known as the endogenous XIP region. The hypothesis that PIP(2) directly interacts with the XIP region of the exchanger was tested. First, we investigated the ability of a peptide with the same sequence as the XIP region to bind to immobilized phospholipid vesicles. (125)I-labeled XIP bound avidly to vesicles containing only a low concentration (<3%) of PIP(2). The binding was specific, in that binding was not displaced by other basic peptides. The effects of altering the sequence of XIP peptides also indicated binding specificity. Second, we examined the functional response to PIP(2) of exchangers with mutated XIP regions. Outward Na/Ca exchange currents were measured using the giant excised patch technique. The mutated exchangers either had no inactivation or accelerated inactivation. In both cases, the exchangers no longer responded to PIP(2) or to PIP(2) antibodies. Overall, the data indicate that the affinity of the endogenous XIP region for PIP(2) is an important determinant of the inactivation process.

[Kinetic fluorimetric determination of trace oxalate]

A new kinetic fluorimetric method for the determination of trace oxalate is described. The method is based on the enhancing effect of oxalate on the oxidation of butyl rhodamine B by potassium dichromate in the solution of hydrochloric acid. The linear range of the determination is 1.20-10.0 micrograms.mL-1. This method has been used to determine trace oxalate in spinach with satisfactory results.

[Effect of Bacillus megaterium on Gluconobacter oxydans in mixed culture]

To reveal the relationship between Bacillus megaterium and Gluconobacter oxydans in the mixed culture of vitamin C two-step fermentation, the effect of B. megaterium on the growth of G. oxydans and its synthesizing ability of 2-keto-L-gulonic acid(2KGA) was studied. The bioactive metabolites which could enhance the synthesis of 2KGA were isolated and purified by ultrafiltration, gel chromatography and SDS-polyacrylamide gel electrophoresis. Both the culture supernatant and the cytosol of B. megaterium could promote the proliferation of G. oxydans, and the active component in the culture supernatant was above 100 KDa. The culture suernatant could enhance the conversion of L-sorbose to 2KGA, while the cytosol could not. The active components in B. megaterium culture supernatant had molecular weight of 30-50 KDa and above 100 KDa, and the former was a kind of protein with an apparent molecular weight of about 35 KDa, which consisted of one sort of subunit and contained Fe and Zn elements.

Stability of Borrelia burgdorferi outer surface protein C under immune selection pressure

Outer surface protein (Osp) C immune pressure during persistent infection with Borrelia burgdorferi was examined in relation to genetic variation of ospC. Mice were infected with clonal B. burgdorferi sensu stricto (s.s.) N40 or B. afzelii PKo and then were hyperimmunized with homologous recombinant OspC or with decorin-binding protein A (DbpA) (controls). After 6 months, B. burgdorferi isolates were subjected to restriction enzyme analysis of the amplified ospC genes and were found to have no differences among 9 B. burgdorferi s.s. N40 and 9 B. afzelii PKo isolates from OspC hyperimmune mice or among 10 B. burgdorferi s.s. N40 and 10 B. afzelii PKo isolates from DbpA hyperimmune mice, compared with input inocula. Comparison of gene sequences among 4 B. burgdorferi s.s. N40 and 9 B. afzelii PKo isolates from OspC-immunized mice revealed no ospC variation from input inocula. Variation in ospC among B. burgdorferi isolates and species during chronic infection is not likely to be an important mechanism for immune evasion.

Decreased bone mineral density in female patients with systemic lupus erythematosus after long-term administration of Tripterygium Wilfordii Hook. F

OBJECTIVE

To investigate the possible bone changes in female patients with systemic lupus erythematosus (SLE) induced by long-term administration of Tripterygium Wilfordii Hook. F (TW).

METHODS

70 female SLE patients were divided into 4 groups according to their drug history: SLE disease control group, corticosteroids treatment group, TW treatment group, and both corticosteroids and TW treatment group. Bone mineral density (BMD) of the lumbar spine 2-4 and biochemical markers of bone turnover were studied.

RESULTS

Long-term administration of TW could significantly decrease BMD levels in female SLE patients (P < 0.05). The patients receiving TW for more than 5 years had significantly lower BMD levels compared with those for less than 5 years. The degree of decreased BMD induced by TW was less severe compared with that of prednisone. No significant differences were observed in the biochemical markers of bone turnover among four groups (P > 0.05).

CONCLUSION

Long-term administration of TW could decrease BMD levels in women. Osteoporosis may be an important problem for SLE patients treated with TW.

[Treatment of acute lymphoblastic leukemia by autologous stem cell transplantation: an analysis of 30 cases]

OBJECTIVE

To evaluate the clinical outcome of autologous stem cell transplantation (ASCT) in acute lymphoblastic leukemia (ALL) and the affected factors.

METHODS

Data of 30 ALL patients received ASCT in our hospital between July 1987 and December 1997 were retrospectively analyzed. Twenty-four of them were in the first complete remission (CR(1)) and six in the second complete remission (CR(2)) or early relapse (ER). Conditioning regimens were CTX 120 mg/kg + single total body irradiation 9 - 10 Gy (sTBI) or Bu 16 mg/kg of Mel 140 - 180 mg/m(2) + Ara-c 2 - 4 g/m(2).

RESULTS

All patients reconstituted hematopoiesis. The median follow-up duration was 504 (18-3043) days. Transplant-related mortality was 10%. The probabilities of 3 year disease-free survival (DFS) for ALL in CR(1) and CR(2) were 67.7% +/- 10.3% and 16.7% +/- 15.2%, respectively (P = 0.00547); the 3 year DFS was significantly better with posttransplant treatment than without it (92.3% +/- 7.4% vs 50.0% +/- 17.7%, P = 0.0130).

CONCLUSION

Acute lymphoblastic leukemia patients without HLA-matched related donor are recommended for ASCT in CR(1). To reduce relapse and improve the outcome, adoptive immunotherapy or maintenance chemotherapy should be given after ASCT.

Basal lamina of avian ovarian follicle: influence on morphology of granulosa cells in-vitro

Experiments were conducted to determine the influence of basal lamina on the morphology of ovarian granulosa cells in vitro. Pure and intact basal lamina was isolated from the large preovulatory follicles of the chicken ovary and designated basal lamina of avian ovarian follicle (BLAOF). Examination of the isolated basal lamina with electron microscope revealed an ultrastructure that is similar to that of basal lamina in the intact ovarian follicle. Pieces of the intact basal lamina were attached to the bottom of 32 mm culture dishes (BLAOF-coated dishes) in which differentiated granulosa cells isolated from the largest preovulatory follicle or undifferentiated granulosa cells isolated from immature small yellow chicken ovarian follicles were cultured; uncoated dishes served as controls. Granulosa cells incubated on intact basal lamina assumed spherical shape, whereas granulosa cells incubated directly on plastic in control dishes became highly flattened. Interestingly, granulosa cells that attached to plastic close to BLAOF (in BLAOF-containing dishes) became rounded. The storage of BLAOF-coated culture dishes at 4 degrees C for 2 years had no apparent effect on its ability of the matrix material to induce changes in granulosa cell shape. Some components of the basal lamina could be solubilized with guanidine-HCl alone (fraction 1; 90-95% of total protein in BLAOF) with the remaining components solubilized with beta-mercaptoethanol containing guanidine-HCl (fraction 2; 5-10% of total protein in BLAOF). Differentiated and undifferentiated chicken granulosa cells became rounded when incubated in fraction 1-pre-coated wells; whereas those incubated directly on plastic in control wells were flattened. Similarly, when fraction 1 of solubilized basal lamina was added as liquid to incubation mixture, it caused both differentiated and undifferentiated granulosa cells to assume spherical shapes. The storage of fraction 1-coated culture dishes at 4 degrees C for 12 or more months had no apparent effect on its ability to influence granulosa cell shape. Fraction 1-induced changes in granulosa cell shape were similar to those observed for complete and intact basal lamina (BLAOF). These findings demonstrate that intact homologous basal lamina (BLAOF) or its solubilized (fluidized) form can induce normal (in vivo) morphology in granulosa cells. It is suggested that BLAOF or its solubilized form can be used to culture cells in experiments designed to examine the influence of the natural basal lamina microenvironment on cellular behavior and function.

Cytoplasmic domains of GpIbalpha and GpIbbeta regulate 14-3-3zeta binding to GpIb/IX/V

Shear stress causes the platelet glycoprotein (Gp) Ib/IX/V to bind to von Willebrand factor, resulting in platelet adhesion. GpIb/IX/V also functions to stimulate transmembranous signaling, leading to platelet activation and the expression of a ligand-receptive GpIIb-IIIa complex. The highly conserved cytoplasmic domain of GpIbalpha binds directly to a dimeric 14-3-3 adapter protein zeta isoform. To explore structural determinants of GpIb/IX/V binding to 14-3-3zeta, the authors examined 14-3-3zeta interactions with GpIbalpha and GpIbbeta in heterologous cells and platelets. Truncations of GpIbalpha at amino acid 542 or 594, or deletions of residues 542 through 590, inhibited binding of 14-3-3zeta. Deletion of GpIbalpha from Trp(570) to Ser(590) eliminated 14-3-3zeta binding, and deletion of the sequence from Arg(542)-Trp(570) enhanced binding of 14-3-3zeta to GpIbalpha. All GpIbalpha mutations that eliminated GpIbalpha binding to the GST-14-3-3zeta fusion protein also eliminated GpIbbeta binding to the fusion protein. Forskolin treatment of Chinese hamster ovary cells expressing wild-type GpIbalpha/beta/IX resulted in the phosphorylation of GpIbbeta associated with enhanced binding of GpIbbeta to GST-14-3-3zeta fusion protein and increased 14-3-3zeta coimmunoprecipitated with GpIbalpha. When intact human platelets aggregated in response to 90 dynes/cm(2) shear stress, 14-3-3zeta disassociated from GpIbalpha. Prostacyclin treatment of platelets inhibited shear stress-induced aggregation and the release of 14-3-3zeta from GpIbalpha. These data demonstrate that amino acid residues in the cytoskeletal interaction domains of GpIbalpha regulate 14-3-3zeta binding to GpIbalpha/beta/IX, and suggest that protein kinase A-dependent phosphorylation of GpIbbeta enhances 14-3-3zeta binding to the GpIb/IX/V complex in human platelets. (Blood. 2000;95:551-557)

Spatiotemporal structure of isodiffracting ultrashort electromagnetic pulses

We present a model of isodiffracting single-cycle and few-cycle ultrashort electromagnetic pulses. The model is based on exact solutions of the time-dependent paraxial wave equation with space-time coupling effects included. The spatiotemporal structure of these pulses is characterized by a scaling parameter which relates off-axis pulse shapes to the axial temporal waveforms. Depending on the spectrum a pulse may transform itself from a single-cycle pulse to a multicycle pulse along the radial coordinate. This model is also used to describe recirculating pulses in a curved mirror cavity resonator. The Gouy phase shift contributes an absolute phase that results in a pulse-to-pulse temporal instability.

Isolation and mapping of rFUS6, a rice orthologue of Arabidopsis thaliana FUS6

COP9 complex is one of the most important components that act in repressing photomorphogenesis in Arabidopsis thaliana. FUS6 has been identified as one of eight subunits of the COP9 complex in Arabidopsis. Using Arabidopsis Fus6 cDNA as a probe, we screened a rice root cDNA library and a rice genomic library. A 1730-bp cDNA was obtained, which has an open reading frame corresponding to 441-amino-acid. This 441 amino acids putative protein has 67% identity with Arabidopsis COP11/FUS6 (AtFUS6) and 40% identity with human GPS1, an AtFUS6 orthologue. So we designated this novel gene as rFUS6. The 6.2-kb genomic sequence of rFUS6 was also obtained. Sequence comparison showed that the rFUS6 gene had six exons and five introns. Sequence inspection of the 5'-flanking region revealed the presence of some potential light-regulated cis-elements such as a G-box, GT-1 binding sites, and a TGACG motif. Southern hybridization with rice total DNA showed that rFUS6 was perhaps a single copy gene. The rFUS6 locus was mapped by hybridization with a rice BAC library membrane and the results showed that rFUS6 had a locus at 16.3 cM of chromosome 1.

The effect of electroacupuncture on auditory P300 potential in mongolism cases

In treating children with mongolism (Down's syndrome) with electroacupuncture, the latent period of P3 is shortened, which shows that the cerebral reaction to external stimulus in classification, encoding and recognition is accelerated. Along with the elevated P3 amplitude, the cerebrum is more capable of processing the external information, showing improvement of the mental state.

Identification and analysis of the major metabolites of cocaine in meconium

A gas chromatographic-mass spectrometric (GC-MS) method was used for the simultaneous analysis of cocaine and its metabolites (norcocaine, benzoylecgonine, norbenzoylecgonine, ecgonine methylester, cocaethylene, and the o-, m, and p-hydroxy derivatives of cocaine and benzoylecgonine) in meconium specimens collected from newborns prenatally exposed to the drug in an effort to determine which of these metabolites are more relevant in the confirmation of immunoassay-positive specimens. Significant metabolites included benzoylecgonine and its m- and p-hydroxy derivatives. Reanalysis of immunoassay-positive meconium specimens that previously failed to confirm by GC-MS for benzoylecgonine revealed that the GC-MS confirmation rate could be substantially enhanced by inclusion of m- and p-hydroxybenzoylecgonine in the analysis along with benzoylecgonine. Several specimens were found to be positive for hydroxylated derivative(s) in the absence of benzoylecgonine itself.

GC-MS determination of flunitrazepam and its major metabolite in whole blood and plasma

A gas chromatography-mass spectrometry method was developed for the analysis of flunitrazepam (FN) and its major metabolite, 7-amino-flunitrazepam (7-amino-FN), in both plasma and whole blood. The method was based on acid hydrolysis of the samples after dilution with HPLC water followed by extraction and derivatization (heptafluorobutyrate) of the resulting benzophenones. Analysis of plasma and whole blood samples from subjects administered 2-mg doses of FN showed that FN was only detected in whole blood (LOD 5 ng/mL) and not in plasma. However, 7-amino-FN was detected in both plasma and whole blood, although the levels were much higher in plasma. 7-Amino-FN was detected for the entire period of specimen collection (12 h), but FN was only detected in whole blood for 4 h after ingestion with peak levels after 1 h.

Relationship of beta-glucuronidase to differentiation and invasion of human colorectal carcinoma

OBJECTIVE

To investigate the relationship between beta-glucuronidase and tumor differentiation and invasion in human colorectal carcinoma.

METHODS

The expression of beta-glucuronidase in human colorectal carcinoma tissue was determined by streptavidin-peroxidase immunohistochemical method. Four human colorectal carcinoma cell lines were analysed for beta-glucuronidase in the medium by spectrophotometry method.

RESULTS

Compared with well differentiated colorectal carcinomas, beta-glucuronidase expression was higher in poorly differentiated tumors. An association was found between beta-glucuronidase overexpression in colorectal carcinoma and more advanced tumor Dukes' stage (P < 0.05). With increasing maximum depth of invasion, tumors more frequently show higher beta-glucuronidase expression (P < 0.05). The analysis of colorectal carcinoma cell lines for beta-glucuronidase showed that low levels of beta-glucuronidase (activity range, 1.29 to 1.96 micrograms/10(6) cells per hour) were associated with the well differentiated cell lines which have low invasiveness (CX1, CCL187), and this was in contrast to the elevated level of the enzyme (2.46 to 2.73 micrograms/10(6) cells per hour) present in the medium derived from the poorly differentiated cells with high invasiveness (CCLI227, CCL228) (P < 0.05).

CONCLUSIONS

Poorly differentiated human colorectal carcinoma cells could synthesize more beta-glucuronidase, enhance local invasion. Immunohistochemical staining for beta-glucuronidase might be helpful to diagnosing the differentiation degree and invasiveness of human colorectal carcinomas, and the secreted beta-glucuronidase might provide a useful measurement of the differentiation degree and invasiveness of cultured human colorectal carcinoma cells.

Experimental studies on affinity chromatography in an electric field

A multicompartment electrolyzer, which has been used for preparative electrophoresis [Z. Liu, Z. Huang, J.-Y. Cong, et al., Sep. Sci. Technol. 31 (1996) 427], is applied for carrying out affinity chromatography in an alternating electric field. The effect of electric field strength on the adsorption and desorption characteristics is experimentally examined with human serum albumin and Blue Sepharose Fast Flow as a model system. It is shown that the existence of an electric field leads to a significant change in the adsorption capacity of the blue dye, which may be used for establishing a preferential adsorption to achieve a high resolution. The adsorption speed increases slightly with respect to the increase of electric field strength, while adsorption capacity in the presence of an electric field is independent of the electric field strength. Different elution behavior is observed as function of adsorption condition and a high recovery of the adsorbed protein is obtained when the adsorption is carried out in the presence of an electric field.

[Comparison of clinical outcome between allogeneic peripheral blood stem cell transplantation and bone marrow transplantation]

OBJECTIVE

To compare the clinical outcome of allogeneic peripheral blood stem cell transplantation(PBSCT) with that of bone marrow transplantation(BMT).

METHODS

Twenty-six patients received allo-BMT and 24 received allo-PBSCT in our hospital between August 1991 and September 1998. Conditioning regimens were CY 120 mg/kg plus STBI 9-10 Gy or BU 16 mg/kg or Mel 140-160 mg/m2 plus CY 120 mg/kg.

RESULTS

Twenty-three patients of PBSCT and 24 of BMT group engrafted successfully. The median follow-up duration was 352(19-745) days for the PBSCT group and 546(19-2,329) days for the BMT group. Transplant-related death was 4(16.7%) patients in the PBSCT and 7(26.9%) in BMT group (P = 0.38). Three(12.5%) patients in PBSCT and 5(19.2%) in BMT group relapsed(P = 0.27). The 2-year probabilities of disease-free survival(DFS) for PBSCT and BMT group were (67.9 +/- 11.3)% and (57.7 +/- 9.7)%, respectively(P = 0.24). aGVHD occurred in 6(25%) patients in the PBSCT and 6 (23.1%) in the BMT group (P = 0.624), while cGVHD did in 13(56.5%) and 1 (3.85%), respectively (P = 0.0002).

CONCLUSION

The clinical outcome of allo-PBSCT is similar to allo-BMT, except for a higher incidence of cGVHD.

[Judging the date of Neijing (Inner Canon) through study on semantic changes]

In the pre - Qin literature, the characters "ti", "pi", "nian" refer to "tear", "beast skin" and "year" respectively and it became "nasal discharge", "man's skin" and "age" respectively in the Han dynasty, which never appeared in the pre - Qin period. By studying the semantic changes in books of different times, the meanings of the above 3 characters, that frequently occurred in Neijing, are identical with those books of the Han dynasty. Hence, it can be concluded that Neijing can only be completed not early than the Han dynasty.

[Pure red cell aplasia after allogeneic peripheral blood stem cell transplantation: a case report and literature review]

OBJECTIVE

To report a case of post-allogeneic peripheral blood stem cell transplantation (allo-PBSCT) pure red cell aplasia(PRCA) and the treatment outcome.

METHODS

A patient with acute non-lymphoblastic leukemia(M2a) was treated with allo-PBSCT. His post-PBSCT PRCA was treated with plasmapheresis(2-3 times weekly) and Epo(3,000 U/day, subcutaneously).

RESULTS

Reticulocyte count (Ret) recovered to 0.01 at day +131 and hemoglobin reached 110 g/L at day +154. Erythroid cells in the bone marrow recovered to 0.25, and BFU-E and CFU-E within normal range. This normalized hematopoiesis remained for over 5 months after the cessation of Epo.

CONCLUSION

Post allo-PBSCT PRCA can be successfully treated with plasma exchange and Epo.

Prolonged xenograft survival of islets infected with small doses of adenovirus expressing CTLA4Ig

BACKGROUND

Systemic administration of the inhibitor of costimulation, CTLA4Ig, has been shown to prolong islet graft survival. The purpose of this study was to compare local and systemic expression of murine CTLA4Ig in transplants of rat islets into mice.

METHODS

Murine CTLA4Ig was made by joining two polymerase chain reaction products, the extracellular portion of CTLA4 and the Fc portion of IgG2a. Recombinant adenovirus expressing CTLA4Ig (AdCTLA4Ig) was generated using the strategy of Cre-lox recombination. Isolated rat islets infected with AdCTLA4Ig at multiplicities of infection (MOIs) ranging from 0.1 to 10 were transplanted into streptozocin diabetic male B6AF1 mice. Control islets were mock infected or infected with AdLacZ or AdsIg, a recombinant adenovirus expressing only the Fc portion of IgG2a. Also, AdCTLA4Ig and control viruses were injected intramuscularly into mouse transplant recipients at the time of islet transplantation to provide CTLA4Ig systemically.

RESULTS

Control islets transplanted into diabetic mice were rejected in 13-17 days. Islets infected with AdCTLA4Ig had dose-dependent prolongation of graft survival. Prolonged survival was even found with very low MOIs of 0.1 and 0.5, with survivals of 24+/-4.2 and 25+/-2.2 days, respectively. Survival with an MOI of 10 was 39+/-8.7 days. With intramuscular injection, no prolongation was found at the lowest relative MOIs of 0.2 and 1, but there was dose-dependent prolongation of graft survival with larger doses. At the highest relative MOI of 400, survival was prolonged to 58+/-10 days.

CONCLUSIONS

Rat islets infected with AdCTLA4Ig transplanted into mice had prolonged graft survival. Prolonged survival with MOIs as low as 0.1 and 0.5 indicates that only a minority of islet cells need to express CTLA4Ig to exert an effect. Moreover, the results suggest that the improved islet graft survival is due to a local influence of CTLA4Ig.

The glycoprotein Ib/IX complex regulates cell proliferation

The glycoprotein (Gp) Ib/IX complex contains three transmembranous leucine-rich repeat polypeptides (GpIbalpha, GpIbbeta, and GpIX) that form the platelet von Willebrand factor (vWF) receptor. GpIb/IX functions to effect platelet adhesion, activation, and aggregation under conditions of high shear stress. GpIb/IX is expressed late in the ontogeny of megakaryocytes, the precursor cell that releases platelets when it reaches its terminal stage of differentiation. Because signal pathways can be reused at different stages of development by integration with different effector pathways and because cellular adhesion through other receptor families often modulates cell growth, the hypothesis that GpIb/IX regulates cell growth was investigated. The surface expression of recombinant GpIbalpha decreases the proliferation of transduced CHO cells. GpIbalpha causes growth arrest in the G1 phase of the cell cycle associated with the induction of the cyclin-dependent kinase inhibitor p21. G1 arrest induced by recombinant GpIbalpha in heterologous cells requires signaling through the 14-3-3zeta binding domain of GpIbalpha and is partially dependent on its engagement by the extracellular ligand vWF. Growth arrest induced by the expression of recombinant GpIb/IX is followed by apoptosis of the transduced cells. The endogenous expression of GpIbalpha in human hematopoietic cells is associated with decreased proliferation. These results suggest that the expression of the GpIb/IX complex regulates megakaryocyte growth.

Preparation and Morphology Studies of Core-Shell Type Waterborne Polyacrylate-Polyurethane Microspheres

Core-shell type waterborne polyacrylate-polyurethane microspheres in which polyurethane acts as the shell and acrylic polymer as the core were prepared. Hydroxyethyl acrylate and adipic dihydrazide were used as cross-linking agents introduced to the ends of the shell molecular chains, and two kinds of cross-linked structures between the core and the shell were formed. The photon correlation spectroscopy studies indicate that all the microspheres present continuous particle-size distributions and their mean particle sizes are smaller than 200 nm. The transmission electron photographs reveal that there are obvious core-shell structures for the noncross-linked type microsphere particles and different cross-linked networks between the core and shell for the two kinds of cross-linked type microsphere particles. These microspheres possess excellent storage stability, water resistance, and coating properties. Copyright 1999 Academic Press.

[Study on masticatory muscles and tooth long axis of miniature pigs]

OBJECTIVE

The similarities of masticatory muscles and teeth orientations between miniature pigs and human beings were studied in order to evaluate the use of miniature pigs in oral biomechanics research.

METHODS

By means of anatomy, the shapes, start-stop points and orientations of muscle of major masticatory muscles of miniature pigs were measured. Inclination of upper and lower teeth long axis was studied with lateral xray film of mandibles.

RESULTS

The main masticatory muscles of miniature pigs include masseter muscle, temptory muscle, lateral pterygoid muscle, medial pterygoid muscle and zygomaticomandibular muscle. The angles of masticatory muscles and base plane are 63.9 degrees in massater muscle, 114.55 degrees in temple muscle, 64.4 degrees in medial pterygoidp muscle. The long axises of miniature pigs teeth are 6.1 degrees in the upper first molar, 6.5 degrees in the lower first molar, 7.3 degrees in the upper third premolar, 3.8 degrees in the lower third premolar.

CONCLUSION

The masticatory muscles of miniature pigs are similar with human being in the shape, start-stop point and orientation of muscle force. The third premolar and the first molar of miniature pigs inclinate mesially, and are similar with the first premolar and the first molar of the human beings. Miniature pigs can be used as an animal models which can explain some problems of gnathostomatic system of human beings.

Phylogenetic position of the kinetoplastids, Cryptobia bullocki, Cryptobia catostomi, and Cryptobia salmositica and monophyly of the genus Trypanosoma inferred from small subunit ribosomal RNA sequences

Phylogenetic relationships within the kinetoplastid flagellates were inferred from comparisons of small-subunit ribosomal RNA gene sequences. These included three new gene sequences from Cryptobia bullocki, (2091 bp), Cryptobia catostomi (2090 bp), and Cryptobia salmositica (2091 bp). Trees produced using maximum parsimony and distance-matrix methods (least squares and neighbor-joining) demonstrated with strong bootstrap support, that the kinetoplastids are a monophyletic group divided into two major lineages consistent with the two suborders, Trypanosomatina and Bodonina. Within the trypanosomatid clade, the genus Trypanosoma is a monophyletic group that divides into two groups, the salivarian trypanosomes and the stercorarian trypanosomes. Dimastigella and Rhynchobodo, currently classified in the Bodonina, are basal to the trypanosomatid-bodonid clade, suggesting that the suborder Bodonina is paraphyletic. Further, Trypanoplasma borreli grouped within the Cryptobia clade, and was more closely related to C. salmositica than to either C. bullocki or C. catostomi. This new molecular evidence, coupled with morphological similarities of the two genera, again calls into question the validity of the genus Trypanoplasma.

[Analysis of patients survived over ten years after resection of gastric cardia carcinoma]

OBJECTIVE

To investigate factors affecting long-term survival in patients with resected gastric cardia cancer.

METHODS

Survival was analyzed retrospectively in 584 patients with gastric cardia carcinoma who received tumor resection from 1964 through 1982.

RESULTS

The 10-year survival rate was 17.1%. The major factors influencing survival were clinical staging, degree of differentiation, gross tumor type and size (P < 0.05) and status of lymph node metatasis (P < 0.01). Residual tumor at resection edge and tumor thrombi did not significantly affect survival, nor did sex/age, and course of the disease.

CONCLUSION

Early detection, early diagnosis and early surgical resection are the key to improve 10-year survival of patients with resected cancer of the gastric cardia. Why residual tumor left at the resection edge and the presence of tumor thrombi do not influence survival needs to be further studied.

Killing effect of interleukin-2 and interferon-alpha activated leukemic bone marrow in remission on K562 leukemic cells

OBJECTIVE

To evaluate the killing effect of interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) activated bone marrow cells on K562 cells.

METHODS

Semi-solid colony and 3H-TdR incorporating method were used.

RESULTS

Bone marrow from leukemia patients in remission was activated in vitro with IL-2 for 3 days. The activated bone marrow (ABM) displayed killing effects of 0.31-2.30 logs on K562 cells. This killing effect was further increased to 0.30-3.15 logs when IFN-alpha added with IL-2 to the marrow for activation. IL-2 alone or in combination with IFN-alpha showed no inhibition of CFU-GM and K562 cells. Compared with IL-2 or IFN-alpha alone, the combination of the two cytokines could more effectively maintain the killing effect of ABM on leukemic cells.

CONCLUSIONS

IFN-alpha can augment the purging effect of IL-2 ABM and combination of the two cytokines can effectively maintain the cytotoxicity of ABM.

GC/MS analysis of m-hydroxybenzoylecgonine in urine. Forensic implication in cocaine use

m-Hydroxybenzoylecgonine (m-OH-BE) and d3-m- hydroxybenzoylecgonine (d3-m-OH-BE) have been synthesized, and a GC/MS procedure with d3-m-OH-BE as internal standard has been developed. Among 24 human urine specimens that were positive for BE, all of them have shown detectable levels of m-OH-BE with 75% of the specimens exceeding the LoQ (5 ng/mL), compared with only 50% of the specimens containing detectable levels of EME. The presence of m-OH-BE in urine suggested that this metabolite may serve as a valuable marker of cocaine use in addition to BE and EME.

Acquisition and transmission of the agent of human granulocytic ehrlichiosis by Ixodes scapularis ticks

The purpose of the present study was to investigate the transmission of a human isolate of the agent of human granulocytic ehrlichiosis (HGE agent) from infected mice to larval ticks and to examine the population kinetics of the HGE agent in different stages of the tick life cycle. The HGE agent was quantitated by competitive PCR with blood from infected mice and with Ixodes scapularis ticks. The median infectious dose for C3H mice was 10(4) to 10(5) organisms when blood from an infected severe combined immunodeficient mouse was used as an inoculum. Uninfected larval ticks began to acquire infection from infected mice within 24 h of attachment, and the number of HGE agent organisms increased in larval ticks during feeding and after detachment of replete ticks. Molted nymphal ticks, infected as larvae, transmitted infection to mice between 40 and 48 h of attachment. Onset of feeding stimulated replication of the HGE agent within nymphal ticks. These studies suggest that replication of the HGE agent during and after feeding in larvae and during feeding in nymphs is a means by which the HGE agent overcomes inefficiencies in acquisition of infection by ticks and in tick-borne transmission to mammalian hosts.