Combinatorial treatment of bone marrow stem cells and stromal cell-derived factor 1 improves glycemia and insulin production in diabetic mice

Transdifferentiation of stem cells into insulin-producing cells for the treatment of diabetes have shown promising but inconsistent results. We examined the potential for attracting bone marrow stem cells (BMSCs) to the pancreas using a chemokine, stromal cell-derived factor 1 (SDF-1). SDF-1 treatment markedly increased the number of GFP labeled BMSCs in the pancreas, but surprisingly, the majority was observed in liver. The liver cells had typical pancreatic endocrine cell gene expression including insulin I, insulin II, PDX-1, somatostatin, and glucagon. Combined treatment with SDF-1 and BMSC transplant reduced hyperglycemia and prolonged the long-term survival of diabetic mice, and a sub group had complete normoglycemia (<150 mg/dl), restored blood insulin levels, and normal glucose tolerance. Our results suggest that SDF-1 could potentially be used to improve the homing of stem cells and β-cell regeneration. The mechanism appears to involve an increase in insulin producing cells mainly in the liver.

Group velocity manipulation in active fibers using mutually modulated cross-gain modulation: from ultraslow to superluminal propagation

We propose and experimentally demonstrate the propagation of slow/fast light in an erbium-doped fiber (EDF) using mutually modulated cross-gain modulation. The group velocity of the light signal can be manipulated by the effect of gain cross-saturation modulation by a saturating light at an arbitrary wavelength in the gain bandwidth of the EDF. The ultraslow propagation with a small group velocity of 5.6 × 10⁻³c (c is the light speed in free space) and superluminal propagation with a negative group velocity of -1.1 × 10⁻³c has been observed under different modulation phases.

Stage-dependent tolerance of the German cockroach, Blattella germanica for dichlorvos and propoxur

tage-dependent dichlorvos and propoxur tolerance in a field population of the German cockroach, Blattella germanica Linnaeus (Blatodea: Blattellidae), was investigated in the laboratory using a topical application bioassay. The results showed the 6 week-old nymphs were more tolerant to dichlorvos and propoxur than the other ages tested. LD₅₀ values of dichlorvos and propoxur for the 6 week-old nymphs were 2.003 µg per insect and 5.296 µg per insect, respectively. Tolerance ratios of 18.55-fold and 4.98-fold for LD₅₀ were obtained from 6-week-old nymphs compared to 4 week-old nymphs. The specific activity of acetylcholinesterase (AChE) from 1 week-old nymphs was the highest among all tested developmental stages of nymphs and adult males and females. The specific activity of AChE decreased significantly with increasing age. The sensitivity of AChE to dichlorvos was the highest with a k(i) value of 3.12 × 10⁴ mol⁻¹min⁻¹ in the last nymphal stage of B. germanica (about 6 weeks-old). The AChE from 4 week-old nymphs was the most sensitive to propoxur, with the highest k(i) value being 2.63 × 10⁵ mol⁻¹ min⁻¹. These results indicated that the different developmental stages and sexes of B. germanica affected the inhibition of AChE by dichlorvos and propoxur.

Efficacy and safety of catnip (Nepeta cataria) as a novel filth fly repellent

Catnip (Nepeta cataria) is known for its pseudo-narcotic effects on cats. Recently, it has been reported as an effective mosquito repellent against several Aedes and Culex species, both topically and spatially. Our laboratory bioassays showed that catnip essential oil (at a dosage of 20 mg) resulted in average repellency rates of 96% against stable flies, Stomoxys calcitrans (L.) and 79% against houseflies, Musca domestica (L.), respectively. This finding suggested that the application of repellent could be used as part of filth fly management. Further evaluations of catnip oil toxicity were conducted to provide a broad-spectrum safety profile of catnip oil use as a potential biting and nuisance insect repellent in urban settings. Acute oral, dermal, inhalation, primary dermal and eye irritation toxicity tests were performed. The acute oral LD(50) of catnip oil was found to be 3160 mg/kg body weight (BW) and 2710 mg/kg BW in female and male rats, respectively. The acute dermal LD50 was > 5000 mg/kg BW. The acute inhalation LD50 was observed to be > 10,000 mg/m3. Primary skin irritation tested on New Zealand white rabbits showed that catnip oil is a moderate irritant. Catnip oil was classified as practically non-irritating to the eye. In comparison with other U.S. Environmental Protection Agency-approved mosquito repellents (DEET, picaridin and p-menthane-3,8-diol), catnip oil can be considered as a relatively safe repellent, which may cause minor skin irritation.

The primary clinical trial of dendritic cell vaccine pulsed with apoptosis tumor cell in patients with malignant cancers

13509

Background: We evaluated the feasibility, safety, and immunogenicity of mature, apoptosis tumor cells-pulsed dendritic cell (DC) vaccines administered by intradermal injection. Methods: We performed a randomized study in 16 patients with malignant tumors, including 4 cases for gastric cancer, 3 cases for prostate cancer, 2 cases for breast cancers, one case for lung cancer, esophageal carcinoma, liver cancer , colorectal cancer, kidney cancer, ovarian cancer, endometrial cancer respectively.The vaccine used mature DCs (CD11c++, HLA-DR++, CD83+, and CD86+++) generated from peripheral blood monocytes in the presence of GM-CSF and IL-4. After 5 days, DCs were matured with a defined cocktail of cytokines (IL-1+ TNF-a+PGE2) and simultaneously pulsed with apoptosis autologous tumor cells or heterologous tumor cell lines, for 2 days.Patients were administrated four DC vaccinations (5×106 per time) at 7th day, 14th day, 21st day and 42nd day by intradermal injection(ID). Toxicity effect, life quality, immune function and clinical efficacy were monitored during the whole therapy. Results: Fourteen (82.4%) of 17 patients completed all four vaccinations. Vaccinations were well tolerated; a few patients exhibited less than grade 1 toxicities including rash, transient fever, transient debilitation and injection site reaction. The life quality of most patients had improved to certain degree, including sleep, appetite, mental status, and a good recovery from surgery and chemotherapy. Moreover, the serum level of IL-2 of 10/14 patients increased more than several times to twenty times, and 6/10 patients had a long increase for more than forty days. Serum level of IL-12 were increase in 11/14(9/11 patients increased for more than forty days) patients, Serum level of IFN-? were increase in 11/14(5/11 patients increased for more than forty days ) patients. Conclusions: Administration of this apoptosis tumor cell-pulsed mature DC vaccine by ID routes is feasible and safe. This administration seems to result in superior immunological sensitization as measured by in vitro serum level of immune cell factor such as IL-2, IL-12 and IFN-?.

No significant financial relationships to disclose.

Expression and preliminary characterization of recombinant human tissue kallikrein in egg white of laying hens

Human tissue kallikrein (hK1) plays an important role in regulation of blood pressure, electrolyte and glucose transport, and renal function. To evaluate the feasibility of expression of recombinant human tissue kallikrein (rhK1) in the egg whites of laying hens, human tissue kallikrein gene (hKLK1) cDNA was subcloned into the chicken oviduct-specific expression vector (pOV3), and the resultant recombinant vector pOV3K was injected into laying hens via wing vein after mixing with polyethyleneimine. Following injection twice with the recombinant vector, the enzymatic activity at a maximal level of 59 U/mL was detected in the egg whites, which lasted for more than 7 d. The expression level of rhK1 in the egg whites in the 3-mg group was relatively higher than that in the 2-mg group, but the significant differences were identified on d 7 and 8 (P < 0.05). Ten days after the primary injection, the hens were reinjected with the same dose of the vector, and even higher enzymatic activity was detected in their egg whites. Two different breeds of hen were tested with no difference in expression level found (P > 0.05). Western blot analysis of the egg whites from vector-injected hens showed the rhK1 was recognized by a polyclonal antibody specific for hK1 with molecular weights of 37 and 43 kDa, which probably corresponded to the mature and preenzyme, respectively. Biochemical studies showed that the recombinant enzyme had a similar thermostability, optimal pH, hypotensive effect, and sensitivity to different ions to the natural enzymes in human and porcine tissues. These data indicate that the chicken oviduct-specific transient expression system can produce relatively high level and authentic recombinant enzyme with a potential for further development for therapeutic use.

A hypoxia-inducible vigilant vector system for activating therapeutic genes in ischemia

Hypoxia represents an endogenous pathophysiological signal underlying cell growth, adaptation and death in a variety of diseases, including ischemic heart diseases, stroke and solid tumors. A vigilant vector system depends on a gene switch which can sense the hypoxia signal occurring in ischemic events and turn on/off protective gene expressions when necessary. This system uses the oxygen-dependent degradation domain derived from hypoxia-inducible factor 1alpha as the hypoxia sensor and a double-vector system as signal amplifier. For treating ischemic heart diseases, a cardiac-specific MLC-2v promoter is used to deliver transgenes specifically to the heart. When tested in cardiomyocyte cultures, it produced a rapid and robust gene induction upon exposure to low oxygen. In a mouse model for myocardial infarction, the vigilant vectors turned on therapeutic genes such as heme oxygenase-1 in response to ischemia, significantly reduced apoptosis in the infarct area and improved cardiac functions. The hypoxia-regulated gene transfer afforded by the vigilant vectors may provide a powerful tool for delivering therapeutic proteins specifically to ischemic tissues with optimal physiological control.

[The application of neural network to output estimation of an impeller artificial heart]

In this paper, several methods of output estimation of artificial heart are introduced briefly, and the authors put forward a method for the application of neural network to the output estimation of an impeller artificial heart. According to the laboratory results, the application of neural network can solve the problem successfully.

Kendrick mass defect spectrum: a compact visual analysis for ultrahigh-resolution broadband mass spectra

At currently achievable Fourier transform ion cyclotron resonance broadband mass spectrometry resolving power (m/deltam50% > 350,000 for 200 < m/z < 1,000), it would be necessary to spread out a conventional mass spectrum over approximately 200 m in order to provide visual resolution of the most closely resolved peaks. Fortunately, there are natural gaps in a typical mass spectrum, spaced 1 Da apart, because virtually no commonly encountered elemental compositions yield masses at those values. Thus, it is possible to break a broadband mass spectrum into 1-Da segments, rotate each segment by 90 degrees, scale each segment according to its mass defect (i.e., difference between exact and nominal mass), and then compress the spacing between the segments to yield a compact display. For hydrocarbon systems, conversion from IUPAC mass to "Kendrick" mass (i.e., multiplying each mass by 14.00000/14.01565) further simplifies the display by rectilinearizing the peak patterns. The resulting display preserves not only the "coarse" spacings (e.g., approximately 1 Da between odd and even masses, corresponding to either even vs odd number of nitrogens or 12C(c) vs 12C(c-1)13C1 elemental compositions of the same molecule; approximately 2-Da separations, corresponding to a double bond or ring; approximately 14 Da separations, corresponding to one CH2 group) but also the "fine structure" (i.e., different mass defects for different elemental compositions) across each 1-Da segment. The method is illustrated for experimental electrospray ionization FTICR ultrahigh-resolution mass spectra of a petroleum crude oil. Several thousand elemental compositions may be resolved visually in a single one-page two-dimensional display, and various compound families-class (NnOoSs), type (Z in C(c)H2(c+z)NnOoSs), and alkylation series-may be identified visually as well.

[Pulsatile rotary pumps with low hemolysis]

As is well known, a pulsatile flow is important in assisted-circulation but it is difficult to produce a pulsatile flow with rotary pump, because excessive hemolysis will be generated. The authors have found that the turbulent shear is the main factor for red cell damage and therefore the key point of pulsatile rotary pumps is to reduce the turbulence by producing a pulsatile flow. In the authors' pulsatile axial pump, the pulsatile flow is obtained by axial reciprocation of constant rotating impeller; the rotation and reciprocation of the impeller are driven separately by a DC motor and a pneumatic device. Though a physiological pulsatile flow could be achieved and turbulence would not increase remarkably because the impeller rotates constantly, a second driver except a DC motor is nevertheless necessary, thus the system will become complicated. In the authors' pulsatile radial pump, a pulsatile flow is achieved by changing the rotating speed of the impeller periodically. Turbulence is minimized by a special design of twisted vanes which enable the blood flow to change its direction rather than its dimension during periodic change of rotating speed. Hemolysis tests demonstrated that the index of hemolysis(IH) of the author's pulsatile radial pump is 0.020, with is slightly more than that of the author's nonpulsatile radial pump(IH = 0.015). Animal experiments indicated that the pulsatile radial pump can assist the circulation of calves for several months without harm to blood elements and organ functions of the recipients.

[Clinical implications of HCV quasispecies heterogeneity in patients with hepatitis C]

OBJECTIVE

To determine the heterogeneity of viral quasispecies and its clinical significance in patients with hepatitis C.

METHODS

Quasispecies in the sera from 76 patients infected with hepatitis C virus were detected using single stranded conformational polymorphism (SSCP) analysis of the HCV E2 hypervariable region 1 (HVR1).

RESULTS

HVR1 was amplified in 72 (94.7%) of the 76 patients. The average number of SSCP bands was 5.8, with a range from 2 to 11. The numbers of quasispecies in acute hepatitis, chronic hepatitis and liver cirrhosis and/or primary hepatocellular carcinoma were 3.1 +/- 1.2, 6.0 +/- 2.3 and 8.4 +/- 4.1, respectively. There was a statistically significant difference among them (P < 0.01). Patients with infection acquired by blood transfusion and i.v. drug use had greater number of quasispecies than those acquired by other transmission pathway (sporadic) (P < 0.05). Patients with genotype 1 a and 1 b infection had increased quasispecies compared with those infected with HCV type 2 and 3(P < 0.05). Increased quasispecies heterogeneity was significantly correlated with serum HCV RNA levels (P < 0.01).

CONCLUSIONS

SSCP is a simple, rapid and reliable method for the analysis of HCV viral quasispecies heterogeneity. Quasispecies heterogeneity plays an important role in HCV persistent infection and in the progress of hepatitis C. The duration of HCV infection, HCV genotype and HCV viremia are important determinants for the evolution of HCV quasispecies heterogeneity.

Infections caused by Flavimonas oryzihabitans

OBJECTIVE

To assess retrospectively the clinical characteristics and cell immune function of infections caused by Flavimonas oryzihabitans (F. oryzihabitans).

METHODS

We indentified 11 cases of F. oryzihabitans positive cultures from all microbial cultures collected in our hospital from November 1994 to December 1998. Relevant clinical information was collected, including demographic data, underlying disease, and clinical manifestations of the F. oryzihabitans infections. Minimal inhibitory concentrations (MICs) of 15 antimicrobial agents against the 11 F. oryzihabitans isolates were determined. Cell immune function tests were determined by flow cytometry including T lymphocyte subsets (CD3, CD4, CD8 and ratio CD4/CD8) and NK cells (CD16 + 56) from peripheral blood.

RESULTS

Six of these patients with infections caused by F. oryzihabitans were male, 5 were female and the mean age was 47.64 years (range, 5 to 69 years). All but 1 patients had severe underlying diseases. 9 (81.8%) of these patients developed infection while hospitalization and 2 (18.2%) before hospitalization (Cases 2 and 5). 8 (72.7%) of these patients manifested primary F. oryzihabitans bacteremia and one each (9.1%) had pleurisy, soft tissue infection and peritonitis. All these isolates were susceptible to amikacin, gentamicin and ciprofloxacin, but resistance to cefazolin, nitrofurantoin, penicillin and piperacillin. CD3, CD4, CD4/CD8 and CD16 + 56 value (mean +/- s) of these patients were significantly lower than normal values (P < 0.01). The mean time of body temperature fell < or = 37 degrees C after antibiotic treatment in these patients was 3.5 days (range, 1 to 6 days). All clinical symptom caused F. oryzihabitans after antibiotic treatment disappeared and all patients recovered.

CONCLUSIONS

Infections caused by F. oryzihabitans was very few clinically, and relative to underlying diseases and the presence of foreign material. Immune function abnormality was among mostly factor for the F. oryzihabitans infections.

Accuracy of aneroid sphygmomanometers in clinical usage: University of Michigan experience

BACKGROUND

Aneroid manometers are frequently used to measure blood pressure. Aneroid manometers have moving parts that are subject to fatigue. The accuracy duration of the aneroid devices, like most digital devices, is unstudied. It has been accepted that if the aneroid device does not rest at '0' it is inaccurate, but how often is the device inaccurate when it does rest at '0'?

METHODS

A Universal Biometer DPM-III measuring unit was used for all of the measurements at 10 University of Michigan Health System sites. A total of 136 aneroid manometers were tested. Two additional aneroid devices were not tested, as the needle did not start within '0'. Static pressure measurements were made at nine levels for all devices: 50, 80, 90, 100, 120, 150, 200 and 250mmHg.

RESULTS

The average difference of the nine pressure settings of the whole group was 0.2+/-0.31 (95% confidence interval 0.1-0.2) mmHg. The largest number of devices that were not calibrated within +/-3mmHg was seen at the 150mmHg setting with six (4.4%) of the devices failing. If an accuracy standard of +/-2mmHg was used, the largest number of devices failed at 250mmHg (22 devices, 16.2%). The largest number of devices that were inaccurate was manufactured 6 years prior to testing and was from two sites.

CONCLUSIONS

Aneroid devices were accurate. A yearly calibration programme should be performed and a +/-2mmHg standard should be used. Portable aneroid manometers may need to be more frequently calibrated due to the trauma associated with dropping.

[Determination of chloramphenicol in chloramphenicol and dexamethasone sodium phosphate ear drops by first derivative spectrometry]

Determination of chloramphenicol in the ear drops by first derivative spectrometry was studied. The detecting wavelength was 303.0 nm. The linear range was 0-65.2 micrograms.ml-1 (r = 0.9999). The average recovery was 99.84%, RSD = 0.37% (n = 8). The method is simple and accurate.

[A permanent implantable pulsatile impeller heart with a specially devised needle bearing]

The author's implantable pulsatile impeller pump can assist the circulation of the calves for several months. The termination of the experiments was related to wear of the mechanical bearing, which resulted in vibration of the rotor and pump failure. It seemed as if the experiments could have lasted indefinitely if the bearing had not failed. To solve the problem of bearing wear, a specially devised rolling bearing was investigated and applied to the impeller pump. Its service life is more than 10 years due to the wear-proof roller made of ultra-highmolecular weight polythene. This newly devised impeller heart promises to have long-term and permanent applications. Compared with the magnetic bearing, the rolling bearing has the advantages of simpler construction and control, no consumption of energy, and better reliability.

[A study on the pathogenesis of Streptococcus mitis exotoxin]

OBJECTIVE

To study the isolation, purification and pathogenesis of Streptococcus mitis pyrogenic exotoxin causing toxic shock syndrome.

METHODS

Streptococcus mitis isolated from patients' throat were shaking cultivated. After being centrifuged, the supernatant fluid of the culture was precipitated with 20%, 40%, 60%, 80% (NH(4))(2)SO(4) respectively and the fast protein liquid chromatography(FPLC) was used for the final step of purification. Rabbits receiving subcutaneous injection with respective purified proteins were monitored daily for fever. The ability of the purified proteins to enhance the susceptibility of the rabbits to lethal Escherichia coli endotoxin shock is recorded, when the endotoxin was injected intravenously 4 hours after administration of 10 microg Streptococcus mitis exotoxin.

RESULTS

Only the protein precipitated by 20% (NH(4))(2)SO(4) (molecular weight is 34,000) from culture supernatant fluid was pyrogenic for rabbits (average temperature increase near 1 degrees C), and it can also cause the proliferation of rabbit splenocytes (mitogenicity). All the animals receiving subcutaneous injection of exotoxin containing purified proteins precipitated with higher concentrations of (NH(4))(2)SO(4) died within 16 approximately 29 hours after intravenous injection of the Escherichia coli endotoxin, demonstrating the enhanced susceptibility of the animals to lethal endotoxin shock. The control rabbits displayed none of these effects.

CONCLUSION

Streptococcus mitis exotoxin is a novel streptococcal pyrogenic exotoxin.

Thyroid hormone coordinates respiratory control maturation and adenine nucleotide translocator expression in heart in vivo

BACKGROUND

The signal transduction mechanism linking mitochondrial ATP synthesis with cytosolic ATP utilization in heart changes during postnatal development in vivo. This maturational process occurs in parallel with accumulation of mitochondrial adenine nucleotide translocator (ANT), which provides a possible site for respiratory control. We postulated that thyroid hormone regulates these maturational processes.

METHODS AND RESULTS

We used (31)P MR spectroscopy to determine the relationship between myocardial high-energy phosphates, phosphocreatine, and ADP and oxygen consumption (MVO(2)) during epinephrine stimulation in 32- to 40-day-old lambs thyroidectomized after birth (THY) and age-matched controls. Steady-state protein and mRNA levels for ANT isoforms and beta-F(1)-ATPase were assessed from left ventricular tissues by Western and Northern blotting. With greater doses of epinephrine, THY attained lower peak MVO(2) than controls (P:<0.05). Controls maintained high-energy phosphate levels, unlike THY, which demonstrated significantly decreased phosphocreatine/ATP and increased cytosolic ADP despite lower peak MVO(2). No significant differences in beta-F(1)-ATPase protein or mRNA occurred between groups. However, ANT isoform mRNA levels were 2-fold greater and protein levels 4-fold greater in control hearts.

CONCLUSIONS

These data imply that the maturational shift away from ADP-mediated respiratory control is regulated by thyroid hormone in vivo. Specific thyroid-modulated increases in ANT mRNA and protein imply that this regulation occurs in part at a pretranslational level.

[Effect of various assist pumps on recovering the ventricular function]

With the authors' diaphragm pump and pulsatile as well as nonpulastile impeller pumps, and the clinically used Sarns Roller, both left ventricular assist and biventricular assist experiments were performed on mini pigs and calves. The results demonstrate that the pulsatile impeller pump is the best assist pump for recovering the heart function, because it maintains the pulsatility of aortic pressure by heart failure and thus increases the circulation volume, and it enlarges the diastolic pressure so as to increase the perfusion in coronary artery because it has no backflow.

Clinical, virological and histological implications of GB virus-C/hepatitis G virus infection in patients with chronic hepatitis C virus infection: a multicentre study based on 671 patients

To determine the prevalence, as well as the clinical, virological and histological implications of GB virus C/hepatitis G virus (GBC-C/HGV) infection in patients with chronic hepatitis C virus (HCV) infection, sera from 671 well-characterized patients with chronic HCV infection were tested for GBV-C/HGV RNA using a sensitive and specific reverse transcription 'nested' polymerase chain reaction (RT-nPCR). GBV-C/HGV RNA was detected in 65 of 671 (9. 7%) patients with chronic HCV infection. Importantly, GBV-C/HGV co-infection was not associated with any changes in indices of liver diseases, including serum alanine transaminase levels, Knodell score or histology activity index (HAI). In this cohort, GBV-C/HGV co-infection was weakly associated with a shorter mean estimated duration of HCV infection and a higher median HCV viraemia level. We conclude that GBV-C/HGV has minimal or no impact on liver disease activity in patients with chronic HCV infection. This data supports the notion that GBV-C/HGV may not be a hepatitis virus.