[The expression of MLC2-chymase fusion gene in cultured neonatal myocardial cells]

A series of MLC2-chymase fusion genes consisting of nested 5' deletion of the chymase promoter region were constructed and transfected into primary cultured neonatal Wistar rat myocardial cells according to the modified calcium phosphate precipitation method. Total RNA Dot-blot hybridization and analysis of densitometric scanning demonstrated that MLC2 promoter is enough to direct human heart chymase gene transcription in cultured neonatal rat myocardial cells. The highest level of expression was found with the MLC2-chymase construct containing 6 bp of the chymase promoter region. More sequence of the chymase promoter region between MLC2 promoter and the ATG of chymase gene resulted in a subsequent decrease in the expression of human heart chymase gene.

Theory of photothermal spectroscopy in an optically dense fluid

The theory of photothermal spectroscopy in an optically dense fluid is presented. The general case is considered in which the fluid may be flowing or stationary, and the excitation could be cw (modulated or unmodulated) or pulsed (arbitrary pulse length). All three detection schemes, deflection, phase shift, and lensing, are considered. This is the most complete theory of photothermal spectroscopy in fluids to date.

[The development of a fluid percussion device for brain injury of animals]

This paper discusses a fluid percussion device for brain injury. The injury is produced by striking the cork with a pendulum dropped from a known fall height to produce transient high pressure through a fluid transfer system. Experimental results show the device has the advantages of making a controllable, repeatable, and precise injury, and it can produce different levels of injury on different animals.

Epidemiology and prevention of pertussis

Pertussis continues to be a common cause of morbidity and mortality in unimmunized young children. In immunized populations, the disease remains endemic and epidemic. Reports of pertussis infection in older children and adults are increasing, and the data indicate that lifelong immunity from either pertussis immunization or childhood pertussis does not exist, which stresses the importance of continued booster immunization in this population. The less reactogenic acellular pertussis vaccines, which may provide protection equal to or even better than that provided by currently used whole-cell vaccines, seem to be suitable not only for primary immunization but also for boostering in all age groups. This review focuses on some recent developments in the epidemiology and prevention of pertussis infection.

Delivery of liposome-sequestered hydrophobic proteins to lysosomes of normal and Batten disease cells

We have developed a method to deliver hydrophobic proteins such as ATP synthase subunit c and ubiquitin to lysosomes of PMN (polymorphonucleocytes) and fibroblasts. ATP synthase subunit c is stored in the lysosomes of various tissues in late infantile and juvenile forms of neuronal ceriod lipofuscinosis, also called Batten disease (BD). Whether this protein storage is due to an abbreviation in protein or in the lysosomal hydrolases of BD is still not clear. We have sequestered this protein and ubiquitin in the lipid membrane of liposomes. The liposomes coated with autologous heat-aggregated IgG or apolipoprotein E when presented to the PMN and fibroblasts, respectively, accumulated in the lysosomes. Both normal and BD PMN degraded 125I-ubiquitin; the rate of degradation was, however, slower by Batten PMN. These studies indicate that a hydrophobic molecule such as subunit c can be delivered to PMN and fibroblasts, and the sequestered proteins are accessible to lysosomal hydrolases. Therefore, this technique can be used to study the metabolism of highly hydrophobic proteins by lysosomes, especially the biochemical mechanism(s) of subunit c storage in BD.

[Experimental and clinical study on the blood supply of the subdermal vascular network island flap]

A comparison study on the blood supply of the buttock subdermal vascular network island skin flap and the conventional buttock island flap was undertaken in pigs. The former was created by thinning the distal half of the conventional buttock island flap, preserving the subdermal vascular network. Evaluation was made by measurement of skin temperature, laser Doppler, fluorescence stain, ink perfusion, microangiography and transparent specimen technique. It was found that the blood supply of the subdermal vascular network island skin flap was much lower than that of the conventional island flap. The reason was thought to be the change in the blood supply after the conventional island flap was thinned. The subdermal vascular network island skin flap was composed of the axial pattern and the random pattern. Fifteen subdermal vascular network island skin flaps have been successfully transferred with vessel anastomosis in 15 patients. The average area of the thinned distal part was 49% of the flap, with the maximum of 60%.

Kinetics of G1/S and G2/M transition in X-irradiated ataxia-telangiectasia cells

Cell cycle transition defects of homozygous ataxia-telangiectasia (A-T) cells were studied by using a cell cycle flow calculation method, which evaluates the dynamics of cell cycle traverse. We compared five human lymphoblastoid cell lines (LCLs) from A-T homozygotes belonging to complementation group A (ARO, BRO, RJO) and group C (CSA, BMA) with three cell lines from healthy volunteers (KK-B2, MTB, HGL). The A-T cell lines ARO and BRO were derived from the same family. Cell growth and cell cycle traverse were followed for 72 h after X-irradiation with 1-6 Gy. LCLs from healthy volunteers immediately arrested in G1 in a dose-dependent pattern, while the A-T cells did not arrest in G1 until after 12 to 24 h. The time for the appearance of the G1 arrest of these cells was independent of complementation group. The delayed G1 arrest seen in the A-T cells paralleled a lack of induction of p53, as described by others. In respect to G2 arrest, A-T cells from complementation group C (CSA, BMA) arrested to the same extent as cells from healthy volunteers. On the other hand, the other LCLs from complementation group A arrested normally, while cells from ARO and BRO did not arrest in G2. The lack of G2 arrest in BRO cells was accompanied by unchanged cdc2p34 activity. In summary, a defective radiation-induced G1 arrest seems to be present in both complementation groups of A-T homozygotes, whereas a defective G2 arrest in not always observed. The defective G1 arrest seen in A-T cells may play an important role in tumor cell survival after exposure to therapeutic irradiation.

Impact of polymerase chain reaction on clinical pertussis research: Finnish and Swiss experiences

Since April 1993 in Finland and March 1994 in Switzerland, polymerase chain reaction (PCR) has been used routinely nationwide for the diagnosis of pertussis. Nasopharyngeal specimens from 3794 patients suspected of having pertussis and 1125 controls were tested. Finnish and Swiss assays found 23% and 36% of clinical specimens positive, respectively. PCR showed a higher incidence of pertussis infection among 1- to 6-year-old children in Switzerland than in Finland (P < .001). This difference may be due to the booster dose of vaccine given at 2 years of age in Finland but not in Switzerland. In Finland, PCR-confirmed asymptomatic cases were more common among children <7 years old than in older children (P < .001), whereas older children tended to have symptomatic infection. The use of PCR markedly improves the diagnosis of pertussis and opens new perspectives for epidemiologic and vaccine efficacy studies.

Analyses of reported family history of glaucoma: a preliminary investigation. The Barbados Eye Study Group

This study investigated the self-reported family history of open-angle glaucoma (OAG) among 4,314 black participants in the Barbados Eye Study (BES), which was based on a random sample of Barbados-born citizens between 40 and 84 years of age. Data collection included Humphrey perimetry, fundus photography, various ophthalmic and other measurements and a comprehensive interview, including family history. Results showed that participants with OAG and previous OAG treatment reported more family history; maternal history was reported twice as often as paternal history. In persons without previous OAG treatment, those with newly diagnosed OAG reported more sibling history (Odds Ratio = 4.5). The Statistical Analysis for Genetic Epidemiology (S.A.G.E.) system was used to test the transmission models for OAG in a subset of 1,048 families (5,806 individuals) with the most complete self-reported family information. The S.A.G.E. results are consistent with the existence of a major dominant allele for OAG. These results should be viewed as promising, but preliminary, since they are based on self-reported data. More definitive information is currently being collected by the Barbados Family Study of Open-angle Glaucoma.

Protective role of immunoglobulin G antibodies to filamentous hemagglutinin and pertactin of Bordetella pertussis in Bordetella parapertussis infection

An outbreak of parapertussis was studied prospectively in 38 first and second grade pupils of an elementary school. Eleven (29%) children were confirmed to be culture positive for Bordetella parapertussis. Serum samples were collected from 31 children for assay of antibodies to filamentous hemagglutinin (FHA), pertactin (PRN), and pertussis toxin of Bordetella pertussis. At the first sampling, ten children were found to have a cough and 21 were asymptomatic. Of the latter, 12 remained asymptomatic and eight developed cough within 11 to 53 days (mean +/- standard deviation, 31 +/- 12 days) after sampling. One child was identified as culture positive for Bordetella pertussis and, thus, not included in the analysis of Bordetella parapertussis infection. The mean levels of IgC antibodies to FHA and PRN were significantly higher in the 12 asymptomatic children than in the eight children who later developed cough or in 20 healthy control children of the same age (for FHA, p = 0.009 and < 0.001, respectively; for PRN, p = 0.002 and 0.002, respectively). These preliminary data suggest that Bordetella parapertussis infection is more prevalent than documented, and that children with high levels of IgG antibodies to FHA and PRN can remain asymptomatic.

High-frequency oscillations in membrane potentials of medullary inspiratory and expiratory neurons (including laryngeal motoneurons)

1. In midcollicular decerebrate, unanesthetized, paralyzed cats ventilated with a cycle-triggered pump system, the properties of high-frequency oscillations (HFOs, 50-100 Hz) in membrane potentials (MPs) of medullary inspiratory (I) and expiratory (E) cells were studied. Simultaneous recordings were taken from bilateral phrenic and recurrent laryngeal (RL) nerves and from cells in the intermediate ventral respiratory group (intVRG, 0-1 mm rostral to the obex) or the caudal ventral respiratory group (cVRG, 2-4 mm caudal to the obex). 2. Spectral coherence analyses were used to detect the presence of HFOs during I in I and E cell MPs. Cross-correlation histograms (CCHs) between the cell and phrenic signals were used to ascertain cell-nerve HFO phase relations and to identify cells as RL motoneurons. Of the 103 cells that had significant HFOs (cell-phrenic coherences > or = 0.1), measurable HFO peak lags in the CCH were seen in 53 cells: 1) RL cells (9 I cells and 7 E cells); and 2) other types of cell (8 intVRG I cells, 18 intVRG E cells, and 11 cVRG E cells). These cells had high HFO correlations; the cell-phrenic coherence range was 0.35-0.94, with a mean HFO frequency of 58 Hz. 3. The cell-phrenic HFO lag (in ms) was measured in the CCH as the lag of the primary peak (peak located nearest to 0 lag). The phase lag was defined as (lag of primary peak in ms)/(HFO period in ms). The phase lags differed markedly between two subsets of cells: 1) RL I cells had HFO depolarization peaks that lagged the phrenic HFO peaks (average cell-phrenic phase lag = -0.18); and 2) the non-RL cells, regardless of location (intVRG or cVRG) and type (I or E), had HFO depolarization peaks leading (preceding) the phrenic HFO peaks (average cell-phrenic phase lag = 0.28). In addition, the cVRG E cells had significantly shorter cell-phrenic phase lags than the intVRG E cells (0.23 vs. 0.31, respectively). 4. These lags can be compared with the (I unit)-phrenic phase lags (average approximately 0.3) found in earlier extracellular studies. 1) There is a transmission delay of about one half HFO cycle from excitatory I cells to RL I cells. 2) Because a depolarization peak in the MP of an E cell corresponds to the start of a hyperpolarizing wave, the excitatory bulbospinal pathways from I cells have transmission times comparable with those of the inhibitory intramedullary pathways from I cells to E cells. 5. These results indicate that study of HFO phase relations can furnish useful information on functional connectivity of medullary respiratory neurons during the I phase.

[The morphometric study of endometrium during long-term use of TCu220C IUD]

OBJECTIVE

To observe the pathological changes of endometrium in women using TCu220C intrauterine devices (IUD) for 5-12 years, and to judge its long term safety.

METHODS

A hundred women using TCu220C IUD for 5-12 years were randomly selected as IUD group. Samples of endometrium from the sites compressed by IUD and 1 cm apart were taken under hysteroscopy during proliferative phase. Another 100 women matched in age but not IUD users served as control group, and endometriums were taken by curettage. All the samples were studied for morphometry.

RESULTS

All pathological changes were localized in the areas of endometrium in direct contact with IUD but not the adjacent areas. Inflammatory reactions mainly lymphocytes infiltration were seen in all IUD samples with depth of 0.91-1.20 mm. Atrophy was seen in 25% of the cases using IUD for 5-10 years with an average area of 0.81 mm2, while in 71% of those using IUD for 10-12 years with an area of 1.50 mm2. Fibrosis was shown in 18% of the cases using IUD for 5-10 years with area of 1.87 mm2, and 100% in 10-12 years with area of 2.04 mm2. There was no hyper-proliferation and malignant changes in IUD group. Hemorrhage and necrosis existed in all cases using IUD for 10-12 years. In the IUD group all the cases showed asynchronization of endometrium.

CONCLUSION

It is safe for women using TCu220C IUD for 5-12 years. Since endometrial hemorrhage and necrosis were shown in women using IUD over 10 years, it is better to remove the IUD after 10 years if they have clinical symptoms.

Proton detection of choline and lactate in EMT6 tumors by spin-echo-enhanced selective multiple-quantum-coherence transfer

An extension of the Sel-MQC pulse sequence--SEE-SelMQC (spin-echo-enhanced selective multiple-quantum coherence transfer)--that completely suppresses lipid and water in tissues containing mobile lipid in a single scan and detects 1H resonances of multiple metabolites is described. As in the Sel-MQC lactate-editing experiments [Q. He et al., J Magn. Reson. B 106,203 (1995)], SEE-SelMQC acquires lactate from its ZQ --> DQ coherence-transfer pathway; in addition, the method recovers signal from other metabolites by selective generation of additional spin echoes using extra frequency-selective pulses and gradients. This method introduces no loss of lactate signal intensity beyond the 50% that is lost through the multiple-quantum coherence-transfer process. The spatial distributions of choline and lactate with a phantom and in vivo, in subcutaneously implanted murine EMT6 tumors, have been simultaneously mapped.

Secretory expression of a single-chain insulin precursor in yeast and its conversion into human insulin

A synthetic single-chain porcine insulin precursor (PIP) gene and an alpha-mating factor leader sequence (alpha MFL) gene obtained by the PCR method are inserted between the promoter and 3'-terminating sequence of the alcohol dehydrogenase gene ADH1 in plasmid pVT102-U to form plasmid pVT102-U/alpha MFL-PIP. The single-chain insulin precursor is expressed and secreted to the culture medium by Saccharomyces cerevisiae transformed by pVT102-U/alpha MFL-PIP. The precursor is purified and converted into human insulin by tryptic transpeptidation. The purified human insulin is fully active and can be crystallized. The overall yield of human insulin is 25 mg per liter of culture medium.

Characterization of a peptide antibody against a C-terminal part of human and mouse cytosolic thymidine kinase, which is a marker for cell proliferation

An affinity-purified anti-TK1 antibody (pAb1) raised against a synthetic peptide (amino acids K211PGEAVAARKLFAPQ225) corresponding to part of the C-terminus of human cytosolic thymidine kinase (TK1) was produced and characterized by enzyme-linked immunosorbent assay, Western immunoblotting and immunoprecipitation as well as by immunostaining of intact cells. pAb1 recognized a single 25 kDa TK1 polypeptide in extracts of human and rodent cells. The protein was localized to the cytoplasm, as studied by immunohistochemistry and there was no staining in G1/G0 cells or mutant cells lacking TK1 activity, while it was high in S-phase and G2 cells. When series of peptides were tested for antibody binding in which alanine was replacing each of the other amino acids one by one, lysines 211 and 220, proline 212 and glutamic acid 214 were found to be important for antibody reactivity. These results indicate that amino acids 211-214, which may form a turn region, constitute a major recognition site for pAb1, and this structure may also be involved in the cell cycle-dependent modification of TK1, pAb1 is a very useful tool for studies of the cell cycle regulation of TK1, and it may be used to identify and quantify rapidly proliferating cells such as tumor cells.

[An experimental study on compound anisodine III for softening scar of mouse skin after burn]

OBJECTIVE

The aim of this study was to investigate the mechanism of compound anisodine (CA) III which can rapidly soften the cicatrized tissue in clinical practice.

METHODS

2 mol/L NaOH was applied onto the back of 36 mice for one minute to induce deep grade skin burn injury. After 1 week local cicatrization occurred. The mice were randomly divided into 3 groups: 1 ml saline was used in group I as control, hyaluronidase 150 U dissolved in 1 ml 2% procaine was used in group II and 0.005% CA 0.1 ml in 2% procaine 1 ml with hyaluronidase 150 U was used in group III. Subcutaneous injection once every other day for two weeks was the method of drug administration in all the 3 groups and then all the rats were euthanized. The burned skin was sectioned for HE and modified Masson's stains.

RESULTS

Histopathology revealed there were epidermis proliferation, keratinization and fibrosis with disorderly arranged collagenous fibers invading into muscles and a large amount of inflammatory cells infiltrating the lesion in groups I and II. However, the skin was nearly normal in group III.

CONCLUSIONS

CA III can inhibit the epidermic and collagenous proliferation, improve the tissue blood supply and have antiinflammatory effect to prevent scar formation and promote epidermic repair in the skin.

Suspension culture of differentiated rat heart myocytes on non-adhesive surfaces

Cardiac myocytes isolated from adult rat ventricles have been maintained in a stable, differentiated state for prolonged periods by the use of suspension culture on hydrophobic tissue culture inserts or agarose-coated plates. The success of this procedure depends on the use of low-serum media to prevent myocyte-myocyte interaction and proliferation of any residual endothelial cells. Myocytes cultured in this manner retain many of their structural characteristics, suggesting that maintenance of their elongated irregular shape is not dependent on interaction with extracellular matrix. They also exclude trypan blue, can be vitally stained by the uptake and reduction of the tetrazolium dye MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide], synthesize myosin and when returned to adhesive surfaces are capable of attachment and attendant dedifferentiation. Stability of the myocytes in suspension permits their use in co-culture experiments; specifically, myocytes separated from endothelial cells by the hydrophobic membrane of the tissue culture insert stimulated proliferation of the latter cells, suggesting this to be a useful system for studying myocyte-endothelial cell interaction.

Incidence and progression of nuclear opacities in the Longitudinal Study of Cataract

PURPOSE

To estimate incidence and progression rates of nuclear opacities in the Longitudinal Study of Cataract, an epidemiologic study of the natural history of all types of lens opacities.

METHODS

The Lens Opacities Classification System III was used to assess longitudinal changes between baseline and follow-up lens photographs for the 764 Longitudinal Study of Cataract participants. Baseline data, collected until December 1988 as part of a case-control study, included color slit, retroillumination, and Scheimpflug photographs. The same data were collected by the longitudinal Study of Cataract at four subsequent visits at yearly intervals.

RESULTS

Among patients free of nuclear opacities at baseline, the incidence of new opacities was 6% after 2 years and 8% after 5 years of follow-up. The progression of pre-existing nuclear opacities was much higher. After 2 years, nuclear opacities had progressed in more than one third of the patients with pre-existing opacities; after 5 years, almost half had progressed. Older age was significantly related to higher incidence of new nuclear opacities, but not to progression of pre-existing opacities. Patients with other opacity types had higher nuclear incidence and progression rates.

CONCLUSIONS

In this clinic-based, older-patient population, new nuclear opacities developed in less than one tenth of the patients after 5 years of follow-up. In contrast, almost one half of the patients with pre-existing opacities had worsened after 5 years. These estimated rates can be used to plan intervention or other studies of nuclear changes in similar populations.