Crystal structure of the helicase domain from the replicative helicase-primase of bacteriophage T7

Helicases that unwind DNA at the replication fork are ring-shaped oligomeric enzymes that move along one strand of a DNA duplex and catalyze the displacement of the complementary strand in a reaction that is coupled to nucleotide hydrolysis. The helicase domain of the replicative helicase-primase protein from bacteriophage T7 crystallized as a helical filament that resembles the Escherichia coli RecA protein, an ATP-dependent DNA strand exchange factor. When viewed in projection along the helical axis of the crystals, six protomers of the T7 helicase domain resemble the hexameric rings seen in electron microscopic images of the intact T7 helicase-primase. Nucleotides bind at the interface between pairs of adjacent subunits where an arginine is near the gamma-phosphate of the nucleotide in trans. The bound nucleotide stabilizes the folded conformation of a DNA-binding motif located near the center of the ring. These and other observations suggest how conformational changes are coupled to DNA unwinding activity.

The linker region between the helicase and primase domains of the bacteriophage T7 gene 4 protein is critical for hexamer formation

The gene 4 protein of bacteriophage T7, a functional hexamer, comprises DNA helicase and primase activities. Both activities depend on the unidirectional movement of the protein along single-stranded DNA in a reaction coupled to the hydrolysis of dTTP. We have characterized dTTPase activity and hexamer formation for the full-length gene 4 protein (gp4) as well as for three carboxyl-terminal fragments starting at residues 219 (gp4-C219), 241 (gp4-C241), and 272 (gp4-C272). The region between residues 242 and 271, residing between the primase and helicase domains, is critical for oligomerization of the gene 4 protein. A functional TPase active site is dependent on oligomerization. During native gel electrophoresis, gp4, gp4-C219, and gp4-C241 migrate as oligomers, whereas gp4-C272 is monomeric. The steady-state k(cat) for dTTPase activity of gp4-C272 increases sharply with protein concentration, indicating that it forms oligomers only at high concentrations. gp4-C219 and gp4-C241 both form a stable complex with gp4, whereas gp4-C272 interacts only weakly with gp4. Measurements of surface plasmon resonance indicate that a monomer of T7 DNA polymerase binds to a dimer of gp4, gp4-C219, or gp4-C241 but to a monomer of gp4-C272. Like the homologous RecA and F(1)-ATPase proteins, the oligomerization domain of the gene 4 protein is adjacent to the amino terminus of the NTP-binding domain.

Contributors to violent behavior among elementary and middle school children

OBJECTIVE

To examine the relative contributions of exposure to violence, parental monitoring, and television-viewing habits to children's self-reported violent behaviors. The study hypothesized that: 1) children's exposure to violence would be associated positively with self-reported violent behaviors; 2) parental monitoring would be associated negatively with children's violent behaviors; and 3) the number of daily television-viewing hours and a preference for watching violent television shows would be associated positively with children's violent behaviors.

METHODS

The study used a survey design with an anonymous self-report questionnaire administered to students (grades 3-8) in 11 public schools. A total of 2245 students participated in the study, representing 80% of the students attending the participating schools during the survey. The subjects were from 7 to 15 years of age; 51% were male, 57% were white, 33% percent were black, and 5% were Hispanic.

RESULTS

Hierarchical multiple regression analysis of the total sample revealed that the combination of demographic variables, parental monitoring, television-viewing habits, and exposure to violence explained 45% of students' self-reported violent behaviors. Violence exposure and parental monitoring were the most influential contributors in explaining children's violent behaviors, accounting for 24% and 5% of the variance in violent behaviors, respectively.

CONCLUSIONS

All three hypotheses were supported. A significant association was demonstrated linking violence exposure, lack of parental monitoring, and television-viewing habits with children's self-reported violent behaviors within a diverse sample of elementary and middle school students. Our findings support the importance of parental monitoring of children and emphasize the need to identify and to provide services to youth who are exposed to violence.

[The method of wavelet transformation used for extracting the characteristic of the exercise ECG]

This article introduces the basic rationale of wavelet transformation and the algorithm of typical dyadic wavelet transformation with mother wavelet of the first derivative of a Gaussian smoothing function, this wavelet transformation is used to recognize the characteristic parameters of the exercise ECG, it is concluded that this method make significant effects on restricting base line drifting and lessening noisy component in the exercise ECG, it provides a new way to do further research on characteristic recognition of the exercise ECG in the exercise test.

A study of platelet organelles and membrane glycoprotein in patients with Binswanger's disease

OBJECTIVE

To discuss the possible role of platelets in Binswanger's disease by studying the changes of organelles and membrane glycoprotein in platelets.

METHODS

The organelles (dense bodies, alpha granules, and mitochondria) within platelets were measured with transmission electron microscopy in 25 patients with Binswanger's disease and matched controls, while alpha granule membrane glycoprotein CD62 and lysosomal integral membrane glycoprotein CD63 on platelet membrane were analyzed by flow cytometry.

RESULTS

The percentage of CD62-positive platelets was 3.6% +/- 2.1% and 5.7% +/- 2.4% in controls and in patients, respectively (P < 0.01). The percentage of CD63 expression platelets was 3.1% +/- 2.2% and 3.2% +/- 2.3% in controls and patients, respectively (P > 0.05). When compared with controls, platelets of patients contained fewer alpha granules (P < 0.01), and had no changes in dense bodies and mitochondria (P > 0.05). CD62 levels were different among patients with regarding to the degree of white matter low attenuation.

CONCLUSION

There is selective degranuation of platelets in patients with Binswanger's disease and the abnormalities of platelet secretion may play a role in the pathophysiology of this illness.

[Clinical study on jinmaitong composita on diabetic peripheral neuropathy]

OBJECTIVE

To verify the effect of Jinmaitong composita (JMTC) on red blood cell aldolase reductase activity (RBC-AR), RBC sorbitol (RBC-S) and nerve conductive velocity in diabetic peripheral neuropathy (DN).

METHODS

Sixty-six patients with DN were divided randomly into two groups, 33 patients in treated group treated with JMTC and 33 cases in the control group treated with Jinkui Shenqi (JKSQ), RBC-AR, RBC-S and nerve transmission speed were observed before and after three months treatment.

RESULTS

Level of RBC-AR, RBC-S apparently decreased and nerve conductive velocity increased (P < 0.05, P < 0.01) after TMTC treatment.

CONCLUSION

JMTC was able to improve the nerve conduction significantly with a lowering of RBC-AR and RBC-S and has good result in treating Diabetic peripheral neurophathy.

The behaviors of some heritability estimators in the complete absence of genetic factors

Heritability is an important concept in quantitative genetics and is widely used in human genetics. A high or even a moderate value of heritability estimate is usually taken as evidence for a genetic component for a quantitative trait. In this paper, the behaviors of some correlation-based heritability estimators are reexamined under the assumption of complete absence of any genetic factors. It turns out that when monozygotic (MZ) twins (or full sibs) are environmentally more similar than dizygotic twins (or half sibs), or when there is placement bias in MZ twins reared apart, those correlation-based heritability estimates can lead to nonnegligible or even high heritability values, even when genetic factors are completely absent. These alarming results suggest that extreme care should be exercised when using these heritability estimators.

Pleiotropic alterations in lipid metabolism in yeast sac1 mutants: relationship to "bypass Sec14p" and inositol auxotrophy

SacIp dysfunction results in bypass of the requirement for phosphatidylinositol transfer protein (Sec14p) function in yeast Golgi processes. This effect is accompanied by alterations in inositol phospholipid metabolism and inositol auxotrophy. Elucidation of how sac1 mutants effect "bypass Sec14p" will provide insights into Sec14p function in vivo. We now report that, in addition to a dramatic accumulation of phosphatidylinositol-4-phosphate, sac1 mutants also exhibit a specific acceleration of phosphatidylcholine biosynthesis via the CDP-choline pathway. This phosphatidylcholine metabolic phenotype is sensitive to the two physiological challenges that abolish bypass Sec14p in sac1 strains; i.e. phospholipase D inactivation and expression of bacterial diacylglycerol (DAG) kinase. Moreover, we demonstrate that accumulation of phosphatidylinositol-4-phosphate in sac1 mutants is insufficient to effect bypass Sec14p. These data support a model in which phospholipase D activity contributes to generation of DAG that, in turn, effects bypass Sec14p. A significant fate for this DAG is consumption by the CDP-choline pathway. Finally, we determine that CDP-choline pathway activity contributes to the inositol auxotrophy of sac1 strains in a novel manner that does not involve obvious defects in transcriptional expression of the INO1 gene.

Phosphorylation of the transcription factor forkhead family member FKHR by protein kinase B

Protein kinase B lies "downstream" of phosphatidylinositide (PtdIns) 3-kinase and is thought to mediate many of the intracellular actions of insulin and other growth factors. Here we show that FKHR, a human homologue of the DAF16 transcription factor in Caenorhabditis elegans, is rapidly phosphorylated by human protein kinase Balpha (PKBalpha) at Thr-24, Ser-256, and Ser-319 in vitro and at a much faster rate than BAD, which is thought to be a physiological substrate for PKB. The same three sites, which all lie in the canonical PKB consensus sequences (Arg-Xaa-Arg-Xaa-Xaa-(Ser/Thr)), became phosphorylated when FKHR was cotransfected with either PKB or PDK1 (an upstream activator of PKB). All three residues became phosphorylated when 293 cells were stimulated with insulin-like growth factor 1 (IGF-1). The IGF-1-induced phosphorylation was abolished by the PtdIns 3-kinase inhibitor wortmannin but not by PD 98059 (an inhibitor of the mitogen-activated protein kinase cascade) or by rapamycin. These results indicate that FKHR is a physiological substrate of PKB and that it may mediate some of the physiological effects of PKB on gene expression. DAF16 is known to be a component of a signaling pathway that has been partially dissected genetically and includes homologues of the insulin/IGF-1 receptor, PtdIns 3-kinase and PKB. The conservation of Thr-24, Ser-256, and Ser-319 and the sequences surrounding them in DAF16 therefore suggests that DAF16 is also a direct substrate for PKB in C. elegans.

Phosphorylation of serine 256 by protein kinase B disrupts transactivation by FKHR and mediates effects of insulin on insulin-like growth factor-binding protein-1 promoter activity through a conserved insulin response sequence

Insulin inhibits the expression of multiple genes in the liver containing an insulin response sequence (IRS) (CAAAA(C/T)AA), and we have reported that protein kinase B (PKB) mediates this effect of insulin. Genetic studies in Caenorhabditis elegans indicate that daf-16, a forkhead/winged-helix transcription factor, is a major target of the insulin receptor-PKB signaling pathway. FKHR, a human homologue of daf-16, contains three PKB sites and is expressed in the liver. Reporter gene studies in HepG2 hepatoma cells show that FKHR stimulates insulin-like growth factor-binding protein-1 promoter activity through an IRS, and introduction of IRSs confers this effect on a heterologous promoter. Insulin disrupts IRS-dependent transactivation by FKHR, and phosphorylation of Ser-256 by PKB is necessary and sufficient to mediate this effect. Antisense studies indicate that FKHR contributes to basal promoter function and is required to mediate effects of insulin and PKB on promoter activity via an IRS. To our knowledge, these results provide the first report that FKHR stimulates promoter activity through an IRS and that phosphorylation of FKHR by PKB mediates effects of insulin on gene expression. Signaling to FKHR-related forkhead proteins via PKB may provide an evolutionarily conserved mechanism by which insulin and related factors regulate gene expression.

SAC1-like domains of yeast SAC1, INP52, and INP53 and of human synaptojanin encode polyphosphoinositide phosphatases

The SAC1 gene product has been implicated in the regulation of actin cytoskeleton, secretion from the Golgi, and microsomal ATP transport; yet its function is unknown. Within SAC1 is an evolutionarily conserved 300-amino acid region, designated a SAC1-like domain, that is also present at the amino termini of the inositol polyphosphate 5-phosphatases, mammalian synaptojanin, and certain yeast INP5 gene products. Here we report that SAC1-like domains have intrinsic enzymatic activity that defines a new class of polyphosphoinositide phosphatase (PPIPase). Purified recombinant SAC1-like domains convert yeast lipids phosphatidylinositol (PI) 3-phosphate, PI 4-phosphate, and PI 3,5-bisphosphate to PI, whereas PI 4,5-bisphosphate is not a substrate. Yeast lacking Sac1p exhibit 10-, 2.5-, and 2-fold increases in the cellular levels of PI 4-phosphate, PI 3,5-bisphosphate, and PI 3-phosphate, respectively. The 5-phosphatase domains of synaptojanin, Inp52p, and Inp53p are also catalytic, thus representing the first examples of an inositol signaling protein with two distinct lipid phosphatase active sites within a single polypeptide chain. Together, our data provide a long sought mechanism as to how defects in Sac1p overcome certain actin mutants and bypass the requirement for yeast phosphatidylinositol/phosphatidylcholine transfer protein, Sec14p. We demonstrate that PPIPase activity is a key regulator of membrane trafficking and actin cytoskeleton organization and suggest signaling roles for phosphoinositides other than PI 4,5-bisphosphate in these processes. Additionally, the tethering of PPIPase and 5-phosphatase activities indicate a novel mechanism by which concerted phosphoinositide hydrolysis participates in membrane trafficking.

Evaluation of the clinical value of combination of 99mTc-MIBI myocardial SPECT and 18F-FDG PET in assessing myocardial viability

PURPOSE

To evaluate the value of 18F-FDG PET metabolic imaging and 99mTc-MIBI SPECT in the identification of myocardial viability in patients with previous myocardial infarction and left ventricular dysfunction.

METHODS

18F-FDG PET (made in China) and 99mTc-MIBI SPECT were performed in 60 patients (pts) (age 54+/-9 yr) with myocardial infarction before revascularization. Before and after revascularization, LVEF and wall motion were measured with echocardiography in 36 pts (Group A), and myocardial perfusion was evaluated in 24 pts (Group B).

RESULTS

According to the interpretation of perfusion and metabolic images, myocardial segments were classified into mismatch (MM): reduced myocardial perfusion and normal FDG uptake or match (M): reduced perfusion and FDG uptake. Out of 264 segments with hypoperfusion, 145 (54.9%) were MM, suggesting viable myocardium (G-A1 and G-B1), 119 (45.1%) were M, suggesting necrosis (G-A2 and G-B2). After revascularization, LVEF was increased in G-A1 (49+/-15% vs. 59+/-7%, p<0.05), and in G-B1 (50+/-8% vs. 59+/-12%, p<0.05), but was not improved in G-A2 and G-B2. LVEDD was decreased in G-A1 and G-B1 (p<0.05) and was unchanged in G-A2 and G-B2. The positive predictive value (PPV) of FDG PET for improvement of regional wall motion after revascularization was 88%, and the negative predictive value (NPV) was 72.6%. The PPV for improvement of perfusion was 84.1%, NPV was 85%, and accuracy was 84.4%.

CONCLUSION

18F-FDG imaging with Chinese PET has clinical value for assessing myocardial viability and identifying patients who will benefit from revascularization.

[Alterations of cell apoptosis and proliferation during transformation of a human bronchial epithelial cell line]

OBJECTIVE

To investigate the alterations of cell apoptosis and proliferation and its mechanism during transformation of a human bronchial epithelial cell line Y.

METHODS

Terminal deoxyribonucleotidyl transferase in situ labelling, BrdU incorporation, Western blotting and fluorescence in situ hybridization were used in the study.

RESULTS

During serial passages of the immortalized human bronchial epithelial cell line Y, some phenotypic alterations, such as higher colony forming efficiency in soft agar, resistance to serum-induced differentiation and low dependence on EGF were observed. The increase in cell proliferation and decrease in cisplatinum-induced apoptosis and the enhanced protein expression of Bcl-2, MDM2, PCNA and Cyclin D1 were found in the late passages of the cell line. The chromosomes of Y cells were diploid at the early passages, but became aneuploid in the late passages.

CONCLUSION

In addition to the increase in cell proliferation, inhibition of apoptosis might also contribute to the cytogenetic abnormality and the transformation of human bronchial epithelial cells.

Mutations in the zebrafish unmask shared regulatory pathways controlling the development of catecholaminergic neurons

The mechanism by which pluripotent progenitors give rise to distinct classes of mature neurons in vertebrates is not well understood. To address this issue we undertook a genetic screen for mutations which affect the commitment and differentiation of catecholaminergic (CA) [dopaminergic (DA), noradrenergic (NA), and adrenergic] neurons in the zebrafish, Danio rerio. The identified mutations constitute five complementation groups. motionless and foggy affect the number and differentiation state of hypothalamic DA, telencephalic DA, retinal DA, locus coeruleus (LC) NA, and sympathetic NA neurons. The too few mutation leads to a specific reduction in the number of hypothalamic DA neurons. no soul lacks arch-associated NA cells and has defects in pharyngeal arches, and soulless lacks both arch-associated and LC cell groups. Our analyses suggest that the genes defined by these mutations regulate different steps in the differentiation of multipotent CA progenitors. They further reveal an underlying universal mechanism for the control of CA cell fates, which involve combinatorial usage of regulatory genes.

[HLA-DQA1 genes involved in the genetic susceptibility to duodenal ulcer in Wuhan Hans]

OBJECTIVE

To study the genetic susceptibility of HLA-DQA1 alleles to duodenal ulcer in Chinese Hans from Wuhan and its nearby regions.

METHODS

Seventy patients with duodenal ulcer and fifty healthy controls were examined for HLA-DQA1 genotypes. HLA-DQA1 typing was carried out by digesting the locus specific polymerase chain reaction amplified products with alleles specific restriction enzymes (PCR-RFLP), Apal I, Basj I, Hph I, Fok I, Mbo II and Mnl I.

RESULTS

The allele frequency of DQA1 0301 in patients with duodenal ulcer (64.3%) was significantly higher than that in healthy controls (36%). In contrast, the allele frequency of DQA1 0102 in patients with duodenal ulcer (8.6%) was significantly lower than that in healthy controls (26%).

CONCLUSION

These findings suggest that DQA1 0301 is a susceptible gene for duodenal ulcer in Wuhan Hans while DQA1 0102 is its resistant gene, and there are immunogenetic differences in HLA-DQA1 locus between duodenal ulcer patients and healthy controls.

[A study on homozygous deletion, hypermethylation, mutation and expression of p16 gene in human breast cancer]

OBJECTIVE

To investigate the homozygous deletion (HZD), hypermethylation and mutation of p16 gene in human breast cancer and the relationship between the structural alterations of p16 gene and its expression.

METHODS

PCR and PCR-methylation assay with silver staining (PCR-MASS) were used to detect HZD and hypermethylation of p16 gene exon 1 in 60 fresh breast cancers and 24 normal breast tissues adjacent to cancer (as control tissues). PCR-SSCP and DNA sequencing were used for the analysis of p16 gene mutation. Moreover, p16 gene and mRNA were also detected in the 60 cases.

RESULTS

Of the 60 breast cancers, HZD was found in 7 cases, hypermethylation and mutation were found in 16 and 4 cases respectively, and the difference was statistically significant. The positive rates of p16 protein and mRNA in breast cancer were 28/60 and 39/60 respectively.

CONCLUSION

The results demonstrate that several kinds of p16 gene structural changes exist in breast cancer. The structural changes of p16 gene cause abnormal p16 expression, the main mechanisms are hypermethylation, while HZD or mutation are the secondary causes. Abnormal expression of p16 gene then becomes involved in the development and metastasis of breast cancer.

[Rapid bioluminescence method for pathogen detection of nephropyelitis patient]

ATP is a kind of necessary metabolites in the living cells. We detected ATP contents in 222 bacteriuria or the urine germ by bioluminescence method. The results showed that the patient had been infected when the mean value was > 130.9 +/- 11.38 and had not when the mean value was < 32.9 +/- 2.26. The results were the same with the Gram Stain, L-form bacteriuria culture and the common bacteriuria culture. The mean values of positive specimens are higher than that of the negative specimens by the bioluminescence. Thus, it is indicated that the bioluminescence method has high sensitivity. This method can be used to detect L-form bacteriuria in the urine germ quickly and is important for early diagnosis by the doctors.

Maternal psychological distress and parenting stress after the birth of a very low-birth-weight infant

CONTEXT

Few studies document how parents adapt to the experience of a very low-birth-weight (VLBW; <1500 g) birth despite societal concerns about the ethics and justification of intensive care for these infants.

OBJECTIVE

To determine the degree and type of stress experienced over time by mothers whose infants vary in degree of prematurity and medical and developmental risk.

DESIGN

Longitudinal prospective follow-up study of a cohort of mothers of high- and low-risk VLBW and term infants from birth to 3 years.

SETTING

All level III neonatal intensive care units from a large midwestern metropolitan region.

PARTICIPANTS

Mothers and infants prospectively and consecutively enrolled in a longitudinal study between 1989 and 1991. High-risk VLBW infants were diagnosed as having bronchopulmonary dysplasia, and comparison groups were low-risk VLBW infants without bronchopulmonary dysplasia and term infants (>36 weeks, >2500 g).

MAIN OUTCOME MEASURES

Standardized, normative self-report measures of maternal psychological distress, parenting stress, family impact, and life stressors.

RESULTS

Mothers of VLBW infants (high risk, n = 122; low risk, n = 84) had more psychological distress than mothers of term infants (n=123) at 1 month (13% vs 1%; P = .003). At 2 years, mothers of low-risk VLBW infants did not differ from term mothers, while mothers of high-risk infants continued to report psychological distress. By 3 years, mothers of high-risk VLBW children did not differ from mothers of term children in distress symptoms, while parenting stress remained greater. Severity of maternal depression was related to lower child developmental outcomes in both VLBW groups.

CONCLUSIONS

The impact of VLBW birth varies with child medical risk status, age, and developmental outcome. Follow-up programs should incorporate psychological screening and support services for mothers of VLBW infants in the immediate postnatal period, with monitoring of mothers of high-risk VLBW infants.

[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.

[Measurement of tibia bone content and fracture threshold by quantitative ultrasonography in normal and fractured women in Taiyuan]

OBJECTIVE

To establish the reference range of tibia bone content in normal female of Taiyuan area and to explore the diagnostic criterion for osteoporotic fracture threshold by quantitative ultrasonography (QUS).

METHODS

The tibia bone contents (QUS value) of 1,681 normal women (aged 7-92 years) and 63 fractured women (aged 46-91) in Taiyuan were measured by QUS.

RESULTS

The QUS value increased with age in normal women before age 30, and peaked at age 30-40, then decreased and reached significance after age 50. There was a negative correlation between QUS value and duration after menopause (P < 0.01). Taken the mean QUS value of normal female aged 20-40 years minus 2.5 s (3,667 m/s) as a cutoff threshold, 93.7% of the 63 fractured women had their QUS value below this threshold.

CONCLUSION

It is suggested that the above cutoff QUS value may be considered as the risk threshold of osteoporotic fracture in women.

[Gas-sensing transmittivity spectrum of two-dimension SnO2: TiO2 compound film in ammonia vapor]

In this paper, we studied the gas-sensing transmittivity spectrum of the two-dimension SnO2: TiO2 compound film in ammonia vapor. It was observed that when the gas concentration was relatively low the transmittivity decreased as the gas concentration decreased, and when the gas concentration was relatively high, the transmittivity increased as the gas concentration increased. We considered the effect of the wet vapor, and explained this phenomenon.

Prevalence of male pattern hair loss in 18-49 year old men

BACKGROUND

Previous studies investigating the prevalence of male pattern hair loss (MPHL) typically used biased samples of men recruited from clinical populations which may limit generalizability of findings to broader populations.

OBJECTIVE

To obtain an updated and improved estimate of the occurrence of MPHL in healthy men residing in the community.

METHODS

Community-based sample of healthy men aged 18-49 years participated in a study investigating the effects of MPHL. Participants completed a brief questionnaire self reporting degree of hair loss, general health-related quality of life (HRQL) and hair-loss-specific measures. A trained observer also rated each participant using standardized classification for MPHL.

RESULTS

The proportion of men with moderate to extensive hair loss (type III or greater) was 42%. The proportion of men with moderate to extensive hair loss increased with increasing age, ranging from 16% for men 18-29 years of age to 53% of men 40-49. Twelve percent of the men were classified as having predominantly frontal baldness (type A variants).

CONCLUSIONS

MPHL, especially frontal baldness, may be more common than previously reported.

[Synthesis and application of novel acrylic resin as enteric coating]

The pH sensitive two- and three-component acrylic resins were synthesized by radical solution copolymerization of methyl methacrylate (MMA), methacrylic acid (MAA) and/or butyl acrylate (BA) and their acid values were measured by acid-base titration. The dissolution of naproxen pellets coated with the synthesized resins in dissolution medium of different pH value was studied. The results show that the acrylic resin with different acid value can be prepared by adjusting the monomer ratios (MMA:MAA or MMA:MAA:BA). The smaller the acid value of the resin is, the higher pH sensitive value it has. The release of naproxen from pellets coated with these resins is greatly influenced by the pH value of the dissolution medium and the pH sensitive value of the coating resin. The three-component resins are plastic and can be used as coating material without adding plastisizers.

Functional assignment by Chimera construction of the domain affecting heterotropic activation of deoxyadenosine kinase from Lactobacillus acidophilus R-26

The heterodimeric subunits of deoxyadenosine kinase (dAK)-deoxyguanosine kinase (dGK) from Lactobacillus acidophilus R-26 exhibit contrasting conformations manifested in the nearly unidirectional heterotropic activation of dAK when dGK binds deoxyguanosine. This is mediated, in part, by the conserved Ras switch I-like sequence (residues 153-161) [Guo et al. (1997) J. Biol. Chem. 272, 6890-6897]. In an attempt to identify domains differentiating the specificities of dAK and dGK, we constructed several chimeras splicing heterodimeric dAK within this region. In Chimera-III, dAK residues 120-170 were replaced by the homologous section of dGK. dAK activity was elevated 40%, but although it retained its original specificity and Km values, it could no longer be activated by deoxyguanosine. Moreover, both the activated dAK and the "dAK" of Chimera-III exhibited (i) an increased Ks for the leading substrate ATP-Mg2+, suggesting the formation of intermediate enzyme species along their respective kinetic pathways, and (ii) broadened and lower pH optima for the dAK activities. These observations further indicate the importance of dAK residues 120-170, including the Ras-like segment, in catalysis and heterotropic activation. The other conformational properties of dAK (e.g. self-inactivity and MgATP being the leading substrate) were unaltered by this substitution, thus localizing the responsible domains even further upstream.

Role of endogenous interferon-gamma on the enhancement of splenic NK cell activity by electroacupuncture stimulation in mice

Successive electro-acupuncture (EA) stimulation applied to bilateral anterior tibial muscles, where Zusanli (ST36) acupoints are located, once a day (30 min) for 3 successive days significantly enhanced splenic natural killer (NK) cell activity in BALB/c mice. The percentage of splenic NK cells, as measured by flow cytometry, was not affected in these mice. Interferon (IFN)-gamma level in splenic aqueous extract, prepared from the ST36 acupoint-stimulated mice, was significantly higher than that of the controls. In vivo treatment with neutralizing monoclonal antibody against mouse IFN-gamma completely abrogated the increase in splenic NK cell activity induced by ST36 acupoint stimulation. The same stimulation also significantly increased the concentration of splenic beta-endorphin, which coincided with the significant increase in splenic IFN-gamma production. Pre-administration of 10 mg/kg naloxone before initiation of EA stimulation every day reduced the enhancements of NK cell activity and IFN-gamma level. These observations strongly suggest that endogenous IFN-gamma mediates the up-regulation of NK cell activity by EA stimulation at the ST36 acupoints. Furthermore, endogenous beta-endorphin secreted by EA stimulation also plays an important role in the up-regulation of NK cell function, which may be realized through regulating IFN-gamma production.

[Selection of key biological components (KBC) for Controlled Ecological Life Support System (CELSS)]

Biological components are key parts in Controlled Ecological Life Support System (CELSS), the future experimental success will depend to a large extent on the suitability of selected KBCs. For this purpose, 15 KBCs including 4 higher plants(vegetables), 5 microorganisms, 5 microalgae and 1 lower plant were selected from lots of biological species for CELSS. These results laid a solid foundation for our studies of CELSS.

[Isolation and identification of active constituent of Toddalia asiatica in cardiovascular system]

The ethereal extract from the crude ethanolic extract of Toddalia asiatica was chromatographed on silica gel and tested on biological activity. A crystalline was obtained and confirmed as an active constituent in cardiovascular system. The active constituent was identified as isopimpinellin on the basis of chemical method and spectral analysis.

[Development of new ambulatory monitor for multi-channel gastroesophageal pH combining with cardiogram]

A new ambulatory monitor for multi-channel gastroesophageal pH combining with cardiogram is introduced in this paper. Key techniques of the monitor, design of hardware and software, clinical significance are described. Clinical application shows that the monitor advantages the diagnoses of functional diseases of upper digestive tract, especially is significant to distinguish the chest pain of cardiac origin and esophageal origin.

[Effects of Chinese herbs xianzhen tablet on the deformability of erythrocyte in non-insulin-dependent diabetes mellitus patients with deficiency of both qi and yin and deficiency of kidney with blood stasis]

OBJECTIVE

To explore the effects of Xianzhen Tablet (XZT) on the hemorheology of type 2 diabetes (NIDDM) on the basis of previous studies in XZT, that have indicated its ability to deplete fasting blood glucose, to reduce the injury of free radical to the body, to improve the Na(+)-K(+)-ATPase in the erythrocyte membrane of NIDDM.

METHODS

Erythrocyte deformability and aggregation were studied with Ektacytometer in a total of 60 type 2 diabetes who were randomly divided into two groups. One was ZXT treated group, another was placebo group.

RESULTS

(1) The erythrocyte deformability of type 2 diabetes was lower than that in normal subjects (P < 0.001), but the erythrocyte aggregation increased abnormally than that of health people (P < 0.001). The correlation test indicated there were negative correlation with plasma fibronogen and positive correlation with blood cholesterol (P < 0.05). (2) The erythrocyte deformability in the ZXT treated group with 30 patients improved after 8 weeks treatment (P < 0.01), with the decreased fasting blood glucose and plasma fibrinogen (P < 0.05). Compared with placebo group, there was significant statistical difference (P < 0.01).

CONCLUSIONS

XZT could improve the erythrocyte deformability in the type 2 diabetes.

[Gene expression in vivo mediated by adenoviral vector after direct gene transfer into anastomotic rat carotid arteries]

OBJECTIVE

To observe the efficiency and time course of gene expression in vivo mediated by adenoviral vector after direct gene transfer into anastomotic rat carotid arteries.

METHODS

After being soaked in high concentration of glucose solution containing Adv5-CMV (control group) or Adv5-CMV/LacZ (treatment group) for 30 minutes, soluble stents were inserted into the lumina of cut rat carotid arteries and end-to-end anastomoses were performed. On the 2nd, 7th, 14th, 28th, 60th and 90th day after surgery, the anastomotic carotid arteries of the two groups were explanted. All samples were analyzed for the presence of beta-galactosidase activity and histochemical staining.

RESULTS

beta-galactosidase activity was not detected in the carotid arteries of the control group. Microscopic examination of sections from vessels of the control group revealed no X-gal staining. The treatment group revealed bluestaining in all anastomotic arteries and in all layers of the arterial wall explanted including the intima, media, and adventitia on the 7th, 14th day postoperatively.

CONCLUSIONS

Adenoviral vector could make foreign effectively transfer into rat carotid arteries in vivo. Mediated by adenoviral vector after direct gene transfer into anastomotic rat carotid arteries, the high level of gene expression only persisted about one month.

[Experimental study of the architecture of skin following tension traction and wound closure]

The experiment performed on domestic pig, was designed to investigate the architecture of the stretching skin and the effect of tension traction on the wound closure. An 7 cm x 3.5 cm was drawn at a standard position. Drawing horizontal and vertical lines on the traction area, points of 1 cm apart were tattooed on the lines. A traction force measuring device was used to draw the wound edges together. Measurements of the distances between the points were made. An 7 cm x 10 cm wound was made on identical sites of each hind leg. In the experiment the traction tension was applied on the edges of wound immediately after the wound debridement. The results showed the stretched distance in the two areas was 5-7 times the width of the wound. The gain of skin from traction was 61-89 percent in the width of the wound. The wounds from traction five days could be closed 5 days after traction. It was concluded that the skin which could be used for traction was abundant. Wound closure with the skin traction technique had many advantages, such as rapid decreasing the size of wound and early closing of wound.

[Clinical epidemiological research of antigastroesophageal reflux after cardiac plasty by anastomosis of esophageal mucosa and gastric wall]

A new operative method was designed for preventing gastroesophageal reflux after esophageal and cardiac cancer operation. From April, 1994 to December, 1995, sixty-one patients after resection of esophageal and cardiac cancer were randomly divided into two groups: experimental group with 34 patients and control group with the others. All patients were observed, monitored and followed up. It was found that no case in the experimental group showed symptoms of gastroesophageal reflux or marked reflux by esophagoscopy and barium meal examination. 10 patients (37%) in the control group had the symptoms of heartburn and regurgitation and inflammation and obvious gastroesphageal reflux were observed under esophagoscopy and barium meal examination. The pH values of anastomotic ostium were 7.0249 +/- 0.9996 and 4.6667 +/- 2.4573 in the experimental and control groups, respectively. Significant difference (P < 0.01) was observed between two groups with t test. The results showed that the advancement of operative method plays a key rolein prevention of gastroesophageal reflux.

[In situ hybrid detection of p16 mRNA in primary breast carcinoma: its clinicopathologic significance]

OBJECTIVE

To investigate the expression of p16 mRNA in primary breast carcinoma and its clinicopathological significance.

METHODS

In vitro transcriptional RNA probe labeled with biotin and in situ hybridization method were used in this study to detect p16 mRNA in the paraffin embedded tissue of human primary breast carcinoma from 120 cases.

RESULTS

85 breast carcinomas showed expression of p16 mRNA with a positive rate of 70.8%. The p16 mRNA expression was not obviously correlated with patient age, tumor size, estrogen and progesterone receptor status (P > 0.05), but the positive rate of 54.4% for the lymph node metastasis group was significantly lower than 85.7% of the non-metastasis group (P < 0.001). Moreover, the positive rate of 58.3% for the poor differentiate invasive duct carcinoma was also lower than that 89.7% for the well differentiated (P < 0.05). The patients after operation were followed up. The mortality of 25% (21/85) in the p16 mRNA positive group was significantly lower than that of the negative group 57% (20/35) (P < 0.01).

CONCLUSION

Abnormal expression of p16 mRNA may play an important role in the development of human breast carcinoma.

Endothelial cell loss after photorefractive keratectomy for myopia

PURPOSE

To study the long-term effect of 193 nm excimer laser photorefractive keratectomy (PRK) on the human corneal endothelial cell density.

SUBJECTS AND METHODS

One hundred and twenty-four eyes from 71 patients underwent photorefractive keratectomy for myopia or myopic-astigmatism. Endothelial cell density was examined a short time before the operation and on an average of 50 months after the operation using a contact specular microscope. A subgroup of 32 eyes from 20 patients treated only once was examined preoperatively and 7 and 52 months postoperatively. The endothelial cell densities were corrected for the changing magnification of the contact specular microscope with changing central corneal thickness and for the expected physiological cell loss with time.

RESULTS

The average endothelial cell density was preoperatively 3098+/-283 cells/mm2 (mean+/-SD) and postoperatively 3048+/-294 cells/mm2 corresponding to a change of -50+/-157 cells/mm2. This was statistically significantly different from zero in a paired t-test (n=124, t=3.58, 2p<0.001). The average changes in endothelial cell density for the subgroup were -34+/-159 cells/mm2 for the postoperative time interval 0-7 months and -20+/-188 cells/mm2 for the postoperative time interval 7-52 months. These results were not statistically significantly different from zero in a paired t-test (n=32, t=1.21 and t=0.60, 2p>0.05). A statistically significant negative correlation between preoperative cell density and the change in cell density was found (n=124, r=-0.21, 2p<0.05).

CONCLUSION

This study suggests a potentially harmful effect of PRK on the human corneal endothelium. It appears that most cells are lost during ablation or within the first period of time after PRK.

[A micro transducer for dynamic multi-location pH monitoring in upper digestive tract]

A new transducer catheter used for dynamic multi-location pH monitoring in upper digestive tract has been developed. On the catheter several antimony electrodes and an Ag-Agcl electrode are integreted. An animal experiment compared the results of gastric aspiration and dynamic recording and demonstrated the reliability of this transducer. Clinical application has shown that this technology contributes greatly to the research on digestive physiology and to the diagnosis of functional diseases such as non-cardiac chest pain.

Triterpenoid saponins from Quillaja saponaria

Three new saponins were isolated from a commercial bark extract of Quillaja saponaria Molina. These compounds were also obtained as degradation products from larger saponins in this extract when treated with strong alkali. The compounds were characterized, using mainly NMR spectroscopy, mass spectrometry and chemical methods, as quillaic acid 3-O-¿beta-D-galactopyranosyl-(1-->2)-beta-D-glucopyranosiduronic acid¿, 3-O-¿alpha-L-rhamnopyranosyl-(1-->3)-[beta-D-galactopyranosyl-(1-->2)] -beta-D-glucopyranosiduronic acid¿ and 3-O-¿beta-D-xylopyranosyl-(1-->3)-[beta-D-galactopyranosyl -(1-->2)]-beta-D-glucopyranosiduronic acid¿, respectively.

[Nitric oxide in the treatment of COPD-induced chronic cor pulmonale: therapeutic effect and mechanism]

OBJECTIVE

To study the hemodynamic and oxygen-dynamic effects and the mechanism of nitric oxide (NO) inhalation therapy in COPD-induced chronic cor pulmonale at acute exacerbation period.

METHOD

Right heart catheterization was performed in 11 cases of chronic cor pulmonale. The hemodynamic parameters and plasma endothelium-I(ET-I) level were examined and recorded before and after inhalation of 40 ppm NO for 20 minutes. The plasma level of NO and lipid peroxide Ca(2+)-Mg(2+)-ATPase(calcium pump) and Na(+)-K(+)-ATPase (natrium pump) activities of RBC membrane in 30 cases of chronic cor pulmonale and 30 healthy controls were determined synchronously.

RESULTS

After NO therapy, the average pulmonary pressure (PAPM) and pulmonary vascular resistance index (PVRI) were lowered by 16.6% and 25.9% respectively (P < 0.05). Intrapulmonary shunt was lowered by 16.3% (P < 0.05). ET-I also lowered and showed a positive correlation with PAPM (r = 0.59, P < 0.05). The activities of calcium and natrium pump were lowered when NO level declined, showing a positive correlation with NO concentration and negative correlation with lipid peroxides.

CONCLUSION

No inhalation therapy exerted favorable hemodynamic and oxygen-dynamic effects on COPD-induced chronic cor pulmonale in its exacerbation period. Suppression of ET-I release might be one of the important factors for pulmonary vessel relaxation. Dysfunction of calcium and natrium pump activities in the acute exacerbation period of chronic cor pulmonale were closely related to NO level.

[Comparison studies on pharmacodynamics of three kind of Carapax trionycis]

Three kinds of Carapax Trionycis were used in rat to prevent and treat syndrom-complex of dificiency of Yin. Compareing the improvement of symptoms of dificiency of Yin, it was found that all of them actted effectively in various degrees. The effect of ZhongHua Carapax Trionycis (ZHCT) was similar to those of Shan Rui Carapax Trionycis (SRCT), but the efficacy of Green Carapax Trionycis (GCT) was inferior to those of ZHCT and SRCT. All kinds of C. Trionycis could increase the function of responding to iriation in mice with deficiency of Yin. The intensity of ZHCT was similar to that of GCT, and superior to that of SRCT. They all could enhance phagocytic function of eticuloedothelial system obviously, promot the development of thymus in different degrees with no efect on spleen in young mice. The efficacy of increasing the immune function of ZHCT and GCT were more potent than that of SRCT. ZHCT and GCT significantly decreased the activity of SGPT in mice poisoned by CC14. ZHCT and GCT protected liver better than SRCT did.

Protein kinase B/Akt mediates effects of insulin on hepatic insulin-like growth factor-binding protein-1 gene expression through a conserved insulin response sequence

Insulin regulates the expression of multiple hepatic genes through a conserved insulin response sequence (IRS) (CAAAAC/TAA) by an as yet undetermined mechanism. Protein kinase B/Akt (PKB/Akt), a member of the PKA/PKC serine/threonine kinase family, functions downstream from phosphatidylinositol 3'-kinase (PI3K) in mediating effects of insulin on glucose transport and glycogen synthesis. We asked whether PKB/Akt mediates sequence-specific effects of insulin on hepatic gene expression using the model of the insulin-like growth factor binding protein-1 (IGFBP-1) promoter. Insulin lowers IGFBP-1 mRNA levels, inhibits IGFBP-1 promoter activity, and activates PKB/Akt in HepG2 hepatoma cells through a PI3K-dependent, rapamycin-insensitive mechanism. Constitutively active PI3K and PKB/Akt are each sufficient to mediate effects of insulin on the IGFBP-1 promoter in a nonadditive fashion. Dominant negative K179 PKB/Akt disrupts the ability of insulin and PI3K to activate PKB/Akt and to inhibit promoter activity. The IGFBP-1 promoter contains two IRSs each of which is sufficient to mediate sequence-specific effects of insulin, PI3K, and PKB/Akt on promoter activity. Highly related IRSs from the phosphoenolpyruvate carboxykinase and apolipoprotein CIII genes also are effective in this setting. These results indicate that PKB/Akt functions downstream from PI3K in mediating sequence-specific effects of insulin on the expression of IGFBP-1 and perhaps multiple hepatic genes through a conserved IRS.

[RBC-CR1 genotype polymorphism and RBC immune function in childhood ITP]

OBJECTIVE

To investigate the RBC immune functions in childhood idiopathic thrombocytopenic purpura (ITP).

METHODS

RBC-CR1 polymorphism genotype, RBC immune function and its regulator function were detected in 22 ITP, 30 allergic purpura (AP) and 50 normal children by PCR and Guo Feng's method.

RESULTS

1. There were 18 cases of high expression (82%) and 4 of medium expression (18%) of RBC-CR1 genotypes in the ITP cases. The rate of the medium expression genotype was significantly higher in ITP than that in AP and normal children (P < 0.01). 2. The rates of RBC-C3bRR and RBC-C3bRFER were much lower (P < 0.01), and the rates of RBC-ICR and RBC-C3bRFIR were significantly higher in ITP than those in normal children (P < 0.01). 3. RBC-CR1 genotypes in ITP were correlated negatively with RBC-C3bRR and RBC-C3bRFER (P < 0.05), but positively with RBC-ICR and RBC-C3bRFIR (P < 0.05).

CONCLUSION

RBC immune participated in the pathogenesis of ITP.

[Studies on the morphology of fruit-body developing of Polyporus umbellatus]

OBJECTIVE

Studying the fruit-body development of polyporus umbellatus to reveal the life-cycle of this medicinal fungus.

METHODS

Parts of materials treated by paraffin section, and examined under a light microscope; parts of materials by ultrathin section and observation under transmission electron microscope (TEM).

RESULTS

The fruit-body consists of trimitic hyphae, including generative hyphae, skeletal hyphae and binding hyphae. Generative hyphae are characterized by thin walls, dense cytoplasmic contents. Skeletal hyphae are unbranched, thick-walled, and of a narrow lumen. Binding hyphae are much-branched, tending to weave themselves among the other hyphase of flesh. The morphology of basidiospore development was also discussed in this paper.

CONCLUSIONS

The trimitic hyphae are the main component parts in the different developing stages of fruit-body of polyporus umbellatus.

Comparison of biodegradable and metallic tension-band fixation for patella fractures. 38 patients followed for 2 years

We compared the outcome of patella fractures fixed by biodegradable tension-band (B) with self-reinforced polyglycolide or self-reinforced poly-L-lactide plugs and polyester ligaments or by metallic tension-band (M) with Kirschner wires and metallic cerclage wire in a randomized study. 38 fractures (18 with B and 20 with M) were treated. The follow-up time was 24 (14-32) months. The fractures healed in all patients after a medium of 8 weeks. In the B group, the clinical outcome was good in 13, fair in 4, and poor in 1 patient. In the M group, the corresponding figures were 15, 3 and 2. There were no clinical or radiographic differences between the two methods. Patella fractures can be treated, successfully using biodegradable tension-band fixation with no need for a second operation to remove the implants after bone union.

[The role of pro-UK gene in protecting vein graft from thrombosis]

OBJECTIVE

To study the role of Pro-UK gene in protecting vein graft from thrombosis.

METHODS

42 Wister rats underwent implantation of reversed autologous jugular vein interposition grafts in the common carotid artery. Jugular veins were exercised and distended with solution containing either Adv5-CMV(control group) or Adv5-CMV/Pro-UK(treatment group) for 30 minutes, then the jugular veins were reversed and interposed into the divided carotid arteries. Proximal and distal anastomoses were performed in an end to end fashion with interrupted 11-0 polypropylene sutures. 14 days after surgery, the vein graft of two groups were explanted to examine the presence of Pro-UK gene expression. The amount of 51 Cr-labeled platelet of the two groups was counted 24 hours postoperatively. Segment of grafts of both group was explanted 14 days after surgery for histologic analysis.

RESULTS

Pro-UK activity was not detected in the vein graft of the control group. In the treatment group, the amount of Pro-UK gene express was 308 IU/g tissue. The amount of 51Cr-labeled platelet of the two groups was (123.7 +/- 19.4) x 10(6)/gdrywt. (34.4 +/- 5.3) x 10(6)/gdrywt. The amount of the control group was prominent over the treatment group(P < 0.01). On the 14th day after surgery, the thrombosis rate and occlusion rate of the vein graft in the control group were 30%, 10% respectively. In the treatment group, all vein grafts were patent and free of thrombosis.

CONCLUSIONS

Mediated by adenoviral vector after direct gene transfer into vein graft, Pro-UK gene expression could protect graft from thrombosis. Therefore, this method could effectively enhance venous graft patency.

[Use of fibrin glue in the prevention of secondary anastomotic stenosis from repair and reconstruction of the injury of the bile duct]

The secondary anastomotic stenosis is often occured from the repair and reconstructive operation of the injured bile duct. It is difficult to treat and the outcome is serious. In order to prevent this complication, the fibrin glue instead of traditional suturing technique combined with inner support was used. Fifty-four hybrid dogs were divided into 3 groups. Group A received Roux-en-y choledochojejunostomy with fibrin glue; group B received Roux-en-y choledochojejunostomy, with a fibrin glue combined support left permanently in the bile duct and group C received Roux-en-y choledocholejejunostomy with fibrin glue combined a support left temporarily in the bile duct. The amount of collagen in the scar was measured at 3/4, 3, 6, 9, 12 months respectively after operation. The results showed: 1. the mature period of scar was shortened from 12 months to 9 months when fibrin glue instead of suture was used in choledochojejunostomy; 2. the mature period of scar was further shortened from 9 months to 6 months when fibrin glue combined with inner support instead of fibrin glue was used in choledochojejunostomy. The conclusions were as follows: 1. fibrin glue could facilitate the healing of wound by inhibiting the formation of scar and accelerrate the maturation of scar; 2. when the inner support was used with fibrin glue in the operation, the mature period of scar could be further shortened; 3. the mechanism of action of the fibrin glue included minimizing the injury, avoiding foreign-body reaction, modifying organization of hematoma, preventing formation of biliary fistular and enhancing intergration and cross-linkage of collagen.

[Supra-aortic arch esophageal mucosa-gastric wall anastomosis with oblique stomach invagination through esophageal bed for patients with esophageal carcinoma undergone esophagectomy]

OBJECTIVE

To reduce impairement of pulmonary function by thoracic stomach and other postoperative complications.

METHODS

One hundred eighteen patients with esophageal carcinoma were treated with supra-aortic arch esophageal mucosa-gastric wall anastomosis with oblique stomach invagination through esophageal bed.

RESULTS

No anastomotic leakage or gastroesophageal reflux occurred. The incidence of anastomotic stricture was 2.5%, that of operative mortality was 0.9%. Cardiopulmonary complications occurred in 11.0%.

CONCLUSION

The procedure may keep the normal anatomical and physiological functions of the thoracic organs and help prevent other complications.

[Myocardial cells action potential and contractive function in hemorrhagic shock in rabbits]

Anesthetized rabbits were subjected to a moderate degree of hemorrhagic shock. Lowering their mean arterial pressure to 5.3 KPa for 3 h, we measured the mean arterial pressure (MBP), left ventricular systolic pressure (LVSP), left ventricular maximum velocities of contraction (dp/dtmax), and myocardial electrical activity. The results of this study demonstrated that LVSP declined in parallel with MBP; that dp/dtmax dropped acutely on the instant of hemorrhagic shock; dp/dtmax went up by 48% on 15 min after shock; then dp/dtmax fell gradually, and by 3 h after shock the dp/dtmax values dropped to 20% of the baseline values; that intracellular sodium and potassium contents increased significantly in the hemorrhagic shocked rabbits; that myocardial resting potential (RP) and action potential amplitude (APH) diminished; and that action potential duration(APD), action potential repolarized 50% duration (APD 50), and repolarized 90% duration (APD 90) were markedly prolonged in the hemorrhagic shock, compared with control. The results suggested that in hemorrhagic shock myocardial cells fast sodium channel was closed while slow sodium and slow calcium channels, were opened; thus sodium and calcium infused and potassium exuded.

[Prenatal diagnosis of fetal nuchal cystic hygroma in 22 cases]

OBJECTIVE

To investigate the early diagnosis and prognosis of fetal nuchal cystic hygroma.

METHODS

72 cases of fetal nuchal cystic hygroma diagnosed in uterus were analyzed retrospectively.

RESULTS

Most of the cases were diagnosed by B ultrasound between 15-26 gestational weeks. 55.9% the multipara had abnormal pregnant history, and 40% (4/10) of fetuses with karyotype performed had chrosome abnormality. Except for fetal deaths and induced abortions, 3 cases had term deliveries: one neonatal death, one was born with hygroma of 5.9 cm x 3.7 cm and transferred for surgery, and the other one with hygroma disappeared at the 37th week and baby was born at 40 week with normal appearance.

CONCLUSIONS

This disease is one of common fetal morphological abnormalities. Few may recover spontaneously but most have poor outcomes.