Extractive fermentation for enhanced propionic acid production from lactose by Propionibacterium acidipropionici

An extractive fermentation process using an amine extractant and a hollow-fiber membrane extractor to selectively remove propionic acid from the fermentation broth was developed to produce propionate from lactose. Compared to the conventional batch fermentation, the extractive fermentation had a much higher productivity ( approximately 1 g/(L.h) or 5-fold increase), higher propionate yield (up to 0.66 g/g or more than 20% increase), higher final product concentration (75 g/L or higher), and higher product purity ( approximately 90%). Meanwhile, acetate and succinate productions in the extractive fermentation were significantly reduced. The improved fermentation performance can be attributed to the reduced product inhibition and a possible metabolic pathway shift to favor more propionic but less acetic and succinic acid production. The process was stable and gave consistent long-term performance over the 1. 5-month period studied. The effects of propionate concentration, pH, and amine content in the solvent on the extractive fermentation were also studied and are discussed in this paper.

[Effects of emodin on the activity of K channel in guinea pig taenia coli smooth muscle cells]

The effects of emodin, cromakalim (KATP channel opener) glybenclamide (KATP channel inhibitor) Ba2+ and TEA on the electrical and contractive activities of the smooth muscle cells in guinea pig taenia coli and the relationship between emodin and four other drugs were studied by using intracellular microelectrode technique and the tension measuring technique. The results are as follows: (1) Emodin enhances the electrical and contractive activities of the smooth muscle cells in guinea pig taenia coli. The effects of emodin depend on its concentration. (2) Emodin can resist the inhibition of cromakalim on the electrical and contractive activities of smooth muscle cells. On the other hand, cromakalim was shown to suppress the effects of emodin. (3) Ba2+, TEA and glybenclamide all can improve the electrical and contractive activities of smooth muscle cells and resist the inhibition of cromakalim. The effects of emodin were found to be similar to that of glybenclamide but different from that of Ba2+ and TEA. The results suggest that the mechanism of action of emodin is to inhibit the activity of KATP channel in the guinea pig taenia coli smooth muscle cells.

[Comparison of the effects of inhaled nitric oxide and intravasculare regitine on pulmonary gas exchange in young dogs with oleic-acid acute lung injury]

In order to find an agent which truly improves hypoxemia of some serious pediatric lung diseases, the authors examined the independent effects of nitric oxide inhalation and regitine infusion on blood gases, intrapulmonary shunt and hemodynamics in young dogs with oleic-acid acute lung injury. After nitric oxide inhalation, the results showed moderate increases in PaO2 and SaO2 (P > 0.05) and a significant decrease in Qs/Q tau ratio (P < 0.01). There was a significant decrease of PAP(P < 0.05), while SAP remained unchanged. After regitine infusion, however, there were marked decreases in PaO2 and SaO2 (P < 0.01); meanwhile, Qs/Q tau rose (P < 0.05). These suggest that with the presence of pulmonary pathology nitric oxide inhalation may alleviate the elevated pulmonary pressure without alteration in systemic artery pressure; so it can improve pulmonary ventilation-perfusion distribution and cause favorable changes in blood gases. On the other hand, regitine, as a non-selective vasodilator, reduces pulmonary artery pressure at the cost of significant worsening of blood oxygenation and systemic hypotension; so its routine use in childhood pulmonary diseases should be cautiously considered.

[Preoperative localized diagnosis of insulinoma by aterial stimulating and venous sampling methods]

OBJECTIVE

To establish a method for bocative diagnoses of insulinoma,

METHOD

Five patients with insulinoma were given locative diagnoses by using ASVS methods which mean injecting calcium stimulatant into pancreatic supplying arteries and then taking blood specimens from henatic vein to gauge the insulin levels. Six samples, each 2 ml, were taken before and 30, 60, 90, 120, 180 seconds after the injection.

RESULTS

If the peak of blood-insulin level was twice or higher than the basic level, the tumor was located in the domain. These results were confirmed operatively in all the five cases.

CONCLUSION

ASVS is an accurate technique to localize insulinoma.

[Genetic polymorphisms of FABP2 and F13A1 loci in Han population]

OBJECTIVE

To find more STR loci usable in forensic medicine and understand the distribution of the genetic polymorphisms of two STR loci FABP2 and F13A1 in the Han population in Chengdu.

METHODS

EDTA-blood specimens were collected from 115 healthy unrelated Han individuals in Chengdu, DNA was extracted using Chelex method. The DNA samples were amplified by PCR technique, and the PAGE horizontal electrophoresis was used for typing of the PCR products.

RESULTS

The allele frequencies were FABP2*1:0.513,FABP2*2:0.096, FABP2*3:0.330, FABP2*4:0.052, FABP2*5:0.009, and 10 genotypes were observed in 115 individuals for FABP2; while for F13A1, the allele frequencies were F13A1*1:0.128, F13A1*2: 0.053, F13A1*3:0.288, F13A1*4:0.527, F13A1*5:0.004 and 10 genotypes were observed in 113 individuals. The result of test for Hardy-Weinberg equilibrium showed that the genotype distribution observed at FABP2 locus was correspondent with the expected.

CONCLUSION

FABP2 may be a useful marker for paternity test or personal indentification of biological stain. On the other hand, more studies need to be done to understand the polymorphism at F13A1 locus in Chinese population because a deviation from Hardy-Weinberg equilibrium has been observed in this Han population.

[Genetic polymorphism of FXIII B subunit in seven Chinese populations]

OBJECTIVE

To understand the distribution of allele frequencies of blood factor XIIIB subunit(FXIIIB) in Chinese populations and evaluate the genetic polymorphism of FXIIIB for the purposes of population genetics and forensic haemogenetics.

METHODS

The genetic polymorphism of FXIIIB subunit in seven Chinese populations was investigated. Isoelectrofocusing technique on polyoacrylamid gels followed by immunoblotting was used to determine the phenotype of individuals in each population sample.

RESULTS

There were three common alleles in all the seven Chinese populations. The frequency of FXIIIB*3 was the highest, that of FXIIIB*2 was the lowest, and the one of FXXIIIB*1 was at the middle. All of them reached to the polymorphism's level. A rare variant allele was also found in some Chinese populations. Comparison of the constituents of FXIIIB phenotypes in the seven populations showed that there was no significant difference (P>0.05). The distribution of the allele frequencies in these populations reflected most likely the mode of the distribution in all Chinese populations. The phylogenetic tree and genetic distance, based on the allele frequencies of FXIIIB differentiated the populations in the world into the main ethnic groups as what other authors reported.

CONCLUSION

FXIIIB is a useful genetic marker for population genetics and forensic haemogenetics.

[Purification and properties of alanine dehydrogenase from Streptomyces lincolnensis]

Alanine Dehydrogenase (L-Alanine: NAD+ oxidoreductase, deaminating, EC 1.4.1.1) was purified from Streptomyces lincolnensis through four steps: (NH4)2SO4 precipitation, DEAE-cellulose 52, Affi-Gel Blue and Sepharose 6B. Molecular weight of the enzyme was determined as 170,000 by gel filtration and concentration gradient PAGE. SDS-PAGE showed only one band of 42,500, demonstrating that ADH from Streptomyces lincolnensis was consisted of four identical subunits. The optimal pH for amination was 9.0, for deamination 9.5. The optimal temperature for both amination and deamination was 50 degrees C. The Km valuse for pyruvate, NH4+, NADH, L-Ala and NAD+ were 2.08 x 10(-4) mol/L, 2.00 x 10(-2) mol/L, 2.38 x 10(-5) mol/L, 1.43 x 10(-2) mol/L and 6.67 x 10(-5) mol/L, respectively.

[Clinical applications of island and myocutaneous flaps]

OBJECTIVE

This is to introduce the experience in clinical applications of the island and myocutaneous flaps.

METHODS

Since 1985 fifteen types of vascularized island and myocutaneous flaps have been applied in 52 cases (21 positions) for the following purposes: repairing traumatic soft tissue defects on the limb, scar contracture, congenital recto-vaginal fistula, reconstructing congenital nasal deformity and rehabilitating function. The non-major artery island flap was used in 47 cases (90.38%) and the retrograde island flap was used in 24 cases (46.15%). The size of the flap ranged from 2.5 cm x 1.5 cm to 15 cm x 12 cm.

RESULTS

All the flaps survived with primary healing. Follow-up for 8 months to 11 years showed aesthetically and functionally satisfactory results in all cases.

CONCLUSION

These island and myocutaneous flaps have rich blood supply and are highly anti-infective. The operation is easy and the success rate is high.

[Changes in sexual hormones and bone metabolism disorder in postmenopausal NIDDM patients]

In the present study the bone mineral content (BMC) was measured with a single photoabsorptionmeter in 31 diabetic menopausal females and 45 normal menopausal females, simultaneously the serum level of estradiol (E2), testosterone (T), parathyroid hormon (PTH) and calcitonin (CT) were measured with radioimmunoassay. The results showed, BMC, E2 and CT in diabetic group were significantly lower than in the control group. The serum level of PTH in diabetic group was significantly higher than in the control group. The multiple regression-analysis showed that chiefly the level of E2 in the diabetic group was closely related with BMC. Serum E2 stimulate directly the osteoblasts for the bone reconstruction and increased the bone tissue sensibility to PTH. CT is the antagonistic hormone of PTH and protects the bone mineralization. Hyperglycemia may cause the damage of ovarium and decreased E2-secretion. The lowered E2 level results in combination with elevated PTH and lowered CT level in serum obviously, in loss of a large amount of bone mineral content and in developing the diabetic osteoporosis.

[Electro-acupuncture effects on experimental spinal cord injury of the cat as evaluated by acid phosphatase detection]

The spinal cords of adult cats were injured at about L1 level by using Allen's method and the animals were divided randomly into 2 groups: a) electro-acupuncture treatment group and b) control group. The acid phosphatase (ACP) was detected at 3 and 7 days after spinal cord injury. The more ACP positive labelings were found in the treatment group than in the control group at both 3 (P < 0.05) and 7 days (P < 0.01) after injury. The results suggested that electro-acupuncture could increase the concentration of ACP of the injured spinal cord and the increased ACP concentration could make worse to the injured spinal cord at early time and improve regeneration during recovery period.

X-ray microanalysis of uterine epithelial cells in culture

The ionic composition of the uterine fluid, secreted by the endometrium, is of importance for fertilization and embryonic development. Little, however, is known about the ion transport mechanisms in the uterine epithelial cells. Because it is difficult to study ion transport in this tissue in situ, a method was developed to culture mouse uterine epithelial cells for X-ray microanalysis in the electron microscope, in order to allow the study of ion transport. Our data suggest the presence of a number of ion transport mechanisms in the cultured uterine epithelial cells. The cells appear to possess a ouabain-sensitive Na(+)-K(+)-ATPase, an amiloride-sensitive Na(+)-H+ antiporter, cAMP- and Ca(2+)-activated chloride channels, and volume-activated chloride efflux and influx mechanisms. In addition, chloride efflux can be stimulated by cholinergic and alpha-adrenergic agonists. Only a few of these mechanisms had been studied previously in the uterine epithelium.

[Inhibitory effect of ganciclovir on the HSV1-tk positive subcutaneous tumors transplanted with human ovarian cancer in nude mice]

OBJECTIVE

To investigate the inhibitory effect in vivo of ganciclovir (GCV) on the growth of human ovarian cancer cells (AO) transducted with the thymidine kinase gene of herpes simplex virus I type (HSV1-tk).

METHODS

Tumors were induced in nude mice by subcutaneous injection of AO cells and AO cells carried with HSV1-tk gene from China strain (AO/HSV1-tk cells). When the growing tumors were visible, GCV was injected daily into the peritoneum of the nude mice.

RESULTS

The average weights of survived AO/HSV1-tkc tumors and AO tumors treated with GCV were 0.087 +/- 0.036 g and 0.661 +/- 0.260 g respectively. Most of the survived AO/HSV1-tkc cells treated with GCV were characterized by hypertrophy and necrosis, but their nuclear chromatins predominantely took the forms of heterchromatins.

CONCLUSIONS

GCV could effectively inhibit the growth of HSV1-tk positive human ovarian cancer cells in vivo, but the nuclei of the survival tumor cells appeared to proliferate actively. As the same results of in vitro experiments, this may suggest that HSV1-tk/GCV gene therapeutic system might be combined with S-phase chemotherapy to increase the long-term effect.

Four-channel self-focus computer-generated hologram

A new type of computer-generated hologram (CGH) is described in this research. Upon the base of a two-channel CGH, it can generate four independent images in four different directions with the addition of positive or negative quadratic phase factors on the object spectrum; it has the character of self-focus. Results of the experiment are provided.

Rail supporting transducer posts for three-dimensional force measurement

Parallel bars supported on transducer posts were designed, instrumented and calibrated to measure three-dimensional (3-D) forces applied to the rails. These instrumented rails were designed for measuring forces applied by paraplegic patients during development and evaluation of functional electrical stimulation (FES) patterns for standing, side stepping, and ascending and descending stairs. The focus of this study was on the adaptation of the system for measuring support forces during stair climbing and descent. The specific problems with crosstalk among the three axes, nonlinearity, and hysteresis were investigated. In this design, the crosstalk between axes was less than 5%, nonlinearity was less than 2% of full scale, and force accuracy was better than 5%.

The selective recognition of antibody IgY for digestive system cancers

Biological methods for cancer therapies are very important. A small and efficient target carrier is the key component for anti-cancer drugs. In our laboratory, the antibody IgY was extracted from egg yolk of a SPF hen. The SPF hen was immunized with an antigene of P110 protein which was purified from human stomach cancer MGC-803 cells. Results indicated that the antibody IgY can specifically recognize gastrointestinal system cancers. It may become an important carrier for antitumorigenic drugs.

Developmental changes in the dendritic architecture of salt-sensitive neurons in the nucleus of the solitary tract

Recent studies have provided evidence that brainstem gustatory neurons undergo substantial dendritic growth during a period of postnatal development that coincides with the maturation of their response to salts, suggesting a relationship (perhaps causal) between the physiology and morphology of developing salt-sensitive neurons. In an initial effort to explore this issue, we used extracellular and intracellular recording and intracellular labeling techniques to examine the structure and function of individual gustatory neurons in the rostral nucleus of the solitary tract (rNST) of young (postnatal day [P] 22-28) and adult rats. We found that P22-28 cells that responded to all three of the salts in our taste array had a greater dendritic length, a greater cell volume, and more dendritic branches than the cells that responded to one salt. As a group, taste-sensitive neurons in P22-28 animals had a higher maximum dendritic branch order and a trend toward more dendritic branch points than gustatory neurons in adult animals. The dendritic arbors of P22-28 taste neurons that responded to all three salts were larger (greater surface area and volume), more extensive in the rostrocaudal axis and exhibited a higher maximum branch order, more branch points and higher swelling density than adult cells that responded to all three salts. These results demonstrate that the morphology of salt-sensitive gustatory neurons in developing animals is closely related to the number of salts that evoke a response. The data also support the postulate that gustatory neurons in the rat brainstem undergo substantial dendritic remodeling between the fourth week of life and adulthood. Dendritic remodeling may play an important role in the maturation of the rNST response to NaCl.

Comparison of styrene-7,8-oxide adducts formed via reaction with cysteine, N-terminal valine and carboxylic acid residues in human, mouse and rat hemoglobin

The reactive metabolite of styrene, styrene-7,8-oxide (SO), reacts with a variety of nucleophilic sites in hemoglobin (Hb) to form SO-Hb adducts. Following the in vitro incubation of SO with blood from humans, NMRI mice and Sprague-Dawley rats, the second-order reaction rate constants were determined for the reaction of SO with cysteine (through both the alpha- and beta-carbons of SO), N-terminal valine (through the beta-carbon of SO), and carboxylic acid (presumably through both the alpha- and beta-carbons of SO) residues in Hb. The rate constants for cysteine adducts vary dramatically between species [2.04, 10.7, 133 L (mol Hb)-1 h-1 (alpha binding) for humans, mice and rats, respectively] and [0.078, 2.16, 20.4 L (mol Hb)-1 h-1 (beta binding), respectively]. The considerably higher rate of reaction with cysteine in rat Hb probably reflects the presence of an additional cysteine residue at position beta 125. Although the rate constants for valine adducts (1.82, 0.80, 0.29 L (mol Hb)-1 h-1, respectively) and COOH adducts (3.55, 1.94, 2.37 L (mol Hb)-1 h-1, respectively) are much more consistent, the inter-species differences are statistically significant for the reaction of SO with the N-terminal valine of Hb. Following the i.p. administration of styrene to mice and styrene and SO to rats, the levels of adducts at each of these sites were used in conjunction with the calculated rate constants to predict the integrated blood doses of SO. While the SO doses predicted from cysteine and valine adducts were very similar, that based upon COOH-binding was significantly different, presumably due to the instability of SO-COOH adducts. This research affirms the use of both cysteine and valine adducts, but not carboxylic acid adducts, as biomarkers of exposure to styrene and SO.

Rac1 mediates collapsin-1-induced growth cone collapse

Collapsin-1 or semaphorin III(D) inhibits axonal outgrowth by collapsing the lamellipodial and filopodial structures of the neuronal growth cones. Because growth cone collapse is associated with actin depolymerization, we considered whether small GTP-binding proteins of the rho subfamily might participate in collapsin-1 signal transduction. Recombinant rho, rac1, and cdc42 proteins were triturated into embryonic chick (DRG) neurons. Constitutively active rac1 increases the proportion of collapsed growth cones, and dominant negative rac1 inhibits collapsin-1-induced collapse of growth cones and collapsin-1 inhibition of neurite outgrowth. DRG neurons treated with dominant negative rac1 remain sensitive to myelin-induced growth cone collapse. Similar mutants of cdc42 do not alter growth cone structure, neurite elongation, or collapsin-1 sensitivity. Whereas the addition of activated rho has no effect, the inhibition of rho with Clostridium botulinum C3 transferase stimulates the outgrowth of DRG neurites. C3 transferase-treated growth cones exhibit little or no lamellipodial spreading and are minimally responsive to collapsin-1 and myelin. These data demonstrate a prominent role for rho and rac1 in modulating growth cone motility and indicate that rac1 may mediate collapsin-1 action.

[Clinical diagnostic valuation cine magnetic resonance coronary angiography]

OBJECTIVE

To assess the ability of imaging coronary arteries noninvasively with magnetic resonance angiography technique (MRCA) and its diagnostic value in coronary artery disease.

METHODS

MRCA was performed on 33 subjects, including 12 healthy adult volunteers and 21 patients with available recent X-ray contrast angiography (XCA) results. MRCA technique consisted of a gradient echo sequence (Turbo-Cine), two-dimensional acquisition, fat suppression, peripheral gating. Subjects were imaged in supine position using a standard body coil, without breath-hold.

RESULTS

All 33 subjects were imaged successfully. Identification of the coronary artery was possible for the right coronary, left main stem, left anterior, and left circumflex arteries respectively in 97%, 100%, 91% and 91% with a visualized mean length of 51 +/- 15 (28-80 mm), 11 +/- 4 (4-22 mm), 44 +/- 13 (24-66 mm), 40 +/- 12 (20-66 mm). In the 21 subjects with available XCA results, 78% (29/37) proximal stenoses of the coronary arteries were detected with MRCA.

CONCLUSION

At current stage, MRCA can depict most of the hemodynamically significant proximal stenoses but not the distals. This procedure can be used as an alternative imaging application under certain clinical indications.

Risk of relapse in leprosy after fixed-duration multidrug therapy

Between 1986 and 1995, 8307 leprosy patients have completed fixed-duration multidrug therapy (FD-MDT) and were followed annually for possible relapse. The mean relapse rate for multibacillary (MB) leprosy is 0.15/1000 person-years (py) and for paucibacillary (PB) 0.55/1000 py. There is no difference in the relapse rates between patients with or without chemotherapy before FD-MDT. In MB patients, the five relapses occurred between 4 and 7 years; in PB patients, five relapses occurred at 4-5 years after FD-MDT. Six additional PB relapses self-reported 1-4 years after the 5-year surveillance period and were not included in the relapse rates. Most PB patients relapsed into MB due to wrong classification and insufficient therapy. For the known 62 irregular MB patients the cumulative relapse rate is 6.5%.

Alternative method of subtyping the A subunit of coagulation factor XIII (FXIIIA)

An alternative isoelectric focusing method for the A subunit of coagulation factor XIII (FXIIIA) subtyping is described which employs three different carrier ampholytes, pH 4-6.5, pH 5-6 and pH 5-8 (2:2:1), and sample application at the anode. With this technique ten common subtypes, including a variant, were clearly and reliably identified in Japanese and Chinese population samples.

Maternal HIV-1 viral load and vertical transmission of infection: the Ariel Project for the prevention of HIV transmission from mother to infant

Most HIV-1 infections of children result from mother-to-infant transmission, which may occur perinatally or postnatally, as a consequence of breast feeding. In this study, the influence of maternal viral load on transmission of infection to infants from non-breast-feeding mothers was examined using samples of plasma and peripheral blood mononuclear cells (PBMCs) collected at several time points during pregnancy and the 6-month period after delivery. These samples were analyzed by several quantitative methods, including virus cultures of PBMCs and polymerase chain reaction (PCR) assays for HIV-1 RNA in plasma and DNA in PBMCs. The risk of transmission increased slightly with a higher viral load, but transmission and nontransmission occurred over the entire range of values for each assay. No threshold value of virus load was identified which discriminated between transmitters and nontransmitters. We also noted a significant rise in viral load and a decline in CD4+ lymphocytes in the six months after delivery. These findings suggest that a high maternal viral load is insufficient to fully explain vertical transmission of HIV-1. Additional studies are needed to examine the post-partum increase in viremia.

Neuroanatomical substrates of late-life minor depression. A quantitative magnetic resonance imaging study

OBJECTIVE

To examine the neuroanatomical correlates of late-life minor depression using magnetic resonance imaging.

DESIGN

Cross-sectional quantitative magnetic resonance imaging study of elderly patients with minor depression and age-matched controls.

SETTING

Patients and controls were recruited from the community through advertisements to the Section of Geriatric Psychiatry, University of Pennsylvania, Philadelphia.

PARTICIPANTS

Our sample included 18 subjects diagnosed as having minor depression using the modified Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, research criteria and 31 controls without depression. Patients were free of other central nervous system disease and both groups had comparable degrees of medical comorbidity.

MAIN OUTCOME MEASURES

All images were acquired on a 1.5-T scanner and absolute and normalized quantitative measures of global and focal brain and cerebrospinal fluid volumes were compared between groups.

RESULTS

Prefrontal lobe volume was significantly smaller in the group with minor depression (P = .002) compared with controls after controlling for age, sex, and age by sex interactions. More global measures of brain and cerebrospinal fluid volumes were comparable in both groups.

CONCLUSIONS

These data suggest that focal prefrontal atrophy may provide an important neuroanatomical substrate in late-life minor depression.

Effects of nicotine on the uterine epithelium studied by X-ray microanalysis

The composition of the uterine fluid is of importance for the development of the embryo. The ionic composition of the uterine fluid is determined by transport processes in the uterine epithelium. The aim of the present study was to investigate whether nicotine can affect the ion transport processes and ultrastructure of the uterine epithelium in mouse and rat. The effects of nicotine on the uterine epithelium were compared with those on kidney and liver. Nicotine was administered to mice as an intraperitoneal injection of a 1 microgram/l nicotine solution twice daily for 8 days, or in the drinking water (108 microM nicotine) for 15 days, whereas rats received nicotine in their drinking water for 10 days (54 or 108 microM nicotine). In addition, primary cultures of endometrial cells were exposed to nicotine in vitro. Changes in morphology were examined by transmission electron microscopy and changes in elemental content by X-ray microanalysis. Nicotine caused a significant decrease in the concentrations of Na, K, and Cl in the uterine fluid and in the endometrial cells in situ. Similar changes in elemental concentrations were observed in endometrial cells in vitro. Ultrastructural changes in endometrial cells included swollen and damaged mitochondria. In liver and kidney much smaller effects of nicotine on the elemental composition of the cells were observed. However, marked ultrastructural effects were seen in the kidney: a reduction in mitochondrial size and an increase in lysosomal volume. It is concluded that nicotine directly interferes with fluid transport across the uterine epithelium.

X-ray microanalysis of uterine secretion in the mouse

In an attempt to characterize ion transport mechanisms in the uterine epithelium the effect of diuretics on the elemental composition of the uterine secretion was investigated by X-ray microanalysis. Mice were treated with a variety of diuretics and Sephadex beads were incubated in situ in the uterus where they absorbed the uterine secretion. In animals treated with furosemide, bumetanide, or amiloride, the concentration of Na, K, and Cl in the uterine secretion was significantly decreased. After treatment with acetazolamide, only the K concentration was significantly decreased. Treatment with diuretics also decreased the concentration of P and S in the uterine secretion, indicating that less mucus was absorbed to the Sephadex beads. Transmission electron microscopy confirmed that treatment with amiloride and furosemide decreased the amount of mucus covering the epithelium. A possible explanation is that because of lack of water, the uterine mucus cannot leave the lumen of the uterine glands and reach the surface of the epithelium where the beads are. The data strongly suggest that Na+, K+, and Cl- transport in the uterine epithelium is dependent on a basolaterally situated Na(+)-(K+)-Cl(-)-cotransport mechanism. Disturbance of normal ion and water transport apparently affects the composition and consistency of the mucus, which may help explain abnormalities in cervical mucus in patients with cystic fibrosis.

[Effects of amniotic fluid embolism-like plasma on isolated perfused rabbit lungs]

OBJECTIVE

In order to investigate whether amniotic fluid could induce the release of mediators from blood cells which would damage the lungs, an isolated perfused rabbit lung (IPRL) was exposed to amniotic fluid embolism-like plasma (AFEP) and the injury of AFEP to lungs and the protective effects of ibuprofen were studied.

METHODS

10 ml human amniotic fluid and 50 ml heparized rabbit blood were incubated together with or without ibuprofen (600 micrograms) at 37 degrees C for 30 min and centrifuged. Supernatants were taken and were referred to as AFEP or ibuprofen AFEP. IPRL was perfused with AFEP, ibuprofen AFEP, simple amniotic fluid (SAF), supernatant of amniotic fluid (SnAF), rabbit plasma (RP) and control NS. The changes of pulmonary artery pressure (PAP), respiratory pressure (RP) and lung weight were recorded by computer and compared with control NS group.

RESULTS

In groups of SAF, SnAF and RP PAPs were slightly elevated (0.13-0.6 kPa, P > 0.05), and lung weights were not changed. AFEP induced the increase of PAP (3.52 +/- 0.64 kPa, P < 0.05) and lung weight (4.0 +/- 1.0 g, P < 0.01) with the development of lung edema. Administration of ibuprofen prevented partially the APEP-induced increase of PAP (1.87 +/- 0.43 kPa, P < 0.05) and lung weight (0.4 +/- 0.3 g, P < 0.01).

CONCLUSION

Amniotic fluid may induce the release of mediators from blood cells, and the latter is the important cause resulting in the pathological changes of lungs in amniotic fluid embolism. Ibuprofen may reduce partially the APEP-induced lung injury.

[Study on Servo-null method for direct measurement of microvascular pressure by micropuncture technique]

The dynamic microvascular pressures in the mesentery of spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were measured and recorded by using the Servo-null microvascular pressure measuring system (Model 4A, IPM, Inc., San Diego, USA) with glass micropipettes whose tips were 1.0-5.0 microns in diameter and had been beveled very sharply at an angle of 25 degree. Microvascular pressures were measured in two groups of microvessels: large, 25-45 microns; small, 15-25 microns. Mean microvascular pressures (Pm) of large and small arterial microvessels in SHR were 6.0 +/- 7.0 kPa and 4.8 +/- 0.6 kPa, respectively. In WKY rats, Pm were 4.2 +/- 0.6 kPa and 3.6 +/- 0.6 kPa, respectively. Pm of comparable types of arterial microvessels in SHR and WKY rats was significantly different. No significant difference of Pm in small venous vessels was found between SHR and WKY rats.

Standardization of low attenuation area versus total lung area in chest X-ray CT as an indicator of chronic pulmonary emphysema

We examined the methods for measuring the LAA% (100 x low attenuation area/total lung area) on thoracic X-ray CT scans in order to develop a useful indicator of chronic pulmonary emphysema (CPE). First, we modified the method for calculating the LAA% to be applicable by the programming tool installed in a commercially available CT machine in order to minimize manual procedures. This new method proved to be applicable in all CT machines produced after 1987. Second, we examined the difference in the Hounsfield Unit (HU) between different CT machines using two kinds of phantoms. One phantom was composed of Styrofoam, which has a density similar to the low attenuation areas. The other phantom was composed of Styrofoam and water, which has a density similar to the lung. We proved that the difference of LAA% with the correct value was 5% at maximum among four different CT machines. Thus, the phantom developed in the present study may play an important role in the standardization of HU. Finally, the possibility of decreasing the X-ray levels was examined. Twenty-five percent of the standard electrical current provided the same LAA% in cases where the subject was an established CPE patient, whereas the LAA% was overestimated in subjects with a normal LAA% value. However, a correction using a linear regression equation may be possible in the latter cases. It may be concluded that LAA% analysis can easily be performed in many city hospital, without much investment of manual procedures or any corrections to the HU levels between different CT machines. This method may be useful as a routine follow up for CPE patients because of the smaller irradiated dose given when using a CT machine.

Molecular characterization of a novel, developmentally regulated small embryonic chaperone from Caenorhabditis elegans

Low molecular weight chaperones inhibit protein aggregation and facilitate refolding of partially denatured polypeptides in cells subjected to physical and chemical stresses. The nematode Caenorhabditis elegans provides a system amenable for investigations on roles for chaperone proteins in normal homeostasis and development. We characterized a C. elegans gene and cDNAs that encode a novel, small embryonic chaperone-like protein (SEC-1) that is composed of 159 amino acids. The central core of SEC-1 (residues 45-126) is approximately 40% identical with a corresponding segment of mammalian Hsp27 and alphaB crystallin. Expression of SEC-1 in Escherichia coli confers thermotolerance on the bacterium. SEC-1 mRNA is evident only in C. elegans oocytes and developing embryos. Translation and accumulation of SEC-1 protein is temporally coupled with a prolonged burst of intense protein synthesis and rapid mitogenesis during early embryogenesis. As the rate of protein synthesis decreases during late embryogenesis, levels of SEC-1 and its cognate mRNA decline precipitously. Induction/deinduction of SEC-1 is precisely regulated by intrinsic developmental factors rather than extrinsic stresses. In vivo injection of C. elegans oocytes with antisense oligonucleotides that complement the 5'-end of SEC-1 mRNA arrests nematode development at an early stage after fertilization. Thus, SEC-1 appears to be adapted to perform essential functions in early embryogenesis.

Alterations in H-ras1 promoter conformation during N-nitroso-N-methylurea-induced mammary carcinogenesis and pregnancy

We previously demonstrated that H-ras1 oncogene mutations detected in N-nitroso-N-methylurea (NMU)-induced mammary tumors arose as background mutations within rat mammary cells (RMCs) and that NMU promoted the outgrowth of these preexisting mutants. We have now detected a putative DNA structure in the H-ras1 promoter of RMCs in vivo that was absent in NMU-induced mammary tumor cells. Analysis of the promoter in RMCs as a function of time after exposure to carcinogens indicated that NMU, but not 7,12-dimethylbenz(a)anthracene, initiated the loss of this structure with a half-life of 7 days. Although loss of the structure was irreversible in cells that gave rise to tumors, it was restored in normal RMCs by 120 days after exposure and was present in normal RMCs of animals bearing tumors, even 1 year after NMU exposure. The structure was also abrogated in RMCs during pregnancy and restored after lactation was terminated, suggesting that reversible regulation of the structure by hormones contributed to normal RMC growth. Thus, NMU may promote abnormal RMC growth by mimicking the effects of hormones on DNA conformation. We hypothesize that the NMU-induced alterations in promoter conformation irreversibly deregulates H-ras1 expression in initiated cells, thereby increasing the phenotypic penetrance of the conditional H-ras1 mutations.

The role of a mutant CCR5 allele in HIV-1 transmission and disease progression

A 32-nucleotide deletion (delta 32) within the beta-chemokine receptor 5 (CCR5) gene has been described in subjects who remain uninfected despite extensive exposure to HIV-1. This allele was found to be common in the Caucasian population with a frequency of 0.0808, but was not found in people of African or Asian ancestry. To determine its role in HIV-1 transmission and disease progression, we analyzed the CCRS genotype of 1252 homosexual men enrolled in the Chicago component of the Multicenter AIDS Cohort Study (MACS). No infected participant was found to be homozygous for the delta 32 allele, whereas 3.6% of at-risk but uninfected Caucasian participants were homozygous, showing the highly protective role of this genotype against sexual acquisition of HIV-1. No evidence was found to suggest that heterozygotes were protected against HIV-1 infection, but a limited protective role against disease progression was noted. The delta 32 allele of CCR5 is therefore an important host factor in HIV-1 transmission and pathogenesis.

[The changes in plasma nitric oxide level in normal pregnant women and pregnancy induced hypertension]

OBJECTIVE

To investigate the relationship between nitric oxide (NO) level and pregnancy induced hypertension (PIH).

METHODS

The plasma level of NO in 36 cases of normal pregnant women (normal pregnancy group), 23 cases of PIH (PIH group), and 16 cases of non-pregnant women (control group) were measured and compared using fluorophotometry.

RESULTS

The NO level of normal pregnancy group was significantly higher than that of control group (P < 0.01), particularly in the second trimester of pregnancy. The NO level of PIH was significantly lower than that of third trimester of normal pregnancy (P < 0.01), and it decreased as the disease became severe.

CONCLUSIONS

Decreased synthesizing and releasing of NO might play an important role in pathogenesis of PIH.

[Percutaneous transluminal angioplasty for the treatment of occlusion of proximal subclavian artery]

Percutaneous transluminal angioplasty (PTA) is a well-established treatment for patients with stenosis of limb arteries. However, its efficacy for treatment of severe stenosis and occlusions of the subclavian artery is unclear. We attempted to recanalize the subclavian artery in 30 patients with severe stenosis or total occlusion of proximal subclavian artery and successful outcomes were seen in 27 cases (90%). In two patients the regional arterial thrombolysis with the PTA prcedure we used was found successful. There was no severe complications. During an average 6-month follow-up stenosis recurred in 2 patients, but the subclavian artery was recanalized by repedted PTA.

Analysis of tear fluid by CE/LIF: a noninvasive approach for glucose monitoring

Nanoliter volumes of human tear fluid were collected by means of a capillary tube without inducing tearing and were analyzed for glucose content. The tear fluid was subjected to two enzymatic reactions to generate a fluorescent compound that is proportional to the concentration of glucose in the sample. CE with laser-induced fluorescence (LIF) detection was used to monitor the fluorescent species generated, hence glucose in the tear samples. The reproducibility of the method for six different preparations was < 9% relative standard deviation (RSD). The procedure was compared with the glucose dehydrogenase method for the determination of glucose in blood before using it to determine glucose in tear fluid. Blood and tear samples were collected from six healthy human subjects. The results showed that the higher glucose content in tear samples is consistent with the higher glucose content in blood samples. The glucose concentration of the tear samples analyzed ranged from 128 to 166 microM, and that of blood ranged from 3.3 to 4.3 mM.

[Genetic polymorphism of antithrombin III in five Chinese populations]

The genetic polymorphisms of antithrombin III (AT III) in 5 Chinese populations were studied by isoelectric focusing on polyacrylamide gels followed by immunoblotting. The products of two alleles at the antithrombin III locus together with 1 AT III anodic variant and 3 cathode variants were observed. The results revealed that the predominant allele of AT III blood group system in Chinese populations was AT III *1, with frequencies between 0.9773-0.9850. Frequencies of AT III *2 ranged from 0.0091 to 0.0169. These results indicate that the polymorphic information content of AT III blood group system in Chinese populations is limited.

Structure and function of gustatory neurons in the nucleus of the solitary tract: II. Relationships between neuronal morphology and physiology

This study employed intracellular recording and labeling techniques to examine potential relationships between the physiology and morphology of brainstem gustatory neurons. When we considered the neuronal response to the four "prototypic" tastants, we were able to demonstrate a positive correlation between breadth of responsiveness and the number of dendritic branch points. An analysis of the response to eight tastants also revealed an association between dendritic spine density and the breadth of responsiveness, with more narrowly tuned neurons exhibiting more spines. Interestingly, a neuron's "best response" was a relatively poor predictor of neuronal morphology. When we focused on those neurons that responded to only one tastant, however, a number of potentially important relationships became apparent. We found that the cells that only responded to quinine were smaller than the neurons that only responded to NaCl, HCl, or sucrose. The HCl-only neurons, however, were more widespread in the rostrocaudal dimension that the neurons that only responded to NaCl. A number of additional structure-function relationships were identified when we examined the neuronal response to selected tastants. We found that neurons that responded to sucrose but not quinine, as well as neurons that responded to quinine but not sucrose, were more widespread in the mediolateral dimension than neurons that responded to both sucrose and quinine. We also discovered that the neurons that responded to NaCl, but not to NH4Cl or KCl, were larger than neurons that responded to all three salts. We believe that these results support the hypothesis that there are relationships between the structure and function of gustatory neurons in the nucleus of the solitary tract, with the data highlighting the importance of three themes: 1) the relationship between dendritic specializations and tuning, 2) the relationship between dendritic arbor orientation and response properties, and 3) the potential importance of stimulus-specific neurons.

Determination of albumin and hemoglobin adducts in workers exposed to styrene and styrene oxide

Hemoglobin and albumin adducts of the carcinogen styrene-7,8-oxide (SO) were measured in 48 workers exposed to both styrene and SO in a boat manufacturing plant. Personal exposures to both substances were measured repeatedly over the course of 1 year (styrene:0.9-235 mg/m3 with a mean of 64.3 mg/m3 for 48 subjects; S0: 13.4-525 mu g/m3 with a mean of 159 mu g/m3 for 20 subjects). Cysteine and carboxylic acid adducts of SO with hemoglobin and albumin were assayed on one or more occasions for each subject. The proteins were subjected to base hydrolysis to release styrene glycol, representing carboxylic acid-bound SO, and were then treated with Raney nickel to release 1-phenylethanol and 2-phenylethanol, representing cysteine-bound SO. These three analytes were extracted, derivatized, and analyzed by gas chromatography-mass spectrometry. No evidence was found of any exposure-related increase in hemoglobin adducts. In contrast, albumin adducts were found to increase with exposures to either styrene or SO, the latter apparently being more important. This suggests that exposure to low levels of SO in the air may be important among workers in the reinforced plastics industry. Significant levels of SO adducts of albumin and hemoglobin were also detected in proteins obtained from persons without occupational exposure to styrene or to SO. This finding opens the possibility that SO is either a dietary or an environmental contaminant or is produced endogenously.

[Direct genotyping and antenatal diagnosis of deletional alpha-thalassemia of the southeast Asian type by polymerase chain reaction technique]

OBJECTIVE

To study the gene of deletional alpha-thalassemia of the Southeast Asian type (SEA) and to perform the antenatal diagnosis.

METHODS

A new method of polymerase chain reaction technique using three primers bridging the breakpoints was carried out for carrier detection and antenatal diagnosis of deletional alpha-thalassemia of the Southeast Asian type. A DNA fragment of about 630bp in size was amplified in case of--SEA alleles, while a 224 bp fragment was amplified in samples without the deletion. Homozygotes, heterozygotes, and normal subjects could be clearly distinguished with the present method.

RESULTS

We used this method in the genotyping and antenatal diagnosis of 10 high risk pregnancies of alpha-thalassemia. 2 homozygotes, 4 heterozygotes, and 4 normal infants were found.

CONCLUSION

The present method is simple and rapid in detection of carriers and antenatal diagnosis of the alpha-thalassemia of southeast Asian type.

[The value of endoscopic ultrasonography in the diagnosis of ampullary carcinoma]

The value of endoscopic ultrasonography (EUS) for diagnosing ampullary carcinoma was assessed in 14 patients. The diagnostic accuracy, the chariacteristics of the images and the preoperative invasion of the carcinoma were studied. The results showed that: (1) The lesions were clearly demonstrated in all cases (100.0%) and the diagnostic accuracy of EUS was 78.6%, which was better than that of transabdominal ultrasonography and CT (P < 0.05), but similar to that of endoscopic retrograde cholangio-pancreatography (ERCP) (P > 0.05). Three patients with pancreatic carcinoma were misdiagnosed as ampullary carcinoma by EUS, because the carcinoma was situated at the head of the pancreas and infiltrated to the duodenal wall. (2) Hyperecho image was obtained in 81.8% of the cases and hypoecho image in 18.2% of the cases. (3) The accuracy of EUS in demonstrating the invasion of the carcinoma into the duodenal wall, common bile duct, pancreatic duct and the head of the pancreas was 83.3%, 66.7%, 50.0% and 33.3% respectively and the lymph node matastasis of the carcinoma was 100.0%.

[The study of relationship between c-erbB2 expression and cytoimmunology in ovarian carcinoma and its antisense regulation]

The relationship between c-erbB2 expression and cytoimmunology in ovarian carcinoma cell lines was studied; the synthesized and modified c-erbB2 antisense oligodeoxynucleotide was tested for its ability to reduce over-expression of c-erbB2. The results showed that over-expression of c-erbB2 in ovarian carcinoma could induce resistance to tumor necrosis factor (TNF) and lymphokine activated killer (LAK) cells but had no effect on H2O2; c-erbB2 antisense oligodeoxynucleotide could specifically reduce the over-expression of c-erbB2 and increase the sensitivity of ovarian cancer targets to lysis by TNF and LAK cells.

Cell types in the rostral nucleus of the solitary tract

The rostral subdivision of the nucleus of the solitary tract (rNST) is not laminated or otherwise organized into clearly segregated cell types. Although a variety of experimental approaches have yielded a wealth of information, the definition of cell types in this nucleus has been difficult, as reflected in the sometimes contradictory literature on morphological cell typing. The present review discusses how rNST neurons have been classified in the past and adds to the evidence that distinct neuron types exist in this nucleus. Consistencies in the literature, as well as inconsistencies among studies, are discussed. Furthermore, we have included a summary of our own results that help provide additional data relevant to cell typing. The definition of cell types in other central nervous system nuclei has helped our understanding of the organization of these nuclei and our understanding of the relationships between the morphology and function of neurons. It is hoped that this synthesis of the extant literature will facilitate the many ongoing efforts to correlate neuronal morphology and physiology in the gustatory system.

[Protective effects of methanolic extract of Oenanthe stolonifera (Roxb.) Wall. ex DC. on myocardial injury induced by ischemia and reperfusion in rats]

The methanolic extract Oenanthe stoloni fera iv, pretreatment can significantly prevent the arrhythmias induced by myocardial ischemia and reduce the myocardial infarct size in rats. It can also markedly prevent myocardial ischemia and reperfusion-induced arrhythmias. In addition, the methanolic extract of Oenanthe stoloni fera (100 mg/kg i.v.) helps significantly to decrease the MDA content and preserve the SOD activity in plasma.