Differentiation and death of premyelinating oligodendrocytes in developing rodent brain

Previous studies have indicated that newly formed oligodendrocytes are dynamic cells whose production, survival, and differentiation depend upon axonal influences. This study has characterized the appearance and fate of newly formed oligodendrocytes in developing rat brain. Oligodendrocytes appear in predictable locations and radially extend DM-20-positive processes that cover 80-microm domains in the cortex and 40-microm domains in the corpus callosum. These premyelinating oligodendrocytes have one of two fates: they myelinate axons or degenerate. Between 7 and 21 d after birth, approximately 20% of premyelinating oligodendrocytes identified in the cerebral cortex were degenerating. Oligodendrocytes that ensheathed axons expressed and selectively targeted proteolipid protein to compact myelin and did not degenerate. These observations support the hypothesis that axonal influences affect oligodendrocyte survival, differentiation, and expression of proteolipid protein gene products.

Undifferentiated U937 cells transfected with chemoattractant receptors: a model system to investigate chemotactic mechanisms and receptor structure/function relationships

Transfection of either the C5a receptor or the formyl peptide receptor into undifferentiated U937 cells generated continuously growing cell lines that stably expressed these receptors. The transfected cells displayed significant numbers of cell surface receptors that had ligand binding properties similar to fully differentiated U937 cells. Undifferentiated transfected U937 cells were capable of a ligand-specific calcium flux and showed migratory responses that were qualitatively and quantitatively similar to differentiated cells and were specific for each chemoattractant. Moreover, the chemotactic response could be desensitized by preincubating the cells in a high concentration of ligand and could be blocked by pertussis toxin. These results demonstrate that undifferentiated U937 cells possess the subcellular signaling apparatus and machinery necessary to generate a motile response and that the only missing component for chemotaxis is expression of a chemoattractant receptor. In addition, the results demonstrate that undifferentiated U937 cells transfected with chemoattractant receptors provide a defined model system to study receptor structure/function relationships and may be used to investigate receptor-mediated chemotactic responses in a relevant human myeloid cell.

Round ligament varices in pregnancy mimicking inguinal hernia: an ultrasound diagnosis

A case of uncomplicated round ligament varices mimicking an irreducible inguinal hernia in the third trimester of pregnancy is presented. The clinical and ultrasound features, pathophysiology and the role of conservative management are discussed. Non-surgical treatment led to spontaneous regression after delivery.

Acyl-coenzyme A:cholesterol acyltransferase

Due to its presumed role in regulating cellular cholesterol homeostasis, and in various pathophysiological conditions, acyl-coenzyme A:cholesterol acyltransferase (ACAT) has attracted much attention. Cloning the ACAT gene provides the necessary tool to advance molecular studies of this enzyme. The topics reviewed in this chapter include the pathophysiological roles of ACAT, the biochemistry and molecular biology of the ACAT protein and the ACAT gene, and the mode of regulation by sterol or nonsterol agents in mammalian cells. In addition, we present a working model linking the presumed allosteric property of ACAT with cholesterol trafficking into and out of the endoplasmic reticulum.

Routine chest roentgenography on admission to intensive care unit after heart operations: is it of any value?

The need for routine immediate postoperative chest roentgenography after heart operations has recently been questioned. In this study we investigated the impact of routine postoperative chest roentgenography on treatment instituted in the cardiovascular intensive care unit immediately after heart operations done via median sternotomy. A total of 404 random patients admitted to the cardiovascular intensive care unit underwent clinical (positioning of endotracheal tube, nasogastric tube, and pulmonary artery catheter) and laboratory (oxygenation) assessment by a cardiovascular intensive care unit physician according to a strict protocol. After clinical assessment, chest roentgenography was done for all admitted patients and the findings reviewed by the same physician. Pathologic conditions noted were recorded on the study form together with any required treatment. Eighteen patients (4.5%) out of 404 required intervention because of abnormalities detected by the chest x-ray film but not predicted by the initial physical and laboratory assessment. None of the pathologic conditions detected was life threatening. We conclude that chest roentgenography done on admission to the cardiovascular intensive care unit should be done only if clinical and laboratory assessment indicate the possibility of underlying pathologic conditions that can only be confirmed or diagnosed by chest roentgenography.

[Effects of ginkgo plus on hypoxic pulmonary hypertension in rats]

We examined the effects of Ginkgo Plus on the pulmonary hemodynamics and right ventricular hypertrophy in rats exposed to isobaric chronic hypoxia. The rats treated with chronic hypoxia developed pulmonary hypertension and right ventricular hypertrophy. Ginkgo Plus reduced significantly the hypoxia-induced increase of mean pulmonary arterial pressure and pulmonary vascular resistance as well as the ratio of right ventricular weight vs left ventricular plus septal weights. The results suggested that Ginkgo Plus could relieve the hypoxic pulmonary hypertension.

Effects of ginkgolide B on isobaric hypoxic pulmonary hypertension in rats

OBJECTIVE

To evaluate the effects of Ginkgolide B, a specific platelet activating factor (PAF) antagonist, on hypoxia-induced pulmonary hypertension and pulmonary vascular remodeling.

MATERIALS AND METHODS

Forty male Wistar rats were divided into 4 groups, receiving normal saline, Ginkgolide B, isobaric hypoxia and isobaric hypoxia plus Ginkgolide B respectively. Pulmonary hemodynamics were assessed via right heart catheterization. Pulmonary vascular remodeling were examined by a computerized image analyser.

RESULTS

Chronic hypoxia (FiO2 = 0.10, 3 weeks) caused pulmonary hypertension, pulmonary vascular remodeling and right ventricular hypertrophy in rats. Treatment with Ginkgolide B reduced the extent of pulmonary hypertension, pulmonary vascular remodeling and right ventricular hypertrophy induced by hypoxic exposure.

CONCLUSIONS

The results suggest that PAF participates in the process of chronic hypoxic pulmonary hypertension and pulmonary vascular remodeling, and PAF antagonist could be a potentially useful agent for preventing hypoxic pulmonary hypertension.

[An observation on calcium ion overloaded injury and the effect of calcium channel blocker in rabbit retina under acute ocular hypertension]

OBJECTIVE

In order to observe the retinal injury by Ca+2 overload under ocular hypertension and the effect of verapamil treatment.

METHODS

Atomic absorption spectrophotometry and phosphate pyroantemonate (PPA) means were used to observe the changes of rabbit retinal Ca+2 content and the therapeutic effects of verapamil under this situation.

RESULTS

In the ocular hypertensive group, Ca+2 increased from the moment of intraocular pressure elevation, and with prolongation of time, it tended to increase steadily. In comparison with the control group, there were significant differences (P < 0.01). PPA showed that the longer the time, the more obvious swollen the mitochondria and much more calcium deposition in the mitochondria. In the group of rabbits with ocular hypertension having taken verapamil treatment, the Ca+2 content was markedly lower, the changes of mitochondria milder and the Ca+2 deposition in mitochondria less than that of the ocular hypertension group without treatment.

CONCLUSION

Calcium-overload may be one of the reasons of retinal injury under ocular hypertension, while calcium-blocker may alleviate this injury.

[The role of platelet activating factor in chronic pulmonary hypertension]

To investigate the chronic effects of platelet activating factor (PAF) on pulmonary circulation, we administered PAF to 15 male Wistar rats in low doses by intraperitoneal injection for 28 days. The results showed that after PAF treatment the mean pulmonary arterial pressure increased by 1.17 kPa, the pulmonary vascular resistance increased by 2409.3 kPa.s/L, the cardiac output decreased by 9.1 ml/min and the ratio of right ventricular weight to left ventricular plus septal weights increased by 0.1, compared with control. Histologic sections of the lungs were examined under light microscope equipped with a computerized image analyser. The wall of pulmonary arterioles was thickened; the percent of vascular wall thickness/vascular external diameter and percent of vascular wall area/total vascular area were increased in the PAF group (P < 0.05). These suggest that PAF may play an important role in the pathogenesis of chronic pulmonary hypertension.

Expression of recombinant alpha Ains-crystallin and not alpha A-crystallin inhibits bacterial growth

alpha A-Crystallin and alpha Ains-crystallin are derived from the alpha A-crystallin gene via alternative splicing. They are identical except for the presence of a polypeptide, 23 amino acids long, encoded by the 'insert' exon. Evolutionary logic would suggest that the insertion of a 23 amino acid peptide in the middle of alpha A-crystallin, a protein evolving more slowly than either histone H1, cytochrome c or hemoglobin, would lead to appreciable structural and functional changes. However, based on physico-chemical studies, it is presently believed that alpha A-crystallin and alpha Ains-crystallin are functionally equivalent and that the presence of the 'insert' peptide in alpha Ains-crystallin is inconsequential. We report here that the independent expression of recombinant alpha Ains-crystallin, and not alpha A-crystallin, inhibits growth of the bacterial host. These observations were confirmed in coexpression experiments, wherein both the proteins were expressed in the same cell. Interestingly, growth inhibition is reversible. Importantly, the data demonstrate that it is catalytic amounts and not the gross accumulation of alpha Ains-crystallin which causes growth inhibition. Given the prior knowledge that alpha A-crystallin and alpha Ains-crystallin differ by a peptide of 23 amino acids, these data suggest that the "insert peptide' in alpha Ains-crystallin imparts properties on this protein that are different from alpha A-crystallin.

Split fractures of the lateral tibial plateau: evaluation of three fixation methods

A laboratory study was performed to compare the stability and ultimate strength of three standard fixation techniques for split-type lateral tibial plateau fractures. The three methods of fixation were (a) three 6.5-mm cancellous lag screws with washers; (b) two 6.5-mm cancellous lag screws with washers and an additional antiglide 4.5-mm cortical screw with washer; and (c) six-hole L-shaped buttress plate. Twelve pairs of embalmed mildly osteopenic lower extremities were used. Simulated split-type lateral tibial plateau fractures were created, reduced, and then instrumented in a matched pair design. The instrumented specimens were axially loaded to determine resistance to displacement, cyclically loaded to 10,000 cycles to determine dynamic stability, and then loaded to failure. There were no statistically significant differences found between resistance to displacement or failure strength as a function of either fragment size or sample bone density. On the basis of biomechanical stability, there appears to be no difference between the three fixation techniques tested. The results of this study suggest that use of an antiglide screw or buttress plate does not offer an advantage over lag screw fixation alone for the treatment of split type lateral tibial plateau fractures.

[The level of platelet activating factor in blood of rats with hypoxic pulmonary hypertension]

Because hypoxia is a known predisposing factor for pulmonary hypertension, we investigated the effects of hypoxia and platelet activating factor (PAF) on the development of pulmonary hypertension in rats. Male Wistar rats were made hypoxic by placing them in a isobaric hypoxic chambar (O2 = 10%) for 3 weeks; the rats developed pulmonary hypertension and right ventricular hypertrophy. We found that PAF level in blood of rats were significantly elevated at 2-3 weeks of hypoxia (280.8 +/- 119.7 ng/ml and 324.2 +/- 67.6 ng/ml vs 148.3 +/- 60.2 ng/ml). Therefore, we conclude that PAF plays a central role in mediating hypoxia-induced pulmonary hypertension.

Preconception health care for the primary care practitioner

There will always be birth defects and pregnancy complications due to factors beyond our control. However, we are rapidly discovering many interventions women can use to optimize their chances of having a healthy pregnancy and baby. Most of these, such as immunization and normalization of a diabetic woman's glycosylated hemoglobin level, are most effective when begun before conception. Since the discovery of the congenital rubella syndrome in 1941, there has been a steady accumulation of information on the prevention of birth defects through preconception health. In just the last few years, we have learned that folic acid can decrease neural tube defects, angiotensin converting enzyme inhibitors are teratogenic, and zidovudine can decrease the vertical transmission rate of human immunodeficiency virus. The Varivax vaccine released last year is expected to decrease the perinatal morbidity from varicella. By using the time before conception, we may be able to fully maximize the benefits of good nutrition, exercise, medical screening, and avoidance of environmental toxins.

[Protective and treated effects of L-arginine on hypoxia-induced pulmonary hypertension in rats]

The protective and treated effects of L-Arginine on isobaric hypoxia-induced pulmonary hypertension were studied in rats. It was found that L-Arginine significantly inhibits hypoxic pulmonary hypertension and right ventricular hypertrophy. The mean pulmonary arterial pressure (mPAP) was 3.58 +/- 0.06 kPa and right ventricle/(left ventricle plus septum) ratio [RV/(LV+S)] was 0.34 +/- 0.01 in rats exposed to hypoxia (FiO2 = 0.10 +/- 0.05) for 3 weeks. The mPAP was 2.61 +/- 0.09 kPa and RV/(LV+S) was 0.26 +/- 0.01 in rats pretreated with L-Arginine [200mg/(kg.d)]i there is significant difference between the two groups. We also found that L-Arginine (300mg/kg) can decrease mPAP in rats with hypoxic pulmonary hypertension. The results suggest that L-Arginine might have significant protential for protection and treatment of hypoxic pulmonary hypertension.

Radiology uses of the Internet

The Internet promises to be an essential resource for radiology administrators. In addition to offering remarkable access to colleagues all over the world, the Internet offers specialized information resources for radiology, many of which are described in this article. The Internet is many networks that communicate with each other and whose general purpose is to share information. Although there are several consortium organizations that support and regulate it, no single body or organization "owns" the Internet. Many employees and students at large teaching centers already have access to the Internet through their institution's connection. Individuals and small institutions can contract with independent service providers for Internet access. Internet functions covered in this article include: e-mail, listservs, newsgroups, file transfer protocols, Gopher, and the World Wide Web. The rapid pace of information exchange is making the world of radiology smaller and more intimate. Communication and knowledge are becoming so accessible that individuals are privy to the most minute happenings in the industry. Sharing information on the Internet will benefit not only individual users and the industry, but also patients.

Regulation and immunolocalization of acyl-coenzyme A: cholesterol acyltransferase in mammalian cells as studied with specific antibodies

Acyl-coenzyme A:cholesterol acyltransferase (ACAT) catalyzes the formation of intracellular cholesterol esters in various tissues. We recently reported the cloning and expression of human macrophage ACAT cDNA. In the current study, we report the production of specific polyclonal antibodies against ACAT by immunizing rabbits with the recombinant fusion protein composed of glutathione S-transferase and the first 131 amino acids of ACAT protein. Immunoblot analysis showed that the antibodies cross-reacted with a 50-kDa protein band from a variety of human cell lines. These antibodies immunodepleted more than 90% of detergent-solubilized ACAT activities from six different human cell types, demonstrating that the 50-kDa protein is the major ACAT catalytic component in these cells. In multiple human tissues examined, the antibodies recognized protein bands with various molecular weights. These antibodies also cross-reacted with the ACAT protein in Chinese hamster ovary cells. Immunoblot analysis showed that the ACAT protein contents in human fibroblast cells, HepG2 cells, or Chinese hamster ovary cells were not affected by sterol in the medium, demonstrating that the main mechanism for sterol-dependent regulation of ACAT activity in these cells is not change in ACAT protein content. As revealed by indirect immunofluorescent microscopy, the ACAT protein in tissue culture cells was located in the endoplasmic reticulum. This finding, along with earlier studies, suggests that cholesterol concentration in the endoplasmic reticulum may be the major determinant for regulating ACAT activity in the intact cells.

[Effect of tetrandrine on pulmonary hypertension induced by monocrotaline in rats]

The effects of Tetrandrine (Tet) on intraacinous pulmonary arteries (IAPA) and bemodynamics were studied by means of a rat pulmonary hypertension model induced by monocrotaline. The results showed that Tet could reduce the contractive pressure of pulmonary artery, right ventricle and right atrium of heart by 28.0%, 28.3%, and 31.5% respectively. It could also decrease the vascular degeneration of endoepithelial cells of IAPA, the endoepithelial subcavity, the collagens of medial membrane and the numbers of smooth muscles of IAPA.

[Effects of ginkgolide B on isobaric hypoxic pulmonary hypertension in rats]

We examined the effects of ginkgolide B (BN52021), a specific platelet activating factor (PAF) antagonist, on hypoxia-induced pulmonary hypertension and pulmonary vascular remodeling. Chronic hypoxia can cause pulmonary hypertension and pulmonary vascular remodeling in rats. Treated with BN52021, the rat's pulmonary hypertension, pulmonary vascular remodeling and right ventricular hypertrophy at 3 weeks of hypoxic exposure (FiO2 = 0,10) could be reduced. The results suggest that PAF contributes to the development of chronic hypoxic pulmonary hypertension and pulmonary vascular remodeling, and PAF antagonist may be an useful agent for preventing hypoxic pulmonary hypertension.

Coagulopathies in patients after transurethral resection of the prostate: spinal versus general anesthesia

This prospective, randomized study evaluated the effects of spinal versus general anesthetic technique on perioperative blood loss and the development of postoperative coagulopathies in 50 patients undergoing transurethral resection of the prostate (TURP). Preoperative hematologic measurements included hemoglobin, platelet count, electrolytes, prothrombin time, partial thromboplastin time, fibrinogen, factor V, plasminogen, antithrombin III, and fibrinogen degradation product (FDP) levels. All hematologic blood samples wre repeated postoperatively at 1, 6, and 24 h. Intraoperative blood loss was not significantly different between the spinal and general anesthesia groups. The total blood loss after TURP was significantly correlated (r = 0.76; P < 0.0001) with the prostatic tissue weight. When the tissue weight resected exceeded 35 g, blood loss was in excess of the linear correlation shown with the weight of resected prostatic tissue. Platelet count decreased and prothrombin time increased in the spinal group at all postoperative time intervals compared to preoperative value (P < 0.05). There was no significant difference in measured coagulation variables (fibrinogen, factor V, plasminogen, antithrombin III, and FDP) between the spinal and general anesthesia groups, but there were significant decreases in postoperative fibrinogen and Factor V levels compared to preoperative values in both spinal and general anesthesia groups. Three patients (6%) had increased FDP levels 1 h postoperatively. The prostatic tissue weight and the surgical duration was significantly higher in these patients. We conclude that perioperative blood loss in TURP patients is not affected by the anesthetic technique. However, 6% of TURP patients developed subclinical intravascular coagulopathies which correlated with mass of resected prostate tissue.

[Distribution of platelet activating factor in the pulmonary tissues of normal rats]

Platelet activating factor (PAF) is a biologically active phospholipid with a broad range of cellular targets and respective responses. Because lung homogenates obtained from normal rats contain measurable levels of PAF, it may be involved in both pathological and physiological processes of lung. In this study, we have searched for the distribution of PAF in the rat lungs by immunohistochemistry. We demonstrated that PAF immunoreactivity is present on pulmonary arterial and alveolar walls. The results showed that PAF are located in pulmonary arterial and alveolar wall under normal condition, and that PAF may play a role in maintaining pulmonary physiological process.

[The delayed traumatic intracerebral haematomas]

The results of CT observation of 378 inpatients with head injury were reported. 46 delayed traumatic intracerebral haematomas (DTICH) patients were found to have 71 haematomas. The incidence of DTICH was 12.2%. 80.7% of DTICH patients were noted 48 hours after injury. Most of them were young and middle aged persons. The places of baematomas were at the injured zones. The intracranial pressure continous monitor is useful to judge the DTICH during the early stage. Surgical operation is proposed for the patients with many haematomas and displaced central tissue. The haematomas should be cleansed for the frequently occurring haematoma patients. The death rate of the example was 17.4%, which was lower than 44%-71% reported elsewhere.

[Acute effect of milrinone on pulmonary hemodynamics in patients with hypoxic pulmonary hypertension]

Milrinone is a phosphodiesterase inhibitor that has vasorelaxant activity. The authors studied its effect on pulmonary haemodynamics in 12 patients with hypoxic pulmonary hypertension. After treatment with milrinone, mean pulmonary arterial pressure (from 4.61 +/- 1.41 kPa to 3.36 +/- 1.20 kPa, 1kPa = 7.5mmHg) and pulmonary vascular resistance (from 557.56 +/- 167.70 dyne.sec.cm-5 to 392.60 +/- 133. 81 dyne.sec.cm-5) decreased (P < 0.05), while cardiac output increased (from 5.11 +/- 1.62 L/min to 5.62 +/- 1.66 L/min) (P > 0.05). The systemic blood pressure (from 11.50 +/- 1.63 kPa to 10.71 +/- 1.83 kPa) and systemic vascular resistance (from 1476.64 +/- 531.52 dyne.sec.cm-5 to 1,236.49 +/- 410.18 dyne.sec.cm-5) also decreased (P > 0.05). but there was no change in arterial oxygen saturation (SaO2). The incidence of side effects were low, 4 patients developed tackycardia, and 2 patients developed ventricular premature beats. It is therefore, shown that milrinone is a potent pulmonary vasodilator.

[Acute effects of platelet activating factor on the pulmonary circulation in rats]

To investigate the acute effects of platelet activating factor (PAF) on pulmonary circulation and cardiovascular function in rats, twenty anesthetized Wistar rats were given 100-800 ng/kg PAF by bolus intrapulmonary artery infusion. Mean pulmonary artery pressure (mPAP), mean systemic artery pressure (mSAP) and cardiac output (CO) were measured before and after administration. The results showed that PAF infusion caused: a rise in mPAP from 2.11 +/- 0.20 kPa to 2.65 +/- 0.11 kPa (100 ng/kg, P > 0.05), from 2.32 +/- 0.25 kPa to 2.85 +/- 0.24 kPa (200 ng/kg, P < 0.05) and from 2.11 +/- 0.33 kPa to 3.01 +/- 0.45 kPa (400 ng/kg, P < 0.05)p; a down in mSAP from 16.0 +/- 2.11 kPa to 9.1 +/- 2.39 kPa (100 ng/kg, P < 0.05); from 16.3 +/- 1.38 kPa to 7.0 +/- 0.57 kPa (200 ng/kg, P < 0.05) and from 16.4 +/- 2.56 kPa to 6.3 +/- 0.89 kPa (400 ng/kg, P < 0.05); and a down in CO from 48.1 +/- 2.16 ml/min to 30.8 +/- 3.27 ml/min (100 ng/kg, P < 0.05), from 47.8 +/- 2.12 ml/min to 25.6 +/- 2.86 ml/min (200 ng/kg, P < 0.05) and from 48.3 +/- 2.24 ml/min to 20.0 +/- 2.39 ml/min (400 ng/kg, P < 0.05). These findings suggested that PAF play an important role in the pathophysiologic course of pulmonary hypertension.

Activation of acyl-coenzyme A:cholesterol acyltransferase by cholesterol or by oxysterol in a cell-free system

Acyl-coenzyme A:cholesterol acyltransferase (ACAT) is an intracellular enzyme that catalyzes the conjugation of long chain fatty acid and cholesterol to form cholesteryl esters. It is an integral membrane protein located in the endoplasmic reticulum. Experiments performed in intact mammalian cells have shown that the rate of cholesteryl ester synthesis in intact cells, as well as the ACAT activity from cell extracts, are greatly activated by the addition of low density lipoprotein (LDL) or oxygenated sterols such as 25-hydroxycholesterol to the growth medium. However, the molecular mechanism(s) by which sterol(s) stimulate the ACAT activity remains to be elucidated. Recently, our laboratory reported the expression cloning of human ACAT cDNA (Chang, C. C. Y., Huh, H. Y., Cadigan, K. M., and Chang, T. Y. 1993) J. Biol. Chem. 268, 20747-20755). In the current study, we report the expression of human ACAT cDNA in insect Sf9 cells. Uninfected Sf9 cells do not express detectable ACAT-like activity. Infecting these cells with recombinant virus containing ACAT cDNA caused these cells to express high levels of ACAT protein and high levels of ACAT activity when assayed in vitro. The catalytic properties of ACAT expressed in these cells were found to be similar to those found in human tissue culture cells. The combination of high level of ACAT protein expression and the low level of cellular cholesterol content in the infected cells have provided us a novel opportunity to establish a simple cell-free system, whereby stimulation of ACAT by sterols can be readily demonstrated. Using this system, we have shown that cholesterol itself can serve as an ACAT activator in vitro, in addition to its role as an ACAT substrate. The current work provides the experimental basis to hypothesize that, inside mammalian cells, cholesterol itself may serve as a physiological regulator of ACAT.

High density cultivation of a recombinant CD-1 cell line producing prourokinase using a Biosilon microcarrier culture system

CD-1, a genetically-engineered CHO cell line, was cultivated with a Biosilon microcarrier culture system. We successfully cultivated CD-1 cells to a very high density (over 1 x 10(7) cells/ml). Prourokinase was stably secreted at about 180 IU/10(6) cells/24 h. Experiments showed that CD-1 cells growing on Biosilon microcarriers were able to spontaneously release from the microcarriers, then reattach and proliferate on fresh microcarriers. This makes it very easy to scale up production. The microcarriers could be reused several times without affecting adhesion, proliferation and prourokinase secretion. With CM-PECC membrane radial flow chromatography and MPG chromatography, the prourokinase in conditioned medium could be purified to a specific activity of 1 x 10(5) IU/mg of protein. The purification factor was about 600 fold, and approximately 90% of the biological activity was recovered.

[Clinical application of neurovascular island flap in the hand]

From 1962 to 1992, four kinds of neurovascular island flaps of the hand were used for the treatment of skin defects in the hand in 72 cases. Of these flaps, 38 were pulp flaps of the finger, 24 were based on the first dorsal metacarpal artery, 7 were from second dorsal metacarpal artery and 3 were from hypothenar area. All the flaps survived except 1. Postoperative follow-up showed excellent or good results in 94.4%. The indications of the operation, flap design and surgical procedure are described. The anatomical feature, the advantages and disadvantages of the flap are discussed.

Small cell carcinoma of the ovary associated with ins(10;5)(p13;q31q13)

Cytogenetic analysis of a case of small cell carcinoma of the ovary of hypercalcemic type at relapse showed 46,XX,ins(10;5)(p13;q31q13). This cytogenetic abnormality has not been previously reported in ovarian cancer.

Hepatitis delta virus replication in vitro is not affected by interferon-alpha or -gamma despite intact cellular responses to interferon and dsRNA

The hepatitis delta virus (HDV) genome consists of circular ssRNA which has extensive intramolecular complementarity and can form a dsRNA rod-like structure. If such RNA species were to exist in an unmasked form in cells, they would be expected to induce interferon (IFN) expression and activate two IFN-inducible dsRNA-dependent enzymes with anti-viral activity, namely the dsRNA-dependent protein kinase (PKR) and 2',5' oligoadenylate (2',5' A) synthetase. Since the virus replicates to high copy number for prolonged periods in infected cells it is apparently able to evade these antiviral mechanisms. The RNA genome may be masked and fail to induce or activate the antiviral response, or the virus may inhibit such a response. Treatment of a hepatoma cell line, Huh7, and a fibrosarcoma cell line, HT1080, stably transfected with a trimeric HDV cDNA construct, with IFN-alpha or IFN-gamma for up to seven days failed to influence the level of expression of genomic or antigenomic HDV RNA, or delta antigen (Ag). This is consistent with either failure of activation or inhibition of the IFN response. However the induction of several IFN-responsive genes, including PKR, 2',5' A synthetase and class I MHC is normal and cotransfection of a construct expressing delta Ag did not affect expression from an IFN-inducible chloramphenicol acetyltransferase construct. In addition, the activation of PKR is not inhibited in HDV-expressing cells and antiviral assays suggest that the ability of these cells to mount an antiviral response to at least two cytopathic viruses is unaffected. IFN-beta is inducible normally by dsRNA in cells transfected with the delta cDNA trimer. We conclude that HDV replication is not inhibited by IFN-alpha or IFN-gamma, even though the responses of cells expressing HDV RNA and antigen to IFN and dsRNA are intact.

Renal cell carcinoma: correlation of CT findings with nuclear morphologic grading in 100 tumors

The contrast-enhanced preoperative computed tomographic (CT) scans and microscopic slides of 94 patients with 100 surgically resected renal cell carcinomas (RCCs) were retrospectively and independently reviewed in order to correlate the CT imaging findings of RCC with nuclear grading. As nuclear grade increased, RCCs were more likely to be of higher stage and greater size at presentation, and appeared more heterogeneous and less marginated. Of the features analyzed, tumor margination most closely correlated with nuclear grade. Overlap in the CT appearance of individual tumors limited the potential of CT to differentiate RCCs of varying grade. Small, well-marginated, homogeneous tumors, however, were either grade I or II, and were distinguishable from the more aggressive grade III lesions, which generally displayed irregular margins and greater inhomogeneity.

Clinicopathologic study of 16 cases of primary tubal malignancy

Sixteen cases of primary carcinoma of the fallopian tube were diagnosed and treated at Queen Mary Hospital, Hong Kong from July 1972 to June 1992 constituting 0.26% of the total gynecologic malignancies seen during that period. The average age was 61 years and the most common presenting symptom was abnormal vaginal bleeding. Preoperative diagnosis is difficult; in only one case was a diagnosis of malignancy made by cervical smear. An adnexal mass was detected in 13 of the cases (81.3%) either by clinical examination and/or ultrasonography. Therapy consisted of surgical resection, usually followed by various combinations of adjuvant radiation therapy and chemotherapy. The cumulative survival was 62%. In addition to the typical form of adenocarcinoma, one case of squamous cell carcinoma and a case of multifocal endometrioid adenocarcinoma were observed. One case of an apparently usual form of adenocarcinoma recurred as a heterologous malignant mixed Müllerian tumor 2 years after diagnosis. This series further emphasises the wide range of differentiation possible in the Müllerian system and the variety of neoplasms which may arise from it.

Terpenoid glycosides from the roots of Aster tataricus

A new monoterpene glycoside, shionoside C, and a new oleanane-type triterpene glycoside, aster saponin G, were isolated from the roots of Aster tataricus. Their structures were elucidated on the basis of spectral and chemical methods. Shionoside C is L-endo-camphanol-8-3,5-isopropylidene-beta-D- apiofuranosyl-(1-6)-beta-D-glucopyranoside, aster saponin G is 3-O-[O-alpha-L-arabinopyranosyl-(1-6)-beta-D-glucopyranosyl]-2 beta, 3 beta, 16 alpha-trihydroxyolean-12-en-28-oic acid (asterogenic acid) 28-[O-beta-D-xylopyranosyl-(1-4)-alpha-L- rhamnopyranosyl-(1-2)-beta-D-xylopyranosyl]ester.

[The changes in the levels of angiotensins and angiotensin converting enzyme and effects of captopril in patients with hypoxic pulmonary hypertension]

The levels of angiotensin I, II (ATI, II) and angiotensin converting enzyme (ACE) were measured in 28 patients with hypoxic pulmonary hypertension and 23 normal individuals. The effects of captopril were observed in 8 of 28 patients. The results showed that the average level of ATII in the patients was significantly higher than that in normal control (P < 0.05), but the average level of ACE in the patients was significantly lower than that in the controls (P < 0.05). In 8 patients, after the use of captopril, an ACE inhibitor, for two weeks, the levels of ATII, ACE and mean pulmonary arterial pressure (mPAP) were markedly decreased (P < 0.05). But the other 20 patients treated with antibiotics, antiasthmatics, diuretics and oxygen therapy for two weeks did not show any alterations in the levels of ATII, ACE and mPAP.

Cloning and sequencing of the structural region and expression of putative core gene of hepatitis C virus from a British case of chronic sporadic hepatitis

We report the cloning and sequencing of the putative structural region of the hepatitis C virus (HCV) genome (2229 nucleotides) from an isolate derived from a British case of chronic sporadic non-A, non-B hepatitis. The overall sequence shows a higher similarity with one type of HCV, HCV1 (92%), than with HCV2 (80%), is very highly conserved at the 5' end (99%) preceding the long open reading frame, is well conserved also in the putative core region (90 to 97%), but shows marked variation in the putative envelope region, particularly in the envelope 2/non-structural 1 region (70%). The putative core gene was cloned in pJ3 omega under the early simian virus 40 promoter and expressed in human hepatoma cells. A predominantly cytoplasmic 22K polypeptide was expressed which was antigenically reactive with serum from chronically infected HCV patients.

[Determination of traces of gallium in air by oscillographic polarography]

Gallium and its compounds in air collected by millipore filter membrane are leached by 10% HNO3 at room temperature. After being adjusted with ammonia solution to pH8-9, the leachate is filtered and the filtrate is evaporated to dryness on a water bath. The residue is dissolved with 2 ml of 10% HNO3 and then into the solution are added 0.5 ml of 5% hydroxylamine hydrochloride solution, 0.20 ml of 5% sulfosalicyclic acid solution, 0.5 ml of NaF solution (1mg F/ml) and 1 drop of methyl red solution. Let it stand for 5 min after the color of the solution turns orange by addition of 1:1 NH4OH solution. Add 0.20ml of 0.20% cupferron solution, 0.20ml of 0.5% diphenyl-guanidine solution (prepared in 95% ethanol) and 0.5ml of acetic acid-ammonium acetate buffer (pH 7.0). Then add water to make the final volume of the test solution to be 10ml and measure the height of the second derivative polarographic wave at -1.08V (vs.SCE). The sensitivity of the method is 0.005-0.10 microgram/ml, the coefficient of variation 6.8%, recovery 97.8%. Within 0.005-0.10 microgram/ml, the wave height is linear with the concentration of gallium.

Comparison of the central nervous system activity of the aqueous and lipid extract of kava (Piper methysticum)

The central nervous activity of the aqueous extract of kava was examined in mice, and compared to the effect of the lipid-soluble extract. The aqueous extract caused a loss of spontaneous activity without loss of muscle tone. No hypnotic effect was seen, but some analgesia was produced. The anticonvulsant effect against strychnine was very slight and there was no evidence of local anesthetic action. There was a slight anti-apomorphine effect and tetrabenazine-induced ptosis was decreased. The lipid-soluble extract (kava resin) also decreased spontaneous motility, together with a marked reduction of motor control. Hypnosis, determined by loss of righting reflex, was produced, analgesia was marked, and a local anesthetic action evident. Kava resin also decreased apomorphine-induced hyperreactivity and partially reversed tetrabenazine-induced ptosis. Kava resin produces a greater range of pharmacological actions than the aqueous extract, and the latter is orally inactive in mice and rats. The pharmacological effects of kava ingestion appear to be due to the activity of the compounds present in the lipid-soluble fraction.

Ticlopidine in China: comparative study on the effect of two dose levels on bleeding time and platelet function in healthy volunteers

The compared inhibitory effects of two dose levels of ticlopidine (250 and 500 mg/day) on bleeding time and platelet function in Chinese volunteers have been studied in a placebo-controlled study. Ticlopidine exerted several significant effects: namely prolongation of bleeding time, inhibition of ADP-induced platelet aggregation, reduction of the thromboxane B2 synthesis induced by collagen as well as by ADP. The daily dose of 250 mg did not show significantly different effects as compared to the western, usually recommended daily dose of 500 mg. At the daily dose of 500 mg, adverse reactions occurred more frequently than at the daily dose of 250 mg, but no serious side effects necessitating discontinuation of treatment, or abnormalities in hematological and liver function parameters were observed at these two dose levels. In Chinese people, ticlopidine therapy should be administered at a daily dose of 250 mg.

Identification by methane chemical ionization gas chromatography/mass spectrometry of the products obtained by steam distillation and aqueous acid extraction of commercial Piper methysticum

Bornyl cinnamate has been identified as a constituent of kava resin and of the steam distillate of Piper methysticum. 5-Hydroxydihydrokawain was identified in commercial samples of P. methysticum originating from Vanuatu provided an initial aqueous extraction was employed. Commercial preparations, and fresh samples of the root of this plant from Fiji, lacked this compound. Two previously described N-cinnamoyl pyrrolidine alkaloids were also observed along with stigmasterol in kava resin from Fiji and Vanuatu. The products derived from aqueous 2 M hydrochloric acid extraction of P. methysticum were determined from methane chemical ionization gas chromatography/mass spectrometry analysis which identified a series of hydroxylated compounds (15a-d) derived from formal decarbonylation of the parent kava lactones. The products (13a-c) of dehydration of these compounds were also observed. The efficiency of kava resin extraction from plant material by water (the traditional method of preparation of the kava beverage) was typically 5-10% of that recovered by direct extraction with an organic solvent.

[Pyrrolizidine Alkaloids from Emilia sonchifolia.]

The pyrrolizidine alkaloids, senkirkine ( 1) and doronine ( 2) were isolated from the aerial parts of EMILIA SONCHIFOLIA.

Effects of CI-914 in congestive heart failure due to coronary artery disease or idiopathic cardiomyopathy

The hemodynamic effects of CI-914, a phosphodiesterase inhibitor, were studied in 12 patients with left ventricular (LV) dysfunction who were undergoing diagnostic cardiac catheterization. CI-914 was infused intravenously at a rate of 0.8 to 7.0 micrograms/kg/min for 30 to 60 minutes; hemodynamic values were measured every 10 minutes. No effect was seen in the patient receiving 0.8 microgram/kg/min. At infusion rates of 1.2 to 2.4 micrograms/kg/min, cardiac index increased by 14% (p less than 0.025). At infusion rates of 4.5 to 7.0 micrograms/kg/min, cardiac index increased by 21% (n = 8, difference not significant [NS]). Among 4 patients (group B) with an initial pulmonary artery wedge pressure greater than 20 mm Hg and cardiac index less than 2.5 liters/min/m2, cardiac index increased by 50% (p less than 0.001); it did not change among the 4 patients with an initial pulmonary artery wedge pressure of less than 20 mm Hg and cardiac index of more than 2.5 liters/min/m2 (group A). Although systemic vascular resistance decreased in all 8 patients by 26% (p less than 0.01), the reduction was greater in group B (33%, p less than 0.01) than in group A (16%, NS). Peak +dP/dt increased in all 8 patients by 13% (p less than 0.01). Mean stroke work index increased from 29 +/- 15 to 34 +/- 13 g-m/m2; the double product fell from 101 +/- 31 to 91 +/- 23 (NS). In all 12 patients, a linear correlation between peak venous blood concentration and peak effect on cardiac index, systemic vascular resistance and pulmonary artery wedge pressure was observed.(ABSTRACT TRUNCATED AT 250 WORDS)