Prostate biopsy schemes: 3-D visualization-based evaluation

We have developed a prostate needle biopsy visualization system for the evaluation and optimization of biopsy schemes. Three-dimensional (3-D) prostate surface models have been reconstructed from the digitized whole-mount radical prostetactomy specimens with localized cancers. We have conducted evaluation of five major biopsy schemes with a total of 201 3-D prostate models. These are sextant, 10-pattern, 12-pattern, 14-pattern, and the 5-region schemes. The 10- and 12-pattern biopsy schemes had a 99.0% detection rate, while the rate of traditional sextant biopsy scheme was only 72.6%. The 5-region biopsy scheme had a 90.5% detection rate and the 14-pattern, which includes all the biopsies used in the above schemes, added only one additional positive case (99.5%). Our results suggest that biopsy schemes that use laterally placed biopsies based on the five region anatomical model are superior to the routinely used sextant biopsy scheme. Significant correlation is found between the tumor volume and the positive needle core volume for each of these five schemes. The 10-pattern scheme is the best in cancer detection among these five biopsy schemes.

[Effects of defibrinogenase on photochemically induced middle cerebral artery occlusion in stroke-prone renovascular hypertensive rats]

OBJECTIVE

To investigate the effects of intravenous injection of defibrinogenase on dissoliving dissolve thrombus and salvaging cerebral infarction in stroke-prone renovascular hypertension rats (RHRSP) with middle cerebral artery occlusion(MCAO).

METHODS

The MCAO in RHRSP was induced by administration in photosensitive dye, rose bengal, and irradiation of the main MCA with a focus laser beam. The thrombus in MCA and cerebral infarction were examined microscopically in HE stained sections. Infarction size was determined in triphenyltetrazolium chloride stained sections. Defibrinogenase was injected intravenously at 3, 6, 9, 12 hours and 3, 7 days after MCAO, meanwhile the control group received normal saline. All rats were killed at 72 hours and evaluated by pathological methods after treatment.

RESULTS

In the treatment group, the thrombi were dissolved totally at 3 hours after MCAO, 75% at 6 hours, 13% at 9 hours. Defibrinogenase failed to dissolve thrombus beyond 12 hours after MCAO, just as control group. In comparison with the control group, defibrinogenase significantly reduced infarction size. There was no evidence of hemorrhage.

CONCLUSIONS

Defibrinogenase can reduce infarction size and dissolve thrombus in 6 hours after MCAO without the side effect of hemorrhage.

Distinction among eight opiate drugs in urine by gas chromatography-mass spectrometry

Opiates are commonly abused substances, and forensic urine drug-testing for them requires gas chromatographic-mass spectrometric (GC-MS) confirmation. There are also medical reasons to test urine for opiates, and confirmation procedures other than GC-MS are often used for medical drug-testing. A thin-layer chromatographic (TLC) method distinguishes morphine, acetylmorphine, hydromorphone, oxymorphone, codeine, dihydrocodeine, hydrocodone, and oxycodone in clinical specimens. In certain clinical circumstances, GC-MS confirmation is requested for opiates identified by TLC, but, to our knowledge, no previous report examines all of the above opiates in a single GC-MS procedure. We find that they can be distinguished by GC-MS analyses of trimethylsilyl (TMS) ether derivatives, and identities of 6-keto opiates can be further confirmed by GC-MS analysis of methoxime (MO)-TMS derivatives. Inclusion of deuterium-labeled internal standards permits identification of the opiates in urine at concentrations below the TLC cutoff level of 600 ng/ml, and the GC-MS assay is linear over a concentration range that spans that level. This GC-MS procedure has proved useful as a third-stage identification step in a medical drug-testing sequence involving prior immunoassay and TLC.

Ca(2+)-ATPase activity and lens lipid composition in reconstituted systems

Lens lipid composition and lipid hydrocarbon chain structure change with age, region and cataract. Since the lens Ca(2+)-ATPase pump is important to the maintenance of calcium homeostasis and lens clarity, muscle sarcoplasmic reticulum Ca(2+)-ATPase was reconstituted with bovine lens lipids and dihydrosphingomyelin, the rare and major phospholipid of the human lens. Ca(2+)-ATPase activity was found to be about 5 times lower when the pump was reconstituted into dihydrosphingomyelin or lens lipids compared to native sarcoplasmic reticulum lipids. The addition of cholesterol to levels ranging from 13-53 mole%, had no affect on reconstituted Ca(2+)-ATPase activity. Ca(2+)-ATPase activity correlated with the degree of hydrocarbon chain saturation. The greater levels of saturation are a consequence of the high sphingolipid content in the reconstituted systems. These data support the hypothesis that changes in lens lipid composition or structure could affect Ca(2+)-ATPase activity in human lenses. Because the mechanisms governing Ca(2+)-ATPase activity in vivo are much more complex than in these simple reconstituted systems, this study represents an initial step in the elucidation of the relationships of endogenous membrane lipid composition-structure and function.

Early training may exacerbate brain damage after focal brain ischemia in the rat

Early overuse of a lesioned forelimb, induced by immediate immobilization of the intact forelimb after a cortical lesion, has been reported to increase tissue damage and delay functional recovery. To investigate if early training without immobilization of the intact forelimb could increase tissue loss and reduce recovery, the middle cerebral artery was ligated distal to the striatal branches in 25 male spontaneously hypertensive rats. Control rats were housed in standard cages, training rats were transferred to larger cages allowing various activities and received additional special training 1 hour a day starting either 24 hours or 7 days after the ligation. The rats were tested on a rotating pole, in a leg placement test, and in a water maze and they were killed 6 weeks after the ligation. Delayed training resulted in the best overall performance; however, both training groups performed better than standard rats on the rotating pole. The cortical infarct volume was larger in the early training group than in the other two groups (P < .005), possibly related to increased glutamate release and peri-infarct cortical hyperexcitability.

99mTc-MIBI single-photon emission-computed tomography in diagnosis of lung cancer and mediastinal metastasis lymph nodes

AIM

To evaluate the value of technetium-99m-methoxyisobutyl isonitrile (99mTc-MIBI) single-photon emission-computed tomography (SPECT) in diagnosis of lung cancer and in preoperative prediction of mediastinal metastasis lymph nodes.

METHODS

After the chest image of 99mTc-MIBI SPECT, fifty patients (40M, 10F; age 56 a +/- 11 a) diagnosed "lung field shadow" underwent the lung focus and mediastinal lymph nodes resection. As the golden standard, pathologic diagnosis was used to evaluate the role of preoperative 99mTc-MIBI SPECT.

RESULTS

The sensitivity, specificity, and accuracy of 99mTc-MIBI SPECT were 93%, 50%, and 86%, respectively in lung cancer and 81%, 95%, and 88%, respectively in mediastinal metastasis lymph node. The results were also better than those of chest scan with CT.

CONCLUSION

The 99mTc-MIBI SPECT is a useful and noninvasive method for diagnosing lung cancer and predicting mediastinal metastasis lymph nodes, which will guide the surgeon to resect the mediastinal metastasis lymph nodes.

Human chemokine receptors CCR5, CCR3 and CCR2B share common polarity motif in the first extracellular loop with other human G-protein coupled receptors implications for HIV-1 coreceptor function

Chemokine receptors (CRs) are 7-helix membrane proteins from the family of G-protein coupled receptors (GPCRs). A few human CRs act as cofactors for macrophage-tropic (M-tropic) human immunodeficiency virus type-1 (HIV-1) entry into cells, while others do not. In this study, we describe an application of molecular modeling techniques to delineate common molecular determinants that might be related to coreceptor activity, and the use of the data to identify other GPCRs as putative cofactors for M-tropic HIV-1 entry. Subsequently, the results were confirmed by an experimental approach. The sequences of extracellular domains (ECDs) of CRs were employed in a compatibility search against a database of environmental profiles derived for proteins with known spatial structure. The best-scoring sequence-profile alignments obtained for each ECD were compared in pairs to check for common patterns in residue environments, and consensus sequence-profile fits for ECDs were also derived. Similar hydrophobicity motifs were found in the first extracellular loops of the CRs CCR5, CCR3, and CCR2B, and are all used by M-tropic HIV-1 for cell entry. In contrast, other CRs did not reveal common motifs. However, the same environmental pattern was also delineated in the first extracellular loop of some human GPCRs showing either high (group 1) or low (group 2) degree of similarity of their polarity patterns with those in HIV-1 coreceptors. To address the question of whether the delineated molecular determinant plays a critical role in the receptor-virus binding, three of the identified GPCRs, bradykinin receptor (BRB2) and G-protein receptor (GPR)-CY6 from group 1, and GPR8 from group 2, were cloned and transfected into HeLa-CD4 cells, which are nonpermissive to M-tropic HIV-1 infection. We demonstrate that, similar to CCR5, the two selected GPCRs from group 1 were capable of mediating M-tropic HIV-1 entry, whereas GPR8 from group 2 did not serve as HIV-1 coreceptor. The potential biological significance of the identified structural motif shared by the human CCR5, CCR3, CCR2B and other GPCRs is discussed.

Effect of oxidation on Ca2+ -ATPase activity and membrane lipids in lens epithelial microsomes

Membrane oxidation may contribute to cataractogenesis. In our pursuit to understand the etiology of cataracts, we assessed the effect of membrane oxidation products on the activity of the lens epithelium calcium pump. Microsome preparations from bovine lens epithelium were oxidized to varying degrees with a ferrous and ferric ascorbate system to generate hydrogen peroxide and superoxide. Ca2+ -ATPase activity was measured using a colorometric assay. Lipid oxidation was quantified by infrared spectroscopy. Ca2+ -ATPase activity decreased as a function of ascorbate concentration between 0 and 200 microM. The level of Ca2+ -ATPase inhibition was correlated to both the level of lipid oxidation and the degree of lipid hydrocarbon chain order. At 25 degrees C when lipids are more ordered, the Ca2+ -ATPase activity was similar to that observed in the oxidized system measured at 37 degrees C. Glutathione, mercaptoethanol, and iodoacetate were able to reverse the oxidative inhibition of the calcium pump, suggesting that the ascorbate/iron oxidant directly oxidized the protein sulfhydryl moieties. To further probe the mechanism of Ca2+ ATPase inhibition, hydrogen peroxide was used to oxidize muscle sarcoplasmic reticulum Ca2+ -ATPase reconstituted in its native lipid vesicles, egg phosphatidylcholine, and dihydrosphingomyelin, with saturated hydrocarbon chains. In these systems, oxidation inhibited the Ca2+ -ATPase pump by 60-80%. There was no statistical difference between the level of oxidative inhibition and the percentage of dihydrosphingomyelin. Because dihydrosphingomyelin cannot be oxidized, whereas egg phosphatidylcholine (PC) can, and because the percentage of inhibition was the same for reconstituted systems using either lipid, the mechanism of inhibition is likely not via a secondary process involving oxidation-induced lipid structural changes or products of lipid oxidation.

A method for computational combinatorial peptide design of inhibitors of Ras protein

A computational combinatorial approach is proposed for the design of a peptide inhibitor of Ras protein. The procedure involves three steps. First, a 'Multiple Copy Simultaneous Search' identifies the location of specific functional groups on the Ras surface. This search method allowed us to identify an important binding surface consisting of two beta strands (residues 5-8 and 52-56), in addition to the well known Ras effector loop and switch II region. The two beta strands had not previously been reported to be involved in Ras-Raf interaction. Second, after constructing the peptide inhibitor chain based on the location of N-methylacetamide (NMA) minima, functional groups are selected and connected to the main chain Calpha atom. This step generates a number of possible peptides with different sequences on the Ras surface. Third, potential inhibitors are designed based on a sequence alignment of the peptides generated in the second step. This computational approach reproduces the conserved pattern of hydrophobic, hydrophilic and charged amino acids identified from the Ras effectors. The advantages and limitations of this approach are discussed.

A high-density genome scan detects evidence for a bipolar-disorder susceptibility locus on 13q32 and other potential loci on 1q32 and 18p11.2

Bipolar disorder is a severe mental illness characterized by mood swings of elation and depression. Family, twin, and adoption studies suggest a complex genetic etiology that may involve multiple susceptibility genes and an environmental component. To identify chromosomal loci contributing to vulnerability, we have conducted a genome-wide scan on approximately 396 individuals from 22 multiplex pedigrees by using 607 microsatellite markers. Multipoint nonparametric analysis detected the strongest evidence for linkage at 13q32 with a maximal logarithm of odds (lod) score of 3.5 (P = 0. 000028) under a phenotype model that included bipolar I, bipolar II with major depression, schizoaffective disorder, and recurrent unipolar disorder. Suggestive linkage was found on 1q31-q32 (lod = 2. 67; P = 0.00022) and 18p11.2 (lod = 2.32; P = 0.00054). Recent reports have linked schizophrenia to 13q32 and 18p11.2. Our genome scan identified other interesting regions, 7q31 (lod = 2.08; P = 0. 00099) and 22q11-q13 (lod = 2.1; P = 0.00094), and also confirmed reported linkages on 4p16, 12q23-q24, and 21q22. By comprehensive screening of the entire genome, we detected unreported loci for bipolar disorder, found support for proposed linkages, and gained evidence for the overlap of susceptibility regions for bipolar disorder and schizophrenia.

[A comparative study of HRCT and digital subtraction bronchography of bronchiectasis]

OBJECTIVE

To assess the value of HRCT in the diagnosis of bronchiectasis at segmental level.

METHODS

29 cases (522 segments) with bronchiectasis doubted by clinical evaluation were selected and HRCT scan and digital subtraction bronchography (DSB) were performed.

RESULTS

HRCT and DSB showed a good identity in the diagnosis of bronchiectasis. Of 92 segments diagnosed as bronchiectasis in HRCT, 84 were agreed with DSB; Of 430 segments diagnosed as no bronchiectasis by HRCT, 425 were agreed with DSB. Sensitivity of HRCT is 94%, specificity is 98%. The main HRCT findings were cylindric and cystic bronchiectasis.

CONCLUSIONS

HRCT is superior to bronchography for bronchiectasis. It is the first choice of the image diagnostic modalities for the patients in whom bronchiectasis is suspected.

Three-dimensional computer-simulated prostate models: lateral prostate biopsies increase the detection rate of prostate cancer

OBJECTIVES

Urologists routinely use the systematic sextant needle biopsy technique to detect prostate cancer. However, recent evidence suggests that this technique has a significant sampling error. We developed a novel three-dimensional (3D) computer-assisted prostate biopsy simulator based on whole-mounted step-sectioned radical prostatectomy specimens to compare the diagnostic accuracy of various prostate needle biopsy protocols.

METHODS

We obtained digital images of 201 step-sectioned whole-mounted radical prostatectomy specimens. 3D computer simulation software was developed to accurately depict the anatomy of the prostate and all individual tumor foci. Additional peripheral devices were incorporated into the system to perform interactive prostate biopsies. We obtained 18 biopsies of each prostate model to determine the detection rates of various biopsy protocols.

RESULTS

The 10- and 12-pattern biopsy protocols had a 99.0% detection rate; the traditional sextant biopsy protocol rate was only 72.6%. The 5-region biopsy protocol had a 90.5% detection rate and the 14-pattern, which includes all the biopsies used in the patterns above, only added 1 additional positive case (99.5%). Transitional zone and seminal vesicle biopsies did not result in a significantly increased detection rate when added to the patterns above. Only one positive model was obtained when the transitional zone biopsies were added. The lateral sextant pattern had a detection rate of 95.5%, and the 4-pattern lateral biopsy protocol had a 93.5% detection rate.

CONCLUSIONS

Our results suggest that all the biopsy protocols that use laterally placed biopsies based on the 5-region anatomic model are superior to the routinely used sextant prostate biopsy pattern. Lateral biopsies in the mid and apical zones of the gland are the most important.

[The study on the personality factors in patients' satisfaction with their complete dentures]

OBJECTIVE

To find out the relation between personality factors of edentulous patients and the degree of their satisfaction to the complete dentures.

METHODS

Under the condition of controlling quality of complete dentures, 165 subjects were investigated by using the patient denture satisfaction questionnaire and the revised Cattell's 16 personality factors questionnaire after wearing the complete dentures for one and three months.

RESULTS

The personality factors of edentulous patients such as conscientiousness (G factor), shrewdness (N factor) and so on do affect their denture satisfaction in every aspect of the dentures.

CONCLUSION

The oral prosthodontists not only need improving technological quality of prostheses but also need paying attention to patients' psychological characteristics.

Molecular dynamics simulations of the Ras:Raf and Rap:Raf complexes

The protein Raf is an immediate downstream target of Ras in the MAP kinase signalling pathway. The complex of Ras with the Ras-binding domain (RBD) of Raf has been modelled by homology to the (E30D,K31E)-Rap1A:RBD complex, and both have been subjected to multiple molecular dynamics simulations in solution. While both complexes are stable, several rearrangements occur in the Ras:RBD simulations: the RBD loop 100-109 moves closer to Ras, Arg73 in the RBD moves towards Ras to form a salt bridge with Ras-Asp33, and Loop 4 of the Ras switch II region shifts upwards toward the RBD. The Ras:RBD interactions (including the RBD-Arg73 interaction) are consistent with available NMR and mutagenesis data on the Ras: RBD complex in solution. The Ras switch II region does not interact directly with the RBD, although indirect interactions exist through the effector domain and bridging water molecules. No large-scale RBD motion is seen in the Ras:RBD complex, compared to the Rap:RBD complex, to suggest an allosteric activation of Raf by Ras. This may be because the Raf kinase domain (whose structure is unknown) is not included in the model.

Identification of a putative effector protein for rab11 that participates in transferrin recycling

We have identified and cloned the cDNA for a 912-aa protein, rab11BP, that interacts with the GTP-containing active form of rab11, a GTP-binding protein that plays a critical role in receptor recycling. Although rab11BP is primarily cytosolic, a significant fraction colocalizes with rab11 in endosomal membranes of both the sorting and recycling subcompartments. In vitro binding of rab11 to native rab11BP requires partial denaturation of the latter to expose an internal binding site located between residues 334 and 504 that is apparently masked by the C-terminal portion of the protein, which includes six repeats known as WD40 domains. Within the cell, rab11BP must undergo a conformational change in which the rab11-binding site becomes exposed, because when coexpressed with rab11 in transfected cells the two proteins formed abundant complexes in association with membranes. Furthermore, although overexpression of rab11BP did not affect transferrin recycling, overexpression of a truncated form of the protein, rab11BP(1-504), that includes the rab11-binding site but lacks the WD40 domains inhibited recycling as strongly as does a dominant negative rab11 mutant protein that does not bind GTP. Strikingly, the inhibition caused by the truncated rab11BP was prevented completely when the cells also expressed a C-terminally deleted, nonprenylatable form of rab11 that, by itself, has no effect on recycling. We propose that rab11BP is an effector for rab11, whose association with this GTP-binding protein is dependent on the action of another membrane-associated factor that promotes the unmasking of the rab11-binding site in rab11BP.

[Respiratory monitoring and high frequence jet ventilation (HFJV) in the treatment of severe chest injuries]

Twenty-eight patients with severe chest injuries were classified into 3 groups: fractures of rib, hemopneumothorax and lung injured. Their respiratory rate (RR), SpO2 and blood gas were analysed. The results showed that SpO2 and PaO2 in lung-injured group were the lowest and RR was the highest in the 3 groups. After HFJV, there was a significant rise in PaO2 and SpO2 (P < 0.05) and a gradual recovery of respiratory and pulse rates in lung-injured group. The results suggest that respiratory monitoring is important for patients with chest injuries and HFJV may be used as an effective ventilation method for treating patients with severe chest injuries.

[Characteristics of pulmonary function changes in cough variant asthma and chronic asthmatic bronchitis]

To understand with greater clearness the characteristics of pulmonary function changes in patients with cough variant asthma (CVA) and patients with chronic asthmatic bronchitis(CAB), 30 cases of CVA and 25 cases of CAB were examined by pulmonary function test and were compared clinically. The results showed the differences in medical history and some clinical manifestations between the two groups were significant (P < 0.05). The expiratory flow parameters (PEF, MMEF, FEV1) of pulmonary function test in CVA were generally normal; these parameters in CAB group, however, were obviously decreased. The airway challenge test uncovered a 100% positive reaction in CVA patients, but only less than 1/4 of the patients with CAB showed positive reaction. Furthermore, the positive concentration of challenge agents (Mch) required for CVA group was 1/4.7 of the ones for CAB group, and the positive Mch concentrations of the two groups seldom crossed each other. It is concluded that some clinical manifestations of CVA and CAB were significantly different, although many similarities between them do exist; the MEFV curve in pulmonary function test and the airway challenge test can be used to differentiate them well.

Are neuronal markers and neocortical graft-host interface influenced by housing conditions in rats with cortical infarct cavity?

The aim was to study if exposure to an enriched environment influenced graft-host interface and neuronal markers in neocortical grafts implanted in cortical infarct cavities 3 weeks after distal ligation of the middle cerebral artery in adult hypertensive rats. Half the rats were exposed to an enriched environment for 2 h daily 5 days a week starting 1 week after the arterial ligation. The brain was fixed by perfusion 4 weeks postgrafting. The immunoreactivity to glial fibrillary acidic protein, microtubule associated protein 2, and synaptophysin was studied in coronal paraffin-embedded sections. A distinct glial border separated the infarct cavity from the surrounding brain in sham-transplanted rats. Most grafts filled the larger part of the infarct cavity. In 8 of 18 transplants, 4 in each experimental group, part of the transplants protruded through the thin glial membrane that delineated the transplant-host interface into the adjacent host brain tissue. Microtubule associated protein 2 immunostained sections indicated bridging of dendrites in the host-transplant interface. Synaptophysin immunoreactivity was significantly higher in grafts than in contralateral cortex. However, graft morphology and neuronal marker immunoreactivity did not differ between rats housed in standard and activity stimulating cages.

Protein-protein recognition: an experimental and computational study of the R89K mutation in Raf and its effect on Ras binding

Binding of the protein Raf to the active form of Ras promotes activation of the MAP kinase signaling pathway, triggering cell growth and differentiation. Raf/Arg89 in the center of the binding interface plays an important role determining Ras-Raf binding affinity. We have investigated experimentally and computationally the Raf-R89K mutation, which abolishes signaling in vivo. The binding to [gamma-35S]GTP-Ras of a fusion protein between the Raf-binding domain (RBD) of Raf and GST was reduced at least 175-fold by the mutation, corresponding to a standard binding free energy decrease of at least 3.0 kcal/mol. To compute this free energy and obtain insights into the microscopic interactions favoring binding, we performed alchemical simulations of the RBD, both complexed to Ras and free in solution, in which residue 89 is gradually mutated from Arg into Lys. The simulations give a standard binding free energy decrease of 2.9+/-1.9 kcal/mol, in agreement with experiment. The use of numerous runs with three different force fields allows insights into the sources of uncertainty in the free energy and its components. The binding decreases partly because of a 7 kcal/mol higher cost to desolvate Lys upon binding, compared to Arg, due to better solvent interactions with the more concentrated Lys charge in the unbound state. This effect is expected to be general, contributing to the lower propensity of Lys to participate in protein-protein interfaces. Large contributions to the free energy change also arise from electrostatic interactions with groups up to 8 A away, namely residues 37-41 in the conserved effector domain of Ras (including 4 kcal/mol from Ser39 which loses a bifurcated hydrogen bond to Arg89), the conserved Lys84 and Lys87 of Raf, and 2-3 specific water molecules. This analysis will provide insights into the large experimental database of Ras-Raf mutations.

Membrane lipid alpha-crystallin interaction and membrane Ca2+ -ATPase activities

PURPOSE

To determine the effect of alpha-crystallin binding on lens membrane lipid characteristics and the stability of Ca2+ -ATPase activity when challenged with H2O2 or elevated temperatures.

METHODS

Alpha-Crystallin binding to muscle sarcoplasmic reticulum membranes was quantified using a centrifugation protocol. Alpha-Crystallin binding to lens epithelial lipids was measured by a fluorescence energy transfer technique. Lipid phase transition temperature and lipid order was measured using fluorescence spectroscopy. Ca2+ -ATPase activity was measured using classical biochemical assays.

RESULTS

The main phase transition temperatures of multilamellar vesicles composed of sphingomyelin or lipids extracted from bovine lens were 40 degrees C and 20 degrees C, respectively. In the presence of saturating amounts of alpha-crystallin, the phase transition temperature and lipid order of both sphingomyelin and lens lipid membranes remained almost the same as that without alpha-crystallin. The interaction of alpha-crystallin and lipid is likely to be restricted to the membrane surface. The binding of alpha-crystallin did not influence the oxidative or thermal inactivation of the Ca2+ -ATPase pump.

CONCLUSION

Alpha-Crystallin-lens membrane binding does not protect the Ca2+ -ATPase pump from thermal derangement or oxidation by H2O2.

Tyrosine phosphorylation induced by C4 peptide constructs from HIV Gp120

Treatment of HUT78 cells with CD4-binding peptide constructs derived from the C4 domain of HIV-1 gp120 results in autophosphorylation of a src-related kinase, p56lck. This leads to p56lck activation and the subsequent phosphorylation of tyrosine residues in several intracellular proteins. The phosphorylation is specific to the C4 peptides as no new phosphorylation occurs when the cells are treated with control peptides or polymers. The induction of tyrosine phosphorylation by the C4 peptide constructs depends on the capability of the peptide to assume a helical conformation because similar peptide constructs that were not able to form helices did not induce cellular tyrosine phosphorylation.

[Anatomical and clinical studies on the free posterior leg flap pedicled with the lateral popliteal cutaneous artery]

OBJECTIVE

To investigate the feasibility of free transference of the posterior leg flap which is supplied by the lateral popliteal cutaneous artery.

METHODS

Anatomical dissection is performed in twenty-two freshly amputated adult lower extremities.

RESULTS

The discovery rate of the lateral popliteal cutaneous artery is 100%. The vessel is 20.0 +/- 5.7 cm in length with an exterior diameter of 1.28 +/- 0.25 mm at the junction of the popliteal artery. The course of the artery is constant, and it is usually accompanied by the lateral sural cutaneous nerve. Seven operations using this free flap have been performed successfully.

CONCLUSION

The flap is suitable for repairing medium-sized soft tissue defects or for functional reconstruction.

Acute effect of ethanol on lens cation homeostasis

This study examined the effect of ethanol on the calcium homeostasis of the bovine lens. After acute exposure of the whole lens to physiologically related ethanol concentration, the calcium content of the lens cortex increased from 0.345 +/- 0.075 to 0.476 +/- 0.047 micromol/g (p < 0.05). In contrast, other cation levels such as sodium, potassium, and magnesium did not change. In the study of the lens calcium transport, ethanol caused an increase in the calcium permeability of the lens lipid membrane by about 12% at 30 mM ethanol. Ethanol did not alter the calcium pump activity at ethanol concentration up to 400 mM. Above 600 mM ethanol, the calcium pump was almost completely inhibited. It has been suggested that moderate to heavy alcohol consumption is a risk factor for cataracts. This study indicates that acute ethanol exposure can cause a loss in the lens calcium homeostasis, which maybe one of the cellular mechanisms to contribute to the cataract development in the alcoholic individual.

Increased NHE2 expression in rat intestinal epithelium during ontogeny is transcriptionally mediated

We have previously described changes in intestinal brush-border membrane vesicle (BBMV) Na+/H+ exchange activity and characterized Na+/H+ exchanger (NHE3) expression during rat ontogeny. The current studies were designed to investigate developmental changes in NHE2 expression in rat intestine. In previous studies, pH-dependent uptake of Na+ in jejunal BBMV utilizing HOE-694 inhibition demonstrated that NHE2 functional protein levels were lowest in 2-wk-old rats, higher in 3-wk-old and adult rats, and highest in 6-wk-old rats [Collins et al. Am. J. Physiol. 273 (Cell Physiol. 42): C1937-C1946, 1997]. In the current investigation, Northern blot analyses showed that NHE2 mRNA levels in the jejunum were similar in 6-wk-old, adult, and 3-wk-old rats and three- to fivefold lower in 2-wk-old rats. In situ hybridization of 2- and 6-wk-old rat intestine with NHE2-specific probes confirmed Northern blot observations. Polyclonal antibodies were developed against an NHE2-specific peptide from amino acids 652-661. Western blots with NHE2 antiserum showed that the intensity of a specific 90-kDa band was lowest in 2-wk-old animals and four- to sixfold higher in 3- and 6-wk-old and adult animals. Immunohistochemical analysis showed specific staining of NHE2 antiserum to only the apical intestinal membrane. Furthermore, nuclear run-on analyses showed a 1.7-fold higher NHE2 transcription rate in 6-wk-old rats than in 2-wk-old rats. Overall, the current data suggest that increases in NHE2 expression upon weaning are mediated by increased gene transcription.

Plasma leptin concentrations are only transiently increased in nephrectomized rats

Leptin is an adipocyte-secreted hormone that has effects on appetite and energy expenditure. Several studies have shown that end-stage renal disease results in elevated plasma leptin concentrations and that the kidney is responsible for most of leptin elimination in rodents. Leptin metabolism was investigated in rats that underwent unilateral nephrectomy to experimentally limit renal elimination function. Within 4 h of nephrectomy, plasma leptin concentrations increased from 2.9 +/- 0.8 to 5.8 +/- 1.0 & microg/l but thereafter rapidly (<24 h) decreased to prenephrectomy concentrations, despite continued elevated plasma creatinine levels. Sham-operated rats maintained presurgical concentrations of leptin and creatinine throughout the experiment. Kinetic studies of 125I-labeled leptin elimination showed that fractional catabolic rates and half-lives of leptin in circulation were similar at 48 h in nephrectomized and sham-operated rats, suggesting that production of leptin was unchanged after nephrectomy. Excretion of 125I derived from leptin in urine of nephrectomized rats was similar to that of sham-operated rats, and residual radioactivity was increased in the remaining kidneys excised from nephrectomized rats. These results demonstrate that 1) leptin concentrations are quickly restored to presurgical levels in nephrectomized rats, and 2) it is leptin elimination, not leptin production, that compensates to maintain leptin concentrations. Rapid metabolic adaptation of remaining renal tissue may explain the restoration of normal leptin elimination in nephrectomized rats.

Stroke-prone renovascular hypertensive rats

PURPOSE

To summarized the methods for establishment, characteristics of vascular lesions in brain and heart and the application of stroke-prone renovascular hypertensive rats (RHRSP).

DATA SOURCES AND METHODS

Most published original articles about RHRSP in our laboratory were reviewed.

RESULTS

After the renal arteries were constricted bilaterally with ring-shape silver clips, the stroke-prone renovascular hypertensive rats were established. Hypertension was produced in all RHRSP (100%). The peak of blood pressure in RHRSP reached 29.1 +/- 3.0 kPa. The lesions of cerebral arteries and arterioles and the damage of cerebral capillary structure by hypertension were observed in the RHRSP. The incidence of spontaneous stroke was 56.4% within 40 weeks after the renal artery constriction. Left ventricular hypertrophy and small coronary arterial lesions in myocardium were discovered in all RHRSP. Myocardial infarction occurred spontaneously in 41.8% of RHRSP. The animal models have been used for the studies on mechanisms of stroke and myocardial infarction.

CONCLUSIONS

Because the vascular lesions in cerebrum and heart in RHRSP are similar to that in human beings with hypertension, RHRSP can be used in the studies on mechanisms of hypertensive arteriosclerotic stroke and cardiac lesions and on verifying the effects of different medications to complications of hypertension, and the results might be more reliable than that in animal models without hypertension.

Two-kidney, two clip renovascular hypertensive rats can be used as stroke-prone rats

BACKGROUND AND PURPOSE

The cerebrovascular lesions in stroke-prone spontaneously hypertensive rats are not only dependent on high blood pressure but partly related to pressure-independent genetic factors. The aim of the present study was to observe whether spontaneous stroke occurred in renovascular hypertensive rats without a genetic deficiency.

METHODS

The 1-kidney, 1 clip (1k1c); 2-kidney, 1 clip (2k1c); and 2-kidney, 2 clip (2k2c) methods were used to induce hypertension in male Sprague-Dawley rats with a ring-shaped silver clip. Sham-operated rats were used as controls. Blood pressure and neurological symptoms were observed in the rats without any artificial inducement. Brain sections stained with hematoxylin-eosin and phosphotungstic acid-hematoxylin were examined under a microscope to determine stroke foci.

RESULTS

The attack rate of stable hypertension was 100% (55/55) in the 2k2c group, which was significantly higher than that in the 1k1c (23/30, 76.7%) and 2k1c (21/30, 70%) groups (P<0.01). None of the rats in the 2k2c group died of acute renal failure or suffered from diffuse cerebral lesions postoperatively. Forty weeks after renal artery constriction, the incidence of spontaneous stroke in the 2k2c group was 61.8% (34/55), which was significant higher than that in the 1k1c (7/30, 23.3%) and 2k1c (5/30,16.7%) groups (P<0.01). Stroke foci were not observed in normotensive controls.

CONCLUSIONS

We conclude that 2k2c renovascular hypertensive rats with proper renal artery constriction can be used as stroke-prone renovascular hypertensive rats independent of a genetic deficiency.

Specific interaction of conformational polypeptides derived from HIV gp120 with human T lymphocyte CD4 receptor

Specifically cross-linked peptides (peptomers) have been prepared from the repeating sequences of the C4 domains of glycoproteins 120 present in different isolates of human immunodeficiency virus (HIV). In order to investigate if the HIV C4 peptomers could function as gp120 protein, we have used a novel protein-binding assay to examine if and which components of the peptomers could interact with CD4 receptor in vitro. Here, we demonstrate that all the polymeric components of the HIV-1 C4 peptomer could bind to recombinant soluble CD4 protein. A similar result was also obtained with HIV-2 C4 peptomer except that the binding occured only in those of constituents having molecular weights higher than that of trimer. Remarkably, the CD4-binding was demonstrated to be specific to the HIV C4 peptomers as it did not occur with control peptomers such as Poly V3 MN and Poly NINA whose peptide sequences bore no homology to those of the HIV C4 peptomers. Furthermore, consistent with previous findings, no interaction of HIV-1 C4 monomeric peptide (419-436) with CD4 was detected under the same conditions. Since it is known that the HIV C4 peptomers have much higher contents of alpha-helical conformation than those of their monomeric peptides, we conclude that the secondary structure is a pivotal determinant for the successful CD4-binding by the peptomers. Our finding reveals a more defined molecular nature of the gp120-CD4 interaction and may be important for designing HIV vaccines and therapeutics which target the first step in the virus infection.

[Respiratory muscle function and serum enzymology in hyperthyroidism before and after treatment]

To investigate the effect of hyperthyroidism on respiratory muscle function and its possible mechanism, the thyroid function, serum enzymology, serum potassium, pulmonary function and respiratory muscle function were examined in 60 patients with Grave's disease before treatment and 26 patients among them after treatment, and 20 normal subjects as control. T3, T4, and FT4 increased while FVC and PImax, which reflect the respiratory muscle strength, and Pi/PImax, which reflects the reserve capacity of inspiratory muscle, decreased significantly in the 60 patients with Grave's disease, compared with the ones of normal subjects. The comparison of above measurements in the 26 patients between before- and after-treatment showed that respiratory muscle strength increased obviously along with the improvement of throid function. The serum enzymology, potassium and TSH, however, were not abnormal and not changed after treatment. The thyroid functions in 10 patients with hyperthyroid heart disease were not different, compared with the ones of other 50 patients without hyperthyroid heart disease, but their respiratory muscle strength was significantly lower than the ones of latter. The above results suggested that hyperthyroidism could lead to significant decrease of respiratory muscle strength and its reserve capacity, whereas treatment for hyperthyroidism would improve respiratory muscle function, so the measurement of respiratory muscle function in hyperthyroidism cases might be useful in prediction of hyperthyroid heart disease.

Hydrolysis of GTP on rab11 is required for the direct delivery of transferrin from the pericentriolar recycling compartment to the cell surface but not from sorting endosomes

Rab11 is a small GTP-binding protein that in cultured mammalian cells has been shown to be concentrated in the pericentriolar endosomal recycling compartment and to play a key role in passage of the recycling transferrin receptor through that compartment [Ullrich, O., Reinsch, S., Urbé, S., Zerial, M. & Parton, R. G. (1996) J. Cell Biol. 135, 913-924]. To obtain insights into the site(s) of action of rab11 within the recycling pathway, we have now compared the effects on recycling at 37 degreesC of overexpression of wild-type rab11 and various mutant forms of this protein in cells that had been loaded with transferrin at either 37 degreesC or 16 degreesC. We show that incubation at 16 degreesC blocks passage of endocytosed transferrin into the recycling compartment and that, whereas the rab11 dominant negative mutant form (S25N) inhibits transferrin recycling after interiorization at either temperature, the wild-type rab11 and constitutively active mutant (Q70L) have no inhibitory effect on the recycling of molecules that were interiorized at 16 degreesC. This differential inhibitory effect shows that two distinct pathways for recycling are followed by the bulk of the transferrin molecules interiorized at the two different temperatures. The incapacity of the constitutively active form of rab11 (Q70L) to inhibit recycling of molecules interiorized at 16 degreesC is consistent with their recycling taking place directly from sorting endosomes, in a process that does not require hydrolysis of GTP on rab11. The fact that the dominant negative (S25N) form of rab11 inhibits recycling of molecules interiorized at both temperatures indicates that activation of rab11 by GTP is required for exit of transferrin from sorting endosomes, regardless of whether this exit is toward the recycling compartment or directly to the plasma membrane.

[Determination of morphine in compound liquorice tablets by high performance liquid chromatography with SEP-PAK C18 cartridge pretreatment]

An efficient method combining SEP-PAK C18 cartridge solid phase extraction (SPE) with reversed-phase high performance liquid chromatography for the quantitation of morphine in the Compound Liquorice Tablet is presented. The tablets have been used for making expectoration easy and relieving cough for years. The tablet powder (approximately 1 tablet) was added into a stoppered centrifuge tube, and vertically extracted with 5 mL of 0.5% HAc for 5 min. After centrifugation the supernatant was transferred to a beaker and the extraction was repeated twice with 4 mL and then 3 mL of 0.5% HAc. Five millilitres of carbonate buffer (pH 8.9) was added to the combined extracts. A SEP-PAK C18 cartridge was pretreated by passing methanol and distilled water, using a glass syringe. The mixture was applied on it and allowed to flow through. The cartridge was washed first with 5 mL of 10% methanol solution and then the morphine was eluted with 4 mL of 70% methanol solution into a 5 mL volumetric flask and was finally diluted to volume with 70% methanol solution. Analysis was performed on a mu-Bondapak C18 column(300 mm x 4.6 mm i.d., 10 microns) with 0.1 mol/L NaH2PO4-methanol(5:1) as the mobile phase and detection at 286 nm. The average recovery of morphine was (101.2 +/- 1.5)% and RSD was 1.5%. The method is simple, rapid, accurate, and reproducible, and can be used in drug control.

Conformation of the Ras-binding domain of Raf studied by molecular dynamics and free energy simulations

Recognition of Ras by its downstream target Raf is mediated by a Ras-recognition region in the Ras-binding domain (RBD) of Raf. Residues 78-89 in this region occupy two different conformations in the ensemble of NMR solution structures of the RBD: a fully alpha-helical one, and one where 87-90 form a type IV beta-turn. Molecular dynamics simulations of the RBD in solution were performed to explore the stability of these and other possible conformations of both the wild-type RBD and the R89K mutant, which does not bind Ras. The simulations sample a fully helical conformation for residues 78-89 similar to the NMR helical structures, a conformation where 85-89 form a 3(10)-helical turn, and a conformation where 87-90 form a type I beta-turn, whose free energies are all within 0.3 kcal/mol of each other. NOE patterns and H(alpha) chemical shifts from the simulations are in reasonable agreement with experiment. The NMR turn structure is calculated to be 3 kcal/mol higher than the three above conformations. In a simulation with the same implicit solvent model used in the NMR structure generation, the turn conformation relaxes into the fully helical conformation, illustrating possible structural artifacts introduced by the implicit solvent model. With the Raf R89K mutant, simulations sample a fully helical and a turn conformation, the turn being 0.9 kcal/mol more stable. Thus, the mutation affects the population of RBD conformations, and this is expected to affect Ras binding. For example, if the fully helical conformation of residues 78-89 is required for binding, its free energy increase in R89K will increase the binding free energy by about 0.6 kcal/mol.

Ontogeny of basolateral membrane sodium-hydrogen exchange (NHE) activity and mRNA expression of NHE-1 and NHE-4 in rat kidney and jejunum

Na+/H+ exchange (NHE) activity varies with ontogenic state in rat intestinal basolateral membrane vesicles (BLMV). The current investigation sought to determine if these observations are due to differential expression of BLM NHE isoforms, NHE-1 and NHE-4. In rat kidney, BLMV sodium uptake levels were similar in 2, 3 and 6 week rats (13.28+/-0.68, 14.03+/-0.84, and 11.71+/-0.66 nmol Na+/mg protein/30 s, respectively), and lower in adults (5.53+/-0.24) (n=4; p<0.001 between 2 week rats and adults, and between 3 week rats and adults; p<0.01 between 6 week rats and adults). In rat jejunum, BLMV uptake was highest in adults (13.07+/-0.86 nmol Na+/mg protein/30 s), and decreased in 6, 3, and 2 week rats (4.48+/-0.75, 2.94+/-0.68, and 1.59+/-0.58, respectively) (n=4; p<0.001 between all groups and adults). Control immunoblot experiments with NHE-3 antiserum showed that BLMV preps were not contaminated with significant amounts of this brush-border membrane specific protein. Northern blots with isoform-specific probes showed highest renal NHE-1 hybridization intensities in 2 and 3 week rats (11.00+/-0.25 and 12.07+/-0.16 phosphorimage units, respectively), and lower intensities in 6 week and adult animals (4.30+/-0.95, and 4.40+/-1.40, respectively) (n=4; p<0.01 between 2 week animals and 6 week and adult animals, and between 3 week animals and 6 week and adult animals). NHE-1 probes in the intestine showed no hybridization intensity differences between groups: 2 week-7.09+/-1.10, 3 week-5.39+/-0.56, 6 week-8. 24+/-1.57, and adult-8.99+/-2.20 (n=3). NHE-4 specific probes in the kidney showed hybridization intensity levels of 9.22+/-0.35 in 2 week animals, 12.12+/-1.26 in 3 week animals, 5.63+/-0.81 in 6 week animals, and 3.52+/-0.57 in adults (n=4; p<0.05 between 2 week and adults; p<0.01 between 3 week and 6 week animals, and between 3 week and adults). No NHE-4 message was detected in rat jejunum by Northern blot analysis or by reverse transcriptase-PCR. These results suggest that ontogenic NHE activity at the jejunal BLM is not related to differential expression of NHE-1, while NHE activity at the renal BLM may in part be related to differential ontogenic expression of NHE-1 and NHE-4.

Functional and molecular characterization of NHE3 expression during ontogeny in rat jejunal epithelium

Ontogenic changes occur in intestinal brush-border membrane vesicle (BBMV) Na+/H+ exchange activity. The present studies were designed to investigate ontogenic changes in Na+/H+ exchanger (NHE) isoform 3 in rat jejunum. pH-dependent Na+ uptake was assayed in four age groups of rats in the presence of 0, 50, or 800 microM HOE-694, a specific NHE inhibitor with differential sensitivities for NHE2 [inhibition constant (Ki) = 5 microM in PS120 fibroblasts] and NHE3 (Ki = 650 microM). Results showed that NHE2 and NHE3 contribute to basal BBMV uptake at all ages. Uptake levels were highest in 6-wk-old rats, lower in adult rats, and lowest in 2-wk-old (suckling) and 3-wk-old (weanling) rats, NHE3 contribution ranged from 92% at 6 wk of age to 59% at 2 and 3 wk of age. NHE3 inhibition by 800 microM HOE-694 was 38-45%. Statistical analysis showed that HOE-694 had a significant effect at both concentrations at all ages and that differences were present between all ages except 2- and 3-wk rats (at all HOE-694 concentrations). Northern blot analyses of jejunal mucosa showed lowest NHE3 mRNA levels in 2-wk animals and higher levels in all other age groups. Polyclonal antibodies were developed against an NHE3 COOH-terminal fusion protein, and antiserum was characterized with NHE3-transfected PS120 cells and by immunohistochemistry. Western blot analyses showed lowest protein levels in 2-wk animals and higher levels in the other ages. Suckling rats were subcutaneously injected with methylprednisone (MP) for 2 days and killed 1 day later. Northern blot analyses showed a twofold increase in NHE3 mRNA expression with MP treatment. Immunoblot analyses showed a 2.5-fold increase in NHE3 immunoreactive protein levels with MP injection. Overall, these data suggest that NHE3 is regulated during ontogeny and that ontogenic changes are most apparent around the time of weaning. Furthermore, the data suggest that NHE3 is regulated at transcriptional and posttranscriptional levels during mammalian intestinal development.

Whole body leptin kinetics and renal metabolism in vivo

Leptin metabolism was investigated in male Sprague-Dawley rats by use of 125I-labeled leptin plasma kinetic and arteriovenous balance studies. When conscious rats received bolus venous injections of 125I-leptin, intact (precipitable) leptin quickly disappeared from circulation in a biexponential manner during the 2-h experimental period. After substantial delay, most of the injected radioactivity appeared in the urine. The data were described by a two-compartment model, which postulated that plasma leptin exchanged with a nonplasma pool and that all of the tracer cleared from plasma appeared in urine or in a degraded form in plasma. The half-life of leptin was 9.4 +/- 3.0 min, and the leptin production rate was 3.6 +/- 1.2 ng 100 g fat-1.min-1. The left kidney extracted 21 +/- 1.5% of intact arterial 125I-leptin 5 min after femoral venous injection. Endogenous arterial leptin was reduced 21 +/- 8 and 18 +/- 12%, respectively, in simultaneously sampled left and right renal veins. Renal elimination appears to be the major elimination mechanism for leptin in normal rats, and the kinetic studies suggest that uptake of leptin by renal tissue rather than glomerular filtration is the predominant elimination mechanism.

[Measurement and clinical significance of inspiratory drive efficacy in patients with chronic obstructive pulmonary disease]

To study the relationship between VT/P0.1 and the function of inspiratory muscles, we performed the measurement of VT/P0.1 (inspiratory drive efficacy), MIP (maximal inspiratory mouth pressure) and MMIF (maximal midinspiratory flow) in 15 normal subjects and 60 patients with chronic obstructive pulmonary disease(COPD). The results indicated that VT/P0.1 decreased with the deterioration of COPD and it correlated highly and positively with MIP and MMIF. These suggest that VT/P0.1 can reflect the function of inspiratory muscles as well as MIP and MMIF can.

[Determination of plasma drug concentration and bioavailability of indomethacin controlled release capsule by high performance liquid chromatography]

A simple, rapid, sensitive and accurate reversed-phase high performance liquid chromatographic (RP-HPLC) method for the determination of indomethacin in plasma is established. To 1 mL of plasma were added 200 microL of amobarbitone solution (internal standard; 1 g/L), 100 microL of phosphate buffer solution (pH 7.0), 100-150 mg of sodium chloride and 2.5 mL of ethyl acetate. The mixture was vortex-mixed for 10 min and centrifuged at 3000 r/min for 5 min. The organic layer was evaporated to dryness at 50 degrees C on water-bath and the residue was dissolved in methanol (100 microL). A 20 microL portion of the resulting solution was analysed by HPLC on a column (25 cm x 4.6 mm) of micro-Bondapak C18 (10 microm) with 76% methanol in 0.035 mol/L phosphoric acid (pH 5.5) aq-solution as mobile phase (1 mL/min) and UV detection at 260 nm. The column temperature was 30 degrees C. Within the range of 0.125-50 mg/L of indomethacin there was a good linearity (r = 0.9996). The mean recovery of indomethacin was 100.4%. The detectable limit was 62.5 microg/L (S/N = 3:1). The within day and day-to-day RSD were less than 5% at three drug levels. This method has been used to determine plasma drug concentration and bioavailability of indomethacin controlled release capsule for healthy volunteers.

Differences in molar absorptivity of 4-NP with the reaction solution and apparatus affect ALP measurement

We examined the differences in molar absorptivity of 4-NP obtained using different kits for ALP measurement and different instruments. The apparent molar absorptivity of 4-NP in the same reaction solution determined by six different instruments was 15.98, 16.72, 16.06, 17.00, 16.27, 17.62 and that using four different reaction solution kits for ALP with the same instrument was 16.90, 17.38, 17.72, 16.11. We measured ALP in three serum samples with six instruments using the same kit and in twelve serum samples with the same instrument using four kits. ALP activities measured using the same molar absorptivity value differed with the instrument(p < 0.01). However, those measured using the apparent molar absorptivity value for each instrument revealed no significant differences(p > 0.05). In conclusion, we suggest that standard material should be contained in each kit for enzyme measurement and the apparent epsilon for each kit and instrument should be obtained to minimize the systematic error caused by using the same epsilon in different laboratories.

Calcium ATPase activity and membrane structure in clear and cataractous human lenses

PURPOSE

Maintenance of calcium homeostasis is imperative for the clarity of the lens. Ca(2+)-ATPase is essential for the removal of cytosolic calcium, either across the plasma membrane or through intracellular organelles such as the endoplasmic reticulum. In this study, membranes prepared from clear lens epithelium were compared to membranes prepared from cataractous lens epithelium.

METHODS

Human lens membranes were prepared by a protocol utilizing homogenization and centrifugation. Ca(2+)-ATPase activity was measured biochemically using Gamma-32P labeled ATP. Lipid order was measured using infrared and Raman spectroscopy.

RESULTS

Ca(2+)-ATPase activity was similar in membranes prepared from cataractous lenses that were classified as nuclear subcapsular, nuclear and brunescent cataracts. Ca(2+)-ATPase activity was approximately 50% less in membranes prepared from cataractous lenses in comparison to clear lenses. Because clear lenses from Indian donors was unavailable, clear human lenses were used as a qualitative control for the measurement for Ca(2+)-ATPase activity. Lipid order was measured in lens fibers from cataractous and clear lenses from the United States donors. Lipid order increased from 55% in the hydrocarbon chains from clear lens fibers to 84% in cataractous lens fibers.

CONCLUSIONS

These findings support the hypothesis that membranes are deranged in cataractous tissue, which should lead to altered levels of calcium.

[Effect of methylphenidatum on inspiratory muscles function in patients with chronic obstructive pulmonary disease and its mechanism]

To have a better understanding of the effect of methylphenidatum on inspiratory muscles function, we studied the respiratory force parameters of 70 patients with chronic obstructive pulmonary disease by intravenous infusion methylphenidatum in a randomized controlled clinical trial. The indices of respiratory force parameter included maximal inspiratory mouth pressure (MIP), maximal midinspiratory flow (MMIF), forced inspiratory capacity (FIC), maximal works of inspiration (Wimax) and airway occlusion pressure (P0.1), etc. Aminophylline and Nikethamidi were chosen as controls. The results showed that MIP, MMIF, FIC, Wimax, P0.1 and minute ventilation (Vr) were significantly increased after administration of methylphenidatum and aminophylline. There were no significant differences in MIP, MMIF, FIC and Wimax after administration of Nikethamidi, but P0.1 was significantly increased and the increase was higher than that after administration of methylphenidatum and aminophylline groups. We conclude that methylphenidatum can significantly improve the function of inspiratory muscles as aminophylline can do.

Histopathologic and biochemical changes in the muscles affected by distraction osteogenesis of the mandible

Lengthening of the canine mandible using an intraoral distraction device was performed in order to study the effects of distraction on the associated muscles of mastication. Biopsies of the masseter and digastric muscles were taken after lengthening at four different time intervals to assess the temporal changes in the masticatory muscles of 10 dogs. Biopsies of the muscles on the contralateral side also were taken from 6 of these dogs before lengthening to establish a control group. Each biopsy was analyzed histologically and spectophotomerically for RNA, DNA and protein content. The digastric muscle underwent transient atrophy with initiation of distraction but regenerated completely after 48 days of fixation. The masseter muscle was unchanged initially but showed evidence of atrophy only after 20 mm of distraction it continued to exhibit evidence of atrophy during fixation. Protein synthesis was decreased significantly during periods of atrophy in the masseter; no such change was noted in the digastric. Unlike the masseter, the digastric fibers lie in a plane parallel to the vector of distraction. These findings suggest that any muscle affected by skeletal distraction in the same plane or vector (e.g., digastric) adapts with compensatory regeneration and hypertrophy. Moreover, those muscles lying in a different plane (e.g., masseter) show persistent evidence of atrophy with decreased protein synthesis.

Calcium permeability in large unilamellar vesicles prepared from bovine lens cortical lipids

The loss of calcium homeostasis in the lens is thought to play an important role in cataract formation. Although both lens Ca(2+)-ATPase and membrane lipid permeability are essential to calcium homeostasis, membrane permeability has been studied less extensively. In the present study, the calcium permeability of large unilamellar vesicles (LUVs) prepared from bovine lens cortical lipids has been characterized. When a calcium gradient had been established by the addition of CaCl2 to the external medium, calcium influx through the membrane was monitored by calcium concentration sensitive changes in Fura-2 fluorescence as a function of time. The calcium permeability coefficient, P, was 4.46 x 10(-13) cm s-1 at 37 degrees C. This value was about 4 fold higher than that for LUVs prepared from egg phosphatidylcholine and many times higher than that for LUVs prepared from sphingomyelin. These results provide a basis for future studies of factors that influence the permeability of lens cell membranes to calcium.

[Cetirizine improves the resistance of airway and pulmonary function in patients with asthma]

The objective of this study was to investigate the possible anti-asthma role of Cetirizine. Forty asthmatics were randomly divided into two groups. The experimental group had 30 patients. Among them were 10 patients with simple asthma, 5 patients complicated by mild emphysema, 6 patients complicated by moderate emphysema and 9 patients complicated by severe emphysema. Vit-C (control) group had 10 cases, including 2 cases of simple asthma, 6 cases complicated by mild emphysema and 2 cases complicated by moderate emphysema. All patients had a single oral dose of 5 mg Cetirizine or 0.1 g Vit-C blindly. Before and 0.5, 1 hour after their medicines, the resistance of airway (Raw), sGaw and MEFV were examined in all patients on 6200 Plethysmograph. The measured values showed a significant improvement of Raw and sGaw after administration of Cetirizine. In half an hour after Cetirizine, the Raw decreased by 20.408%, and sGaw increased by 28.249%. In one hour after Cetirizine, Raw further decreased by 24.34% and sGaw increased by 41.153% (P < 0.001). The FVC in MEFV increased by 4.96% (P < 0.02) in one hour after Cetirizine, but other parameters in MEFV curve (PEF, FEV1, MMEF) had no significant changes. All parameters in control group had no significant changes (P > 0.05). The results indicate that Cetirizine could decrease Raw in asthmatics, improve their lung ventilatory function. Cetirizine is a new H-receptor antagonist usually used as anti-inflammatory and allergy suppression medication. It is shown that Cetirizine is a promising anti-asthma agent in treating bronchial asthma.

[The combined subdermal vascular network skin flaps of the abdominal wall for the repair of soft tissue defects on the dorsum of hand]

Successful reconstructive surgery was performed on ten patients with skin and soft tissue defects on the dorsum of their hand and fingers using combined subdermal vascular network flaps of the abdominal wall. The pedicle of the flap was divided on 7-10 postoperative day when wound was closed, finger and web reconstruction were completed at the same stage. The operative results were satisfactory. The authors discussed the technique of the method, the blood supply of the flap, the principle of the design and the advantages of the operation.

[Value of measuring resistance of airway for diagnosis of asthma]

Resistance of airway (Raw), sGaw and Maximal expiratory flowvolume curve (MEFV) were measured in 35 normal subject, 43 patients with remission asthma and 100 patients with remission chronic bronchitis (some complicated by obstructive emphysema). The measured values showed that in simple asthma Raw was significantly higher than that in normal subject and in patients with chronic obstructive bronchitis (COB), but MEFV was in normal range. In chronic bronchitis the value of Raw was higher than that in normal subject, but lower than that in asthma (0.05 > P > 0.02); however the FEV1, MMEF, V75 in the curve of MEFV were significantly decreased at the stage of COB, with the most remarkable decrease in MMEF. The results suggest that Raw is a sentitive test for diagnosis of simple asthma, in addition to MEFV measurement; it may be helpful for differential diagnosis of simple asthma and COB and may has potential value for clinical practice.