[The expression of tyrosine-kinase receptor flk-1 and hypoxic pulmonary vascular remodeling in the lung of rats exposed to hypoxia]

OBJECTIVE

To assess the role of tyrosine-kinase receptor flk-1 in the development of hypoxic pulmonary vascular remodeling.

METHODS

We divided 20 male Wistar rats into two groups(control vs hypoxia) and exposed them to normoxic condition and isobaric hypoxia for 3 weeks respectively. The pulmonary artery pressure was measured by right cardiac catheterization. The expression of flk-1 in lung tissues was measured by immunohistochemical staining. Histologic sections of the lungs were examined by a computerized image analyser.

RESULTS

In hypoxic rats, the pulmonary artery pressure was significantly raised to a higher level, P < 0.01; the cell number of vascular wall was significantly increased. The results also demonstrated that chronic hypoxia brought about the significant increment in thickness of wall with narrowing of lumen of pulmonary arterioles, and the increment in the percent of vascular wall thickness/vascular external diameter (WT%) and the percent of vascular wall area/total vascular area (WA%), P < 0.01. The positive staining of flk-1 in the wall of pulmonary arteriole of rats treated with hypoxia was significantly stronger than that of normal rats, P < 0.01. Positive correlations were seen between the increment of expression of flk-1 with WT% and WA% (r = 0.714, 0.738, P < 0.01).

CONCLUSION

Chronic hypoxia can induce an increasing expression of flk-1, and the flk-1 may play an important role in the pathogenesis of hypoxic pulmonary vascular remodeling.

Human acyl-CoA:diacylglycerol acyltransferase is a tetrameric protein

Acyl-CoA:diacylglycerol acyltransferase (DGAT) is an integral membrane enzyme that catalyses the last step of triacylglycerol synthesis from diacylglycerol and acyl-CoA. Here we provide experimental evidence that DGAT is a homotetramer. Although the predicted molecular mass of human DGAT protein is 55 kDa, CHAPS-solubilized recombinant human DGAT was eluted in fractions over 150 kDa on gel-filtration chromatography. Cross-linking of recombinant DGAT in membranes with disuccinimidyl suberate yielded bands corresponding to the dimer (108 kDa) and the tetramer (214 kDa) in SDS/PAGE. Finally, when two differently epitope-tagged forms of DGAT were co-transfected into mammalian cells, they could be co-immunoprecipitated. From a human adipose tissue cDNA library we cloned a cDNA encoding a novel splice variant of DGAT (designated DGATsv) that contained a 77 nt insert of unspliced intron with an in-frame stop codon. This resulted in a truncated form of DGAT that terminated at Arg-387, deleting 101 residues from the C-terminus containing the putative active site. DGATsv was enzymically inactive when transfected in HEK-293E cells but was still able to form dimer and tetramer on cross-linking, indicating that the ability to form tetramers resides in the N-terminal region. When co-expressed in HEK-293E cells, DGATsv did not inhibit the activity of full-length DGAT, suggesting that the subunits of DGAT catalyse triacylglycerol synthesis independently.

[The effect of monocarboxylate transporter gene on the regulation of pHi and growth character in cancer cells]

OBJECTIVE

To study the influence of the first subtype of monocarboxylate transporter (MCT1) gene on pHi regulation, lactate transport and cell growth in tumor cells.

METHODS

(1) With RT-PCR technique, MCT1 cDNA fragment was cloned from human lung cancer cells A549, and the cloned fragment MCT1 was reversely inserted into the vector pLXSN to acquire antisense expression recombinant vector pLXSN-MCT1. (2) pLXSN, pLXSN-MCT1 were respectively introduced into the A549 cells by electroporation. The transfected A549 cell resistant to G418 drug was selected as positive clones and proved by PCR. The changes of intracellular pH and lactate in the transfected A549 cells were detected by spectrophotometric method. Cell growth was studied by cell growth curve.

RESULTS

(1) The cloned fragment was in the length of 640 bp and successfully bound to pLXSN. It was also proved to be the objective one by DNA sequencing. (2) Intracellular pH and lactate were remarkably decreased in the cells transfected pLXSN-MCT1, comparing to A549 cells without transfection (P < 0.001). The growth of A549 cells transfected pLXSN-MCT1 was also inhibited remarkably.

CONCLUSION

MCT1 gene could play an important role in pHi regulation, lactate transport and cell growth in tumor cells.

Mild hypothermia increases Bcl-2 protein expression following global cerebral ischemia

Mild hypothermia protects the brain against experimental ischemia, but the reasons are not well known. We examined whether the protective effects of mild hypothermia could be correlated with alterations in expression of Bcl-2, an anti-apoptotic protein in a rat model of transient global ischemia. Following 10 min of forebrain ischemia, hippocampal neurons were examined 72 h later for survival, expression of Bcl-2 family proteins and apoptosis. Intraischemic mild hypothermia was applied for 3 h (33 degrees C, isch-33) or normal body temperature was maintained (37 degrees C, isch-37). Survival of CA1 neurons was significantly improved in the isch-33 group compared to the isch-37 group (90 vs. 53% survival; P<0.01). The proportion of Bcl-2-positive cells among surviving CA1 neurons in the isch-33 group was increased compared to that of sham and isch-37 groups (P<0.01). Bax expression in CA1 was no different between sham and isch-33 groups, but was significantly decreased in isch-37 (P<0.05). TUNEL staining was positive in many isch-37 CA1 neurons, but absent in isch-33. Utilizing electron microscopy, more cells meeting criteria for apoptosis were observed in the isch-37 than isch-33. These data suggest that mild hypothermia attenuates apoptotic death, and that this protection may be related to increases in Bcl-2.

Corrosion properties of nanocrystalline Co-Cr coatings

Nanocrystalline and conventional Co-Cr (ASTM F75) coatings were prepared by plasma spraying for possible orthopedic implant applications. Scanning electron microscopy and transmission electron microscopy were used to study the macrostructure and microstructure of the resultant sprayed coatings. The corrosion resistance was characterized by an in vitro potentiodynamic anodic polarization technique in a pseudophysiological solution. The nanocrystalline coating has higher porosity, lower corrosion current density, and less localized damage than that of the conventional one, demonstrating better application potential for orthopedic implants. A change in the atomic compositional difference between the grain interior and the grain boundary, the presence of residual strain in the grain interiors, and a change in the repassivation kinetics are discussed as possible explanations for the enhanced corrosion behavior observed.

Aerodynamic adsorption of permeable chemical protective suit

A new laboratory apparatus and method were developed to test the protective ability of a permeable chemical protective suit (PCPS). The key features of this method are using a wind tunnel system and an aerodynamic model that could incorporate the complicated flow pattern around the protective clothing. This method illustrates the process of the PCPS system performance and can provide a system assessment through bench-scale experiments. A new aerodynamic adsorption equation for PCPS breakthrough curve calculation based on an aerodynamic model has been suggested, and the calculated breakthrough curves of benzene vapor on PCPS conform to the experiment curves.

In situ activation of helper T cells in the lung

To better understand the lung and systemic responses of helper T cells mediating memory immunity to Mycobacterium tuberculosis, we used three- and four-color flow cytometry to study the surface phenotype of CD4(+) lymphocytes. Bronchoalveolar lavage (BAL) fluid and peripheral blood (PB) samples were obtained from a total of 25 subjects, including 10 tuberculosis (TB)-infected subjects, 8 purified-protein-derivative-negative subjects, and 7 purified-protein-derivative-positive subjects. In marked contrast to CD4(+) lymphocytes from PB (9% +/- 5% expressing CD45RA and CD29), the majority (55% +/- 16%) of CD4(+) lymphocytes in BAL (ALs) simultaneously expressed CD45RA, a naïve T-cell marker, and CD29, members of the very late activation family. Further evaluation revealed that CD4(+) ALs expressed both CD45RA and CD45RO, a memory T-cell marker. In addition, the proportion of CD4(+) lymphocytes expressing CD69, an early activation marker, was drastically increased in BAL fluid (83% +/- 9%) compared to PB (1% +/- 1%), whereas no significant difference was seen in the expression of CD25, the low-affinity interleukin 2 receptor (34% +/- 15% versus 40% +/- 16%). More importantly, we identified a minor population of CD69(bright) CD25(bright) CD4(+) lymphocytes in BAL (10% +/- 6%) that were consistently absent from PB (1% +/- 1%). Thus, CD4(+) lymphocytes in the lung paradoxically coexpress surface molecules characteristic of naïve and memory helper T cells as well as surface molecules commonly associated with early and late stages of activation. No difference was observed for ALs obtained from TB-infected and uninfected lung segments in this regard. It remains to be determined if these surface molecules are induced by the alveolar environment or if CD4(+) lymphocytes coexpressing this unusual combination of surface molecules are selectively recruited from the circulation. Our data suggest that ex vivo experiments on helper T-cell subsets that display distinctive phenotypes may be pivotal to studies on the human immune response to potential TB vaccines.

Imagery rehearsal therapy for chronic nightmares in sexual assault survivors with posttraumatic stress disorder: a randomized controlled trial

CONTEXT

Chronic nightmares occur frequently in patients with posttraumatic stress disorder (PTSD) but are not usually a primary target of treatment.

OBJECTIVE

To determine if treating chronic nightmares with imagery rehearsal therapy (IRT) reduces the frequency of disturbing dreams, improves sleep quality, and decreases PTSD symptom severity.

DESIGN, SETTING, AND PARTICIPANTS

Randomized controlled trial conducted from 1995 to 1999 among 168 women in New Mexico; 95% had moderate-to-severe PTSD, 97% had experienced rape or other sexual assault, 77% reported life-threatening sexual assault, and 58% reported repeated exposure to sexual abuse in childhood or adolescence.

INTERVENTION

Participants were randomized to receive treatment (n = 88) or to the wait-list control group (n = 80). The treatment group received IRT in 3 sessions; controls received no additional intervention, but continued any ongoing treatment.

MAIN OUTCOME MEASURES

Scores on the Nightmare Frequency Questionnaire (NFQ), Pittsburgh Sleep Quality Index (PSQI), PTSD Symptom Scale (PSS), and Clinician-Administered PTSD Scale (CAPS) at 3- and 6-month follow-up.

RESULTS

A total of 114 participants completed follow-up at 3 and/or 6 months. Comparing baseline to follow-up (n = 97-114), treatment significantly reduced nights per week with nightmares (Cohen d = 1.24; P<.001) and number of nightmares per week (Cohen d = 0.85; P<.001) on the NFQ and improved sleep (on the PSQI, Cohen d = 0.67; P<.001) and PTSD symptoms (on the PSS, Cohen d = 1.00; P<.001 and on the CAPS, Cohen d = 1.53; P<.001). Control participants showed small, nonsignificant improvements for the same measures (mean Cohen d = 0.21). In a 3-point analysis (n = 66-77), improvements occurred in the treatment group at 3-month follow-up (treatment vs control group, Cohen d = 1.15 vs 0.07 for nights per week with nightmares; 0.95 vs -0.06 for nightmares per week; 0.77 vs 0.31 on the PSQI, and 1.06 vs 0.31 on the PSS) and were sustained without further intervention or contact between 3 and 6 months. An intent-to-treat analysis (n = 168) confirmed significant differences between treatment and control groups for nightmares, sleep, and PTSD (all P<.02) with moderate effect sizes for treatment (mean Cohen d = 0.60) and small effect sizes for controls (mean Cohen d = 0.14). Posttraumatic stress symptoms decreased by at least 1 level of clinical severity in 65% of the treatment group compared with symptoms worsening or not changing in 69% of controls (chi(2)(1) = 12.80; P<.001).

CONCLUSIONS

Imagery rehearsal therapy is a brief, well-tolerated treatment that appears to decrease chronic nightmares, improve sleep quality, and decrease PTSD symptom severity.

Differential neuroprotection from human heat shock protein 70 overexpression in in vitro and in vivo models of ischemia and ischemia-like conditions

We previously showed that overexpressing the 70-kDa inducible heat shock protein in primary astrocyte cultures and in a rodent stroke model using viral vectors resulted in protection from ischemia and ischemia-like injury. However, viral transfection could potentially provoke a stress response itself; therefore, we examined whether transgenic mice constitutively expressing human heat shock protein 70 were protected from ischemic insults. Astrocyte cultures from brains of heat shock protein 70 transgenic mice were resistant to hydrogen peroxide injury in a dose-dependent fashion, but were less resistant to hypoglycemia and oxygen-glucose deprivation. Because hydrogen peroxide exposure and glucose deprivation are partially dependent on glutathione levels, we determined whether heat shock protein 70 transgenic cultures had altered glutathione levels under normal growth conditions. However, there was no significant difference in glutathione levels between heat shock protein 70 transgenic and wildtype astrocytes. Hippocampal, but not cortical neuron cultures from these same transgenic mice were also protected against oxygen-glucose deprivation and glutamate toxicity. In an in vivo model of permanent focal cerebral ischemia, there was no significant difference in infarct size assessed 24 h postinsult. These results suggest that heat shock protein 70 protects against some but not all kinds of central nervous system injury. The protective effects may be related to the nature and severity of the insults, as well as subpopulations of brain cells and dose-dependent effects of HSP70 overexpression.

The effect of conventional CR39 and Fresnel prisms on high and low contrast acuity

The effect of conventional CR39 and Fresnel prisms on high and low contrast letter acuity was studied. Visual acuity of the fully corrected better eyes of 15 subjects was measured with the high (90%) and low (10%) contrast logMAR letter charts, while they wore prisms of varying power. The results showed that when the power of the conventional CR39 prism and the Fresnel prism reached 10 prism dioptres and 5 prism dioptres, respectively, significant reduction (1 tail t-test, p < 0.05) of the high and low contrast acuity occurred. The Fresnel prism caused a significantly greater acuity reduction than the conventional CR39 prism for powers ranging from 5 to 30 prism dioptres for both contrasts. The rate of acuity reduction with increasing prism power was greater with the low contrast targets than with the high contrast targets for both prisms. In addition, the rate of acuity reduction with increasing prism power was greater with the Fresnel prism than with the conventional CR39 prism for both contrasts. The conventional CR39 prism reduced acuity by a ratio of about 0.8-0.9 of that of the Fresnel prism for powers ranging from 5 to 20 prism dioptres and by about 0.7 for 30 prism dioptres. These ratios applied for both high and low contrast acuity, and therefore were independent of the level of contrast used.

Allylic lithium oxyanionic directed and facilitated simmons-smith cyclopropanation: stereoselective synthesis of (+/-)-cis-sabinene hydrate and a novel ring expansion

[reaction: see text] The lithium salts of acid-sensitive allyl alcohols, which themselves decompose during Simmons-Smith cyclopropanation, undergo smooth cyclopropanation in the usual stereocontrolled manner. This concept is applied to the most efficient synthesis of (+/-)-cis-sabinene hydrate and to the cyclopropanation of the anion of a nonisolable allyl alcohol resulting upon workup in a ring-expanded enone. The cyclopropanations are also faster for the lithium salts than for the allyl alcohols themselves.

Role of alkali metal cation size in the energy and rate of electron transfer to solvent-separated 1:1 [(M+)(acceptor)] (M+ = Li+, Na+, K+) ion pairs

The effect of cation size on the rate and energy of electron transfer to [(M(+))(acceptor)] ion pairs is addressed by assigning key physicochemical properties (reactivity, relative energy, structure, and size) to an isoelectronic series of well-defined M(+)-acceptor pairs, M(+) = Li(+), Na(+), K(+). A 1e(-) acceptor anion, alpha-SiV(V)W(11)O(40)(5-) (1, a polyoxometalate of the Keggin structural class), was used in the 2e(-) oxidation of an organic electron donor, 3,3',5,5'-tetra-tert-butylbiphenyl-4,4'-diol (BPH(2)), to 3,3',5,5'-tetra-tert-butyldiphenoquinone (DPQ) in acetate-buffered 2:3 (v/v) H(2)O/t-BuOH at 60 degrees C (2 equiv of 1 are reduced by 1e(-) each to 1(red), alpha-SiV(IV)W(11)O(40)(6-)). Before an attempt was made to address the role of cation size, the mechanism and conditions necessary for kinetically well behaved electron transfer from BPH(2) to 1 were rigorously established by using GC-MS, (1)H, (7)Li, and (51)V NMR, and UV-vis spectroscopy. At constant [Li(+)] and [H(+)], the reaction rate is first order in [BPH(2)] and in [1] and zeroth order in [1(red)] and in [acetate] (base) and is independent of ionic strength, mu. The dependence of the reaction rate on [H(+)] is a function of the constant, K(a)1, for acid dissociation of BPH(2) to BPH(-) and H(+). Temperature dependence data provided activation parameters of DeltaH = 8.5 +/- 1.4 kcal mol(-1) and DeltaS = -39 +/- 5 cal mol(-1) K(-1). No evidence of preassociation between BPH(2) and 1 was observed by combined (1)H and (51)V NMR studies, while pH (pD)-dependent deuterium kinetic isotope data indicated that the O-H bond in BPH(2) remains intact during rate-limiting electron transfer from BPH(2) and 1. The formation of 1:1 ion pairs [(M(+))(SiVW(11)O(40)(5-))](4-) (M(+)1, M(+) = Li(+), Na(+), K(+)) was demonstrated, and the thermodynamic constants, K(M)(1), and rate constants, k(M)(1), associated with the formation and reactivity of each M(+)1 ion pair with BPH(2) were calculated by simultaneous nonlinear fitting of kinetic data (obtained by using all three cations) to an equation describing the rectangular hyperbolic functional dependence of k(obs) values on [M(+)]. Constants, K(M)(1)red, associated with the formation of 1:1 ion pairs between M(+) and 1(red) were obtained by using K(M)(1) values (from k(obs) data) to simultaneously fit reduction potential (E(1/2)) values (from cyclic voltammetry) of solutions of 1 containing varying concentrations of all three cations to a Nernstian equation describing the dependence of E(1/2) values on the ratio of thermodynamic constants K(M)(1) and K(M)(1)red. Formation constants, K(M)(1), and K(M)(1)red, and rate constants, k(M)(1), all increase with the size of M(+) in the order K(Li)(1) = 21 < K(Na)(1) = 54 < K(K)(1) = 65 M(-1), K(Li)(1)red = 130 < K(Na)(1)red = 570 < K(K)(1)red = 2000 M(-1), and k(Li)(1) = 0.065 < k(Na)(1) = 0.137 < k(K)(1) = 0.225 M(-1) s(-1). Changes in the chemical shifts of (7)Li NMR signals as functions of [Li(5)1] and [Li(6)1(red)] were used to establish that the complexes M(+)1 and M(+)1(red) exist as solvent-separated ion pairs. Finally, correlation between cation size and the rate and energy of electron transfer was established by consideration of K(M)(1), k(M)(1), and K(M)(1)red values along with the relative sizes of the three M(+)1 pairs (effective hydrodynamic radii, r(eff), obtained by single-potential step chronoamperometry). As M(+) increases in size, association constants, K(M)(1), become larger as smaller, more intimate solvent-separated ion pairs, M(+)1, possessing larger electron affinities (q/r), and associated with larger k(M)(1)() values, are formed. Moreover, as M(+)1 pairs are reduced to M(+)1(red) during electron transfer in the activated complexes, [BPH(2), M(+)1], contributions of ion pairing energy (proportional to -RT ln(K(M)(1)red/K(M)(1)) to the standard free energy change associated with electron transfer, DeltaG degrees (et), increase with cation size: -RT ln(K(M)(1)red/K(M)(1)) (in kcal mol(-1)) = -1.2 for Li(+), -1.5 for Na(+), and -2.3 for K(+).

[Cardio-pulmonary pathology of sudden death in asthma]

OBJECTIVE

To elucidate the pathological characteristics of the heart and lung in asthmatics with sudden death.

METHOD

A detail analysis of pathological data was performed on 14 patients with sudden death in asthma.

RESULTS

There was no apparent gender difference among 14 patients. 9 patients were younger than 30 years old. Pathological examination showed that bronchial infiltration of eosinophils in 14 patient (100%), thickened basement membrane of the bronchial mucosa in 12 patients (85.7%), proliferation of smooth muscle cells in 11 patients (78.6%), proliferative mucous gland in 9 patients (64.3%), mucous plug in bronchiole in 8 patients (57.1%), and cicatvization of left ventricle in 10 patients (71.4%).

CONCLUSION

Severe nonspecific airway inflammation is demonstrated in asthmatic patients with sudden death. Lesions of the left ventricle and mucous plug in bronchiole may contribute to the main cause leading sudden death.

A randomized double-blinded multicenter comparison of remifentanil versus fentanyl when combined with isoflurane/propofol for early extubation in coronary artery bypass graft surgery

We compared a fentanyl/isoflurane/propofol regimen with a remifentanil/isoflurane/propofol regimen for fast-track cardiac anesthesia in a prospective, randomized, double-blinded study on patients undergoing elective coronary artery bypass graft surgery. Anesthesia was induced with a 1-min infusion of 0.5 mg/kg propofol followed by 10-mg boluses of propofol every 30 s until loss of consciousness. After 0.2 mg/kg cisatracurium, a blinded continuous infusion of remifentanil at 1 microg. kg(-1). min(-1) or the equivalent volume rate of normal saline was then started. In addition, a blinded bolus syringe of 1 microg/kg remifentanil or 10 microg/kg fentanyl, respectively, was given over 3 min. Blinded remifentanil, 1 microg. kg(-1). min(-1) (or the equivalent volume rate of normal saline), together with 0.5% isoflurane, were used to maintain anesthesia. Significantly more patients (P < 0.01) in the fentanyl regimen experienced hypertension during skin incision and maximum sternal spread compared with patients in the remifentanil regimen. There were no differences between the groups in time until extubation, discharge from the surgical intensive care unit, ST segment and other electrocardiogram changes, catecholamine levels, or cardiac enzymes. The remifentanil-based anesthetic (consisting of a bolus followed by a continuous infusion) resulted in significantly less response to surgical stimulation and less need for anesthetic interventions compared with the fentanyl regimen (consisting of an initial bolus, and followed by subsequent boluses only to treat hemodynamic responses) with both drug regimens allowing early extubation.

IMPLICATIONS

Both fentanyl and the newer opioid remifentanil, when each is combined with isoflurane and propofol, allowed for fast-track cardiac anesthesia. The remifentanil regimen used in this study resulted in significantly less hemodynamic response to surgical stimulation.

Wiring a medical school and teaching hospital for telemedicine

The planning and installation of a telemedicine system for communication within a teaching hospital and its academic and hospital units with a capacity for accommodation of up to 400 video-stations is described. The system is intended for improving the communication between patients and health professionals, and between the health professionals themselves. It also provides the basis for improving pre-graduate teaching, especially problem-based learning, and all aspects of postgraduate teaching.

Enhanced surveillance for pregnancy-associated mortality--Maryland, 1993-1998

CONTEXT

Deaths occurring among women who are pregnant or who have had a recent pregnancy have a devastating impact on the family and community. It is important to understand the magnitude and causes of pregnancy-associated mortality so that comprehensive strategies can be formulated to prevent such deaths.

OBJECTIVE

To ascertain the number and causes of pregnancy-associated deaths using enhanced surveillance techniques.

DESIGN, SETTING, AND SUBJECTS

Retrospective, cross-sectional analysis of death certificate data of reproductive-age women, live birth and fetal death records, and medical examiner records in Maryland during 1993-1998.

MAIN OUTCOME MEASURE

Number of pregnancy-associated deaths, defined as death from any cause during pregnancy or within 1 year of delivery or pregnancy termination, by source of data and cause of death.

RESULTS

A total of 247 pregnancy-associated deaths were ascertained. Twenty-seven percent (n = 67) were identified through cause-of-death information obtained from death certificates, 70% (n = 174) through linkage of death records with birth and fetal death records, and 47% (n = 116) through review of medical examiner records. Homicide was the leading cause of pregnancy-associated death (n = 50; 20%), and cardiovascular disorders were the second-leading cause (n = 48; 19%).

CONCLUSIONS

In this Maryland sample, comprehensive identification of pregnancy-associated deaths was accomplished only after collecting information from multiple sources and including all deaths occurring up to 1 year after delivery or pregnancy termination. This enhanced pregnancy mortality surveillance led to the disturbing finding that a pregnant or recently pregnant woman is more likely to be a victim of homicide than to die of any other cause. By broadening pregnancy mortality to include all possible causes, previously neglected factors may assume increased importance in prenatal and postpartum care.

The magnesium-ene cyclization stereochemically directed by an allylic oxyanionic group and its application to a highly stereoselective synthesis of (+/-)-matatabiether. Allylmagnesium compounds by reductive magnesiation of allyl phenyl sulfides

The first example of a magnesium-ene cyclization stereochemically directed by an allylic oxyanionic group is demonstrated by a highly stereoselective synthesis of the bicyclic terpene matatabiether 10. The synthetic method is particularly valuable, not only because of the stereochemical control and the utility of the versatile hydroxyl group introduced into the product, but also because the precursor of the allylmagnesium is an allyl phenyl sulfide, which is more stable and more easily prepared in a connective fashion than the usual allyl halide precursor. Since the presence of lithium ions encourages undesirable proton transfer to the cyclized organometallic and is detrimental to the stereochemical control, the conversion of the allylic thioether to the allylmagnesium utilizes a lithium-free method involving direct reductive magnesiation in the presence of the magnesium-anthracene complex.

[The effects of intrapleural anti-TNFalpha antibody on chemical pleurodesis induced by talc slurry or doxycycline]

OBJECTIVE

To determine whether the intrapleural injection of TNFalpha neutralizing Fab antibody fragment (anti-TNFalpha Fab) would prevent the pleurodesis that occurs after the intrapleural injection of talc or doxycycline.

METHODS

In a randomized blinded placebo controlled study, 34 New Zealand white rabbits were given 400 mg/kg talc or 10 mg/kg doxycycline intrapleurally as a sclerosant via a chest tube. Half of the rabbits in each group were also given polyclonal affinity purified anti-TNFalpha Fab 2 000 units or saline as placebo immediately before and 12 hours after the injection of the sclerosants. Chest tube were aspirated at 12 hours intervals until their removal at 4 days. Rabbits were sacrificed at 28 days. The pleural fluid volume, cell counts, LDH and pleurodesis scores were compared among groups.

RESULTS

Both talc and doxycycline produced an exudative pleural effusion. The pleural fluid volume and LDH levels were significantly greater in the doxycycline group than talc group. However, the pleural fluid leukocyte counts in talc group were higher than doxycycline group. The administration of anti-TNFalpha Fab had no significant effect on pleural fluid volume, LDH or leukocyte counts in either groups. However, the intrapleural administration of anti-TNFalpha Fab results in a significant decrease in the pleurodesis score for the talc group than doxycycline group (1.8 +/- 0.9 vs 3.2 +/- 0.8). In contrast the pleurodesis score was virtually identical in the doxycycline group with (3.5 +/- 0.5) and without (3.4 +/- 0.7) anti-TNFalpha Fab.

CONCLUSION

The intrapleural administration of anti-TNFalpha Fab diminishes the pleurodesis induced by talc but not that which results from doxycycline. These findings suggest that different mechanisms are involed with the two different sclerosants.

Vascular endothelial growth factor level correlates with transforming growth factor-beta isoform levels in pleural effusions

BACKGROUND

Recent studies have demonstrated high levels of vascular endothelial growth factor (VEGF) in exudative pleural effusions and a possible etiologic role. The factors regulating VEGF accumulation in the pleural space are unknown. Transforming growth factor (TGF)-beta is a potent stimulator of VEGF expression in vitro. We hypothesized that TGF-beta induces VEGF production in pleural tissues, and, hence, the pleural fluid VEGF levels should correlate with the levels of TGF-beta in pleural fluid of different etiologies.

METHODS

Seventy pleural fluid samples were analyzed. These included 20 malignant, 13 post-coronary artery bypass grafting (CABG), 8 parapneumonic, 11 miscellaneous exudative, and 18 congestive heart failure (CHF) pleural effusions.

RESULTS

Pleural fluid VEGF levels showed good correlation with those of TGF-beta(1) (r = 0.58; p < 0. 0001), TGF-beta(2) (r = 0.43; p < 0.001), and lactate dehydrogenase (r = 0.65; p < 0.001). The levels of TGF-beta(1) and TGF-beta(2) also were correlated (r = 0.60; p < 0.0001). The median levels of TGF-beta(1) (2,480 pg/mL) and TGF-beta(2) (266 pg/mL) in the CHF group were significantly lower than those in the malignant (TGF-beta(1), 4,902 pg/mL; TGF-beta(2), 428 pg/mL), post-CABG (TGF-beta(1), 5,456 pg/mL; TGF-beta(2), 377 pg/mL), parapneumonic (TGF-beta(1), 5,024 pg/mL; TGF-beta(2), 464 pg/mL), and miscellaneous exudate groups (TGF-beta(1), 7,690 pg/mL; TGF-beta(2), 369 pg/mL). There was no significant difference in TGF-beta(1) and TGF-beta(2) levels among the four exudate groups.

CONCLUSIONS

VEGF levels in pleural effusions are significantly correlated with the levels of TGF-beta(1) and beta(2) isoforms. VEGF, TGF-beta(1), and TGF-beta(2) levels were all higher in exudative effusions than in effusions secondary to CHF.

P73 gene expression in ovarian cancer tissues and cell lines

Thep73 gene, a homology of p53, is a new candidate of imprinting and tumor suppressor gene. To investigate the role of p73 in ovarian cancer, we studied the allelic expression in 56 cases of ovarian cancer using StyI polymorphism analysis. We also examined p73 expression by semi-quantitative reverse transcription-PCR as well as by Western blot analysis and DNA methylation study of the CpG island in exon 1 in ovarian cancer tissues and cell lines. Loss of heterozygosity was found in 8.3% (2 of 24) of the cases. Biallelic expression was demonstrated in 91.7% (22 of 24) of the tumor samples, in 70.8% (17 of 24) of the normal samples, and in 1 ovarian cancer cell line. Imbalanced expression and monoallelic expression were found in three and two pairs of matched samples, respectively. Overexpression of p73 was found in advanced ovarian cancer rather than in early-stage disease or in borderline ovarian tumor. No significant difference was found in the p53 expression. Three cell lines with absent p73 protein expression and one tumor sample with monoallelic expression were methylated in the CpG island. Demethylation in SKOV3 cell line using 5-azacytidine can reactivate the expression of this gene in both the mRNA and the protein level. Our results indicated that p73 was not imprinted in most of the ovarian cancer and normal tissues, but it could be involved in the advanced ovarian cancer through overexpression. DNA methylation may contribute to the lack of p73 expression.

A controlled study of imagery rehearsal for chronic nightmares in sexual assault survivors with PTSD: a preliminary report

Imagery-rehearsal therapy for chronic nightmares was assessed in a randomized, controlled study of sexual assault survivors with posttraumatic stress disorder (PTSD). Nightmares, sleep quality, and PTSD were assessed at baseline for 169 women, who were randomized into two groups: treatment (n = 87) and wait-list control (n = 82). Treatment consisted of two 3-hr sessions and one 1-hr session conducted over 5 weeks. Of 169 participants, 91 women (Treatment, n = 43, Control, n = 48) completed a 3-month follow-up and 78 did not. At follow-up, nightmare frequency and PTSD severity decreased and sleep quality improved in the treatment group with small to minimal changes in the control group. Treatment effects were moderate to high (Cohen's d ranged from 0.57 to 1.26). Notwithstanding the large dropout rate, imagery-rehearsal therapy is an effective treatment for chronic nightmares in sexual assault survivors with PTSD and is associated with improvement in sleep quality and decreases in PTSD severity.

[Effects of endothelin receptor antagonist on the hypoxic pulmonary hypertension]

This investigation was made to elucidate the role of endothelin (ET) in hypoxic pulmonary hypertension and the preventing effects of BQ-123, an ETA receptor antagonist. Thirty male Wistar rats were divided into three groups and exposed to air, isobaric hypoxia or isobaric hypoxia plus BQ-123 for 3 weeks. The pulmonary artery pressure was measured by right cardiac catheterization. The plasma level of ET-1 was measured by RIA method. Histologic sections of the lungs were examined by a computerized image analyser. In hypoxic rats, the pulmonary artery pressure and the thickness of wall of arteriole were significantly increased, and right ventricular hypertrophy was developed. The plasma level of VEGF in rats treated with hypoxia (192.3 +/- 43.1 pg/ml) was significantly increased as compared with that of normal rats (128.2 +/- 28.1 pg/ml), P < 0.01. Chronic BQ-123 treatment prevented the developments of pulmonary hypertension, thickening of pulmonary arteriole and right ventricular hypertrophy induced by hypoxia. These result indicate that chronic hypoxia can result in hypoxic pulmonary hypertension and increased plasma level of ET-1, and the ETA receptor antagonist can prevent hypoxic pulmonary hypertension.