Long-term efficacy of plasma-derived hepatitis B vaccine: a 15-year follow-up study among Chinese children

To determine necessity and timing of booster of hepatitis B vaccine, we need to observe the duration of its protection. We report the results of a 15-year follow-up of a cohort of 649 children who participated a randomized, double blind, placebo-controlled trial on a plasma-derived hepatitis B vaccine in 1982. During the 15 years after vaccination, more vaccinated children had anti-HBs of 10 S/N ratios or over, compared with the controls, at all nine observations. At 15 years 50.0% (26/52) of the participants studied in the vaccinated group and 33.3% of the tested controls (18/54) retained anti-HBs levels of S/N ratios> or =10 (P < 0.09). However, since 5 years after vaccination, median S/N ratios of anti-HBs among the vaccinated children with detectable anti-HBs were lower than those of the controls except that detected at 15 years. 16.7% (9/54) of the tested children in the control group were HBsAg positive at 15 years after vaccination, in comparison with 1.9% (1/52) of the tested children in the vaccinated (P < 0.02). 28 chronic HBsAg carriers were identified in the control cohort over the 15 years, whereas only 1 case was noted in the vaccinated group (8.2% vs. 0.3%, P < 0.00001), corresponding to an efficacy of 96%.

Dynamics of nontypical apoptotic morphological changes visualized by green fluorescent protein in living cells with infectious pancreatic necrosis virus infection

Morphologically, apoptotic cells are characterized by highly condensed membrane blebbing and formation of apoptotic bodies. Recently, we reported that apoptosis precedes necrosis in a fish cell line infected with infectious pancreatic necrosis virus (IPNV). In the present study, we tested the possibility that nontypical apoptosis is a component of IPNV-induced fish cell death. A variant type of green fluorescent protein (EGFP) was expressed in a fish cell line such that EGFP served as a protein marker for visualizing dynamic apoptotic cell morphological changes and for tracing membrane integrity changes during IPNV infection. Direct morphological changes were visualized by fluorescence microscopy by EGFP in living cells infected with IPNV. The nontypical apoptotic morphological change stage occurred during the pre-late stage (6 to 7 h postinfection). Nontypical apoptotic features, including highly condensed membrane blebbing, occurred during the middle apoptotic stage. At the pre-late apoptotic stage, membrane vesicles quickly formed, blebbed, and were finally pinched off from the cell membrane. At the same time, at this pre-late apoptotic stage, apoptotic cells formed unique small holes in their membranes that ranged from 0.39 to 0.78 micrometer according to examination by scanning electron microscopy and immunoelectron microscopy. Quantitation of the intra- and extracellular release of EGFP by CHSE-214-EGFP cells after IPNV infection was done by Western blotting and fluorometry. Membrane integrity was quickly lost during the late apoptotic stage (after 8 h postinfection), and morphological change and membrane integrity loss could be prevented and blocked by treatment with apoptosis inhibitors such as cycloheximide, genistein, and EDTA before IPNV infection. Together, these findings show the apoptotic features at the onset of pathology in host cells (early and middle apoptotic stages), followed secondarily by nontypical apoptosis (pre-late apoptotic stage) and then by postapoptotic necrosis (late apoptotic stage), of a fish cell line. Our results demonstrate that nontypical apoptosis is a component of IPNV-induced fish cell death.

Levels of paraquat in fatal intoxications

We describe here fatal levels of paraquat in plasma of victims due to the ingestion of the herbicide, paraquat, and the relationship between those levels and survival times after ingestion. We determined paraquat levels in plasma of 106 paraquat poisoning cases in Korea between June 1992 and December 1996 using a visible spectrophotometric method based on the alkali-dithionite reaction. Among 55 cases with known survival times, plasma paraquat levels of victims who died within one day of ingestion ranged from 2.3 to 636.6 microg/ml (average 127.6 microg/ml) while those of the victims who died between 1 approximately 4 days ranged from 0.9 to 25.1 microg/ml (average 7.0 microg/ml). Since preparations containing 24.5% paraquat dichloride are still used in Korea, our data for Korean victims who died within one day were 8.5 times higher than those in Baselt and Cravey's report for the same survival times. Our data also suggest that victims in whom a plasma paraquat concentration of more than 30 microg/ml was detected are likely to have died within 24 h after ingestion.

Assessment of myocardial viability using 123I-labeled iodophenylpentadecanoic acid at sustained low flow or after acute infarction and reperfusion

123I-labeled iodophenylpentadecanoic acid (IPPA) is a synthetic fatty acid that may be useful for determination of myocardial viability. We investigated the uptake and clearance kinetics of this tracer in canine models of ischemia and infarction.

METHODS

In protocol 1, 185 MBq (5 mCi) 123I-IPPA were injected intravenously in 19 dogs with 50% left anterior descending artery (LAD) flow reduction. In 9 dogs, 201TI was coinjected. In protocol 2, 5 dogs underwent LAD occlusion for 3 h, and 123I-IPPA was injected 60 min after reperfusion. All dogs had flow measured by microspheres, regional systolic thickening by ultrasonic crystals and measurements of postmortem risk area and infarct size. Tracer activities were quantified by gamma well counting and by serial imaging.

RESULTS

In protocol 1 dogs with sustained low flow (50% +/- 4%) and absence of systolic thickening (-3.2% +/- 1%), 123I-IPPA defect magnitude (LAD/left circumflex artery [LCX] count ratios) decreased from 0.65 +/- 0.02 to 0.74 +/- 0.02 at 30 min and to 0.84 +/- 0.03 at 2 h (P < 0.01), indicative of rest redistribution. Final transmural 123I-IPPA LAD/LCX activity ratio (0.99 +/- 0.05) was significantly greater than the flow ratio (0.53 +/- 0.04) at injection, confirming complete rest redistribution. The final 123I-IPPA activity ratio was significantly greater than the 201TI ratio over the 2-h period (P < 0.01). In protocol 2 dogs that underwent 3 h of total LAD occlusion and reflow (infarct size = 51% +/- 13% of risk area), viability was overestimated with 123I-IPPA, because uptake averaged 64% of normal in the central necrotic region, where flow averaged < 10% of normal.

CONCLUSION

These findings suggest that serial 123I-IPPA imaging may be useful for assessing myocardial viability under conditions of sustained low flow and myocardial asynergy, such as appears to exist in patients with chronic coronary artery disease and depressed left ventricular function. In contrast, 123I-IPPA given early after reperfusion following prolonged coronary occlusion overestimates the degree of viability and therefore may not provide useful information pertaining to the degree of myocardial salvage after reflow in the setting of acute myocardial infarction.

Symptomatic tracheal stenosis in burns

Tracheal stenosis in burns is rare and usually results from prolonged intubation or tracheostomy. Inhalation injury itself has the potential risk of tracheal stenosis. We reviewed the records of 1878 burn patients during 1987 to 1995 and found seven with tracheal stenosis (0.37%) after an average of 4.4 years follow up. There were 4 males and 3 females with an average age of 27.3 years. The tracheal stenosis developed 1-22 months after burn (average 7 months). Five patients had their inhalation injury confirmed by bronchoscopic examination. The incidence of tracheal stenosis among inhalation injury patients was 5.49% (5/92). Six patients needed intubation in the initial stage either for respiratory distress or prophylaxis, with an average duration of 195.2 h. In addition to prolonged intubation, the presence of inhalation injury, repeated intubations and severe neck scar contractures are also contributors to tracheal stenosis in burns. We favor T-tube insertion as the first treatment choice; permanent tracheostomy was unsatisfactory in our study.

Heterozygous defect in HIV-1 coreceptor CCR5 and chemokine production

CC chemokine receptor 5 (CCR5) is a cell entry cofactor for macrophage-tropic isolates of human immunodeficiency virus 1 (HIV-1). An inactive CCR5 allele with a 32-nucleotide deletion (CCR5Delta32) has been described that confers resistance to HIV-1 infection in homozygotes and slows the rate of progression to AIDS in heterozygotes. We found the allele CCR5Delta32 to be not rare in 399 Swiss blood donors with a frequency of 0.080. To assess the influence of defective CCR5 on production of its ligands we determined the capacity to produce the chemokines macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and RANTES in comparison with the production of the CXC chemokine IL-8 which does not bind to CCR5. Production of chemokines was determined during endotoxin stimulation of whole-blood samples ex vivo. Both, basal and LPS-induced chemokine production in 32 blood donors heterozygous for CCR5Delta32 were not significantly different when compared with 55 blood donors who were homozygous for the wild type CCR5 allele.

Pilot in vitro toxicity study of 5-ALA and Photofrin in microvascular endothelial cell cultures

Complicated hemangiomas are unique problems in which intervention with the proper laser can be an ideal solution. In this study we evaluated the toxicity of 5-Aminolevulinic acid (5-ALA) and Photofrin using in vitro models. The in vitro toxicity of 5-ALA and Photofrin was examined in a microvascular endothelial cell (MEC) culture system. The measurement of the percentage of MEC killed by various drug concentration using fluorescence viability assay. MEC incubated with 5-ALA at various concentrations for evaluation of dark toxicity showed less than a 50% cell kill. A comparison of different intervals of subcultured MEC showed that the early subculture (3 days after primary culture) is more vulnerable than later subculture (7 days after). Cells treated with Photofrin at various concentrations exhibited less than 50% cell kill (dark toxicity). The comparison of different intervals of subculture (3 days and 7 days after primary culture) showed a result similar to that of 5-ALA. All controls showed 0% cell kill. In conclusion, both 5-ALA and Photofrin are capable of destroying human microvascular endothelial cells in vitro. Drug concentrations and the power density for photodynamic therapy should be considered and will be included in our subsequent studies.

Effect of antioxidant in endothelial cells exposed to oxidized low-density lipoproteins

Antioxidants such as probucol and alpha-tocopherol have been shown to attenuate the oxidation of low-density lipoproteins (LDL) and atherosclerotic lesions in animal models of atherosclerosis. The purpose of this study is to determine the protection effect of antioxidants on endothelial cells when exposed to oxidized and native LDL. In a cell-free system, we found that probucol, alpha-tocopherol, and ascorbic acid inhibited copper-induced LDL oxidation by a dose-dependent fashion (from 1 microM to 10 mM). In porcine aortic endothelial cells, antioxidants alone did not change basal endothelin-1 (ET-1) secretion. When porcine aortic endothelial cells were exposed to LDL and oxidized-LDL, both of them stimulated ET-1 secretion dose-dependently, whereas oxidized-LDL elicited higher ET-1 secretion. However, probucol, alpha-tocopherol, and ascorbic acid did not prevent LDL or oxidized-LDL induced ET-1 secretion. Furthermore, nimodipine inhibited both of native and oxidized LDL induced ET-1 secretion. Since Ca2+ channel blocker reduced the elevation of induced ET-1 secretion, the [Ca2+]i is possibly involved for the regulation of ET-1 secretion. Our results suggest that antioxidants can only prevent the oxidation of LDL rather than oxidized and native LDL-induced ET-1 secretion in vascular endothelial cells. The increase in the [Ca2+]i of endothelial cells through the opening of voltage-dependent Ca2+ channels may be involved in the LDL-induced ET-1 release.

Clinical experience of postage stamp autograft with porcine skin onlay dressing in extensive burns

Fifteen patients with extensive burns (deep second-degree burn > 50%, or third-degree burn > 30% of total body surface area) were treated with postage stamp autograft and meshed porcine skin onlay dressing from 1992 to 1996. All patients received the procedure within 10 days of sustaining the burn, with an average of 6.3 days. The areas chosen for postage stamp autograft were the anterior chest, abdomen, back, buttocks and the proximal part of the extremities. The scalp was the donor site of choice when available. The harvested skin was cut into 0.5-1.0 cm postage-stamp-like squares and applied to the recipient sites separated by a distance of 0.5-2.0 cm. The expansion ratio was from 1:4 to 1:9. Meshed porcine skin was then used for onlay dressing. The average graft area was 26% of the total body surface area. The success rate of the skin grafts was nearly 100% in 14 patients. One patient had a 40% loss due to contamination from adjacent wounds. In conclusion, the postage stamp autograft with porcine skin overlay is an effective way to treat extensive burn wounds in the early stages.

The interaction of glomerular mesangial cells and epithelial cells

The interaction of cells within the glomerulus plays an important role in the development and progression of glomerular disease. To investigate the interaction of glomerular mesangial cells (GMC) and epithelial cells (GEC), and mediator(s) of this interaction, we investigated the effect of Adriamycin (doxorubicin hydrochloride)-induced (ADR) rat GMC-conditioned medium (GMC-CM) on the incorporation of 35S, 3H-leucine, and 3H-thymidine in normal rat GEC, as well as 3H-thymidine uptake by normal rat GMC in response to ADR-rat GEC-CM. In addition, changes in the responsiveness to interleukin-6 (IL-6) and the products of IL-6 were assessed in ADR-rat GMC. The results showed that: (1) GMC-CM of ADR-rat with heavy proteinuria stimulated GEC proliferation and the synthesis of sulfated compounds and protein, while the GEC-CM of ADR-rat from the same nephrotic period increased GMC proliferation; (2) the ADR-rat GMC had altered responsiveness to IL-6 and its products. The stimulation index results demonstrated the interaction of GMC and GEC in the ADR-induced rat model, and that this interaction related closely to the degree of proteinuria and was mediated by soluble products of the damaged glomerular cell.

Use of the scalp as a donor site for large burn wound coverage: review of 150 patients

The characteristics of rapid wound healing and multiple harvest capacity make the scalp an important donor site when dealing with large and deep burn wounds. This paper reports the results of a retrospective analysis of 150 patients treated for large burn wounds. The findings indicated that bleeding during graft skin harvest could be limited to 50 ml by intradermal injection of epinephrine (1:2,000,000), high-concentration epinephrine-soaked gauze compression (1:20,000), and temporary porcine skin coverage. Use of a scalp graft also carried a low risk of complications, with only four (2.7%) major complications including three cases (2.0%) of visible alopecia and one case (0.7%) of hair transplantation. There were no hypertrophic scars, even in the patient who had the largest number (11) of repeat harvests.

Mutational analysis of domain II beta of bacteriophage Mu transposase: domains II alpha and II beta belong to different catalytic complementation groups

This study examines the contribution of domain II beta of bacteriophage Mu transposase (A protein), a subdomain of the central catalytic domain II, to the transposition reaction. The properties of several point mutations implicate a role for this domain in facilitating metal-assisted assembly of the synaptic complex, as well as in intramolecular DNA strand transfer. Point mutations as well as deletions in domain II beta can be complemented by those in domain II alpha but not those in domain III alpha. Thus, residues within subdomains II alpha and II beta belong to different catalytic complementation groups.

Surveillance of anti-hantavirus antibodies among certain high-risk groups in Taiwan

Hemorrhagic fever with renal syndrome is a serious health concern in neighboring countries of Taiwan, such as mainland China and Korea. In Taiwan, only two suspected cases were recorded before 1994. The first confirmed case was reported in 1995, but this proved to be imported. To study hantavirus infection in Taiwan, we tested blood collected from garbage collectors, animal handlers, patients with febrile illness of unknown origin, and field rats, the host of hantavirus, for the presence of antibody against hantavirus using an indirect immunofluorescent antibody technique. The positive rates were 1.55% (3/193), 3.45% (1/29), 1.42% (3/211), and 5.56% (9/162), respectively. The subtypes of hantavirus involved were either Hantaan-like or Seoul-like. These results showed that hantavirus may have already invaded Taiwan without our knowledge and physicians should be aware of this.

A randomized, double-blind clinical trial comparing cefepime plus metronidazole with imipenem-cilastatin in the treatment of complicated intra-abdominal infections. Cefepime Intra-abdominal Infection Study Group

OBJECTIVE

To evaluate the safety and efficacy of cefepime hydrochloride plus metronidazole vs the combination of imipenem and cilastatin sodium in the treatment of complicated intra-abdominal infections in adult patients.

DESIGN

Prospective, randomized, double-blind multicenter study.

SETTING

University-affiliated hospitals in the United States and Canada.

PATIENTS

Three hundred twenty-three patients with complicated intra-abdominal infections in whom an operative procedure or percutaneous drainage was required for diagnosis and management.

INTERVENTION

Cefepime, 2 g, was administered intravenously every 12 hours (n= 164) in addition to metronidazole, 500 mg (or 7.5 mg/kg) intravenously every 6 hours. Imipenen-cilastatin sodium, 500 mg, was administered intravenously every 6 hours (n= 159). Surgical infection management was determined by the patients' surgeons. MAIN OUTCOME ASSESSMENTS: Clinical cure, defined as elimination of all signs and symptoms relevant to the original infection; and treatment failure, defined as persistence, increase or worsening of signs and symptoms resulting in an antibiotic change, requirement of an additional surgical procedure to cure the infection, or a wound infection with fever.

RESULTS

Of the initial isolates, 84% were susceptible to cefepime and 92% were susceptible to imipenem-cilastatin. Among the 217 protocol-valid patients, those treated with cefepime+metronidizole were deemed clinical cures (88%) more frequently than were imipenem-cilastatin-treated patients (76%) (P=.02). Using multivariate analysis to adjust for identified clinical risk factors for an adverse outcome (severity of presenting illness, isolation of enterococcus, type of infection, and duration of prestudy hospitalization), there was a trend (P=.06) toward a higher cure rate favoring cefepime+metronidazole. Pathogens were eradicated in significantly (P=.01) more patients treated with combined cefepime and metronidazole (89%) than with imipenem-cilastatin (76%).

CONCLUSION

The combination of cefepime plus metronidazole is safe and effective therapy for patients with severe intra-abdominal infections.

Antioxidants for prevention of methionine oxidation in recombinant monoclonal antibody HER2

Recombinant humanized monoclonal antibody HER2, rhuMAb HER2, in liquid formulations undergoes oxidation when exposed to intense light and elevated temperatures (30 & 40 degrees C). Met-255 in the heavy chain of the Fc region of the antibody is the primary site of oxidation. Met-431 of the Fc fragment can also be oxidized under extreme conditions. The amount of oxidation was determined by cleaving the Fab and Fc fragments by papain digestion, and the oxidized Fc fragment was detected by hydrophobic interaction chromatography. Oxidation of rhuMAb HER2 was also formulation dependent. The presence of NaCl in the rhuMAb HER2 formulation caused an increase in oxidation at higher temperatures after contact with stainless steel containers or stainless steel components in the filling process. The corrosion of stainless steel by chloride ions at the low pH of the formulation buffer generated iron ions that catalyzed methionine oxidation in rhuMAb HER2. Temperature-induced oxidation of rhuMAb HER2 occurred by the formation of free radicals, and light-induced oxidation of rhuMAb HER2 occurred via single oxygen pathway. Antioxidants, such as methionine, sodium thiosulfate, catalase, or platinum, prevented Met oxidation in rhuMAb HER2, presumably as free radicals or oxygen scavengers. The minimum effective levels (molar ratios of protein to antioxidant) required to inhibit temperature-induced oxidation were 1:5 and 1:25 for methionine and thiosulfate, respectively. A thiosulfate adduct of rhuMAb HER2 was observed by cation-exchange chromatography. These studies demonstrate that stoichiometric amounts of methionine and thiosulfate are sufficient to eliminate temperature-induced oxidation of rhuMAb HER2 caused by free radicals that were generated by the presence of metal ion and peroxide impurities in the formulation.

Myocardial 99mTc-tetrofosmin uptake during adenosine-induced vasodilatation with either a critical or mild coronary stenosis: comparison with 201Tl and regional myocardial blood flow

BACKGROUND

Clinical studies have shown a comparable coronary stenosis detection rate between 99mTc-tetrofosmin and 201Tl but with smaller defect magnitudes for 99mTc-tetrofosmin. The goals of this study were to measure the first-pass extraction fraction (EF) of 99mTc-tetrofosmin in canine myocardium and to compare 99mTc-tetrofosmin with 201Tl uptake during adenosine-induced vasodilatation in dogs with various degrees of coronary stenosis.

METHODS AND RESULTS

EF was calculated in 4 anesthetized, open-chest dogs after intracoronary administration of 125I-labeled albumin and 99mTc-tetrofosmin. In another 16 dogs with either critical (n=6) or mild (n= 10) left anterior descending coronary artery (LAD) stenoses, 201Tl and 99mTc-tetrofosmin were administered during adenosine infusion (250 microg x kg(-1) x min(-1)). Dogs were killed 5 minutes later, and tracer activities were determined by ex vivo imaging of heart slices and by well counting. Mean 99mTc-tetrofosmin EF was 54.0+/-3.7%. In the 6 critical-stenosis dogs, the LAD-to-left circumflex artery (LCx) microsphere flow ratio was 0.22+/-0.02 with adenosine. The LAD-to-LCx activity ratios were 0.37+/-0.04 for 201Tl and 0.67+/-0.05 for 99mTc-tetrofosmin (P<.01). For the 10 mild-stenosis dogs, the LAD-to-LCx flow ratio was 0.44+/-0.05. The 201Tl activity ratio was 0.58+/-0.04, compared with 0.81+/-0.04 for 99mTc-tetrofosmin (P<.01). Thus, in both groups, 99mTc-tetrofosmin uptake underestimated the flow disparity more than 201Tl. Similarly, magnitudes of ex vivo image defects were significantly greater for 201Tl than for 99mTc-tetrofosmin in both groups.

CONCLUSIONS

In this canine model, relative underperfusion with adenosine stress is better resolved with 201Tl than with 99mTc-tetrofosmin and may be explained by the lower EF for 99mTc tetrofosmin. With clinical imaging, greater 201Tl attenuation and redistribution may lessen this advantage.

Alport syndrome with neurofibromatosis type-I: a case report

We report a 9-year-old boy with repeated fractures of the tibia from age 6 months and microscopic hematuria from age 2 years. His maternal family has a history of nephritis and his paternal family has neurofibromatosis type-I (NF-I). The boy's renal biopsy revealed an irregular attenuation and splitting of the glomerular basement membrane. The skin biopsy was stained with monoclonal antibody against the alpha 5 chain of type IV collagen; the epidermal basement membrane was negative in the boy and segmentally positive in the boy's mother. We conclude that the patient inherited Alport syndrome from his mother and NF-I from his father. We postulate this was a chance association and that this case does not suggest any relationship between the two diseases.

99Tcm-MDP scintigraphy in high-voltage electrical burn patients

In high-voltage electrical burn injuries (> 1000 V), it is difficult to identify the site and extent of non-viable deep tissue damage for debridement to avoid further tissue injury from wound infection and the risk of sepsis. This prospective study was designed to evaluate the usefulness of 99Tcm-methylene di-phosphonate (99Tcm-MDP) scintigraphy in detecting the extent of tissue injury and determining the level of amputation required for electrical burn patients. Over a 5 year period, 33 high-voltage electrical burn patients were studied. Blood flow and blood pool studies revealed absent perfusion in 37 limbs, all of which eventually were amputated. In addition to a routine three-phase bone scan, images were obtained at 30-60 min (early images) to evaluate whether soft tissue injury could be detected better at that time. For comparison of the detection rate from the early images and bone (delayed) images, 164 corresponding spot views of both images were reviewed. Eighty-three and 125 tissue necrotic lesions were demonstrated by the early images and bone images respectively. All of the 83 lesions found by the early images were more clearly identified by the bone images. All but one of the 125 lesions underwent surgical debridement or amputation. We concluded that the blood flow and blood pool images correlated well with the level of amputation required. The site and extent of tissue necrotic lesions can be clearly identified on 99Tcm-MDP bone scans. Because the early images were less sensitive in detecting tissue necrosis, we suggest that early imaging is not necessary.

Structure and origin of HIV type 1 DNA in persistently infected B lymphoblastoid cell lines

The Epstein-Barr virus (EBV) and human immunodeficiency virus type 1 (HIV-1) can coinfect resting B cells, leading to EBV-carrying lymphoblastoid cell lines (LCLs) persistently infected with HIV-1. LCLs established from coinfected peripheral blood lymphocytes (PBLs) differed from LCLs derived from HIV-1-infected cell lines, in that the majority if not all of the cells expressed gp120 and a high percentage produced infectious HIV-1 after continuous passage for 6-9 months. Restriction analysis of the putative HIV-1 provirus revealed that persistently infected LCLs carried variable copies of primarily unintegrated circular and/or linear forms of HIV-1 DNA. This extrachromosomal location is strikingly different from that of the one to three copies of integrated proviral DNA deleted in persistently infected T cell and monocytic cell lines. Anti-gp120 monoclonal antibody and 3'-azido-3'-deoxythymidine (AZT) inhibited HIV-1 expression and reduced HIV-1 DNA copy number in persistently infected LCLs, supporting the hypothesis that unintegrated HIV-1 DNA accumulates primarily as a result of superinfection. We propose that the extrachromosomal location of the HIV-1 DNA contributes to the semipermissive nature of B cell infection by HIV-1.

Temperature effect on the sensitivity of ELISA, PA and WB to detect anti-HIV-1 antibody and infectivity of HIV-1

BACKGROUND

This study is designed to resolve the problem of whether temperature or freeze/thaw cycle will have any impact on the sensitivity for detection of anti-HIV-1 antibody by particle agglutination (PA), enzyme-linked immunosorbent assay (ELISA) and western blotting (WB). To reduce potential risk for laboratory personnel exposed to HIV-infection, it will be useful to determine the temperature effect on HIV infectivity.

METHODS

Testing sera were incubated at different temperatures or treated with several cycles of freeze and thaw. PA, ELISA and WB were used to detect anti-HIV-antibodies, whereas syncytia formation assay and polymerase chain reaction (PCR) were applied to detect HIV-infection.

RESULTS

The data showed that certain temperature points (no treatment, 25 degrees C for 1 hr, 2 hrs and 4 hrs, 37 degrees C for 30 minutes and 60 minutes, 56 degrees C for 30 minutes and 60 minutes, 65 degrees C for 15 minutes and 30 minutes) had no impact on the testing results of ELISA, PA and WB in detection of anti-HIV-1 antibody. In addition, testing results of 50 normal human serum samples which had been heated to 56 degrees C for 30 minutes were still negative by ELISA and PA. Only the samples incubated at 65 degrees C for 60 minutes had slight differences in results. Freeze and thaw treatments of the serum did not alter anti-HIV testing results, either. Treatments of supernatant of HTLV-IIIB culture at 56 degrees C for 30 minutes and 60 minutes, 65 degrees C for 15 minutes and 30 minutes could eliminate the syncytia formation caused by HIV-infection. Further analysis of the samples by PCR was able to detect HIV-specific sequences in all the treatments.

CONCLUSIONS

Anti-HIV antibody is quite stable in serum, even when it is pre-heated to 56 degrees C for 30 minutes. Freeze and thaw treatment of serum samples up to seven cycles did not change the results, either. In addition, to minimize the potential risk of laboratory personnel exposed to HIV infection, pre-treatment of serum samples with heat at 56 degrees C for 30 minutes or 60 minutes can reduce HIV infectivity. However, laboratories still must emphasize the importance of universal precautions rather than heat-inactivation of serum to prevent occupational transmission of HIV.

Effect of carbonyl cyanide m-chlorophenylhydrazone (CCCP) on the dimerization of lipoprotein lipase

Lipoprotein lipase (LPL), an enzyme playing the central role in triglyceride metabolism, is a glycoprotein and a homodimer of identical subunits. Dimerization and proper processing of oligosaccharide chains are important maturation steps in post-translational regulation of enzyme activity. Indirect evidences suggest that dimerization of LPL occurs in endoplasmic reticulum (ER) or Golgi. In this study, we investigated the dimerization status of LPL in 3T3-L1 adipocytes, using sucrose density gradient ultracentrifugation and carbonyl cyanide m-chlorophenylhydrazone (CCCP), an inhibitor of ER-Golgi protein transport. In the presence of CCCP, no increase of cellular LPL activity was detected during 2 b of recovery period after the depletion of LPL, with heparin and cycloheximide. Only endoglycosidase H (endo H)-sensitive subunits were found in CCCP-treated cells after endo H digestion, suggesting that inactive LPL was retained in ER. In the presence of castanospermine, an inhibitor of ER glucosidase I, LPL subunits of both control and CCCP-treated cells had same molecular weight, indicating that complete oligosaccharides were transferred to LPL subunits in the presence of CCCP. In sucrose density gradient ultracentrifugation, all the LPL protein synthesized in the presence of CCCP was found at the dimeric fractions as in control cells. Most of LPL protein in control cells showed high affinity for heparin, and there was no difference between the control and CCCP-treated cells. These results suggest that dimerization and acquisition of high affinity for heparin of LPL can occur in ER of CCCP-treated cells without acquisition of catalytic activity.

Synergy between human immunodeficiency virus type 1 and Epstein-Barr virus in T lymphoblastoid cell lines

CR2 (CD21), the EBV receptor, was detected on three of four CD4-positive cell lines by indirect fluorescent labeling, and its corresponding mRNA was found by use of the reverse transcription-based polymerase chain reaction. To determine whether CR2 on CD4-positive cells was functional, their ability to be infected by EBV was analyzed. EBV DNA, EBV nuclear antigen 2 (EBNA-2A), and EBV-encoded small RNA (EBER1) transcripts could be detected in CR2-expressing CD4-positive cells following infection by the B95.8 strain of EBV. Analysis of the terminal region showed the EBV genome remained linear following infection, and copy number decreased with time. Since CD4-positive cell lines are targets for HIV-1 infection, the effects of EBV infection on HIV-1 expression were analyzed. HIV-1 replication was upregulated when CD4-positive cells were coinfected with EBV strain B95.8 but not P3HR-1K. These results suggested that EBNA-2 is involved in upregulation of HIV-1 expression in T lymphoblastoid cell lines. To test this hypothesis an EBNA-2-expression vector was transfected into T lymphoblastoid cell lines and HIV-1 expression measured. First, trans-activation of HIV-1 long terminal repeat (LTR) by Tat was enhanced by EBNA-2 type 1 expression. trans-Activation of the HIV-1 LTR by Tat was also enhanced when CD4-positive cells were infected by EBV (strain B95.8) encoding an intact EBNA-2, but not by P3HR-1K with a deleted EBNA-2. In addition, CD4-positive cell clones stably expressing EBNA-2 supported enhanced HIV-1 replication as measured by accumulation of reverse transcriptase activity and syncytium induction. This provides direct evidence that EBV infection can enhance HIV-1 replication in T cells. Whether this in vitro phenomenon contributes to disease progression in vivo remains to be determined.

Labor pain before elective cesarean section reduces neonatal respiratory distress

Neonatal respiratory distress is a major complication of elective Cesarean section. To clarify the effect of preceding labor on the incidence of respiratory distress, we studied 45 term neonates who were born with labor and 85 term neonates who were born without labor. Transient tachypnea of the newborns accounted for the majority of respiratory distress in term neonates. Respiratory distress occurred less frequently in term neonates delivered after the onset of labor compared to those delivered before the onset of labor (11.1% vs. 31.8%, p < 0.002). Neonatal respiratory distress syndrome (RDS) occurred in 4 of 85 (4.7%) term neonates delivered before the onset of labor. In contrast, none of the 45 term neonates born after the onset of labor developed RDS (p = 0.02). Awaiting the onset of labor appears to be beneficial in preventing neonatal RDS for term neonates delivered by elective Cesarean section.

Refined frontalis fascial sling with proper lid crease formation for blepharoptosis

Ptosis of the upper eyelid is a complicated problem, and many surgical techniques have been developed for the treatment of ptosis. Frontalis sling with autogenous fascial strip for the correction of severe ptosis with poor levator function is still well accepted. The treatment necessitates an understanding of the etiology of ptosis, detailed history taking, degree of ptosis, the levator function, the anatomic basis of the ptosis and lid crease, and a historic review of surgical procedures. The refinement of our procedure consists of a circular type of frontalis sling with an autogenous fascial strip, harvested from fasciae latae or temporalis fascia, with evenly balanced strength and partial lid resection, including a semilunar segment of skin flap and orbicularis muscle and moderate amount of protruded orbital fat from the orbital septum. The fascial strip is anchored simultaneously to the upper margin of the tarsal plate and incision margin of the pretarsal lid to produce a proper lid crease. This procedure has been successful in the management of 64 lids (46 patients) with a severe degree of ptosis and poor levator function. Satisfactory results have been achieved in 57 lids (89 percent) according to the modified criteria of Berke after an average follow-up period of 18.5 months. Most patients (87.5 percent) have mild lid lag (1 to 3 mm) after the operation, but 58 lids (90.6 percent) achieved a proper lid crease height of 3 to 6 mm.

Intrascar excision for persistent perioral hypertrophic scar

Scar revision is almost a daily work of plastic surgeons, but sometimes it is a challenge to them. Persistent hypertrophic scar in the perioral area is very difficult to treat because of its anatomic location. Many methods of scar removal, including simple scar revision, Z- or W-plasty, V-Y or Y-V flap, local cutaneous flaps, etc., may not be suitable to remove the perioral scar. The specially designed intrascar excision technique is a good method to solve this problem. The long-term follow-up, up to 5 years, in this clinical series revealed that this method does not distort the perioral anatomy and produces satisfactory aesthetic results.

Determination of Z-butylidenephthalide in plasma by high-performance liquid chromatography

An HPLC assay is described for the determination of Z-butylidenephthalide (Z-Bdph) in plasma. Plasma samples were cleaned up by extraction with 2% chloroform in n-hexane. Z-Bdph was separated on a normal-phase silica column with a mobile phase of chloroform-n-hexane (1:1). The limit of quantitation with UV detection at 254 nm for Z-Bdph in plasma was 0.01 microgram/ml. The recovery of Z-Bdph by organic solvent extraction of plasma was 99.5%. The intra-day and inter-day coefficients of variation and relative errors for Z-Bdph determination in plasma were both less than 10%. The present method was applied to pharmacokinetic studies of Z-Bdph in plasma after intravenous administration to rabbits.

Pharmacological stress thallium scintigraphy with 2-cyclohexylmethylidenehydrazinoadenosine (WRC-0470). A novel, short-acting adenosine A2A receptor agonist

BACKGROUND

Pharmacological stress imaging with adenosine or dipyridamole is associated with a high incidence of side effects, including hypotension, chest pain, AV conduction abnormalities, and bronchospasm. Although the desired coronary vasodilatory response is mediated primarily by the adenosine A2A receptors, these side effects result from stimulation of the A1, A2B, or A3 adenosine receptors. We hypothesized that a selective adenosine A2A receptor agonist would induce coronary vasodilatation appropriate for pharmacological stress imaging, without evoking adenosine receptor-mediated side effects.

METHODS AND RESULTS

Infusions of a potent and selective A2A adenosine receptor agonist, WRC-0470 (0.1 to 3 micrograms kg-1. min-1 for 10 minutes), to five open-chest dogs produced dose-related left anterior descending (LAD) and left circumflex (LCx) coronary artery vasodilatation without altering mean arterial pressure, heart rate, left atrial pressure, or left ventricular dP/dt. In the same dogs, adenosine (300 micrograms . kg-1. min-1 for 4 minutes) produced coronary vasodilatation that was limited by significant hypotension. To determine the utility of WRC-0470 for pharmacological stress imaging, the hemodynamic responses to WRC-0470 (0.6 microgram.kg-1.min-1 for 10 minutes) and adenosine (250 micrograms.kg-1.min-1 for 4 minutes) were compared in dogs with critical LAD stenoses. 201T1 was injected at the peak WRC-0470 stress response. WRC-0470 increased LCx flow nearly fivefold but did not significantly lower mean arterial pressure. Anteroseptal defects were readily apparent in slice images from all dogs. The mean defect ratio (LAD/LCx) was 0.59 +/- 0.06.

CONCLUSIONS

The potent A2A-selective adenosine receptor agonist WRC-0470 is a short-acting coronary vasodilator with potential utility for pharmacological stress perfusion imaging.

Comparison between thallium-201 and technetium-99m-tetrofosmin uptake with sustained low flow and profound systolic dysfunction

Technetium-99m-tetrofosmin uptake was compared to that of 201Tl in the setting of low flow and systolic dysfunction.

METHODS

In nine open-chested dogs, a severe left anterior descending (LAD) coronary artery stenosis resulted in a 54.3% mean flow reduction and decreased left ventricular thickening from 21% +/- 1% to -3 +/- 2%. After 30 min, 37 MBq (1 mCi) of 201Tl and microspheres were injected and initial and 2-hr redistribution images acquired. Two hours later, 370 MBq (10 mCi) of 99mTc-tetrofosmin and microspheres were injected and an image was obtained. LAD: left circumflex (LCX) count ratios for both tracers and flows were calculated by well counting postmortem, and 201Tl and 99mTc-tetrofosmin defect magnitudes were determined by quantitative image analysis.

RESULTS

LAD:LCx flow ratios were similar during 201Tl and 99mTc-tetrofosmin injections (0.48 +/- 0.04 versus 0.49 +/- 0.05, p = n.s.). Final 201Tl activity (0.66 +/- 0.04) was significantly higher than 99mTc-tetrofosmin (0.55 +/- 0.05; p < 0.05). LAD/LCx 99mTc-tetrofosmin image defect count ratio was similar to 201Tl defect count ratio on the initial rest 201Tl scan (0.57 +/- 0.03 versus 0.56 +/- 0.02, p = ns), but significantly less than 201Tl defect count ratio at 2 hr (0.57 +/- 0.03 versus 0.65 +/- 0.02, p < 0.05).

CONCLUSION

In a low-flow model with profound systolic dysfunction, myocardial 99mTc-tetrofosmin uptake ( > 50%) reflective of viability was observed in the asynergic zone perfused by the stenotic LAD.

Major burns in pregnancy

From June 1986 to May 1991, there were 1,931 patients to be treated for burns in Linkou Burn Unit, at the Chang Gung Memorial Hospital. Seven patients, aged 24 to 32 years, were pregnant and had burns greater than 10% of total body surface area (TBSA). The severity of the dermal injuries was diagnosed as partial or full thickness. Patient's gestational ages ranged from 8 to 38 weeks. Five patients had normal deliveries at term; one patient had intrauterine fetal death 7 weeks after the burn injury, and one patient had premature labor at gestational age of 33 weeks. Termination of the pregnancy was never done in our series. Active medical treatment together with conservative wound care should be the standard in each trimester of pregnancy.

Positional information within the Mu transposase tetramer: catalytic contributions of individual monomers

The strand cleavage and strand transfer reactions of Mu DNA transposition require structural/catalytic contributions from separate polypeptide domains of individual transposase (MuA) monomers within the functional MuA tetramer. Based on catalytic complementation between two inactive MuA variants, we have derived certain rules by which the physical location of a MuA monomer within the transposition complex specifies its role in DNA breakage and transfer. During strand transfer, MuA monomers contributing domain II to the reaction occupy R1 (the subsite proximal to the strand-transferred nucleotide), while those contributing domain IIIalpha occupy R2. The positions of the monomers contributing these two domains appear to be reversed during DNA cleavage.

Acute lung injury after phosgene inhalation

Phosgene (COCl2) is a colorless oxidant gas which is heavier than air and the lethal exposure dose (LC50) in humans is 500 ppm/min. This gas was originally manufactured as an agent for chemical warfare during World War I and there had been a great deal of studies on phosgene poisoning during the early years of industrial use. It is still widely used in the synthesis of chemicals and plastics. In the modern era, however, phosgene poisoning is relatively uncommon except in accidental exposures. In Korea, there has been no report about lung injury from phosgene inhalation. We present a clinical experience with six patients accidentally exposed to phosgene.

Glycosylation of lipoprotein lipase in human subcutaneous lipomas

Glycosylation of lipoprotein lipase (LPL) was studied in human subcutaneous lipomas. Heparin-releasable LPL activities were higher in lipomas than those in adjacent normal adipose tissues, and showed good correlation with cellular LPL protein mass. Molecular weight of LPL subunit was 57 kDa in both tissues. After endoglycosidase H-digestion, two types of LPL subunits were found in normal adipose tissues; partially sensitive (55 kDa) and totally sensitive (52 kDa) form. In lipoma tissues, the fraction of partially sensitive form (55 kDa) was increased comparing with control adipose tissues. These results suggest that partially sensitive subunits constitute the major secretable form of LPL in human subcutaneous lipomas.

[Adherence of the surface protein P(1) of Streptococcus mutans MT(6)R(Serotype C).]

In this study,the surface protein P(1) of Streptococcus mutans MT(6)R(Serotype C) was extracted from the culture supernants,purified by PAGE,identified by the standard antisera and labelled by with (131)I.The adherence of (131)I protein P(1)((131)I-P(1)) to the saliva-coated hydroxyaptite (S-HA) of the CF (caries-free,22,DFS=0) were studied.The adhesion of (131)I-P(1) to the S-HA promoted a greater extent than that to the HA treated with buffer and bovine serum albumin(P<0.01).This result suggested that protein P(1) may be one of the important adhesins of S.mutans.

Enhancer-independent variants of phage Mu transposase: enhancer-specific stimulation of catalytic activity by a partner transposase

Assembly of the functional tetrameric form of phage Mu transposase (A protein) requires specific interactions between the Mu A monomer and its cognate sequences at the ends of the Mu genome (attL and attR) as well as those internal to it (the enhancer element). We describe here deletion variants of Mu A that show enhancer-independence in the assembly of the strand cleavage complex. These deletions remove the amino-terminal region of Mu A required for its interactions with the enhancer elements. The basal enhancer-independent activity of the variant proteins can be stimulated by a partner variant harboring an intact enhancer-binding domain. By exploiting the identical att-binding, and nonidentical enhancer-binding specificities of Mu A and D108 A (transposase of the Mu related phage D108), we show that the stimulation of activity is enhancer-specific. Taken together, these results suggest that the domain of Mu A that includes the enhancer-interacting region may exert negative as well as positive modulatory effects on the strand cleavage reaction. We discuss the implications of these results in the framework of a recent model for the assembly of shared active sites within the Mu A tetramer.

Non-ketotic hyperosmolar coma complicating steroid treatment in childhood nephrosis

Two nephrotic children treated with prednisone developed steroid-induced diabetes and non-ketotic hyperosmolar coma (NKHC). Both patients presented with convulsions, coma and shock. The glucose concentration of the cerebrospinal fluid was 425 mg/dl and 622 mg/dl, respectively. Both patients had no diabetic family history, but had been treated with prednisone for 4 and 8 months, receiving total doses of 6.6 and 10.8 g, respectively. Despite conventional therapy, both patients deteriorated rapidly and died several hours later. Steroid-induced diabetes associated with NKHC is a rare but serious complication of steroid therapy.

A domain sharing model for active site assembly within the Mu A tetramer during transposition: the enhancer may specify domain contributions

The functional configuration of Mu transposase (A protein) is its tetrameric form. We present here a model for the organization of a functional Mu A tetramer. Within the tetramer, assembly of each of the two active sites for Mu end cleavage requires amino acid contributions from the central and C-terminal domains (domains II and III respectively) of at least two Mu A monomers in a trans configuration. The Mu enhancer is likely to function in this assembly process by specifying the two monomers that provide their C-terminal domains for strand cleavage. The Mu B protein is not required in this step. Each of the two active sites for the strand transfer reaction is also organized by domain sharing (but in the reverse mode) between Mu A monomers; i.e. a donor of domain II (also the recipient of domain III) during cleavage is a recipient of domain II (and the donor of domain III) during strand transfer. The function of the Mu B protein (which is required at the strand transfer step) and that of the enhancer element may be analogous in that their interactions with Mu A (domain III and domain I alpha respectively) promote conformations of Mu A conducive to strand cleavage or strand transfer.

Characterization of daytime sleepiness and psychomotor performance following H1 receptor antagonists

BACKGROUND

While first generation H1-receptor antagonists are widely used, there are relatively few data describing their comparative effects on subjective daytime sleepiness and psychomotor performance.

OBJECTIVE

To compare the effects of first generation H1 receptor antagonists on subjective daytime sleepiness and psychomotor performance.

METHODS

We conducted two single-dose, cross-over studies. In the first, we validated our methodology in 18 healthy subjects by examining the response to diphenhydramine (50 mg), terfenadine (60 mg), and placebo. In the second trial, we evaluated the relative effects following diphenhydramine (50 mg), diphenhydramine (25 mg), chlorpheniramine (4 mg), and placebo. Psychomotor tests included choice reaction time, hand steadiness, and a test that divided attention between tracking and reaction time. Introspective drowsiness was measured using a visual analog scale and the Stanford Sleepiness Scale. Assessments were made prior to dosing and at one, three, and five hours after dosing; a 7-hour post-drug assessment was included in the second trial.

RESULTS

In the first trial, 50 mg diphenhydramine produced significant impairment relative to placebo in both subjective and objective assessments (P < .05). Responses following terfenadine did not differ from placebo. In the second study, all three regimens produced subjective and objective soporific effects to a significantly greater degree than placebo. For example, significant introspective sleepiness was noted three hours following all three regimens (P < .05) and slower choice reaction times were noted one and three hours after dosing (P < .05). The general rank order of effects was diphenhydramine (50 mg), followed by diphenhydramine (25 mg), followed by chlorpheniramine (4 mg). Significant differences among the three regimens were, for the most part, confined to greater soporific effects from diphenhydramine relative to chlorpheniramine (P < .05).

CONCLUSIONS

Taken together, our observations confirm that subjective and objective measures of sleepiness and psychomotor performance occur following single doses of diphenhydramine and chlorpheniramine, but not terfenadine. Differences in soporific effects do exist among regimens of first-generation compounds.

Glycosylation, dimerization, and heparin affinity of lipoprotein lipase in 3T3-L1 adipocytes

The relationship between glycosylation, dimerization, and heparin affinity of lipoprotein lipase (LPL) was studied in 3T3-L1 adipocytes. Three forms of LPL subunits were found in normal cells; totally endo H-resistant (57 kDa), partially sensitive (54 kDa), and totally sensitive (51 kDa) forms. LPL in normal cells was active, dimeric, and showed high affinity for heparin. LPL in cells treated with tunicamycin, preventing the transfer of N-linked oligosaccharide chain, was unglycosylated (51 kDa) and inactive. LPL proteins were found as an aggregate, and had low affinity for heparin. After treatment with castanospermine, an inhibitor of ER glucosidase I, 80% of LPL activity was inhibited. Most of LPL proteins were totally endo H-sensitive, present as an aggregate, and had low affinity for heparin. LPL in cells treated with deoxymannojirimycin, an inhibitor of Golgi mannosidase I, was active, dimeric, and had high affinity for heparin as in normal cells. But LPL subunits were all endo H-sensitive. These results suggest that core glycosylation and subsequent removal of glucose residue is required, but processing after Golgi mannosidase I is not necessary for dimerization and acquisition of high heparin affinity of LPL.

Frozen preservation of human amnion and its use as a burn wound dressing

A method of freezing and sterilizing the human amnion enabled it to be stored at -60 degrees C for more than six months. The membranes were obtained from twenty-four cesarean section mothers without a history of endometritis, premature rupture of their membranes or a positive serology. The elongation and break strength of the membranes were evaluated before and after storage. The membranes as prepared have been utilized on twenty-two wounds of ten burn patients. The results indicate that amnion is quite safe and effective as a biological dressing using this preservation method.

[Preliminary clinical study on prevention of bone loss in postmenopausal women with kidney invigoration]

The effect of Bushen Migu Ye (BSMGY) on preventing the bone loss in postmenopausal women was observed. 43 healthy women with the menopause within 5 years were randomly divided into the treated and control groups, which were basically similar in age and menopausal time. BSMGY and Rhizoma Dioscoreae decoction was given orally in two groups. Some biochemical parameters related to bone metabolism, serum estradiol and forearm bone density were taken before and after treatment. The results showed that 5 months after BSMGY treatment, the ulnar and radial bone mineral content was higher than that of pretreatmental value (P < 0.05), while in control group this index was continually decreased. The change in bone density were also significant different (P < 0.05). It seems that BSMGY is able to prevent the bone loss in postmenopausal women. In the treated group, ratio of fasting urinary calcium and hydroxyproline to creatinine was lower than that of before treatment and the control group (P < 0.05); the concentration of serum alkaline phosphatase had no significant difference (P < 0.05). This preliminary study suggested that one of the therapeutic mechanism of BSMGY was probably due to declining of bone resorption, without affecting the bone formation in postmenopausal women.

Electrical injury--clinical report of 67 cases

We have reviewed 67 patients of electrical burns treated at Linkou Burn Center of Chang Gung Memorial Hospital from January 1988 to April 1992. There were 2086 acute burn admissions during this period with the proportion of electrical injuries being 3.2%. Their age ranged from 13 to 68 years, with 61% in the age group of 20 to 40 years. Sixty-two (92.5%) of our patients were males. Over 60% of these injuries were work-related. The proportion of high voltage electrical injuries was over 60% in our series. All deceased patients and those patients with major complications were in the high voltage electrical injuries group. Low voltage injuries did not leave any major sequelae. In a mean follow-up of 2 years, 83% of our patients could return to the previous job or change to another work. The overall mortality was 6%.

Reverse dorsometacarpal flap in digits and web-space reconstruction

Skin defects in some areas of the digits are difficult to reconstruct, such as the ulnar aspect of the little or ring finger, radial aspect of the index, dorsal or volar aspect of fingers with proximal interphalangeal or metacarpophalangeal joint involvement, and proximal phalanx of the thumb. Moderate or severe contracture of the web space and multiple finger injuries without an available cross-finger flap are also a challenge to reconstructive surgeons. The reverse dorsometacarpal flap presents an option for reconstruction because of these difficulties. It is reliable and versatile in design. The donor site can be closed primarily provided the flap is less than 2 cm wide.

Electrical burns associated with head injuries

Although electrical burns account for a small portion of all thermal injuries, their treatment becomes more complex when associated with injuries of other organs. From July 1987 through December 1991, 8 of 249 burned patients sustained electrical burns associated with head injuries. The mean total body surface area burned was 19% (range, 2%-45%). Computed tomographic (CT) scans of the brain revealed that six patients with moderate to severe head injuries had intracranial hemorrhage including three cases of intracerebral hematoma and another three cases of epidural hematoma. Half of these patients underwent surgical intervention for removal of intracranial hematomas and a compound depressed fracture segments of the skull, and the others were treated conservatively. All the patients progressively recovered consciousness with Glasgow Coma Scale scores of 14 or more and minimal neurologic sequelae. The combination of early detection and prompt removal of life-threatening intracranial hematomas with aggressive support of electrical victims who appear dead would minimize the morbidity and mortality in patients with electrical burns and head injuries.

Inhibition of 3'azido-3'deoxythymidine-resistant HIV-1 infection by dehydroepiandrosterone in vitro

Human immunodeficiency virus type 1 (HIV-1) isolated from patients with acquired immunodeficiency syndrome (AIDS) shows resistance to 3'azido-3'deoxythymidine (AZT) after one or two years of treatment. AZT also has significant toxic side effects, further limiting its use in the therapy of HIV-1-infected individuals. Dehydroepiandrosterone (DHEA) has been shown to have a broad spectrum of biological functions, to be bioavailable orally and to be relatively nontoxic. Epidemiological studies provide evidence that reduced serum levels of DHEA are related to the progression of AIDS in HIV-1 infection. DHEA has also been shown to inhibit HIV-1 replication in vitro and block HIV-1 reactivation from chronically infected cell lines. However, there have been no reports on the ability of DHEA to inhibit the replication of AZT-resistant strains of HIV-1. We investigated whether DHEA treatment could inhibit replication of AZT-resistant strains of HIV-1. Addition of DHEA to MT-2 cell cultures infected with either AZT-sensitive or AZT-resistant isolates of HIV-1 resulted in dose-dependent inhibition of HIV-1-induced cytopathic effect and suppression of HIV-1 replication as measured by accumulation of reverse transcriptase activity. At a concentration as low as 50 microM, DHEA reduced AZT-resistant HIV-1 replication over 50 percent as measured by cytopathic effect and accumulation of reverse transcriptase activity. This study provides evidence that DHEA can inhibit the replication of AZT-resistant as well as wild-type HIV-1. Since the main targets for DHEA are metabolic and cellular signaling pathways leading to HIV-1 replication-activation, DHEA should be effective against multidrug-resistant strains of HIV-1. Combined with recently discovered immunoregulatory properties, the finding that DHEA is able to inhibit replication of both wild-type and AZT-resistant HIV-1 suggests that in vivo DHEA may have a much broader spectrum of action than originally anticipated.

Enhanced tuberoinfundibular dopaminergic neuron activity in thyroidectomized, ovariectomized and estrogen-treated rats with hyperprolactinemia

The involvement of the tuberoinfundibular dopaminergic (TIDA) neurons in the genesis of hyperprolactinemia in female thyroidectomized rats treated with estrogen was the focus of this study. Rats that were ovariectomized (3 weeks), thyroidectomized (2 weeks) and treated with estrogen for 6 days had a 5- to 10-fold increase in serum prolactin (PRL) levels, while the rats receiving the same treatments but without estrogen had lower PRL levels. The activity of TIDA neurons, using dihydroxyphenylacetic acid (DOPAC) concentration or the DOPAC/dopamine (DA) ratio in the median eminence (ME) as an index, was increased and decreased in estrogen-treated and untreated rats, respectively. The increases in serum PRL level and the activity of TIDA neurons were dependent on the duration of thyroidectomy and could both be lowered by daily injection of thyroid hormone (20 or 100 micrograms/kg b.w. thyroxine, i.p.) for 12 days in a dose-dependent manner. Using dihydroxyphenylalanine (DOPA) accumulation in the ME as another index, we also found an increased DOPA/DA ratio in estrogen-treated hypothyroid rats, which effect could be reversed by replacement of thyroid hormone. Furthermore, treatments with bromocryptine (3 mg/kg b.w./day, s.c.) for 3 days or with cysteamine (100 mg/kg b.w., s.c.) at 26, 15 and 2 h before the rats were sacrificed lowered both serum PRL level and TIDA neuron activity. Since PRL can exert a short-loop feedback control on its own secretion, these results indicate that the increased serum PRL levels in estrogen-treated hypothyroid female rats should be the cause, but not the result, of the increased activity of TIDA neurons.

Effect of supernatant of peripheral blood mononuclear cells from nephrotic patients on the sulfated compound synthesis by cultured glomerular epithelial cell

To identify the role of circulating immune factor(s) in the development of proteinuria, the supernatant of peripheral blood mononuclear cells (PBMC) were obtained from 15 patients with steroid-responsive nephrotic syndrome, and its effect on the synthesis of sulfated compound by cultured rat glomerular epithelial cell (GEC) were studied by 35S, 3H-leucine dual-isotope labelling technique. The result showed that the supernatant of PBMC from 9 patients without steroid treatment increased 35S uptake in GEC (P < 0.01), while there was no significant difference in 35S uptake between the 6 patients treated with prednisone (1.5-2.0 mg/kg.d-1) and 6 normal controls.

Inhibition of HIV-1 latency reactivation by dehydroepiandrosterone (DHEA) and an analog of DHEA

The initial infection with human immunodeficiency virus type 1 (HIV-1) in most individuals usually results in the establishment of a latent or chronic infection before eventual progression toward acquired immunodeficiency syndrome. HIV-1 can also establish a latent or persistent infection in some T cell lines that show minimal constitutive virus expression. However, activation of the T cell lines leading to enhanced HIV-1 replication can be induced by antigens, mitogens, and cytokines (tumor necrosis factor alpha [TNF-alpha], interleukin 1, and interleukin-2). Various gene products from other viruses (HTLV-1, HSV, EBV, CMV, HBV, and HHV-6) can also enhance HIV-1 long terminal repeat (LTR)-driven reporter gene activity. On the basis of these observations, it has been proposed that reactivation of latent HIV-1 harbored in chronically infected T lymphocytes, monocytes, or macrophages plays an important role in the pathogenesis of AIDS. So far, there are no drugs or therapy available that can provide protection against HIV-1 latency reactivation. ACH-2, derived from a human T cell line (CEM), is chronically infected with HIV-1, with low levels of constitutive virus expression. ACH-2 can be converted to productive infection by stimulation of the cells with 12-O-tetradecanoylphorbol-13-acetate (TPA), mitogen or cytokines (TNF-alpha), or infection with HSV. Therefore the ACH-2 cell line is a good candidate for studying the effects of drugs on HIV-1 activation. Previously, we have reported that DHEA and synthetic analogs of DHEA can be modest inhibitors of HIV-1 IIIB replication in phytohemagglutinin-stimulated peripheral blood lymphocyte cultures.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of combined therapy of traditional Chinese and Western medicine on C-reactive protein in post-debridement patients]

Closely monitoring whether the secondary infection in the patients of post-debridement occurred or not and appropriately treating these patients were the important ways to reduce the incidence of infection. Through estimating the level of the serum C-reactive protein (CRP) as the monitoring index of infection, dynamically observed the effect of the combined traditional Chinese and Western medicine therapy (TCM-WM) on CRP after debridement, as was compared with the effect of the Western medicine therapy (WM) group in which only the WM was administrated. The result showed that the levels of CRP decreased in both TCM-WM and WM group on 4th day after the operation, but the level of CRP in former group was lower than that in latter one, the difference was very significant (P < 0.001). So that, it was assumed that TCM-WM significantly excelled the WM on affecting the level of CRP and reducing the incidence of infection. It was suggested that CRP could be used as an effective and objective index to determine whether the secondary infection has happened and to assess the efficacy of some drugs.