Relationship between human parvovirus B19 infection and aplastic anemia

OBJECTIVE

To explore the relationship between human parvovirus B19 (HPV B19) infection and aplastic anemia (AA) and to investigate the role of HPV B19 in the occurrence of AA.

METHODS

The presence of HPV B19 DNA was detected in the peripheral blood samples of 60 patients with AA (children 38 and adults 22) by nested polymerase chain reaction (PCR) assay, and 30 healthy persons were selected as control.

RESULTS

Sixteen (26.7%) of 60 AA cases were HPV B19 DNA positive, while all the samples in the control group were negative for HPV B19 (P = 0.000914). Among the case group, the positive rates of HPV B19 DNA were 21.4% (6/28), 30.0% (3/10), 20.0% (1/5) and 35.3% (6/17) in children acute AA (AAA), children chronic AA (CAA), adults AAA and adults CAA patients respectively, which were significantly higher than that in the control group. Furthermore, there was no remarkable difference between children AA and adults AA in the 16 HPV B19 DNA positive patients; neither was there between AAA and CAA.

CONCLUSION

HPV B19 infection is not only correlated with the occurrence of children AAA and CAA, but also with adults AAA and CAA, and might be an important viral cause for AA in humans.

The metabolism of fatty acids in human Bietti crystalline dystrophy

PURPOSE

To investigate the role of abnormal lipid metabolism in Bietti crystalline dystrophy.

METHODS

Cultured human lymphocytes and fibroblasts from patients with Bietti crystalline dystrophy (BCD) were incubated in the presence of [(14)C]18:3n-3 or [(14)C]18:2n-6. Incorporation into the cellular lipid pools and further metabolism by desaturation or elongation were monitored by thin-layer chromatography and HPLC. Results were compared with those in normal control subjects and patients with Wolman disease (WD).

RESULTS

Pulse-chase experiments with labeled fatty acids in all groups showed that, after 1 hour, radioactivity was largely confined to the triacylglyceride (TG) and choline phosphoglyceride (CPG) pools. However, after several hours, radioactivity was transferred from the TG and CPG pools, some going to the serine and ethanolamine phosphoglyceride (SPG and EPG) pools. Fibroblasts from all groups showed direct transfer of fatty acids (FAs) into CPG and EPG. Incorporation of labeled FAs into the EPG pool paralleled extensive desaturation and elongation of 18:2n-6 to 22:5n-6 and 18:3n-3 to 22:6n-3. Fibroblasts from patients with WD (a lysosomal acid lipase deficiency characterized by excessive lipid accumulation), showed higher incorporation of 18:2n-6 into TGs than did normal or BCD fibroblasts. Conversely, fibroblasts from patients with BCD showed lower conversion of 18:3n-3, but not of 18:2n-6, into polyunsaturated FAs (PUFAs) than those of normal subjects or patients with WD. This was true for total FAs, CPGs, and EPGs. Similar results were found in both fibroblasts and lymphocytes; however, unlike fibroblasts, lymphocytes from normal subjects showed similar levels of incorporation of FAs into EPGs and CPGs. In contrast, incorporation of 18:3n-3 into EPGs was decreased in lymphocytes from patients with BCD.

CONCLUSIONS

BCD is characterized by a lower than normal conversion of FA precursors into n-3 PUFA, whereas there is a higher than normal level of n-6 and n-3 FAs incorporation into TGs in cells from patients with WD. These findings raise the possibility that abnormal lipid metabolism associated with BCD is the result of deficient lipid binding, elongation, or desaturation in contrast to the lysosomal acid lipase deficiency found in Wolman disease.

Pretreatment surgical lymph node staging predicts results of trimodality therapy in esophageal cancer

OBJECTIVE

Prediction of responders to induction therapy in esophageal cancer (EC) patients is important. In this study, we evaluated the role of thoracoscopic/laparoscopic (Ts/Ls) staging in prediction of treatment response and survival in EC patients with trimodality treatment.

METHODS

Retrospective study of EC patients who had undergone Ts/Ls staging and received trimodality treatment at the University of Maryland Medical Center and the Baltimore Veterans Administration Hospitals from July, 1991 to December, 1999. Preoperative therapy consisted of concurrent chemotherapy (5-FU + cisplatinum) and radiotherapy.

RESULTS

Forty-four EC patients who underwent pretreatment Ts/Ls staging during the study period were able to complete concurrent chemoradiotherapy followed by surgical resection. There were 36 men and 8 women aged 40 to 77 (median age 62). Twenty-seven (61.4%) patients were found to have lymph node metastasis by surgical staging. Fourteen patients (31.8%) had a pathologic complete response. Patients with positive lymph nodes had a lower response rate than those with negative lymph nodes (14.8% vs. 58.8%, P=0.006). Other clinicopathologic features including gender, weight loss, clinical TNM stage, surgical T stage, and histology did not correlate with treatment response. Univariate analysis showed that weight loss and treatment response were important prognostic factors for disease-free survival (P=0.01 and P=0.02, respectively). Histology, surgical N stage and surgical TNM stage appeared to be associated with prognosis (P=0.067-0.097). Multivariate analysis revealed that only surgical N status and weight loss were significant prognostic factors (P=0.05, and P=0.006, respectively).

CONCLUSIONS

Surgical Ts/Ls staging provides accurate evaluation of tumor spread in EC patients. Pretreatment N status was the single most important predictor of response to induction treatment as well as a reliable prognosticator of survival.

[An experimental study on the construction of composite graft with epithelia and fibroblasts on collagen sponge]

OBJECTIVE

Primarily cultured human epithelia and fibroblasts were inoculated on collagen sponge to construct composite skin substitute.

METHODS

Epithelia and fibroblast asts from human foreskin were primarily cultured. Fibroblasts (1 x 10(5)/cm(2)) were inoculated on collagen sponge after digestion and cultured for 3 days prior to inoculation of epithelial cells (2 x 10(5)/cm(2)) to construct composite skin grafting substitute, and it was then grafted onto full skin loss (FSL) wounds of nude mice. Collagen sponge membrane lacking cell inoculation was used as control. The wound healing was evaluated by measuring the residual wound area. Tissue samples were harvested and examined by means of histology, immunohistochemistry and electron microscopy.

RESULTS

Epithelia and fibroblasts could be cultured in vitro on the carrier collagen sponge. After being grafted onto the wound, the epithelia and fibroblasts wound further proliferated and differentiated. The composite skin could stick to the carrier fairly well. There exhibited less epidermal scar proliferation and satisfactory contour of the neoskin. Integral basal membrane of the skin could be identified by immunohistochemical staining. The quality and speed of wound healing with the composite skin substitute were superior to that with collagen sponge only.

CONCLUSION

The composite grafts constructed by epithelia and fibroblasts on collagen sponge could be a potential neotype composite skin substitute for the repair of FSL.

Immunohistochemical localization of interleukin-2 and its receptor subunits alpha, beta and gamma in the main olfactory bulb of the rat

Endogenous interleukin-2 (IL-2) was found in the adult rat brain, however, it has not been reported whether this cytokine is present in the olfactory bulb. Immunohistochemical techniques were used to examine the cellular localization of IL-2 and its receptor subunits in the main olfactory bulb of the rat. Strong IL-2 immunoreactivity was localized in glial cells, specifically in the olfactory nerve layer, glomerular layer and external plexiform layer. IL-2 mRNA was detected in the olfactory bulb by RT-PCR. All three IL-2 receptor subunits also showed distinct laminar distributions. The IL-2Ralpha and IL-2Rbeta immunoreactivity was found both in neurons and glial cells, whereas IL-2Rgamma imunoreactivity was found in glial cells, and thus resembled IL-2 immunostaining. The present results demonstrated a wide distribution of IL-2 and its receptor subunits in the main olfactory bulb of the rat, suggesting that IL-2 might play a role in the olfactory function through autocrine or paracrine pathways. The exclusive high expression of IL-2 in glial cells in distinct laminar structures, where neuron-glia interactions are closely associated with olfactory nerve regeneration, imply that IL-2 might be involved in the process of nerve regeneration in the olfactory bulb.

[Cloning and expression of Shiga-like toxin type II variant B gene of E. coli]

A structure sequence and a DNA fragment including the signal peptide sequence and structure sequence of Shiga-like toxin II variant B subunit gene were amplified from E. coli strain O138 by PCR. After digested with restriction endonuclease EcoRI and BamHI, the two genes were orientally inserted into the polycloning site of expression vector pYA3334 (asd+) respectively. Recombinant plasmids pB0 and pB1 were constructed and amplified in E. coli X6212 (asd-). pB0 and pB1 were then introduced into avirulent Salmonella typhimurium vaccine strain X4550 (asd-) by serial transformation through intermediate strain X3730 (asd-) to construct recombinant SLT-IIvB strain. Results of nucleotide sequencing of the cloned fragments in pB0 and pB1 revealed that they were in correct ORF of SLT-IIvB. The results of SDS-PAGE and Western-blot showed that 7.6 kD protein of SLT-IIvB antigen was expressed at pretty high level in recombinant strain X4550(pB0). The results of mice immunization indicated X4550(pB0) could initiate the host to produce specific antibodies to SLT-IIvB and LPS-O antigen of X4550. So the recombinant strain X4550 (pB0) is worth considering as a candidate vaccine strain against porcine edema disease and Salmonella typhimurium infections.

Thoracoscopic sympathectomy

The objective was to evaluate the safety and effectiveness of endoscopic thoracic sympathectomy (ETS) for treatment of a variety of sympathetic disorders, including hyperhidrosis, splanchnic pain, reflex sympathetic dystrophy, and Raynaud upper extremity ischemia. Sixty-three ETS procedures were performed in 34 patients at the University of Maryland Medical System between March 1992 and August 1999 (14 male patients, 20 female patients; mean age 22 years). The indications for surgery were hyperhidrosis in 26 patients, upper extremity ischemia in 3 patients, splanchnic pain and reflex sympathetic dystrophy in 2 patients each, and facial blushing in 1 patient. Preoperative symptoms resolved completely or improved significantly in 97.1% (33/34) of patients. One patient with left reflex sympathetic dystrophy had symptoms that recurred shortly after surgery. There were no major complications; one patient with hyperhidrosis reported significant compensatory hyperhidrosis. These findings suggest that ETS is a safe and effective procedure for treatment of a variety of sympathetic disorders. Its application for hyperhidrosis is very effective, and its treatment of splanchnic pain, reflex sympathetic dystrophy, and Raynaud syndrome are rewarding. With increasing experience, ETS should become established in the repertoire of the thoracic surgeon.

Thoracoscopic and laparoscopic staging for esophageal cancer

Accurate pretreatment staging for patients with esophageal cancer (EC) is becoming increasingly important in the evaluation and comparison of different treatment modalities. Noninvasive staging methods are imperfect in detecting lymph node metastasis in patients with EC. Surgical staging with the thoracoscopic/laparoscopic (Ts/Ls) technique may provide accurate staging information that is useful for evaluating and comparing the results of clinical trials of preoperative chemotherapy and radiotherapy. It can be used to confirm or exclude suspicious distant metastasis found by other staging methods. Pretreatment (lymph node) biopsies obtained by Ts/Ls staging allow further molecular biologic analysis to detect occult lymph node metastasis for more accurate lymph node staging. Since 1992, we have used Ts/Ls staging for EC in 111 patients. We found that Ts/Ls is a promising method for staging lymph nodes in EC patients. A recent study showed that pretreatment surgical lymph node staging can predict response and survival for EC patients receiving trimodality treatment (ie, radiation, chemotherapy, and surgery). The information obtained with surgical staging now offers us the opportunity to optimize therapy to specific patient groups based on the extent of disease at the time of initial presentation. Nevertheless, unlike the practice of mediastinoscopy in lung cancer patients, Ts/Ls staging in EC patients remains an academic interest rather than a clinical practice. The concept of accurate pretreatment staging of EC remains to be realized and accepted in the clinical community.

Use of minimally invasive surgery in staging esophageal cancer

Noninvasive staging of esophageal cancer (EC) is often inaccurate, and this fact has compromised clinical trials of treatment for EC. Prognostic evaluation might allocate chemotherapy and radiation more appropriately. Thoracoscopy and laparoscopy has recently shown promising results, and molecular analysis of the recovered tissue may further improve staging accuracy.

Pleural lavage cytology in esophageal cancer without pleural effusions: clinicopathologic analysis

OBJECTIVE

The literature of pleural lavage cytology (PLC) is focused on lung cancer. We conducted this pilot study to determine the incidence of malignant pleural cytologies in patients without pleural effusions who undergo curative resection for esophageal cancer, and to evaluate the clinicopathologic significance of positive cytology.

METHODS

Forty-eight patients underwent esophagectomy for thoracic esophageal cancer in our unit from January 1998 to January 1999. After thoracotomy, pleural lavage was performed before any intrathoracic manipulation and cytologically evaluated.

RESULTS

There was one patient with stage I, 27 patients with stage II, and 20 patients with stage III cancer of the thoracic esophagus. The mean age was 55 years (range 41-77 years). Fifteen cases (31.3%) were found to have positive lymph nodes (N1). Squamous cell carcinoma was the dominant histopathologic type (91.7%). Positive lavage cytology in the whole group was found in 18.8% (9/48). There was no significant correlation to gender, age, clinical symptoms, histology, T or N status, TNM stage, or tumor location.

CONCLUSIONS

The incidence of positive pleural lavage cytology in esophageal cancer is disconcertingly high. Positive cytology might suggest a more aggressive tumor biology. Future studies on its relation to survival and occult lymphatic metastasis are warranted.

[The relationship between operation on gastrointestinal cancer and single cells metastasis via portal vein]

OBJECTIVE

To confirm the effect of radical operation on single cells metastasis of gastrointestinal cancer.

METHODS

One hundred and seventy two patients with gastrointestinal cancer were divided randomly into group I (111 cases, ordinary operation) and group II (61 cases, operation after ligation of drained vessels). Catheters were inserted into the portal vein during operation. Blood was aspirated and contrifugated. Anti-EMA monoclonal antibody marked the cancer cells, which were shown by ABC immunohistochemical staining.

RESULTS

In the examinate group, 72 cases of gastrointestinal cancer were found positive cells among 111 cases (positive rate 64.9%). In the control group, 61 cases were tested and 13 cases were found positive cells (positive rate 21.3%) with a highly significant difference between the two groups (P < 0.005).

CONCLUSIONS

Ligating the relative blood vessel before the radical operation can prevent single cancer cells from metastasis via portal vein.

Thermodynamic parameters for an expanded nearest-neighbor model for formation of RNA duplexes with Watson-Crick base pairs

Improved thermodynamic parameters for prediction of RNA duplex formation are derived from optical melting studies of 90 oligoribonucleotide duplexes containing only Watson-Crick base pairs. To test end or base composition effects, new sets of duplexes are included that have identical nearest neighbors, but different base compositions and therefore different ends. Duplexes with terminal GC pairs are more stable than duplexes with the same nearest neighbors but terminal AU pairs. Penalizing terminal AU base pairs by 0.45 kcal/mol relative to terminal GC base pairs significantly improves predictions of DeltaG degrees37 from a nearest-neighbor model. A physical model is suggested in which the differential treatment of AU and GC ends accounts for the dependence of the total number of Watson-Crick hydrogen bonds on the base composition of a duplex. On average, the new parameters predict DeltaG degrees37, DeltaH degrees, DeltaS degrees, and TM within 3.2%, 6.0%, 6.8%, and 1.3 degreesC, respectively. These predictions are within the limit of the model, based on experimental results for duplexes predicted to have identical thermodynamic parameters.

Identification, isolation, and characterization of a 32-kDa fatty acid-binding protein missing from lymphocytes in humans with Bietti crystalline dystrophy (BCD)

Bietti crystalline dystrophy (BCD) is an autosomal recessive retinal degeneration characterized by intraretinal lipid inclusions with degeneration of the retina and sclerosis of the choroidal vessels, resulting clinically in progressive night blindness and constriction of the visual fields. Characterization of fatty acid metabolism in Bietti crystalline dystrophy suggested that BCD might result from abnormalities in lipid-binding proteins or one or more enzymes active in fatty acid elongation and desaturation. To further investigate the first possibility, the docosahexaenoic acid-binding proteins (DHABPs) of human lymphocytes from patients with Bietti crystalline dystrophy were studied and compared with those of normal controls. For fatty acid-binding protein (FABP) identification, lymphocyte cytosol was first subjected to Lipidex 1000 chromatography. FABPs were then cross-linked with [14C]22:6n-3 and identified by HPLC and SDS-PAGE. Ten major peaks corresponding to calculated molecular weights of 13, 14, 32, 43, 45, 50, 64, 96, 105, and 186 kDa exhibit high-affinity binding of fatty acids. Significantly, peaks corresponding to two fatty acid-binding proteins of 32 and 45 kDa present in age-matched controls are absent from lymphocytes of patients with BCD. The 32-kDa fatty acid-binding protein present in normal individuals but absent from patients with BCD was isolated from cultured control human lymphocytes, its fatty acid-binding properties were characterized, and its amino acid composition was analyzed. It shows specific binding of 3n-3 fatty acids, consistent with the pattern of abnormalities of lipid metabolism demonstrated in patients with BCD. These results suggest that the 32- and 43-kDa FABPs are reasonable candidates for causing BCD.

[The estrogenic activities of 2-[3-estrone-N-ethyl-piperazine-methyl]tetracycline(XW630)--a new compound with anti-osteoporosis activity]

2-[3-Estrone-N-ethyl-piperazine-methyl] tetracycline (XW630) showing anti-osteoporosis activity is a new compound with piperazine-tetracycline in the steroid structure of estrone. The affinity of XW630 with uterine estrogen receptor and its estrogenic activity were studied in this paper. The relative affinities of estrone, estradiol and XW630 with estrogen receptor (ER) of the uterine myoma tissues were found to be 0.325, 1.000 and 0.011, respectively, by the competitive assay. The estrogenic activity index of estrone, estradiol and XW630 were shown to be 9.70, 10.30 and 6.90, respectively, by the uterine weight assay using immature mice. These indexes indicate that: the estrogenic activity of XW630 is about 1/1960 that of estrone and 1/7742 that of estradiol. The vaginal smear assay of oophorectomized mice also showed that the estrogenic activity of XW630 is less than that of estrone and estradiol.

Effect of huoxuequyu recipe on erythrocyte ultrastructure and membrane ATPase activity in rats with passive smoking

The effect of "Huoxuequyu" recipe on erythrocyte membrane Ca(2+)-ATPase activity, Na(+)-K(+)-ATPase activity and erythrocyte ultrastructure in rats exposed to passive smoking were observed. The erythrocyte membrane Ca(2+)-ATPase activity and Na(+)-K(+)-ATPase activity were found to be decreased in the model group as compared with the control group (P < 0.01, P < 0.01), while no significant difference existed between the treated group and the control group (P > 0.05). Our results also showed that there were more deformed red blood cells in model group than in control group under TCM and SEM (P < 0.0001). No significant difference was found between control group and treated group (P > 0.05). Furthermore, these findings indicated that "Huoxuequyu" recipe, a prepared natural herbal medicine, may be involved in modulation of the activity of erythrocyte membrane enzymes, thereby protecting erythrocyte membrane, so as to improve the erythrocyte function.

Effect of sedative and hypnotic doses of propofol on the EEG activity of patients with or without a history of seizure disorders

Propofol is alleged to possess both pro- and anticonvulsant properties, leading to controversy regarding its use in patients with a history of seizures. Since propofol is administered for both sedation and hypnosis, it is important to understand the effects of low (0.5-1.0 mg/kg) and high (2-2.5 mg/kg) doses of propofol on the electroencephalogram (EEG). In this study, the hemodynamic and EEG effects of cumulative doses of propofol from 0.5 to 2.5 mg/kg i.v. were studied in 30 neurosurgical patients with or without a history of seizure disorders. While continuously recording from scalp EEG electrodes (F3, F4, C3, C4, P3, P4, O1, and O2), propofol 0.5 mg/kg was infused intravenously over 20 s. The same dose of propofol was reinjected four times at 2-min intervals, until a total dose of 2.5 mg/kg had been administered. The number and average amplitude of the EEG waves were counted and measured manually, respectively, from 80 to 90 s after beginning the injection of each dose of propofol. After lower propofol doses (0.5-1 mg/kg), the number of beta-waves increased, while alpha- and theta-waves decreased significantly in all patients. However, with larger doses of propofol (total dose of 2-2.5 mg/kg), the number of beta-waves decreased and delta-waves appeared. The amplitudes of all EEG waves increased and were maintained at a higher level after administration of propofol. Spike (or sharp) waves appeared in 33% of the control patients and in 40% of the epileptic group after propofol 0.5 mg/kg and in 73% of the control and 67% of the epileptic patients after the 1.5-mg/kg dose. In the majority of patients, the spike waves disappeared when additional doses of propofol were administered. One patient in the epileptic group had an EEG-recorded and clinical grand mal seizure after propofol 1 mg/kg, but the seizure disappeared after an additional 0.5-mg/kg bolus dose was administered. The propofol-induced EEG changes appeared initially at the frontal and central EEG electrodes and subsequently at the other EEG electrodes. Overall, there were no significant differences in the spectrum of EEG changes between the two patient populations. It is concluded that propofol produces similar dose-dependent effects on EEG activity in patients with or without a history of seizure disorders. While induction of anesthesia with higher doses of propofol (> 1.5 mg/kg) in neurosurgical patients with well controlled seizure disorder is safe, smaller sedative doses should be administered with caution to epileptic patients.

Phase II trial in China of a new, rapidly-acting and effective oral antimalarial, CGP 56697, for the treatment of Plasmodium falciparum malaria

One hundred and two Chinese out-patients with naturally acquired, previously untreated, falciparum malaria were selected to evaluate the efficacy of a new combination anti-malaria therapy, CGP 56697 (artemether plus benflumetol). In this open non-comparative trial each patient received a combination of 80 mg artemether and 480 mg benflumetol given orally at 0, 8, 24 and 48 hours (total: 320 mg artemether, 1,920 mg benflumetol). Patients were kept for 28 days in a transmission-free hospital in an area with chloroquine resistant falciparum malaria to prevent reinfection and to aid diagnosis of recrudescence. Progress and possible adverse effects were monitored by blood film parasitology, blood biochemistry assays, urinalysis, ECG and X-ray. Ninety-eight of the 102 patients were shown to be free of infection at 28 days, a 96.1% cure rate. Parasite reduction at 24 hours was 99.4%. Time to effect complete parasite clearance ranged from 24 to 54 hours (median 30 hours). Time for fever clearance ranged from 6 to 78 hours (median 18 hours). Recrudescence was low (3.9%). No significant adverse side-effects were encountered. It is concluded that CGP 56697, a combination anti-malaria therapy of artemether with benflumetol, offered a rapid and highly effective treatment for acute uncomplicated falciparum malaria in an area of chloroquine-resistant malaria in China.

[A study on neurotoxicity of acrylamide and glycidamide]

Glycidamide (GA) is an epoxide metabolite of acrylamide (AA). Neurotoxicity of both GA and AA was compared by their performance in behavioral, neuro-biochemical and neuropathological studies. Male rats were injected peritoneally with AA (25 or 50 mg/kg) or GA (50 or 100 mg/kg) once daily for eight days. Results showed that toxic effects of AA were greater than those of GA in wheel rotation test, hind limb splay test, and activities of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in peripheral nerves in rats. Results of neuropathological examinations in experimental rats also provided evidence that AA could cause damage to peripheral nerves, but GA did not. It indicated that nerve tissue was more vulnerable to AA than to GA. Also, it suggested that neurotoxic effects of AA was caused by itself, and influenced less by its metabolite GA.

[Spectroscopic investigation of the properties of axial coordination of tailed metalloporphyrins]

The properties of axial coordination of nitrogenous ligands to four tailed metalloporphyrins, O-PyTPPFe ( III ) Cl, O-ImTPPMn ( III ) Cl, O-PyTPPMn ( III ) Cl and O-ImTPPFe ( III ) Cl, has been investigated by UV-Visible spectral techniques. The effects of terminal groups, solvents and metal center were examined and discussed.

The value of cervical mediastinoscopy combined with anterior mediastinotomy in the peroperative evaluation of bronchogenic carcinoma of the left upper lobe

METHODS

From January 1990 to July 1994, 85 patients who were otherwise thought to have an operable tumour within the left upper lobe underwent left anterior mediastinotomy supplemented by cervical mediastinoscopy in 75 cases. This combined approach allowed assessment of nodal involvement within the superior and anterior mediastinal areas, the detection of direct tumour invasion into the mediastinum and the determination of resectability by bidigital examination of the area around the aortic arch and sub-aortic fossa.

RESULTS

It was found that 27 (31.8%) patients were inoperable, either because of nodal involvement at cervical mediastinoscopy (4 patients) or because of extension into the mediastinum at left anterior mediastinotomy (14 patients), or because of positive results from both methods (9 patients). The inoperability determined by this examination for patients with adenocarcinoma (8/18, 44.4%) is higher than for patients with squamous carcinoma (12/52, 23.1%). All of the 58 patients with negative findings proceeded to thoracotomy and complete resection was possible in 54 patients (93.1%).

CONCLUSION

We conclude that this combined approach is better than using either technique alone in the preoperative staging and the evaluation of resectability of left upper lobe tumours.

[Study of the relationship between human quality and reliability]

To clarify the relationship between human quality and reliability, 1925 experiments in 20 subjects were carried out to study the relationship between disposition character, digital memory, graphic memory, multi-reaction time and education level and simulated aircraft operation. Meanwhile, effects of task difficulty and enviromental factor on human reliability were also studied. The results showed that human quality can be predicted and evaluated through experimental methods. The better the human quality, the higher the human reliability.

[Cloning and identification of fliCi gene of Salmonella typhimurium]

Purified Salmonella typhimurium 8705 chromosomal DNA was digested with EcoRI. DNA fragments above 400 bp were obtained by Sepharcyl S-400 chromatography and cloned into vector pGEM-3Zf(-), then transformed into host cell LC2a (hag- is recA-). One out of 6013 transformants was found to be motile and this clone was named pGI4015. Miniprep proved that pGI4015 contained an inserted fragment about 15.3 kb. Motility/inhibition tests as well as Southern blot hybridization showed that pGI4015 bear the H-1i gene of S. typhimurium. With the aid of BamHI and SalI site, sequences unrelated to flagellin in the cloned DNA fragment was removed, and a 3.8kb fragment containing fliC gene was subcloned.

Pericardial repair after extensive resection: another use for the pedicled diaphragmatic flap

BACKGROUND

Extended resection for pulmonary malignancy frequently leaves a large pericardial defect, sometimes associated with resection of the phrenic nerve. On the left the defect does not require repair; as long as the defect is sufficiently large to avoid constriction, the heart can herniate freely. On the right such herniation is associated with venous inflow occlusion and death. The pedicled diaphragmatic flap has been used in other situations in thoracic surgery. We have modified this to allow closure of the pericardial defect and concurrent plication of the denervated diaphragm. It may also be used to cover the bronchial stump or a bronchial anastomosis.

METHODS

The flap has been used in 13 patients over an 11-year period.

RESULTS

Secure closure of the pericardial defect has been achieved in all patients with satisfactory plication of the diaphragm. Reoperation for bleeding was necessary in 3 patients, but in only 1 was the diaphragm shown to be the site of bleeding. Patients otherwise made an uneventful recovery.

CONCLUSIONS

A large pedicled flap of redundant diaphragm provides secure closure for large pericardial defects after extended right pneumonectomy.

Interaction of electron leak and proton leak in respiratory chain of mitochondria--proton leak induced by superoxide from an electron leak pathway of univalent reduction of oxygen

By incubating the isolated rat myocardial mitochondria with xanthine-xanthine oxidase, an exogenous superoxide (O2.-) generating system, and by ischemia-reperfusion procedure of isolated rat heart as an endogenous O2.- generating system, it was found that both sources O2.- showed the same injurious effects on mitochondrial function resulting in (i) increasing proton leak rate, lowering proton pumping activity and H+/2e ratio of respiratory chain, and (ii) decreasing transmembrane potential of energized mitochondrial inner membrane by succinate oxidation. The injurious effects of O2.- on these mitochondrial bioenergitical parameters mentioned above exhibited a dosage- or reaction time-dependent mode. O2.- has no effects on the electron transfer activity and transmembrane potential of nonenergized mitochondria. Being a superoxide scavenger, 3,4-dihydroxylphenyl lactate showed obvious protection effects against damage of both exogenous superoxide sources from xanthine-xanthine oxidase system and endogenous O2.- source from ischemia-reperfused heart on proton pumping activity, H+/2e ratio and transmembrane potential of energized mitochondria. The experimental results presented here clearly showed that O2.- radicals induce an increase of proton leak in mitochondria directly related to the molecular mechanism of early phase damage of ischemia-reperfused heart, and also provide evidence to support our recent proposed hypothesis that electron leakage to oxygen to form O2.- in respiratory chain is one of the mechanical cause of proton leakage in mitochondria.

Noninvasive measurement of protein concentration

At selected magnetic field strengths, protein and water proton spin-lattice relaxation rates are sensitive to the concentration of rotationally immobilized peptide nitrogen because of field dependent heteronuclear cross relaxation coupling between protein proton and nitrogen-14 spins that is carried to the water by proton homonuclear cross-relaxation. Measurement of the water proton spin-lattice relaxation time, or a signal amplitude proportional to it, may provide a noninvasive measure of peptide bond concentration, which provides a direct measure of immobilized protein content in most tissues. The approach using protein gels in two magnetic field strengths is demonstrated. At 66.7 mT; the proton Zeeman energy matches one of the peptide nitrogen transitions dominated by the unaveraged nuclear electric quadrupole interaction; cross-relaxation between the protons and nitrogen-14 is efficient. At 77.5 mT, the proton Zeeman energy is not matched with the nitrogen energy and proton-nitrogen cross-relaxation is not efficient. It is shown that the difference in the water proton spin-lattice relaxation rates on and off the energy level match condition is a linear function of the rotationally immobilized protein concentration.

Soluble-binding proteins for docosahexaenoic acid are present in neural retina

PURPOSE

To determine if soluble binding proteins (BP) for fatty acids (FA), particularly docosahexaenoic acid (DHA), could be identified in the cytosol of rat and bovine retinas under in vitro and in vivo conditions.

METHODS

In vitro, cytosol fractions from normal bovine and rat retinas were delipidated and incubated with [14C]-DHA with or without a number of competing fatty acids. After crosslinking bound FA to BP, the proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and radioactivity determined in each fraction. For in vivo experiments, rats received [14C]-DHA by gavage. At selected periods after ingestion, retinas were collected and cytosolic fractions were prepared from each. These were crosslinked and subjected to SDS-PAGE, and radioactivity was determined in each fraction.

RESULTS

In vitro, several peaks of radioactivity (approximately 13, 20, 32, 43-45, 50, 63, and 94-105 kd) were found that exhibited [14C]-DHA binding. Relative specificity of binding was assessed by blocking of the [14C]-DHA binding with unlabeled DHA and by competition experiments with other FAs. After in vivo ingestion of [14C]-DHA, a large peak of radioactivity was observed at 43 kd by 4 hours. At 6 hours, this peak decreased and, after 24 hours, it approached baseline.

CONCLUSIONS

These findings demonstrate that there is a discrete grouping of proteins in retinal cytosol capable of binding DHA and other FA. Although the identities of these proteins have yet to be determined, the group may include a member of the 12- to 15-kd group of small fatty acid binding proteins (FABP). In particular, a unique 43-kd binding peak could play a major role in the uptake, binding, or both of DHA by the retina in vivo.

Consistent striatal damage in rats induced by 3-nitropropionic acid and cultures of arthrinium fungus

Arthrinium fungi were cultivated from the samples of mildewed sugarcane which caused acute encephalopathy and delayed dystonia in children. The Arthrinium cultures (AC) contained 5 mg/ml 3-nitropropionic acid (3-NPA) after being inactivated and concentrated. A neuropathological study was carried out in rats intoxicated with 3-NPA and AC, respectively. Consistent bilateral striatal necrosis was found in rats with both poisonings, and the severity was well correlated with persistent recumbency which was a clinical indicator of the development of morphological brain lesions. A reproducible animal model of striatal damage has been produced in rats by IP injections of 10 mg/kg 3-NPA, 6 times a day, with an interval of 1.5 h for 3-5 days. The clinical and neuropathological manifestations in rats dosed with AC were nearly the same as those dosed with 3-NPA. The striatal lesions induced by 3-NPA and AC in poisoned rats were in accordance with the bilateral lenticular hypodensity found by CT scanning in patients of mildewed sugarcane poisoning with delayed dystonia. This neuropathological evidence supports previous epidemiological and mycological findings which indicate that 3-NPA is the possible pathogen of acute mildewed sugarcane poisoning.

The effect of mannitol and anisodamin on the prevention of free radical injury to post-ischaemia flaps: an experimental study

Rat abdominal skin flaps were subjected to total venous occlusion for 8 h. Five minutes before release of the vascular occlusion, mannitol, mannitol plus anisodamin, anisodamin or placebo (0.9% normal saline) was administered intravenously. Drug treated flaps showed a statistically significant increase in the proportion of area surviving (P < 0.001). The combination of mannitol and anisodamin was not more effective than either agent alone in increasing the proportion of area surviving. The results of biochemical analyses indicated that neither mannitol nor anisodamin affected xanthine oxidase activity (p > 0.05) but that both agents significantly reduced the increase of malondialdehyde (MDA) concentration caused by ischaemia-reperfusion (p < 0.01). Treatment with mannitol or anisodamin also prevented the increase of lactate and water content and the decrease in glucose content in the island skin flap tissue which occurred on reperfusion. The data indicate that mannitol and/or anisodamin have the potential to salvage anticipated flap necrosis. It is possible that the mechanism of action is inhibition of damage caused by toxic oxygen species and improvement in capillary reperfusion.

3-Nitropropionic acid produces indirect excitotoxic damage to rat striatum

The mechanism of striatal damage induced by 3-nitropropionic acid (3-NPA) was studied in rats by neuropathological and neurochemical methods. Neuronal shrinkage with astrogliosis was observed in striatum after local injection of 0.5-5 mumol 3-NPA. Decortications involving dorsal and lateral aspects of frontal cortex or both frontal and parietal cortices significantly decreased the severity of striatal injuries induced by 3-NPA. This result suggests that corticostriatal projections play an important role in the development of striatal damage. No significant increase of glutamate and aspartate in striatal dialysates was observed, which indicated that 3-NPA may affect the postsynaptical sites and make the striatal neurons more vulnerable to endogenous levels of glutamate. Both of these findings suggested that 3-NPA produces indirect excitotoxic lesion to striatum. An increase of dopamine found in striatal dialysates may also be related to the occurrence of striatal damage.

[Anastomosis of small artery using ZT medical adhesive and soluble stent]

The conventional technique of interrupted suture in microvascular anastomosis is difficult to perform and timeconsuming. A new method with ZT medical adhesive and soluble intravascular stent is introduced. Using this method, end-to-end anastomosis of small arteries could be performed easily and quickly. Both the patency rate and histopathologic changes at the anastomosis sites were examined. In comparison with suture technique, similar patency rate was obtained. Inflammatory reaction in mid and outer layers of the vessel was observable and reendothelialization of the intima was identical.

[Applied anatomy of lymph drainage of lower lip mucosa]

The lymph drainage of lower lip mucosa was studied in 30 fresh cadavers of fetus and neonatus by submucosa injection of 30% Prussian blue of chloroform solution. The collecting lymphatics in lateral third of both the right and left sides of the lower lip mucosa ran laterally to the angles of the mouth, and then back- and downward between mandible and depressor muscle of angle of mouth, and finally, accompanying the facial vessels, emptied into submandibular lymph nodes. The efferent lymphatics of the latter emptied into angular lymph nodes and jugulo-omohyoid lymph nodes. The collecting lymphatics in the middle third of the lower lip mucosa went superficially to the mental muscle and downward into submental lymph nodes. The efferent lymphatic of the latter emptied, anteriorly to the body of the hyoid bone, latter- and downward into right and left jugulo-omohyoid lymph nodes. All collecting lymphatics lie in the loose connective tissue between the muscles.