Expression of binding of plasminogen, thrombospondin, vitronectin, and fibrinogen, and adhesive properties by Escherichia coli strains isolated from patients with colonic diseases

Escherichia coli strains isolated from patients with colonic disorders (n = 27) and strains isolated from the rectal mucosa of healthy subjects (n = 24) were compared with respect to expression of cell surface hydrophobicity, carriage of intestinal virulence factors, adhesion to tissue culture cells, and expression of binding of extracellular matrix proteins and plasma proteins. Strains isolated from patients with colonic disease did not express a more hydrophobic cell surface than strains from healthy subjects. Few strains from both groups carried genes encoding for recognised virulence factors of E coli. Only one strain, carrying the eae gene induced actin polymerisation in tissue culture cells. Strains from patients with colonic diseases adhered to HT29 cells, which are of intestinal origin, to a higher extent than E coli from healthy subjects. Significantly more strains from patients with colonic disorders than E coli from healthy subjects expressed binding of fibronectin, collagens, laminin, vitronectin, plasminogen, throbospondin, and fibrinogen. Expression of binding of these proteins may influence the pathogenesis of colonic disease by mediating binding to ulcerated tissue, preventing complement induced lysis of bacteria and by exerting proteolytic activity. There was no correlation between serotype, expression of cell surface hydrophobicity, and binding of extracellular matrix and plasma proteins.

[The protective effects of drugs H and X on liver cold ischemic injury]

Using isolated perfusion rat liver model (IPRL), we studied the protective effects of drugs H and X on rat's liver cold ischemic injury. After the rat's liver was preserved for 12 hours in Collins II solution with the addition of drugs H and X, the necrotic rate of sinusoidal lining cells was significantly lower than that of control group. Within certain range of the dosage of drugs H and X, the necrotic rate of sinusoidal lining cells was in the inverse ratio of the dosage in the Collins II solution. We also found that drugs H and X had obvious protective effect on liver cell redox function. But these drugs could not inhibit tissue from swelling after Collins II solution preservation. The protective mechanisms of the drugs maybe relate to the remoral of free radicals and suppression of Kupffer's cells activity.

Primary hyperparathyroidism in patients who have received radiation therapy and in patients who have not received radiation therapy

BACKGROUND

Primary hyperparathyroidism (HPT) occurs more frequently in persons who have been exposed to low-dose therapeutic radiation. Little information is available concerning whether or not the clinical, metabolic, and pathologic manifestations, as well as outcome, differ in these patients when compared with patients with sporadic HPT.

STUDY DESIGN

Records from 438 unselected patients with primary HPT, who were treated from 1982 to 1993 were retrospectively analyzed. All patients prospectively received a standard questionnaire preoperatively and postoperatively concerning clinical manifestations and a history of radiation exposure. Forty-nine patients had a history of radiation exposure (rHPT), whereas 389 did not have sporadic HPT (sHPT).

RESULTS

There was no difference in gender (36 women and 13 men versus 289 women and 100 men) or age (mean of 52 +/- 12 versus 57 +/- 16 years) in patients with rHPT or sHPT. Fatigue, neuropsychiatric disorders, memory loss, nocturia, and polyurea were more common in patients with sHPT (p < 0.05), whereas pain in joints was more common in patients with rHPT (63 versus 52 percent; p < 0.001). Serum calcium levels were similar (11.1 +/- 0.8 versus 11.2 +/- 0.8 mg per dL), but serum parathyroid hormone levels were higher in rHPT (448 +/- 14 percent of upper limit of normal versus 371 +/- 12 percent upper limit of normal). The parathyroid pathology was similar in the two groups (single adenoma 74 versus 72 percent, hyperplasia 14 versus 16 percent, and double adenoma 12 versus 12 percent in rHPT versus sHPT, respectively). Thyroid pathology was more common in the rHPT group (multinodular goiter 27 versus 7 percent and papillary thyroid carcinoma 14 versus 0.3 percent). Seven (1.8 percent) of patients not receiving radiation therapy treated by us had persistent HPT, but no patients receiving or not receiving radiation therapy had recurrent HPT during the follow-up period (six years).

CONCLUSIONS

Patients who have HPT after radiation treatment have more thyroid neoplasms but are otherwise quite similar to other patients with primary hyperparathyroidism.

Isoform-specific complementation of the yeast sac6 null mutation by human fimbrin

The actin cytoskeleton is a fundamental component of eukaryotic cells, with both structural and motile roles. Actin and many of the actin-binding proteins found in different cell types are highly conserved, showing considerable similarity in both primary structure and biochemical properties. To make detailed comparisons between homologous proteins, it is necessary to know whether the various proteins are functionally, as well as structurally, conserved. Fimbrin is an example of a cytoskeletal component that, as shown by sequence determinations and biochemical characterizations, is conserved between organisms as diverse as Saccharomyces cerevisiae and humans. In this study, we examined whether the human homolog can substitute for the yeast protein in vivo. We report here that two isoforms of human fimbrin, also referred to as T- and L-plastin, can both substitute in vivo for yeast fimbrin, also known as Sac6p, whereas a third isoform, I-fimbrin (or I-plastin), cannot. We demonstrate that the human T- and L-fimbrins, in addition to complementing the temperature-sensitive growth defect of the sac6 null mutant, restore both normal cytoskeletal organization and cell shape to the mutant cells. In addition, we show that human T- and L-fimbrins can complement a sporulation defect caused by the sac6 null mutation. These findings indicate that there is a high degree of functional conservation in the cytoskeleton, even between organisms as diverse as S. cerevisiae and humans.

National food contamination monitoring programmes-levels of mercury, lead and cadmium in Chinese foods

Six hundred and thirty-four food samples of six kinds were collected from Beijing, Shanghai, Jiangsu, Sichuan, Jilin and Guangdong areas, China and Hg, Pb, Cd contents were determined. The results showed that their levels in the Chinese foods were low; their levels in meat, egg, milk and fish were generally below the national hygienic standard. The average daily dietary intake of Hg, Pb, Cd were 7.25 micrograms, 103.77 micrograms and 30.72 micrograms respectively and they were all less than the ADI established by WHO.

Role of nitric oxide in the regulation of oxygen consumption in conscious dogs

The role of nitric oxide (NO) in the regulation of O2 consumption was studied in chronically instrumented conscious dogs. A specific NO synthesis inhibitor, nitro-L-arginine (NLA, 30 mg/kg i.v.), significantly increased mean arterial pressure from 100 +/- 4 to 134 +/- 5 mm Hg (mean +/- SEM) and total peripheral resistance by 157 +/- 16% and reduced cardiac output by 47 +/- 3% and heart rate by 34 +/- 6% after 120 minutes. Changes in arterial blood gases were not observed. There were significant changes in PO2 (-14 +/- 2 mm Hg), O2 saturation (-21 +/- 2%), the percentage of hemoglobin as oxyhemoglobin (-21 +/- 2%), and O2 content (-3.0 +/- 0.9 vol%) and a significant increase in percent reduced hemoglobin (21 +/- 1%) in mixed venous blood, associated with an increase in O2 extraction (5.1 +/- 0.2 vol%) (all P < .01). O2 consumption was increased from 124 +/- 6 to 155 +/- 9 mL/min (P < .05). Methoxamine, titrated to have hemodynamic effects similar to those of NLA (eg, mean arterial pressure increased from 97 +/- 4 to 131 +/- 5 mm Hg), had much smaller effects on venous blood gases, hemoglobin, and O2 extraction (2.3 +/- 0.7 vol%) and no significant effect on O2 consumption. NLA also caused an increase in O2 consumption of 37 +/- 8% (P < .01) in quietly resting conscious dogs that had undergone pretreatment with hexamethonium and atropine, but no significant change in O2 consumption in dogs anesthetized with barbiturate.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of EDRF/NO in parasympathetic coronary vasodilation following carotid chemoreflex activation in conscious dogs

The role of endothelium-derived relaxing factor (EDRF) in parasympathetic coronary vasodilation following carotid chemoreflex activation induced by nicotine in conscious dogs and stimulation of the vagus nerve in anesthetized dogs was studied. Injection of nicotine (11 +/- 4 micrograms) into the carotid artery increased coronary blood flow (CBF) by 126 +/- 16% from 28 +/- 3 ml/min and reduced late diastolic coronary resistance (LDCR) by 43 +/- 4% from 3.58 +/- 0.52 mmHg.ml-1.min, accompanied by a significant increase in mean arterial pressure and a decrease in heart rate (all P < 0.01). Pacing and propranolol did not change the coronary vascular response to chemoreflex activation. There were still increases in CBF by 113 +/- 17% from 29 +/- 3 ml/min and decreases in LDCR by 41 +/- 5% from 3.13 +/- 0.52 mmHg.ml-1.min (all P < 0.01). After infusion of N omega-nitro-L-arginine (L-NNA) (30 mg/kg), the increase in CBF following chemoreflex activation was only 23 +/- 3% from 37 +/- 3 ml/min, and the fall in LDCR was 19 +/- 3% from 3.09 +/- 0.51 mmHg.ml-1.min. Stimulation of the vagus nerve showed a relationship between stimulation frequency and coronary vasodilation that was significantly inhibited by L-NNA. Thus EDRF plays an important role in mediating parasympathetic coronary vasodilation during chemoreflex activation and perhaps during many reflexes that cause vagal cholinergic vasodilation in the heart.

Role of EDRF in the regulation of regional blood flow and vascular resistance at rest and during exercise in conscious dogs

The contribution of endothelium-derived relaxing factor (EDRF) to the regulation of regional vascular resistance and tissue blood flow at rest and during acute moderate exercise was studied in chronically instrumented conscious dogs. Radioactive microspheres were injected before and during exercise to measure regional blood flow. An infusion of nitro-L-arginine (L-NA), an analogue of L-arginine, was used to inhibit the synthesis of EDRF and resulted in a significant increase in mean arterial pressure, associated with significantly elevated vascular resistance in heart, skeletal muscle, renal and splanchnic circulations and with decreases in tissue blood flow in those regions at rest. Acute exercise caused a typical redistribution of blood flow, in which there was vasodilation in heart and working skeletal muscles, accompanied by vasoconstriction in kidney and splanchnic circulations. L-NA resulted in significantly elevated vascular resistance during vasodilation in heart and working skeletal muscles and also significantly increased vasoconstriction in renal cortex, stomach, pancreas, liver, and colon during exercise. Blood flows during exercise were largely unaffected by L-NA treatment. Our results suggest that whereas EDRF functions to regulate basal vascular tone and vascular resistance during exercise, EDRF has a minor role in determining the pattern of the redistribution of tissue blood flow during exercise.

[Comparative study of organ storage solutions for rat liver preservation: effects of HX and Collins I solution on sinusoidal lining cells and hepatic functions]

The liver sinusoidal lining cell injury and biochemical function changes were studied with isolated perfusion after rat livers had been preserved in HX solution or in Collins II solution. Seventy inbred Wistar rats were randomly divided into control group (n = 10), group H (preserved with HX solution, n = 30), and group C (preserved with Collins II solution, n = 30). The effects of the storage solutions were assessed by measuring the sinusoidal lining cell mortality (SLCM), Krebs-Henseleit perfusate ketone body ratio (PKBR), the hepatic sugar release (SL), and the number of livers secreting bile during isolated perfusion. The results suggest that the HX solution be much superior to Collins II solution in preventing sinusoidal lining cell injury and maintaining normal hepatic functions.

Purification of collagen-binding proteins of Lactobacillus reuteri NCIB 11951

Collagen type-I-binding proteins of Lactobacillus reuteri NCIB 11951 were purified. The cell surface proteins were affinity purified on collagen Sepharose and eluted with an NaCl gradient. Two protein bands were eluted from the column (29 kDa and 31 kDa), and both bound radio-labeled collagen type I. Rabbit antisera raised against the 29 kDa and 31 kDa protein reacted with the affinity-purified proteins in a Western blot with whole-cell extract used as antigen. The N-terminal sequence of the 29-kDa and 31-kDa proteins demonstrated the closest homologies with internal sequences from an Escherichia coli trigger factor protein (TIG.ECOLI). Out of nine other lactobacilli, the antisera reacted only with the L. reuteri and not with the other species tested.

Identification of I-plastin, a human fimbrin isoform expressed in intestine and kidney

The complete cDNA sequence of human intestine-specific plastin (I-plastin) was determined from a clone derived by PCR. It consists of a 97-bp 5' untranslated region, a 1,887-bp coding region, and a 1,655-bp 3' untranslated region. The coding region predicts a 629-residue polypeptide whose sequence displays 86, 75, and 73% identities with chicken intestine fimbrin, human T-plastin, and human L-plastin, respectively. Recombinant I-plastin cross-linked actin filaments into bundles in the absence but not in the presence of calcium. The I-plastin gene was mapped by PCR to human chromosome 3; the L- and T-plastin genes were previously mapped to chromosomes 13 and X, respectively. I-plastin mRNA was detected in the small intestine, colon, and kidneys; relatively lower levels of expression were detected in the lungs and stomach. In contrast, L-plastin expression was restricted to the spleen and other lymph node-containing organs, while T-plastin was expressed in a variety of organs, including muscle, brain, uterus, and esophagus. In contrast to the situation for the intestine, high levels of L- and T-plastin mRNAs were detected in Caco-2, a human colon-derived cell line. Immunofluorescence microscopy detected I-plastin in the brush border of the small intestine and colon. These results identify I-plastin as the human homolog of chicken intestine fimbrin and as a third plastin isoform in humans.

Effects of prolonged darkness on light responsiveness and spectral sensitivity of cone horizontal cells in carp retina in vivo

Light responses of cone- and rod-driven horizontal cells were recorded intracellularly from opened eyes of intact, immobilized carp and the effects of prolonged darkness on these cells were examined. When the retina was left in the dark, responses of cone horizontal cells to a moderate test flash presented once every 10 min gradually and steadily decreased in size (dark suppression effect). Following a repetitive presentation of the test flash, the light responsiveness of the cells was enhanced. In contrast, the rod horizontal cells did not show the dark suppression effect and the light responsiveness of these cells increased in the dark. Effects of prolonged darkness on the spectral sensitivity of L-type and R/G-type cone horizontal cells were also studied. The spectral sensitivity of L-type cells, determined just after background illumination was extinguished, agreed reasonably well with that of red-sensitive (R-) cones, but it matched better that of green-sensitive (G-) cones when determined in prolonged darkness. We further show that depolarizing responses of R/G-type cone horizontal cells to long-wavelength flashes, driven by R-cones, were abolished after prolonged darkness. Taken together, these results suggest that input from R-cones converging onto the cone horizontal cells is more significantly suppressed after prolonged dark adaptation than input from G-cones. Due to the suppression of the R-cone input, enhancement of responses of the L-type cone horizontal cells to long-wavelength stimulation in the presence of a green background light was no longer seen after prolonged darkness.(ABSTRACT TRUNCATED AT 250 WORDS)

Polymorphous ventricular tachycardia after intracoronary papaverine: a report of 3 cases

Three cases with polymorphous ventricular tachycardia following a standard dose of intracoronary papaverine during 102 measurements of coronary flow reserve are reported. This study suggests that all patients should be closely monitored while receiving intracoronary papaverine and that extreme caution should be employed when the drug is administered to patients with QT interval prolongation and poor coronary flow reserve.

Atrial fibrillation and coronary artery disease

A retrospective study of the incidence of atrial fibrillation in 703 consecutive patients who had undergone selective coronary arteriography and left ventricular catheterization between November 1986 and May 1992 was undertaken. The study group included 136 patients with significant coronary stenosis (> 50% diameter reduction) without previous myocardial infarction (group I), 157 with a history of myocardial infarction (group II), 326 with chest pain and normal coronary angiography (group III), 72 with valvular disease (group IV), and 12 with cardiomyopathy (group V). Clinical and electrocardiographic evidence of atrial fibrillation was documented in 75 patients (10.7%), including 2 (1.5%) in group I, 6 (3.8%) in group II, 36 (11%) in group III, 27 (37.5%) in group IV, and 4 (33.3%) in group V. The rate of occurrence of atrial fibrillation was lower in groups I and II than in groups III, IV and V. Atrial fibrillation was rarely found in coronary artery disease.

Double parathyroid adenomas. Clinical and biochemical characteristics before and after parathyroidectomy

OBJECTIVE

There is considerable debate about whether double parathyroid adenomas are a discrete entity or represent hyperplasia with parathyroid glands of varying sizes. This distinction is important because it impacts on the extent of parathyroid resection and the success of the parathyroid operation.

SUMMARY BACKGROUND DATA

Double parathyroid adenomas have been reported to occur in 1.7% to 9% of patients with primary hyperparathyroidism (HPT). It is important for surgeons to differentiate between double adenoma and hyperplasia with glands of varying sizes using gross examination during the initial procedure because microscopic findings of a small biopsy specimen at frozen-section examination may not be diagnostic.

METHODS

From 1982 to 1992, 416 unselected patients (309 women and 107 men) with primary HPT without familial HPT or multiple endocrine neoplasia (MEN) were treated by one surgeon at the University of California at San Francisco. Double adenoma occurred in 49 patients, solitary adenoma in 309 patients, and hyperplasia in 58 patients. The authors analyzed the clinical manifestations, the preoperative and postoperative serum levels of calcium, phosphate, and parathyroid hormone (PTH), and the success rate and outcome after parathyroidectomy and compared their results in 49 patients with double adenomas to the results for patients with solitary adenomas or hyperplasia.

RESULTS

Ten of the patients with double adenomas (20.4%) were referred for persistent HPT after removal of one abnormal parathyroid gland. The ages of the patients with double adenoma, single adenoma, and hyperplasia were 61 +/- 14, 56 +/- 15, and 58 +/- 7 years, respectively. Fatigue, muscle weakness, and bone pain were common in patients with double adenomas, whereas nephrolithiasis occurred more frequently in patients with solitary adenoma (p = 0.0001). Serum calcium and PTH levels (per cent of upper limit of normal) fell from 11.5 +/- 1.2 mg/dL and 487% to 9.5 +/- 0.8 mg/dL and 61% for patients with double adenomas; from 11.9 +/- 0.9 mg/dL and 378% to 9.3 +/- 1.4 mg/dL and 101% for patients with single adenoma; and from 10.9 +/- 0.5 mg/dL and 418% to 9.1 +/- 0.7 mg/dL and 94% for patients with hyperplasia, respectively. There was no recurrence in the patients with double adenomas with a mean follow-up time of 5.8 years.

CONCLUSIONS

Double adenomas are a discrete entity and occur more often in older patients. Patients with double adenomas can be successfully treated by removal of the two abnormal glands.

Isolation of STD1, a high-copy-number suppressor of a dominant negative mutation in the yeast TATA-binding protein

The TATA-binding protein (TBP) is an essential component of the transcriptional machinery of all three nuclear RNA polymerase enzymes. Comparison of the amino acid sequence of TBPs from a number of species reveals a highly conserved 180-residue C-terminal domain. In contrast, the N terminus is variable in both size and amino acid sequence. Overexpression of a TBP protein with a deletion of the nonconserved N terminus (TBP delta 57) in Saccharomyces cerevisiae results in a dominant negative phenotype of extremely slow growth. Associated with the slow-growth phenotype are defects in RNA polymerase II transcription in vivo. We have screened a high-copy-number yeast genomic library for suppression of the slow-growth phenotype and have isolated plasmids which encode suppressors of TBP delta 57 overexpression. Here we report the sequence and initial characterization of one suppressor, designated STD1 for suppressor of TBP deletion. The STD1 gene contains a single continuous open reading frame with the potential to encode a 50.2-kDa protein. Disruption of the STD1 gene indicates that it is not essential for vegetative growth, mating, or sporulation. High-copy-number suppression by the STD1 gene is not the result of a decrease in TBP delta 57 protein accumulation or DNA-binding activity; instead, STD1 suppression is coincident with the elimination of TBP delta 57-induced RNA polymerase II defects in both uninduced and induced transcription in vivo.

Clinical and experimental studies on shallow needling technique for treating childhood diarrhea

Treatment of diarrhea in children by shallow needling and by drugs was studied in 3 separate groups for comparison. For Group I, the lateral line II of the forehead was taken, i.e. the upper, middle and lower points of the line staring from Toulinqi (UB 15) vertically downwards to the place 1 cm below the hairline were selected. For Group II, shallow needling was done on body acupoints, the main points selected being Qihai (Ren 6), Shuifen (Ren 9), bilateral Tianshu (St 25), and bilateral Zusanli (St 36); the adjuvant acupoints were Taibai (Sp 3) and Gongsun (Sp 4). The depth of shallow needling was merely puncturing the skin. For Group III the drugs used were Liteling, Berberine, Gentamycin, Ampicillin, and SMZ Co. The results of treatment in Group I and II differed insignificantly, while both were significantly superior to drugs in Group III. Experimental studies also showed that shallow needling enhanced the humoral and cellular immunity and promoted the intestinal peristaltic function.

Identity elements of tRNA(Trp). Identification and evolutionary conservation

In this study, the varying reactivities of Bacillus subtilis tryptophanyl-tRNA synthetase toward prokaryotic, eukaryotic, and halophile tRNAs were employed to define the potential identity elements on tRNA(Trp). On this basis mutagenesis was performed to obtain, through in vivo heterologous expression in Escherichia coli and in vitro transcription with T7 RNA polymerase, mutant B. subtilis tRNA(Trp) for comparison with the wild-type. These comparisons served to establish G73 and the anticodon as major identity elements, and A1-U72, G5-C68, and A9 as minor identity elements. While the tryptophanyl-tRNA synthetase from B. subtilis and E. coli require G73 to function, replacement of G73 by A73 favors the enzyme from yeast. This change points to the variation of the identity elements for the same amino acid among different organisms. The similarity in these elements between B. subtilis and E. coli tryptophanyl-tRNA synthetase, however, suggests that identity elements on tRNA, like the active centers on enzymes, undergo evolutionary change at slower rates than less essential portions of the macromolecule.

Purification of hyperexpressed Bacillus subtilis tRNA(Trp) cloned in Escherichia coli

To study the effects of evolutionary sequence changes on the molecular interactions of tRNA inside the cell, the Bacillus subtilis tRNA(Trp) gene has been cloned into Escherichia coli JM109 under the control of the lac promotor. Hyperexpression of the gene in minimal medium upon induction yielded 28% of total tRNA in the form of B. subtilis tRNA(Trp). The tRNA(Trp) gene product was purified by the use of a single Vydac C4 high-performance liquid chromatography (HPLC) matrix. This experimental system provided a valuable system for the hyperexpression and purification of a heterologous tRNA for studies in vitro. Moreover, because HPLC fractionation of the heterologous tRNA(Trp) gene product yielded multiple peaks, the system made possible an analysis of the molecular mechanisms for the transcriptional modifications of the tRNA(Trp) gene product in vivo.

Effects of copper coordinate complexes on the scavenging of reactive oxygen species

Effects of a 20-membered macrocyclic bicopper complex and dioxotetramine copper complexes with linear or cyclic structure on the scavenging of ROS have been studied by ESR. The results indicated that all three copper coordinate complexes have SOD mimetic activity. The dioxotetramine copper complex with linear or cyclic structure did not have the scavenging effect on .OH produced by H2O2-Fe++ and 1O2 produced by the H2O2-NaOCl system, but the 20-membered macrocyclic bicopper complex was found to be capable of depressing the intensity of the ESR spectrum of the adduct formed from TMP and 1O2 as well as making the spectrum of DMPO-OH adduct splittings. This fact may suggest that there are interactions between the ROS and 20-membered macrocyclic ring in the SOD mimic.

Vaccination of bovines against Schistosomiasis japonica with cryopreserved-irradiated and freeze-thaw schistosomula

Four laboratory tests and one field trial with cryopreserved irradiated (CI) schistosomula vaccine and a freeze-thaw (F/T) vaccine against bovine Schistosomiasis japonica were carried out in 1979 and 1980 with the following results: (1) Single intradermal vaccination in buffalo calves each with 10,000 20 krad CI Schistosomula plus 1 ml BCG gave 62% worm reduction (P < 0.05). Using the same protocol 55% worm reduction (P < 0.01) was obtained in cattle. (2) Buffalo calves immunized twice, at a 1.5 month interval, with 10,000 and 20,000 CI schistosomula, respectively, resulted in a worm reduction 65%. (3) In a preliminary field trial with 10,000 CI schistosomula plus 1 ml BCG resulted in a worm reduction of 53% in buffalo calves. (4) Intradermal vaccination of 30,000 F/T schistosomula with 1 ml BCG was also tried in cattle and revealed a worm reduction of 57% but increasing the number of vaccinations did not improve the protective effect. (5) Evidence regarding the effects of immunization with CI vaccine in buffaloes and F/T vaccine in cattle, on the number of eggs and miracidia and that of female worms themselves was obtained. (6) Immune responses, cellular and humoral, elicited in buffaloes vaccinated with CI schistosomula were detected by means of Lymphocyte Transformation Assay and Enzyme Linked Immunosorbent Assay.

Binding of Escherichia coli to Penrose rubber drains--an in vitro study

Ten different isolates of Escherichia coli were used to compare bacterial attachment to Penrose rubber drains at different temperatures and to investigate a possible relation with cell surface hydrophobicity and charges, as well as the capacity of autoaggregation. Penrose rubber drain pieces of 1 cm2 were incubated with 4.8 x 10(6) E. coli cells for 1 h at 22, 37 and 42 degrees C, respectively. After rinsing with phosphate buffered saline (PBS), the number of adhering bacteria on the drain pieces was calculated by measuring cellular ATP (adenosine triphosphate) bioluminescence. Bacterial cell surface properties at different temperatures were determined by two-phase partitioning and autoaggregation was determined by arbitrary scoring under the dissecting microscope. For most strains of E. coli, the number of adherence to Penrose rubber drain was higher at 22 degrees C than at 37 degrees C and 42 degrees C. Bacterial cell-surface properties and autoaggregation capacity were influenced by the growth temperature, but without correlation to bacterial ability to attach to rubber drains. Thus, the present study demonstrates that attachment of E. coli to Penrose rubber drains was significantly influenced by temperature, but bacterial cell-surface hydrophobicity and charge as well as autoaggregation capacity had no influence on bacterial attachment ability.

The results of treatment in 100 patients with limited-stage small cell lung cancer

BACKGROUND

In an attempt to improve treatment results of small cell lung cancer (SCLC), combined induction chemotherapy and thoracic and prophylactic brain radiation therapy were administered.

METHOD

From December 1980 to December 1987, 112 patients with limited-stage SCLC were treated with combination induction chemotherapy and thoracic or prophylactic brain radiation therapy; 100 were evaluable.

RESULTS

The complete response rate was 40%, and complete and partial responses totaled 94%, with a 5-year survival rate of 23%. There was no difference in remission and survival rates between three-drug and four-drug induction chemotherapeutic regimens. Six chemotherapeutic courses produced longer survival than less therapy. Although the occurrence of brain metastases was no different with or without prophylactic brain radiation therapy, the 3-year survival after this procedure was improved.

CONCLUSION

Treatment of limited-stage SCLC with induction chemotherapy and thoracic and prophylactic brain radiation therapy produced improved remission and survival rates.

Evaluation of 90:10 poly(D,L-lactide-co-glycolide) microspheres containing norethisterone: drug release and biodegradation

Poly(D,L-lactide-co-glycolide) (PLG, 90:10) microspheres containing 20% norethisterone (NET) were prepared by solvent evaporation method. Microspheres in the size ranges of 65 to 100 microns were sterilized by irradiation and used for further study. In vitro release showed fairly constant release of NET from the above microspheres over more than 90 days. However, in vivo drug release determined by residual NET analysis after i.m. injection in rats indicated a faster release rate. About 95% of NET was released in a period of 45 days. At the dose of 80 mg of microspheres, vaginal estrus cycles were inhibited for 45 days compared to 27 days for the same dose of NET crystals in rats. Biodegradation of the microspheres was tested by direct measurement of molecular weight losses and SEM observation of morphological changes of the microspheres, which showed continuous erosion in the internal matrix of microspheres with the decrease of molecular weight of PLG until total collapse of microspheres, and biodegradation was faster in rats than in human serum at 37 degrees C in vitro. Total degradation of 90:10 PLG microspheres was less than 7 months in rats and more than 9 months in vitro.

The inhibitory effects of 21 mimics of superoxide dismutase on luminol-mediated chemiluminescence emitted from PMA-stimulated polymorphonuclear leukocyte

Four groups comprising 21 superoxide dismutase (SOD) mimics synthesized by us were comparatively studied for their inhibitory effects on luminol-mediated chemiluminescence emitted from phorbol myristate acetate (PMA)-stimulated polymorphonuclear leukocyte (PMNL). Among these groups, 20-membered macrocyclic bicopper(II) complexes and 13-membered macrocyclic dioxotetramine copper(II) complexes exhibited relatively higher activities of scavenging reactive oxygen species (ROS) produced by PMA-stimulated PMNL as compared with polyamine Cu(II)-Zn(II) complexes and copper(II) complexes of bis-shiff-base. Moreover, distinctly different effects of SOD mimics in the biological system have been found even in the same group. It is suggested that the biological effects of some SOD mimics are related to their structures.

Normocalcemic hyperparathyroidism. Biochemical and symptom profiles before and after surgery

Patients with normocalcemic hyperparathyroidism represent a diagnostic and therapeutic challenge. It is unclear to what extent these patients benefit from surgery in terms of correction of their serum chemistry abnormalities and their symptoms. We studied 142 patients: 23 with normocalcemic hyperparathyroidism (serum calcium levels below 2.62 mmol/L), 35 with intermittent hypercalcemia, and 84 with hypercalcemic hyperparathyroidism. Serum chemistry analyses and a standardized questionnaire of symptoms were completed before and after surgery. Overall, patients in the normocalcemic group reported a similar frequency of preoperative symptoms; had a similar reduction in postoperative symptoms; and had a similar normalization of serum calcium, parathormone, and phosphate levels as those in the two control groups. This study indicates that factors other than elevated serum calcium levels are in large part responsible for the symptoms of hyperparathyroidism and that these patients benefit from operation.

Characterization of a Gy4 glycinin gene from soybean Glycine max cv. forrest

The glycinin gene family encoding the glycinin subunits in soybean plants is composed of at least five gene members. A genomic clone lambda S312 containing the Gy4 gene from a genomic library of cv. Forrest was isolated and partially characterized. The organization of this gene was found to be similar to that of a null allele from cv. Raiden, but different from the Gy4 gene from cv. Dare. The complete nucleotide sequence of this gene has been determined. It is 2599 bp long consisting of four exons and three introns. Comparing the DNA sequences between this gene and the gene from Dare and a null allele from Raiden, the difference found in the coding region was 5'-GCAGTGCAAG-3' (nt 824 to 833) in the former case versus 5'-TGGAGTTGCAATT-3' (nt 1314 to 1326) in the latter case in the exon 2 domain, resulting in three amino acid differences and one amino acid absence. Some other differences were also found in the non-coding region. The coding sequence and 5'-flanking region of the Gy4 gene, when compared with that of other legumin genes as well as group 1 glycinin subunit genes, revealed some interesting features: (1) a transposable element-like sequence was found in the hypervariable region (HVR) of the exon 3 domain, which was lacking in the legumin and the glycinin group 1 genes; (2) in the 5'-flanking region from nt -145 to -1, two high-homology sequences were found: one from nt -141 to nt -132, the other from nt -118 to nt -92 which includes the 'legumin box' and the RY repeat element.

Antitumor activity of siwenmycin: a novel anthracycline antibiotic

A novel anthracycline antibiotic, siwenmycin, isolated from the culture of Streptomyces galilaeus var. siwenesis, was examined for its antitumor activities against P388, K562, B16-F10, HeLa, HEp-2 and Lewis lung carcinoma cell lines. The results showed that siwenmycin was effective against P388, K562, HeLa and HEp-2 tumor cell lines in vitro, and significantly inhibited the growth of the Lewis lung carcinoma cell line in vivo. Siwenmycin could also suppress spontaneous and artificial pulmonary metastases of B16-F10 and Lewis lung carcinoma cell lines in C57BL/6 mice. The inhibitory effect of siwenmycin on spontaneous pulmonary metastasis of Lewis lung carcinoma in C57BL/6 mice was even stronger than that of adriamycin (ADM), which is, at present, commonly used in clinical practice. Furthermore, the double-labeling test used in this study has verified that siwenmycin can inhibit cellular RNA synthesis at about one tenth the concentration required to inhibit DNA synthesis to the same degree, indicating that the antitumor mechanism of siwenmycin also differs from that of ADM. The acute toxicity of siwenmycin was very low, and it was as effective in vivo as in vitro, suggesting that this newly found antibiotic should be studied for possible clinical antitumor applications.

A new 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for testing macrophage cytotoxicity to L1210 and its drug-resistant cell lines in vitro

Activated by interferon gamma (IFN gamma)(50 U/ml) and lipopolysaccharide (50 ng/ml), mouse peritoneal macrophages were cocultured with the L1210 parental cell line (L1210/PRT) and its Adriamycin-, cisplatin-resistant cell lines (L1210/ADM, L1210/CDDP) for 24 h at effector: target (E:T) ratios of 10:1, 5:1 and 2:1. The direct 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT)-cleavage assay, a new improved indirect MTT assay, and the colony-formation assay were used to quantify macrophage-mediated suppression of these non-adherent tumour targets. The results showed that the macrophages can produce formazan at a high level, which can interfere with the final results of a direct MTT assay. The new indirect MTT assay can avoid such interference because the effectors are separated from the targets before the assay is performed, so the real viability of the targets is reflected. An indirect MTT assay, as developed in this study, could be better than the direct assay for examining the suppressive effect of activated macrophages on non-adherent tumour cells in vitro. This study also revealed that all the L1210 cell lines can be suppressed significantly by the macrophages at E:T ratios of 10:1 and 5:1 while the two drug-resistant cell lines have lower survival rates at an E:T ratio of 10:1, indicating that they are more susceptible than their parental cell line.

Acetaminophen-induced cytotoxicity in cultured mouse hepatocytes: effects of Ca(2+)-endonuclease, DNA repair, and glutathione depletion inhibitors on DNA fragmentation and cell death

Hepatotoxic alkylation of mouse liver cells by acetaminophen is characterized by an early loss of ion regulation, accumulation of Ca2+ in the nucleus, and fragmentation of DNA in vitro and in vivo. Acetaminophen-induced DNA cleavage is accompanied by the formation of a "ladder" of DNA fragments characteristic of Ca(2+)-mediated endonuclease activation. These events unfold well in advance of cytotoxicity and the development of necrosis. The present study utilized cultured mouse hepatocytes and mechanistic probes to test whether DNA fragmentation and cell death might be related in a "cause-and-effect" manner. Cells were isolated by collagenase perfusion, cultured in Williams' E medium for 22-26 hr, and exposed to acetaminophen. Aurintricarboxylic acid, a general Ca(2+)-endonuclease inhibitor, and EGTA, a chelator of Ca2+ required for endonuclease activation, significantly decreased DNA fragmentation at 6 and 12 hr and virtually abolished cytotoxicity. N-Acetylcysteine also eliminated DNA fragmentation and cytotoxicity. 3-Aminobenzamide, an inhibitor of poly(ADP-ribose) polymerase-stimulated DNA repair, failed to alter the amount of DNA fragmentation at 6 hr but substantially increased acetaminophen cytotoxicity in hepatocytes at 12 hr. With the exception of when DNA repair was inhibited by 3-aminobenzamide, Ca2+ accumulation in the nucleus, DNA fragmentation, and hepatocyte death varied consistently and predictably with one another. Collectively, these findings suggest that unrepaired damage to DNA contributes to acetaminophen-induced cell death in vivo and may play a role in necrosis in vivo.

Acetaminophen-induced cytotoxicity in cultured mouse hepatocytes: correlation of nuclear Ca2+ accumulation and early DNA fragmentation with cell death

Hepatotoxic doses of acetaminophen cause widespread alkylation of liver and early loss of cytosolic Ca2+ regulation. Although the precise location and target of lethal alkylation are not known, Ca2+ accumulation is viewed as a possible link between cell alkylation and cell death. We have recently shown that Ca2+ accumulates in the nucleus and that DNA fragments in vivo before the development of acetaminophen-induced necrosis in mice. The present study examined cultured hepatocytes for nuclear damage and its association with cell death in vitro. Positive results would argue for two key points. (1) Nonparenchymal cell damage does not explain DNA fragmentation induced by acetaminophen in vivo. (2) A chemical that causes necrosis can produce DNA damage considered characteristic of apoptosis. Hepatocytes from NIH Swiss mice were isolated by collagenase perfusion, cultured in Williams' E medium for 24 hr, and exposed to acetaminophen. Cytotoxicity was assessed by lactate dehydrogenase leakage and release of [3H]adenine from a prelabeled nucleotide pool. Genomic DNA fragmentation was assessed quantitatively by colorimetric analysis and qualitatively by agarose gel electrophoresis. Acetaminophen caused DNA damage from 1-4 hr onward and produced significant release of lactate dehydrogenase and [3H]adenine nucleotides at later times. Agarose gel electrophoresis revealed a "ladder" of DNA fragments characteristic of Ca(2+)-mediated endonuclease activation. Cytotoxicity correlated with nuclear Ca2+ accumulation (r greater than 0.895, p less than 0.05) and with percentage DNA fragmentation (r greater than 0.835, p less than 0.05). Nuclear changes in vitro generally reproduced those observed in vivo. Collectively, these findings demonstrate that nuclear Ca2+ accumulation and DNA fragmentation appear as early events that correlate directly with later cytotoxicity. These changes may contribute to acetaminophen-induced injury leading to cell death in vitro and necrosis in vivo.

[Quantitative analysis of coronary arteriogram by a computer-assisted method]

A computer-assisted method for quantitating coronary arteriograms was applied to measure the diameter of major epicardial coronary arteries in 58 normal subjects and 25 hypertensive patients, and to determine the percentage of relative stenosis of coronary lesions in 109 patients with coronary artery disease. Average coronary size was larger than normal in patients with hypertension. The left coronary artery was larger than the right coronary artery in the majority of patients. The degree of coronary stenosis can be measured accurately with good reproducibility. Thus this inexpensive microprocessor system provides rapid quantitation of coronary artery diameter and lesions.

[Changes in left ventricular volumes after acute transmural myocardial infarction: clinical, angiographic and prognostic correlations]

The relation of left ventricular (LV) volume changes to clinical and angiographic features was assessed in 57 patients with a first transmural myocardial infarction. LV volumes were measured by two-dimensional echocardiography within 72 hours of admission and repeated at one month. The infarct-related artery (IRA) patency and collateral circulation were determined by coronary arteriography performed before discharge. LV end-diastolic and end-systolic volumes increased (155 +/- 44 vs 203 +/- 65 ml; 96 +/- 32 vs 134 +/- 57 ml, all P less than 0.01), and ejection fraction decreased (0.38 +/- 0.06 vs 0.34 +/- 0.09, P less than 0.05) in patients with totally occluded IRA without collaterals. In contrast, LV volumes and systolic function were unchanged in those who had subtotally occluded IRA or with collaterals. LV dilation (greater than or equal to 20% increase in LV end-diastolic volume) occurred more frequently in patients without residual flow to the infarct region (77%) than in those with (9%) (P less than 0.01). Thirteen patients with LV dilation developed congestive heart failure, 3 of whom having cardiac death. However, congestive heart failure was found in only 11 patients without LV dilation and no death occurred. Thus, the cardiac event rate was higher in patients with (65%) than in those without (30%) LV dilation (P less than 0.05). The study indicates that the changes in LV volumes following acute myocardial infarction are largely related to the status of residual flow to the infarct region and affect the clinical outcome of the patients.

HIPDM-SPECT brain imaging in the presurgical evaluation of patients with intractable seizures

We report the results of interictal and ictal HIPDM-SPECT brain imaging in 34 patients who eventually underwent temporal lobectomy for treatment of medically intractable complex partial seizures. Interictal studies revealed decreased regional cerebral perfusion (rCP) in the temporal lobe corresponding to the eventual site of surgery in 73% of the patients. Similarly, ictal study demonstrated increased rCP in 93% of the patients. In 69% of the patients, the SPECT studies were able to demonstrate both increased rCP on the ictal scan and decreased rCP on the interictal scan in the same location, corresponding to the eventual site of surgery. These results suggest that interictal and ictal SPECT brain imaging can be easily obtained and provide reliable localizing information in the presurgical evaluation of patients with medically intractable epilepsy.

Presenting the diagnosis of pseudoseizure

Simultaneous video-EEG monitoring has allowed pseudoseizures to be effectively diagnosed. Discussing the results of the monitoring with the patient is the 1st step in treatment. We outline a protocol for presenting the diagnosis of pseudoseizure with the goal of conveying to the patient the importance of knowing the nonepileptic nature of the spells and the need for psychiatric follow-up. The protocol also allows elicitation of sexual abuse history and the use of suggestion to aid in controlling the pseudoseizures.