Synthesis of a biological active tumor growth factor from the predicted DNA sequence of Shope fibroma virus

A 55-residue peptide comprising the carboxyl portion (residues 26-80) of the Shope fibroma virus growth factor (SFGF), a predicted 80-residue DNA virus gene product that encoded a homologous sequence with the epidermal growth factor transforming growth factor alpha family, was synthesized by a stepwise solid-phase method. The synthetic SFGF (26-80) purified to homogeneity by reverse-phase HPLC was characterized by fission ionization mass spectrometry and amino acid analysis. The disulfide pairings were established by enzymatic digestion and mass spectrometry and were found to be similar to those of EGF and TGF alpha. Synthetic SFGF (26-80) was found to share about 10% of the activities as EGF in the radioreceptor binding to A431 cells, stimulation of [3H]thymidine uptake in NRK cells, and induction of colony formation in soft-agar assay. Our results therefore confirmed that SFGF contained the putative biological activities of the EGF-TGF alpha family and that production of SFGF by Shope fibroma virus infected cells may account for the proliferative diseases associated with this particular virus.

Effects of noise exposure and task demand on cardiovascular function

Cardiovascular effects under various noise-exposure and task-demand conditions were studied among 40 senior highschool students. The subjects consisted of 20 males and 20 females with a mean age of 16.7 +/- 0.7 years. All subjects had equivalent abacus performance ratings. Each subject was tested with a random sequence of six sessions. The time limit set for each session was 33 min. Six experimental sessions were constructed by a random combination of noise exposure (60, 85 or 90 dB (A] white noise) and task demand (task presence or task absence) variables. Blood pressure measures were taken at the beginning and ending phases of each session. A task-demand variable was defined as a conjoint of mental arithmetic (3 min) and abacus arithmetic (30 min). The results from the present study show that the effect of noise exposure on task performance is remarkable. Only noise exposure tended to influence the performance of male students in abacus arithmetic. The effect of task demand on blood pressure was higher than that of noise exposure. No interaction effect (noise exposure x task demand) on blood pressure, was found via analyses of within-subjects two-way ANOVA.

A study of noise-induced hearing loss and blood pressure in steel mill workers

A cross-sectional study on noise-induced hearing loss and blood pressure was conducted in a steel mill company. Three hundred testees were selected by cluster sampling. They were physically examined and an audiometry was done. Only 151 workers, who had the highest hearing threshold at 4000 Hz and without any family history of hypertension or treatment of drugs on cardiovascular troubles, were selected as subjects in this study. Multiple regression analyses revealed that body mass index, employment duration, age and hearing loss explained a significant amount of variation in systolic and diastolic blood pressure (R2 = 0.16 and 0.12, respectively). There was no significant relationship between hearing loss and blood pressure. In order to adjust confounding factors, analyses of covariances were used and the results suggest that hearing loss is unrelated to blood pressure. It seems that hearing loss is not appropriate as a noise exposure index to measure the relationship between noise exposure and blood pressure.

Study of noise exposure and high blood pressure in shipyard workers

A cross-sectional and case-reference study of occupational noise exposure and blood pressure was conducted in a shipyard company. There were 158 male workers from the higher noise environment (greater than 85 dBA) and 158 matched workers from a lower noise environment (less than 80 dBA). The workers in the higher noise environment had higher systolic and diastolic blood pressure (p less than .05) after adjusting for confounding factors. Comparison of regression revealed that there is no different increase in blood pressure with age in different environmental noise exposure. Based on 63 matched hypertensive-normotensive pairs from 2,730 shipyard workers, the relative risk of hypertension among workers exposed to an over-85-dBA acoustic environment, compared to those under 80 dBA, was 2.38. It is suggested that there may be a population of noise-exposed workers at increased risk of high blood pressure.

Refractory cholangitis after Kasai's operation caused by candidiasis: a case report

A case of biliary atresia treated by Kasai portoenterostomy was re-explored a year later for refractory cholangitis, which failed to respond to antibiotic treatment. Unexpectedly, the granulation tissue obstructing the porta hepatis contained pseudohyphae of Candida albicans. After curettage and Amphotericin B local irrigation, the patient became afebrile and anicteric.

Treatment of esophageal atresia with distal tracheoesophageal fistula: are gastrostomy and prophylactic esophageal dilatation necessary?

Fourteen cases of esophageal atresia with distal tracheoesophageal fistula were treated by primary anastomosis (11 cases) or delayed primary anastomosis (3 cases) between August 1980 and September 1985. Postoperative esophageal dilatation was not used in the 13 survivors and none developed esophageal stricture. In the 11 cases of primary anastomosis, gastrostomy was performed simultaneously only in the first 2 cases. The omission of gastrostomy did not aggravate the preexisting pulmonary condition. Rather it shortened the operation time. It is considered that prophylactic esophageal dilatation is not necessary and gastrostomy is required only when primary anastomosis is not possible.

Response of sensitive human ataxia and resistant T-1 cell lines to accelerated heavy ions

We have studied the radiation dose responses of two human fibroblast lines: cells from a patient with Ataxia telangiectasia (AT-2SF) and an established line of human T-1 cells. Aerobic and hypoxic 225 kVp X-ray survival curves were used as controls to the heavy ion exposures. Nearly monoenergetic accelerated neon and argon ions were used at the Berkeley Bevalac with various residual range values. The LET of the particles varied from 30 keV microns-1 to over 1,000 keV microns-1. All Ataxia survival curves were exponential functions of the dose. Their radiosensitivity reached peak values at 100-200 keV microns-1. Human T-1 cells have effective sublethal damage repair as has been evidenced by split dose experiments, and they are much more resistant to low LET than to high LET radiation. At high LET their radiosensitivity approached that of the Ataxia cells. The repair-misrepair model has been used to interpret these results. According to this model, the molecular repair processes culminate either in eurepair or in misrepair. We have obtained mathematical expressions that describe the cross sections and inactivation coefficients for both human cell lines as a function of the LET and the type of particle used. We assume that the lesions induced in T-1 and Ataxia cells are qualitatively similar and that each cell line attempts to repair these lesions. The result in most irradiated Ataxia cells, however, is either lethal misrepair or incomplete repair leading to cell death. T-1 cells have efficient repair mechanisms at low LET, and the repair-misrepair model suggests that at high LET the T-1 cells can still efficiently repair individual lesions, but that as the lesions become closely spaced along the tracks, the probability of misrepair increases.

Colorectal cancer and schistosomiasis

The risk of colorectal cancer is known to be increased in patients with long-standing schistosomal colitis. A retrospective review of clinical data and surgical specimens from 60 patients with schistosomal granulomatous disease of the large intestine but without carcinoma demonstrated that 36 of them had mild to severe grades of colonic epithelial dysplasia. This was either focal or diffuse in distribution and occurred in flat mucosa, in pseudopolyps, or in regenerating epithelium at the edges of ulcers. These dysplastic changes are regarded as the pathological basis for the malignant potential of schistosomal colitis, and they resemble the changes found in long-standing chronic ulcerative colitis.

Survival and kinetic response of V79-spheroids after exposure to heavy ion beams

Multicellular V79-spheroids and V79-monolayer cultures were irradiated with charged particle beams. The beams studied and their initial extraction energies were carbon (400 MeV/amu), neon (425 MeV/amu) and argon (570 MeV/amu). Survival was measured at a position in the plateau, and at a position in the middle of a 4 cm extended Bragg peak. Relative biological efficiency (r.b.e.) values for survival of spheroid cells at peak positions were high (4.1--4.2) in comparison to those obtained with monolayer cultures (1.8--2.4) of the same cell line. This finding is explained by the fact that three dimensional cell contact, which benefits survival after low LET radiation, does not influence survival after heavy ion irradiations in the Bragg peak. The peak-plateau r.b.e.-ratio was most advantageous for the carbon-ion beam (= 4.2). Whereas non-cycling inner spheroid cells showed hardly any kinetic changes up to 24 hours after heavy ion irradiation, outer cycling spheroid cells were arrested in G2 + M within a few hours after exposure.