Structural comparison of the Autographa californica nuclear polyhedrosis virus-induced RNA polymerase and the three nuclear RNA polymerases from the host, Spodoptera frugiperda

A partial subunit structure has been determined for the novel RNA polymerase that is induced in fall armyworm (Spodoptera frugiperda) cells upon infection with the Autographa californica nuclear polyhedrosis virus (AcNPV). The putative structure includes nine polypeptides; the complexity of this structure is in accord with the high sedimentation coefficient (15S) estimated for this enzyme. A comparison of the putative structure of the virus-induced polymerase with those of the three host nuclear RNA polymerases shows that the structure of the viral polymerase is apparently unlike any of the host nuclear polymerases. This conclusion is reinforced by immunoblot experiments that show no cross-reactivity between the virus-induced polymerase and an antiserum directed against Drosophila RNA polymerase II. The virus-induced RNA polymerase appears at the onset of the late phase of infection and still appears when viral DNA synthesis is blocked by aphidicolin. Thus, the virus-induced polymerase seems to be composed of early viral products.

Induction of DNA polymerase activities in the regenerating rat liver

The levels of DNA polymerase alpha, DNA polymerase delta, and its accessory protein, proliferating cell nuclear antigen (PCNA) were examined in the regenerating rat liver. The levels of DNA polymerase alpha and delta activities in regenerating liver extracts were determined by the use of the DNA polymerase alpha specific inhibitor, BuAdATP [2-(p-n-butylanilino)-9-(2-deoxy-beta-D-ribofuranosyl) adenine 5'-triphosphate], and monoclonal antibodies. These reagents showed that the total DNA polymerase activities increased ca. 4-fold during regeneration and that the fraction of DNA polymerase delta activity at the peak was 40% of the total DNA polymerase activity. Immunoblots and inhibition studies using specific antibodies showed that DNA polymerase delta and epsilon and PCNA were concomitantly induced after partial hepatectomy. The levels of both DNA polymerase delta and epsilon and PCNA reached their maxima at 24-36 h post hepatectomy, i.e., at the same time that in vivo DNA synthesis reached its peak. Partial purification and characterization of DNA polymerases delta and epsilon from the regenerating rat liver were also performed. These observations suggest that the variation of DNA polymerase delta and epsilon and PCNA during liver regeneration is closely related to DNA synthesis and is consistent with their involvement in DNA replication.

[Surgical and anesthetic mortality in Mackay Memorial Hospital 1988-1989]

The mortality associated with 52128 anesthetics administered over two years (1988-1989) at Mackay Memorial Hospital, Taipei, was reported. The frequency of death to which anesthesia contributed was 0.4/10000 (2 cases in 52128 anesthetics). The total mortality rate from surgery within one week was 0.2% (105 cases in 52128 anesthetics). Anesthetic deaths were responsible for 1.9% of the total mortality. There were 25 cases of cardiac arrest with 18 fatal cases (7 cases were recovered after cardiopulmonary resuscitation). The causes of cardiac arrest during anesthesia included anesthetic factors (24%), surgical factors (24%) and patients' pathological factors (52%).

Examination of the roles of selenium in the Kaschin-Beck disease. Cartilage cell test and model studies

The Kaschin-Beck Disease, an endemic disease in China, occurs in low-selenium areas. Using human embryonic cartilage cell as a system, the effect of selenite and another etiological factors, such as, organic matters in water, and grain from disease regions, were studied. It was shown that Se(IV), as well as superoxide dismutase, could prevent the cells from damage by organic matters, and increase the activity of GSHpx and decrease the production of lipid peroxide. A model test of adrenalin autooxidation was carried out, and it was found that the oxy-radical can be eliminated by Se(IV). Thus, it was assumed, that selenium was a protective factor and free radical scavenger for Kaschin-Beck Disease.

Protective effect of zinc-induced metallothionein synthesis on gentamicin nephrotoxicity in rats

Wistar rats were used to study the protective effect of zinc-induced metallothionein (MT) synthesis on gentamicin nephrotoxicity. We found that s.c. pre-injection of ZnSO4 (Zn 10 mg/kg/day) for 5 days could ameliorate proximal tubular necrosis and acute renal failure caused by an 8-day s.c. injection of gentamicin (100 mg/kg/day), while preinjection of saline instead of zinc or zinc and gentamicin together could not. In the zinc-pretreated rats (n = 6), renal cortical metallothionein level was significantly higher than that of normal (n = 8, p less than 0.001) and the saline controls (n = 6, p less than 0.001). Since MT is a scavenger of hydroxyl radical, it is proposed that hydroxyl radical plays a role in the pathogenesis of gentamicin nephrotoxicity and that preinjection of zinc could ameliorate gentamicin nephrotoxicity via the induction of renal cortical MT synthesis.

A comparison of newly and previously diagnosed diabetics in Taiwan

Between 1985 and 1986, during a population survey of diabetes in 1 urban and 5 rural areas of Taiwan, a total of 11,478 adults aged 40 or older were screened. Capillary whole blood glucose was determined with a glucometer (Ames Co.) The diabetic criteria followed the WHO designations. From this survey, a comparison of 225 newly diagnosed and 383 previously diagnosed diabetics was conducted. Multiple regression analysis revealed a highly significant correlation for all diabetics with regard to age, body mass index, family history and hypertension, but no specific correlation to habitat. Mean fasting glucose levels in previously and newly diagnosed diabetics were 172 and 158 (males 158 vs 147 and females 184 vs 165) mg/dl, respectively, which suggest that treatment is apparently inadequate in this population. The prevalent rate (%) of retinopathy for previously and newly diagnosed diabetics was 45.2 and 28.3 (males 42.8 vs 33.3 and females 47.5 vs 24.8), respectively. The prevalence is as common as those reported in western countries. In conclusion, previously diagnosed diabetics had higher fasting glucose concentrations and prevalent rates of retinopathy than newly diagnosed diabetics, and these findings were particularly prominent in females.

[Pulmonary lavage for alveolar proteinosis. A case report]

Pulmonary alveolar proteinosis is characterized by an amorphous lipoproteinaceous material filling the acini of the lung, resulting in hypoxemia. At present, the most effective treatment for alveolar proteinosis is lung lavage. Here, we report the first case in Taiwan treated with this method. A 38-year-old male with a 6-month history of cough and increasing breathlessness was transferred from another hospital. On admission, his arterial oxygen tension was 51 mmHg when breathing room air. Chest X-ray films showed diffuse infiltration of both lung fields. Transbronchoscopic lung biopsy was consistent with alveolar proteinosis, therefore the patient was submitted to pulmonary lavage. Under general anesthesia, the patient was intubated with a left-sided double lumen endotracheal tube, and lavage of the right lung was repeated with 0.9% saline until the washing became clear. At the end of the procedure, the patient was extubated after making strong respiratory efforts. Several days later, the left lung was lavaged using the same technique. The mechanical washing of amorphous material from alveoli by pulmonary lavage is of great benefit in relieving hypoxemia. Judicious use of lung lavage is effective and safe for patient with alveolar proteinosis.

Specific chromosome changes and nonoccupational exposure to potentially carcinogenic agents in acute leukemia in China

Cytogenetic studies were performed on 44 Chinese patients with acute leukemia. A high percentage of patients (37.5%) with t(8;21), t(15;17) or 17q- (in poorly banded preparations), and abnormalities involving 11q23 were noted in 32 unselected patients with ANLL. A similar high percentage was previously reported in Japan and in South Africa but not in western countries. Data on casual or other non-occupational exposure to potentially carcinogenic agents were obtained by interview with the patients at their first presentation. Most patients with these three major chromosomal changes had a history of exposure, whereas most other patients did not (p = 0.01). Patients with ANLL-M3 were more often exposed than were the other patients (4/6 vs 8/38, p = 0.03). The only common exposure was to organophosphate insecticides. Twenty seven cases of therapy-related leukemia were collected from the Chinese medical literature, and 12 out of 22 (55%) cases in which subtypes were specified were ANLL-M3. This was significantly higher than the percentage of M3 in de novo ANLL in China and also higher than that of therapy-related leukemia from western countries. Two patients had siblings who died of leukemia at a similar age. The two patients showed inv(16) and del(6q) respectively.

The influence of proglumide, a putative CCK antagonist, on cerebral ischemia in gerbil

Studies were conducted to clarify the possible role of CCK in cerebral ischemia and to evaluate the effects of proglumide, a competitive and reversible CCK antagonist, as a potential therapeutic or prophylactic tool in the treatment of cerebral ischemia. Proglumide at the doses of 10, 50 and 150 mg/kg was administered to gerbils before unilateral carotid ligation, and its effect on stroke index score, incidence and mortality rate was observed. Our results show that proglumide injected prior to carotid ligation at the dose of 150 mg/kg significantly reduces both incidence and mortality rate and changes the distribution of the stroke index score in gerbils. There was a significant inverse relationship between the dose of proglumide and both incidence and mortality: the greater the injection dose of proglumide, the lower the incidence and mortality. These results suggest that CCK may be involved in the pathological processes of cerebral ischemia and proglumide or related compounds prove to be effective in the pharmacological prophylaxis of ischemic brain damage.

Comparative vestibular toxicity study with 3-O-demethylfortimicin A disulfate and gentamicin sulfate in cats

3-O-demethylfortimicin A disulfate (ODMF), a novel aminocyclitol antibiotic, was administered subcutaneously for three months to groups of male and female cats at 15, 30 or 60 mg base/kg/day. Gentamicin sulfate (GS) at doses of 6 and 13 mg base/kg/day served as a reference compound. Signs of vestibular toxicity were considered to include persistent unsteady gait and stance, impaired righting reflex and abnormally diminished postrotatory vestibular nystagmus. Renal toxicities produced by ODMF and GS were also determined and compared. ODMF at 15 and 30 mg base/kg/day produced no signs of vestibular toxicity, while a dosage of 60 mg base/kg/day of ODMF produced vestibular toxicity in 7/10 cats. Three affected male cats died or were killed in moribund condition between study days 49 and 64. Vestibular toxicity was observed in 10/10 cats treated with GS at 13 mg base/kg/day and in 3/10 cats at 6 mg base/kg/day. All ten cats treated with GS at 13 mg base/kg/day died or were killed in moribund condition between study days 30 and 81. The deaths and moribundity in cats treated with ODMF or GS were attributed to renal toxicity. The vestibular toxicity and nephrotoxicity produced by ODMF and GS were more severe in male cats than in females. In conclusion, ODMF given at doses up to 60 mg base/kg/day for three months induced comparatively less vestibular toxicity and renal pathology than did GS at a dose of 13 mg base/kg/day.

Carotid ligation alters cholecystokinin-8 (CCK-8) immunoreactivity in gerbil brains

The unilateral or bilateral carotid arteries were ligated in gerbils used as a model of cerebral ischemia. The effect of different times of bilateral ischemia on the content of CCK-8 in fore regions of gerbil brain and the effect of 30 min of unilateral ischemia on the content of CCK-8 of the same regions in gerbils with or without neurological signs were observed. Our results show that the content of CCK-8 of cortex, basal ganglia, thalamus and hypothalamus decreased significantly. But, in brain stem it remained basically unchanged no matter whether the ischemia was unilateral or bilateral. This suggests that there is a close relationship between CCK-8 and cerebral ischemia, and raises the possibility that CCK-8 may be involved in cerebral ischemia through a yet unclear mechanism.

HLA polymorphisms in a Han Chinese population of Sichuan

This study reports the phenotype frequencies (PF) and gene frequencies (GF) of a homogeneous Sichuan Han Chinese population by typing of unrelated 229 individuals and 16 families for HLA-A, B, C, DR and DQ antigens. The frequencies of Bw67, Bw71, DRw12, DRw13 and DRw14 are the first to be reported in Chinese. Two two-locus haplotypes with significant linkage disequilibrium among the Sichuan have also been listed.

Bioavailability of selenium to residents in a low-selenium area of China

For 8 wk 5 groups of 10 men each were given 0.5 g/day DL-methionine, 150 micrograms Se/day as sodium selenite with or without methionine or 150 micrograms Se/day as selenomethionine with or without methionine. Twenty subjects received placebo as controls. Initially plasma Se rose more rapidly than RBC Se. Increases in Se levels were significantly greater with selenomethionine than with the selenite supplement. In the placebo and methionine supplemented groups neither plasma nor RBC Se varied significantly over the course of the study. Supplementation with selenium resulted in marked increases in plasma and RBC GSH-Px within 2 and 4 wk, respectively. Plasma and RBC GSH-Px activity did not differ significantly between Se-supplemented groups. These studies suggest that selenomethionine-Se was more effective in raising plasma and RBC Se than was selenite-Se. Methionine supplements may increase the bioavailability of selenium in severely deficient subjects.

Selenium intake and metabolic balance of 10 men from a low selenium area of China

Selenium intake and urinary and fecal Se excretion of 10 healthy men from a low Se area in China were determined for three consecutive days, in summer, fall, and winter of 1983, and the spring of 1984 while self-selected diets were being consumed. Mean daily Se intake was 8.8 micrograms/day with a range of 2.3-35.5 micrograms/day, and was far below the recommended range of safe and adequate Se intake of 50-200 micrograms Se/day (National Academy of Sciences/National Research Council). Mean urinary and fecal Se outputs were 3.7 and 3.4 micrograms Se/day, respectively. Mean Se balance during this time was +1.8 micrograms Se/day. Apparent absorption of Se approximated 57%. The low Se intake in this area is a cause for concern since the residents of Molimo may be at risk for Se deficiency diseases.

Tulobuterol: one-month intravenous safety studies in rats and dogs

Tulobuterol was given intravenously to rats and dogs at dosages of 1, 5, or 25 mg/kg/day and 0.6, 2, or 6 mg/kg/day, respectively. The no-toxic-effect dosages were 5 mg/kg/day in rats and 6 mg/kg/day in dogs. Two rats died at 25 mg/kg/day. Convulsions, jerking movements, hyperactivity, tremors, hypoactivity and ptyalism were observed in rats given 25 mg/kg/day. Restlessness, ptyalism and hypoactivity were also observed in dogs at 2 and 6 mg/kg/day. Cutaneous and/or mucosal erythema were observed in rats and dogs at all dosages. Increased body weight gain occurred in drug-treated rats and in mid- and high-dose female dogs. Slight elevations in serum creatinine and BUN were seen in rats and dogs at the highest dosages. Heart weights were increased in rats at all dosages after 1 month of treatment and in rats given 25 mg/kg/day after 2 weeks of recovery. There were no treatment-related morphologic changes in either species.