Fos expression in GHB-induced generalized absence epilepsy in the thalamus of the rat

Using the model of gamma-hydroxybutyrate (GHB)-induced generalized absence epilepsy, the present work investigated the distribution of fos oncoprotein expression in the rat thalamus with fos antibody immunohistochemistry. Thirty minutes after absence-like seizures, some fos-immunoreactive cell nuclei were found in bilateral thalamic paraventricular nuclei (PV). After a further 30 min, a massive bilateral induction of fos was observed in the lateral habenular nucleus (LHb), the PV, the rhomboid thalamic nucleus, and the intralaminar nuclei of the thalamus. These results suggest that the LHb and the midline and intralaminar thalamic nuclei may very likely be involved in the pathophysiology of absence seizures.

Hormonal actions during oocyte maturation influence fertilization and early embryonic development

On the basis of evidence just reviewed, the hormonal requirements during IVM of mammalian oocytes for fertilization and developmental competence may be summarized as follows: 1. Nuclear maturation occurs "spontaneously," without follicular factors or hormones, in all mammalian species. 2. Cumulus cells are necessary during nuclear maturation in culture for fertilization and developmental competence. Their effect is enhanced by the addition of serum or follicular fluid to the maturation medium. 3. FSH retards nuclear maturation, perhaps thereby enhancing subsequent developmental competence by allowing more time for cytoplasmic maturation to occur before fertilization. The effects of FSH are mediated, in part, by soluble factors from cumulus or granulosa cells. 4. FSH in vivo before culture or added in vitro to IVM culture media enhances fertilization and stimulates steroidogenesis (progesterone and estradiol) in cumulus cells. Blockade of steroidogenesis prevents the enhancing effect of FSH on fertilization. Progesterone can substitute for FSH in enhancing fertilization of rat oocytes. 5. Other hormones enhance beneficial effects of FSH, with some apparent species differences: a. Rat: Progesterone may mediate the FSH effect. b. Cow, rabbit: Estradiol enhances the beneficial effect of FSH. c. Rabbit: Prolactin further enhances the effects of estradiol and FSH. d. Human: No evidence is available on the possible synergism between steroids and gonadotropins in enhancing in vitro maturation. It is clear that further research is required to elucidate the mechanisms of action of all the hormones that have been observed to influence oocyte maturation, and to establish the physiologic significance of most of these, particularly in species other than laboratory rodents. Major benefits to animal production and human health are likely to accrue from such research.

Incidence survey of leukemia in China

A nationwide cooperative incidence survey of leukemia was carried out from 1986 to 1988 in a cooperative survey network covering 46 investigating areas. More than 60 million person-years were supervised and 1670 new cases identified. The annual incidence of leukemia was 2.76/10(5), and the 95% confidence interval of the population rate ranged from 2.63/10(5) to 2.89/10(5). The incidences in oil fields and polluted areas were significantly higher than those in other areas. The incidence of acute nonlymphocytic leukemia (ANLL) was 1.62/10(5); acute lymphocytic leukemia (ALL), 0.69/10(5); chronic myelocytic leukemia (CML), 0.36/10(5); chronic lymphocytic leukemia (CLL), 0.05/10(5); and special types, 0.03/10(5). The incidence and constituent ratio of CLL were significantly lower than those in Europe and America. A peak of ALL incidence before age 10 was seen; this rate then declined with increasing age until 30. However, the incidences of other leukemias rose with age, reaching peaks at old age (50-70). The leukemia rate in males was significantly higher than in females, both in youth (10-29) (caused by ALL) and at age old (mainly caused by ANLL). The incidences of ANLL subtypes (including M2b) are reported.

[Isolation and characteristics of Borrelia burgdorferi from Ixodes persulcatus]

We reported the detailed characteristics of Lyme disease spirochetes (Borrelia burgdorferi), strain H7, isolated from Ixodes persulcatus in Heilongjiang. Cells of strain H7 were 9.8--26.5 microns long and 0.13--0.35 microns wide. There were 1--11 waves with a wavelength of 1.2--3.0 microns and an amplitude of 0.59--1.13 microns. Direction of spires was left. Seven flagella were inserted subterminally at each end of the cell and ends were pointed. 31 degrees C was the optimum cultural temperature in vitro. The major constitutional and antigenic proteins were 21k, 32k and 34k proteins. H7 could react on the patient sera of Xinjiang and Heilongjiang with IFA and western blot. These findings demonstrated that strain H7 belonged to species Borrelia burgdorferi, but was a new "subtype" which differed from the strains isolated from other areas and vectors.

[Malondialdehyde-modified-low density lipoprotein in diabetes mellitus]

Malondialdehyde-modified-low density lipoprotein (MDA-LDL), lipid peroxide (LPO), lipid and fasting blood glucose (FBG) were studied in 42 diabetic patients and 20 age-matched controls. The results revealed that both MDA-LDL per L serum and MDA-LDL per mol LDL-C of diabetics were higher than those of controls. MDA-LDL/L tended to be much higher in diabetic patients with vascular disease and hyperlipidemia. There was a positive correlation between MDA-LDL/L and LPO, LDL-C, TC, respectively.

Use of MG series monoclonal antibodies in the diagnosis and experimental targeting therapy of gastric cancer

In order to facilitate early diagnosis and improve the treatment of gastric cancer, 12 murine hybridoma cell lines capable of producing monoclonal antibodies (mAb) against gastric cancer were established. These monoclonal antibodies were used in histopathological diagnosis, cytological and serological diagnosis, and radioimmunoimaging (RII). Also, immunoconjugates and immunoliposomes were produced by linking these antibodies with various anticancer agents. In vitro and in vivo studies in mice were carried out to investigate the possible uses of these antibodies in experimental targeting therapy of gastric cancer. This paper presents a review of these studies.

[Relationship between the bacterial resistance induced by rifamdin and the RNA polymerase]

The results of our experiment in vitro showed that the activity of standard RNA polymerase decreased while the concentration of RFD and RFP increased, indicating that the target site of action of RFD was similar to that of RFP on RNA polymerase. Incorporation of [3H] UR into the RNA of sensitive cells of S. sureus and E. coli was strongly inhibited by RFD, but RFD did not affect the resistant strains. In purified DNA-dependent RNA polymerase of sensitive and resistant strains, the enzyme activity of sensitive E. coli a S. aureus strains was inhibited by RFD, but RFD did not inhibit that of the resistant strains (except the P. vulgaris). It can be concluded that a decreased susceptibility of RNA polymerase to RFD as well as a decreased permeability of bacterial envelope may induce bacterial resistance to the drug.

[Pathological study of 23 cases of nonfunctional pituitary adenoma]

23 cases of nonfunctional pituitary adenoma were studied with light and electron microscopy as well as with immunohistochemical stains PAP technique. Under routine light microscopy, 17 cases were chromophobic adenomas; anyhow, electron microscopy showed that there were 6 cases of oncocytoma; 7 cases of undifferentiated cell adenoma; 4 cases of gonadotropic adenoma; 4 cases of mixed adenomas 1 cases of sparsely granulated GH cell adenoma and 1 case of sparsely granulated PRL cell adenoma. Immunohistochemical stain showed: null cell adenomas 7 cases, FSH cell adenoma 3 cases, LH cell adenoma 1 case, GH cell adenoma 2 cases and other mixed adenoma 10 cases. Therefore, the nonfunctional pituitary adenoma is actually a mixture, and the null cell adenoma was only about 1/3 in this series. Among them, most of the hormones gave no function expression themselves.

Studies on zona hardening in rat oocytes that are matured in vitro in a serum-free medium

The present study confirms that zona pellucidae of rat oocytes became resistant to chymotrypsin digestion (zona hardening) after undergoing in vitro maturation (IVM) in a serum-free medium. However, zona hardening did not occur when empty zonae without oocytes were cultured in the same IVM conditions, suggesting that oocyte-derived factor(s) is responsible for zona hardening in oocytes matured in the serum-free medium. Zona hardening occurred primarily after dictyate oocytes were cultured for 6-8 hours in the IVM medium without serum. Zona hardening could be prevented or alleviated if oocytes were cultured in the IVM medium containing bovine foetal calf serum, a soybean trypsin inhibitor, or beta-mercaptoethanol, and in vitro fertilization rates for such oocytes were normal. Possible mechanisms of the phenomenon of zona hardening in oocytes matured in serum-free conditions are discussed in relation to its possible relevance to the cortical reaction and the physiological block to polyspermy.

[In vitro nucleation factors--mucus glycoprotein and proteins: changes and mechanisms in the process of sludge and gallstone formation]

Both mucus glycoprotein (MGP) and proteins are in vitro nucleation factors. Biliary sludge proved to be a precursor of gallstones. In this study, the MGP in gallbladder bile (GB) and the RNA content of the membrane-bound polyribosome in gallbladder epithelium were significantly higher in the sludge group than that in gallstone and control group. These facts demonstrated the increased synthesis and secretion of glycoproteins in the prestone stage. The RNA content of free polyribosome in the sludge group was also significantly greater than that in the control group so that in prestone stage there was an increase of cell proliferation in the gallbladder epithelium. Patients with sludge and cholesterol gallstones had significantly higher protein concentrations in GB than those without gallstones or with pigment stones. The gallbladder-hepatic bile ratio of proteins was significantly less than that of cholesterol, and there was a highly positive correlation between glycoproteins and proteins in GB. Therefore, the only reasonable explanation for the higher protein content in these two kinds of patients was that the mucus selectively inhibited protein absorption in the gallbladder. The increases in MGP and protein content in GB during the embryonic stage of gallstones might play a significant role in the formation of both cholesterol and pigment gallstones.

Differences in the DNA supercoiling response of irradiated cell lines from ataxia-telangiectasia versus unaffected individuals

In this study the manifestation of DNA damage at the nucleoid level was examined in several AT cell lines using an image analysis system to directly visualize and measure the changes in DNA loop size which occur when increasing concentrations of propidium iodide (PI) are used to titrate the DNA supercoiling response (the 'fluorescent halo assay'). This response consists of a relaxation (0.5-7.5 micrograms/ml PI) and rewinding phase (10-50 micrograms/ml PI), the latter of which is impaired by the presence of DNA strand breaks in irradiated cells. In addition to the inhibition of DNA rewinding seen immediately after irradiation at 0 degrees C, the supercoiling response of AT diploid fibroblasts indicated an increased amount of DNA unwinding compared to fibroblasts from unaffected individuals. This difference appeared to saturate, since the excess in DNA loop size over that seen in irradiated fibroblasts from unaffected individuals remained constant after 5 Gy. These results may reflect a greater instability of the DNA-nuclear matrix attachment points in irradiated AT fibroblasts. The DNA supercoiling response in irradiated transformed AT fibroblasts and AT lymphoblasts did not differ from that observed in unaffected cells of the same type. However, all of the immortalized cell lines (AT and unaffected) had inherently larger DNA loop sizes than diploid fibroblasts and exhibited excess unwinding after irradiation.

Peptidergic Innervation of the Mammalian Anterior Pituitary

The anterior pituitary is regulated by humoral and probably also by neural factors. Immunocytochemical studies have demonstrated substance P-, calcitonin gene-related peptide-, and galanin-like immunoreactive nerve fibers in the pars distalis of several mammalian species, and synapses have been identified on gland cells.

Peptidergic innervation of the pars distalis of the adenohypophysis

Substance P-like immunoreactive nerve fibers have been found in the pars distalis of the adenohypophysis in the monkey, dog, and rat. Calcitonin gene-related peptide-like immunoreactive nerve fibers have also been identified in the dog and rat. The peptidergic fibers are closely related to the glandular cells with synaptic contacts demonstrated between them. It is suggested that neural factors may be directly involved in the regulation of the activities of the anterior pituitary.

Leukocyte redistribution and eicosanoid changes during the autoperfused working heart-lung preparation

We studied the role of leukocyte redistribution and eicosanoid changes in the early stages of instituting 16 rabbit autoperfused working heart-lung preparations (AWHLP). Physiological changes occurring during the transition from the intact animal to the AWHLP may determine the survival and viability of the organ blocks for transplantation. White blood cell (WBC) count decreased from 5,160/microL to 1430/microL (P less than .01) at 60 min of autoperfusion. Differential WBC counts performed in ten of these AWHLP revealed a 63% decrease in lymphocyte count and an 88% decrease in the granulocyte count at 60 min. Thus, the predominant leukocyte remaining in the circulation was the lymphocyte. Blood samples were collected from the intact animal and from the AWHLP for assay of the stable metabolites of thromboxane A2 (TxA2) and prostacyclin (PGI2). Transition from the in situ heart-lung block to the in vitro AWHLP stage caused significant changes in these metabolites. The PGI2 metabolite 6-ketoprostaglandin F1a (6KPGF1a) increased from 2680 +/- 487 to 4339 +/- 478 (pg/mL), P less than .05, while the TxA2 metabolite, thromboxane B2 (TxB2) decreased from 618 +/- 105 to 289 +/- 63 (pg/mL). However, assays of 11-dehydro-TxB2 (11-DHT), a longer lived metabolite of TxA2 (n = 7) increased (668.4 +/- 84.6 to 946.4 +/- 43.7, P less than .05). The transition from the in situ heart-lung block of the intact animal to the AWHLP involves significant physiological changes. Redistribution of leukocytes occurs with a predominant decrease in the granulocyte count, while levels of bioactive lipid mediators show a distinct large rise in the PGI2 metabolites and a lesser increase in TxA2 metabolites.(ABSTRACT TRUNCATED AT 250 WORDS)