Noncovalent Association Thermodynamics of Turn-On Fluorescent Probes with Human Serum Albumin: Dual-Concentration Ratio Method

Efficient quantification of the affinity of a drug and the targeted protein is critical for strategic drug design. Among the various molecules, turn-on fluorescent probes are the most promising signal transducers to reveal the binding strength and site-specificity of designed drugs. However, the conventional method of measuring the binding ability of turn-on fluorescent probes by using the fractional occupancy under the law of mass action is time-consuming and a massive sample is required. Here, we report a new method, called dual-concentration ratio method, for quantifying the binding affinity of fluorescent probes and human serum albumin (HSA). Temperature-dependent fluorescence intensity ratios of a one-to-one complex (L ⋅ HSA) for a turn-on fluorescent probe (L), e. g., ThT (thioflavin T) or DG (dansylglycine), with HSA at two different values of [L]0 /[HSA]0 under the constraint [HSA]0 >[L]0 were collected. The van't Hoff analysis on these association constants further resulted in the thermodynamic properties. Since only two samples at different [L]0 /[HSA]0 are required without the need of [L]0 /[HSA]0 at a wide range, the dual-concentration ratio method is an easy way to greatly reduce the amounts of fluorescent probes and proteins, as well as the acquisition time.

Regulation of polyribosome formation and protein synthesis in the uterus. Effect of ovariectomy and administration of oestradiol-17beta on the amino acid-incorporation activity in vitro and the cytoplasmic concentration in vivo of polyribosomal preparation

1. The hormonal regulation of cytoplasmic protein synthesis in the uterus is described. Polyribosomal preparation from uteri of normal or ovariectomized rats was isolated by procedure 3 and assayed for [(14)C]leucine-incorporation activity in the cell-free system, as described by Teng & Hamilton (1967). 2. Ovariectomy of normal animals caused, 3 weeks after surgery, a 50-60% increase in the amino acid-incorporation activity in vitro of uterine polyribosomal preparation, but a 90-95% decrease in the cytoplasmic concentration in vivo of the preparation. 3. Administration of 10mug. of oestradiol-17beta to ovariectomized rats at zero time caused, 10-12hr. later, a 100% stimulation in amino acid-incorporation activity in vitro of the uterine polyribosomal preparation. From 12hr. to 36hr. after hormone administration, the activity in vitro of the preparation decreased. If a second dose of hormone was administered at 36hr., the activity in vitro of the preparation continued to decrease, and approached at 48hr. and 72hr. the lower activity observed for the preparation from normal animals. The cytoplasmic concentration of polyribosomal preparation increased by 600-700% under these experimental conditions. If a second dose of oestradiol-17beta was not administered at 36hr., the initially elevated cytoplasmic concentration of the preparation decreased by 50% from 36hr. to 72hr., and the activity in vitro of the preparation was not fully depressed to the ;normal' value. 4. Pretreatment of ovariectomized animals with actinomycin D or cycloheximide abolished 80-90% of the stimulatory effects of hormone treatment on the amino acid-incorporation activity in vitro and cytoplasmic concentration in vivo of uterine polyribosomal preparation. 5. Two major conclusions are drawn from the results reported: that during early oestrogen action new polyribosomes having amino acid-incorporation properties different from those of the old ones appear and accumulate in the cytoplasm of the uterus; and that the regulation of cytoplasmic protein synthesis in the organ by oestrogen is of an indirect nature, with dual effects of the hormone on genetic transcription resulting in turn in a regulation of the rate and amount of genetic translation.

Regulation of polyribosome formation and protein synthesis in the uterus. Isolation of cytoplasmic ribonucleoprotein particles and the principal properties of the cell-free protein-synthesizing system

1. Three procedures for isolating ribonucleoprotein particles from the cytoplasmic fraction of rat-uterus homogenates are described. By procedure 1, ribonucleoprotein particles were isolated in the presence of 5mm-Mg(2+) and 25mm-K(+), and the postmitochondrial supernatant fraction was made to 1.3% (w/v) in potassium deoxycholate. About 50% of the RNA and protein of the microsomal fraction was recovered in the monomeric ribosomes isolated. By procedure 2, ribonucleoprotein particles were isolated in the presence of 10mm-Mg(2+) and 0.1m-K(+), and in the absence of detergent. The ribosomes obtained were primarily polymeric, but recovery of microsomal RNA and protein was only 32%. By procedure 3, ribonucleoprotein particles were isolated according to procedure 1 but without the use of detergent. A mixture of polymeric and monomeric ribosomes was obtained, and the recovery of microsomal RNA and protein was about 60%. 2. Uterine polymeric and monomeric ribosomes, isolated by procedure 3 and designated ;polyribosomal preparation', were examined for protein-synthesizing capabilities. The principal properties of the cell-free protein-synthesizing system containing the polyribosomal preparation are described. The efficiency of amino acid incorporation in the complete system incubated for 30min. and containing the polyribosomal preparation was found to be either 2.5 molecules of [(14)C]leucine or 2.2 molecules of [(14)C]-valine incorporated/ribosome. Assay of the preparation in the complete cell-free system containing 10mm-sodium fluoride indicated that 40% of the incorporation activity is a result of initiation of new polypeptide chains and 60% is due to completion of previously existing chains. Monomeric ribosomes obtained by various treatments of the polyribosomal preparation with sodium fluoride, ribonuclease and potassium deoxycholate had decreased incorporation activity in the cell-free system. However, monomeric ribosomes obtained by treatment with sodium fluoride only had an incorporation activity 50% greater than that of monomers obtained by treatment with ribonuclease only. 3. The results indicate that uterine polymeric and monomeric ribosomes are sites of amino acid incorporation in vivo and in vitro. It is concluded that most polymeric and monomeric ribosomes occurring in the cytoplasmic fraction of the uterus are free and unattached to membranes, and that the polyribosomes are relatively unstable.

Differential activation of MAPK during Müllerian duct growth and apoptosis: JNK and p38 stimulation by DES blocks tissue death

To investigate the involvement of the mitogen-activated protein kinases (MAPKs) in c-Jun-mediated Müllerian duct (MD) differentiation, Western immunoblot with antibodies against c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinases (ERK1 and 2), p38, phosphorylated JNK (p-JNK), and p-ERK were used to investigate these kinases in the left and right MDs (LMD and RMD, respectively) of female chicks. The content of these kinases in the LMD and RMD of various stages of embryos was detected by measuring their density in autoradiograms by a Spot-denso-program with Alpha Ease software. In the LMD, the growing embryonic sex tract, the amount of JNK increased from the 8th to 10th embryonic day and reached its highest at the 12th to 18th day. The content of ERK1, ERK2, and p38 remained at the same level throughout development. In the RMD, the apoptotic embryonic sex tract, the level of these four MAPKs showed a linear increase from the 8th to 10th day and then declined at the 12th day. Before the RMD entered the apoptotic stages (10th day of incubation), MAPKs were overexpressed. The findings following the application of p-MAPK antibodies, e.g., p-JNK and p-ERK, mirrored the result showing that differential activation of MAPKs existed in the LMD and RMD. When the RMD entered the apoptotic stages (13th to 18th day of incubation), the reduction in JNK activity was higher than that of the other three kinases. The apoptotic death of RMD was prevented by in vivo diethylstilbestrol treatment, which restored the level of JNK, p-JNK, and p38. No stimulatory effect was found for ERK and p-ERK.

Differential expression of c-Jun proteins during müllerian duct growth and apoptosis: caspase-related tissue death blocked by diethylstilbestrol

To elucidate whether the differentiation of the Müllerian duct (MD) is mediated by c-Jun proteins, Western immunoblot with c-Jun/sc-45 antibody was used to investigate these proteins in female chick left and right MDs (LMD and RMD, respectively). The content of these proteins (e.g., the 66-kDa, 45-kDa, and 39-kDa forms) in the LMD or RMD of various stages of embryos was detected by measuring their density in autoradiograms by a Spot-denso-program with Alpha Ease software. In the LMD, the growing embryonic sex tract, the content of the 66-kDa and 39-kDa proteins increased to their highest level in 9th to 12th day embryos and then declined thereafter. In the RMD, the apoptotic embryonic sex tract, the content of these proteins also showed a linear increase from the 9th to 10th day and then declined at the 13th day. When the RMD entered the apoptosis stages (14th to 18th day of incubation), these proteins were persistently overexpressed. Another protein (45 kDa) was detected in both ducts only at the 9th to 13th days, and its content was higher in RMD than in the LMD. In parallel to this finding, high caspase-3 activity (determined by the measurement of the fragmented 85-kDa poly ADP-ribose polymerase) was found in the RMD during apoptosis. The apoptotic death of RMD was prevented by in vivo diethylstilbestrol treatment, which inhibited the overexpression of the 66-kDa and 45-kDa proteins, the fragmentation of DNA, and the activity of caspase-3. No inhibitory effect was found for the 39-kDa protein.

Protooncogenes as mediators of apoptosis

Apoptosis has been well established as a vital biological phenomenon that is important in the maintenance of cellular homeostasis. Three major protooncogene families and their encoded proteins function as mediators of apoptosis in various cell types and are the subject of this chapter. Protooncogenic proteins such as c-Myc/Max, c-Fos/c-Jun, and Bcl-2/Bax utilize a synergetic effect to enhance their roles in the pro- or antiapoptotic action. These family members activate and repress the expression of their target genes, control cell cycle progression, and execute programmed cell death. Repression or overproduction of these protooncogenic proteins induces apoptosis, which may vary as a result of either cell type specificity or the nature of the apoptotic stimuli. The proapoptotic and antiapoptotic proteins exert their effects in the membrane of cellular organelles. Here they generate cell-type-specific signals that activate the caspase family of proteases and their regulators for the execution of apoptosis.

c-fos protein expression in apoptotic rat spermatocytes induced by gossypol

Proto-oncogene products such as c-fos protein with a molecular weight of 62 kDa have been identified in rat spermatocytes. In this study, cellular levels of c-fos proteins in spermatocyte, either with or without gossypol exposure, were quantitatively detected by Western immunoblot and a computer-controlled Spot-denso-program with an IS-1000 Digital Imaging System. Within 0.5-3.5 h (an average of 2 h) of the addition of gossypol, levels of c-fos proteins fell dramatically. The reduction in c-fos proteins occurred 6 h before the apoptosis of spermatocytes in the presence of gossypol. Four hours after exposure to gossypol, the c-fos protein content was overexpressed. The period of c-fos up-regulation lasted for approximately 8 h. The increase in c-fos protein coincided with a high rate of apoptotic cell death. Morphologic structure of the dying cell was revealed by electron microscopy. These results suggest that spermatocyte apoptosis induced by gossypol correlates with biphasic c-fos protein-mediated apoptosis.

Biphasic c-Myc protein expression during gossypol-induced apoptosis in rat spermatocytes

The presence of protooncogene products such as c-Myc proteins in rat spermatocytes has been quantitatively detected by Western immunoblot and a computer-controlled Spotdenso-program with an IS-1000 digital imaging system. Cellular levels of c-Myc proteins in response to gossypol were measured in spermatocytes during the process of gossypol-induced apoptosis. Within 0.5 to 2 h of the addition of gossypol, levels of c-Myc proteins fall dramatically and remain at a low level for the next several hours. The reduction in c-Myc proteins occurs 4.5-6 h before the apoptosis of spermatocytes in the presence of gossypol. Between 3 and 5 h after exposure to gossypol, the c-Myc protein content returns to preexposure (or higher) levels. In addition, the increase in c-Myc proteins occurs 1.5-4 h before the apoptotic death of spermatocytes. An identical pattern of c-Myc protein response to gossypol was also found in total testicular tissue in vitro. These results suggest that spermatocyte apoptosis induced by gossypol is correlated with biphasic c-Myc protein expression. This article present some hypothetical models with which to explain c-Myc protein-mediated apoptosis.

Reversible changes in the content of cellular and microtubular tubulin in spermatogenic cells after gossypol treatment

After exposure of young male rats to gossypol acetic acid for various times, a reduction in the content of cellular and microtubular beta-tubulin was found in spermatocytes and spermatids. The content of tubulin was measured by enzyme-linked immunosorbent assay (ELISA). The results were expressed as micrograms tubulin/100 micrograms total protein and compared with those of the control rats. After drug treatment for 2, 6, 12, and 20 weeks, the content of total cell tubulin in spermatocyte was reduced by 2.4%, 8.8%, 52%, and 61%, respectively; whereas the content of tubulin in spermatid was reduced by 7.4%, 36%, 70%, and 72%, respectively. At the same time length of drug treatment, the content of microtubular tubulin in spermatocyte was reduced by 1.6%, 13%, 58%, and 61% in comparison to the reduction rate of 5%, 37%, 69%, and 77%, respectively, for spermatid. These results indicated that the tubulins associated with spermatids were more vulnerable to gossypol than that of the spermatocytes. Eight weeks after withdrawal of the drug treatment, the content of tubulin in spermatocytes and spermatids was recovered.

Reversible changes in the content of cellular and microtubular tubulin in spermatogenic cells after gossypol treatment

After exposure of young male rats to gossypol acetic acid for various times, a reduction in the content of cellular and microtubular beta-tubulin was found in spermatocytes and spermatids. The content of tubulin was measured by enzyme-linked immunosorbent assay (ELISA). The results were expressed as micrograms tubulin/100 micrograms total protein and compared with those of the control rats. After drug treatment for 2, 6, 12, and 20 weeks, the content of total cell tubulin in spermatocyte was reduced by 2.4%. 8.8%. 52%, and 61%, respectively, whereas the content of tubulin in spermatid was reduced by 7.4%, 36%, 70%, and 72%, respectively. At the same time length of drug treatment, the content of microtubular tubulin in spermatocyte was reduced by 1.6% 13%, 58% and 61% in comparison to the reduction rate of 5%, 37%, 69%, and 77%, respectively, for spermatid. These results indicated that the tubulin associated with spermatids were more vulnerable to gossypol than that of the spermatocytes. Eight weeks after withdrawal of the drug treatment, the content of tubulin in spermatocytes and spermatids was recovered.

Gossypol-induced apoptotic DNA fragmentation correlates with inhibited protein kinase C activity in spermatocytes

After exposure of cultured rat spermatocytes to gossypol acetic acid for five hours, DNA fragmentation in a ladder pattern was found in the medium and supernatants of cell lysates. The concentrations of gossypol used for the induction of apoptosis ranged from 100 microM to 300 microM. Within this dose range, gossypol was also found to be effective at inhibiting protein kinase C (PKC) activity. This inhibitory effect was demonstrated by measuring the PKC residing in cytosolic and particulate fractions. However, the gossypol-induced inhibition of PKC activity was protected by phorbol 12,13-dibutyrate (PDBu), an activator of PKC. Furthermore, the presence of PDBu prevented gossypol-induced DNA fragmentation. These results suggest that spermatocyte apoptosis induced by gossypol is correlated with the reduction of PKC activity, and that maintenance of PKC basal activity is essential for protecting the spermatocyte from apoptosis.

Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment. VI. Alteration in nuclear factors for interaction with histone gene promoter

This article reports the effects of gossypol at the genomic level in rat spermatogenic cells. After gossypol treatment for various times (8, 12, and 19 weeks), the spermatogonial cells were allowed to rest for 2 to 4 weeks. The function of histone H4 gene promoter (H4GP) in the repopulating pachytene spermatocytes (RPS) was investigated. The sequences of the oligonucleotides for the H4GP binding sites 1 and 2 were synthesized by an ABI-392 DNA synthesizer. RPS and the control pachytene spermatocytes (CPS) were obtained by centrifugal elutriation and subsequently they were used for the preparation of nuclear protein extracts (NPE). The NPE interaction with the DNA fragment of site 1 or 2 was studied by an electrophoresis mobility shift assay (EMSA). EMSA with NPE-CPS revealed ten major gel shift bands for site 1 and 2. The presence of extra unlabelled DNA fragments competed with 6 of the bands. After 2 to 4 weeks recovery from 8, 12, and 19 weeks of gossypol treatment, NPE-RPS failed to shift four bands (b through e) in site 1. These results suggested that gossypol treatment affected the transcription factors for interaction with site 1. On the contrary, no effect was demonstrated in NPE that interacted with site 2. Furthermore, gossypol treatment did not change the nucleotide sequence in the H4GP site 1 and 2.

Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment. V. Inhibition and recovery of microtubular dynein

After oral administration with gossypol acetic acid for various times, young male rats developed a low content of microtubular (or cytoplasmic) dynein in the spermatogenic cells, e.g., spermatids and primary spermatocytes. The content of dynein in the cells was measured by enzyme-linked immunosorbent assay (ELISA) using monoclonal anti-dynein antibody. The results were expressed as ng dynein/10(6) cells and compared with those of the control rats. After gossypol treatment for 8, 12, and 19 weeks, the content of dynein in spermatids was reduced by 61%, 70%, and 68%, respectively; whereas, the amount of dynein in primary spermatocytes was reduced by 37%, 44%, and 31%, respectively. The microtubular dynein associated with spermatids was more vulnerable to gossypol than that of the primary spermatocytes. Immunofluorescent staining technique confirmed the finding that the control cells have more dynein than that of the drug-treated cells. Eight weeks after the withdrawal of the drug treatment, the content of dynein in spermatids and primary spermatocytes was fully recovered. The possible effects of this change in conjunction with the function of microtubules during spermatogenesis and sperm motility are discussed.

Induction of feline acquired immune deficiency syndrome by feline leukemia virus: alteration in response to hormones in the hypothalamic-pituitary-gonadal system

Male kittens who were infected with the feline leukemia virus (FeLV) were found at various times after exposure to contain a sequence of dysfunction in their hypothalamic-pituitary-gonadal (HPG) system. To understand whether the involved endocrine glands in this system were damaged by FeLV, the hypothalamus, pituitary, and testes were tested for hormonal responsiveness in vivo and in vitro. The infected cats were administered with luteinizing hormone-releasing hormone (LHRH) and human chorionic gonadotropin (hCG). Their response to the treatment was studied, and they were then compared with untreated control cats. Normal response to LHRH for the synthesis of follicle stimulating hormone (FSH), luteinizing hormone (LH), and testosterone were found in the infected cats prior to 10 weeks of infection. After 10 weeks, the response was reduced by 25%, 38%, and 42%, respectively. Twelve weeks after infection, the response to hCG for testosterone synthesis was drastically reduced. The control cats, however, demonstrated normal prolonged biphasic patterns of response to hCG. The in vivo administration of the tropic hormones had no effect on the titer of FeLV gs antigen in the blood of the infected cats. The medial basal hypothalamus (MBH) from the control cats and cats in their 13th week of infection were cultured in vitro, with the presence of high K+ ion (60 mM). The control MBH responded to K+ ion stimulation for LHRH release. The K(+)-stimulated release of LHRH in the control MBH was 99% higher than that of the infected MBH. In contrast, the amount of unreleased LHRH in the infected MBH was 74% higher than that of the control MBH. In in vitro culture, the control pituitary gland responded markedly higher to LHRH stimulation for the release of gonadotropins (FHS and LH) than that of the infected one (140% compared with 56% for FSH, and 70% compared with 28% for LH, respectively). Whereas, the amount of unreleased FSH and LH in the infected pituitary gland were 59% and 31%, higher than that of the control gland. These results suggest that (i) the progressive development of neuroendocrine glands' dysfunction is related to viral replication time; (ii) the in vivo and in vitro responses to tropic hormones in the infected endocrine glands are drastically reduced; and (iii) this reduction in hormonal response may be caused by defective regulation of peptide hormonal secretion.

Induction of feline acquired immune deficiency syndrome by feline leukemia virus: immuno- and neuroendocrine dysfunctions

Young cats, when chronically infected with feline leukemia virus (FeLV), developed feline acquired immune deficiency syndrome (FAIDS). The syndrome was associated with a sequence of dysfunctions in the hypothalamic-pituitary-gonadal (HPG) and the immune system, manifested in the reduction of luteinizing hormone-releasing hormone (LHRH), follicle stimulating hormone (FSH), luteinizing hormone (LH), and testosterone in blood plasma. The average FSH and LH (in plasma or lymphocyte), testosterone, and LHRH concentrations in the 20 FeLV-infected cats were measured by radioimmunoassay. The results were compared with those of the 12 control cats that were not FeLV-infected. Four weeks after infection, the plasma LHRH concentration in the infected cats showed a 43% reduction. Five to six weeks after infection, the content of FSH and LH in lymphocyte was reduced by 50% and 28%, respectively, whereas, the plasma FSH and LH was reduced by 52% and 42%, respectively. A significant reduction in testosterone content was detected at Week 11 of infection. The onset of the immuno- and neuroendocrine dysfunctions in FAIDs cats followed this sequence: hypothalamus, lymphocyte, pituitary, adrenal gland, and gonads. Indirect immunofluorescence assay showed the presence of FeLV cytoplasmic antigens in the fibers of the hypothalamic preoptic region and the Leydig cells. The possible causal relationship between the dysfunction of the lymphocyte and HPG systems and the presence of FeLV was discussed.

Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment. IV. The activity for the modification of core histones

Mature male rats were treated with gossypol for 8 weeks. Afterwards, treatment was halted to allow the arrested spermatogonia to revive. Fifteen days after the withdrawal of the drug treatment, the repopulating pachytene spermatocyte (RPS) had a lower level of core histone H3 and H4 acetylation (40 and 55% reduction, respectively) than that of the control pachytene spermatocyte (CPS). The reduction in core histone acetylation was found in histone H3 and H4 but not in H2A and H2B. Forty-five days after the withdrawal of the drug treatment, the inhibitory effect on core histone acetylation was recovered. Both dot-blot and standard liquid assays were used to detect the nuclear histone acetylase activity in RPS and CPS. Fifteen days after the withdrawal of gossypol treatment, the acetylase type A activity in RPS was reduced by 42% when compared to CPS. It has been concluded that after gossypol treatment, the activity for nucleosomal core histones acetylation was selectively inhibited. This effect is related to an inhibitory effect on the histone acetylase activity.

Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment: III. The activity for the transcription of messenger RNA

Mature male rats were treated with gossypol for 8 weeks after which the treatment was stopped to allow the arrested spermatogonia to revive. The arrested spermatogonia in the testes were allowed to develop for 15, 30, and 45 days. The amount of histone H2b, H4 and actin messenger RNA (mRNA) in the repopulated pachytene spermatocyte (RPS) and the control pachytene spermatocyte (CPS) was detected by the dot-blot hybridization technique. Histone H2b mRNA in total testicular RNA is higher than that detected in CPS and RPS. The amount of histone H2b mRNA in 5 micrograms to 10 micrograms of poly (A)+ RNA isolated from CPS is 235% higher than that detected in the RPS. The H2b mRNA content in the resting spermatocytes (15, 30, and 45 days after the withdrawal of gossypol treatment) was inhibited by 68, 72, and 45%, respectively. Histone H2b mRNA transcription in the resting spermatocyte of these 3 time periods was inhibited by 26, 40, and 0%, respectively. Fifteen days after the withdrawal of gossypol treatment, the amount of actin mRNA in RPS was inhibited by 47%. The inhibitory effect of gossypol was rapidly recovered within 30 days after the withdrawal of the drug treatment. It was concluded that after the withdrawal of gossypol treatment, the production of H2b, H4, and actin mRNA in RPS was inhibited. However, the inhibitory effect on the mRNAs' production is reversible. The recovery rate for the mRNAs follows the following order: Actin mRNA greater than H4 mRNA greater than H2b mRNA.

Induction of feline immunodeficiency syndrome by feline leukemia virus: pituitary and adrenocortical dysfunctions

Seven young cats were injected with feline leukemia virus (FeLV); six of them became viremic. All of the viremic cats developed AIDS-related symptoms, i.e. lymphopenia, neutropenia, thymic atrophy, and wasting syndrome, along with an altered pituitary and adrenocortical function. These symptoms closely resemble human AIDS induced by HIV. It was discovered that, after 2 weeks of infection, the average amount of plasma adrenocorticotropic hormone (ACTH) detected in the infected cats was reduced by 29% in comparison with that before the infection. In contrast to the second week, the fifth week of infection showed a 94% increase of plasma ACTH which then dropped back down to 38% after the sixth and seventh weeks. This opposing biphasic pattern of change was also observed in the plasma cortisol content of the infected cats. The amount of change in plasma cortisol did not correlate with the detected increase in plasma ACTH, indicating a weak adrenal response to pituitary action.

Immunocytochemical demonstration of the binding and internalization of growth hormone in GERL of Chang hepatoma cells

The binding and internalization of endogenous growth hormone in Chang hepatoma cells were localized on the cell surface and in the Golgi-endoplasmic reticulum-lysosome (GERL) area by various indirect immunocytochemical labeling techniques, namely, peroxidase or colloidal gold conjugated to secondary antibody, and avidin-biotin complex methods. Rabbit antiserum and monoclonal antibodies raised against HPLC-purified porcine growth hormone were used in this study. In fixed material, antigen-antibody complexes were found to be homogeneously distributed along the cell membrane. Control groups showed negative binding on the cell surface. Trypsin treatment before immunolabeling removed antibody binding completely, but hyaluronidase was ineffective. Pretreatment of lectins did not block the recognition of primary antibody to antigen molecules on cell surface. Internalization of the antigen-antibody peroxidase or gold complexes was demonstrated in the cells, which were immunolabeled at 4 degrees C, and then reincubated for 0-30 min at 37 degrees C before fixation. After reincubation, the internalized ligand complexes were found in vesicles near the cell surface or in the GERL area near the Golgi apparatus which, however, did not label for peroxidase. These findings suggest that the trypsin-sensitive growth hormone, specifically bound and internalized into Chang hepatoma cells, is localized in the GERL instead of the Golgi apparatus and might be involved in the mechanism of tumor cell growth.

Quantitative change in fibronectin in cultured müllerian mesenchymal cells in response to diethylstilbestrol and müllerian-inhibiting substance

I report on the synthesis of fibronectin in the developing chick Müllerian duct mesenchymal cells. Before the differentiation of female chick Müllerian duct, the amount of fibronectin in the cells of the right duct is 44% lower than in the left duct. While after differentiation, the amount of fibronectin in the right duct is 29% lower, as compared to the left duct. Estrogenic hormone diethylstilbestrol (DES) treatment was carried out at the 5th day of incubation when both female Müllerian ducts were undifferentiated. Three days after DES treatment, the regression of the right duct was prevented, and the amount of fibronectin was induced by 89%, while induction in the left duct was 11%. Eight days after DES administration, the amount of fibronectin in the right and left Müllerian duct was induced by 150 and 76%, respectively. After DES treatment in the male embryo, both Müllerian ducts were retained, and the capacity for fibronectin synthesis was preserved. Application of the indirect immunocytochemical labeling technique revealed Müllerian-inhibiting substance (MIS) binding sites on the membrane of the Müllerian mesenchymal cells. The addition of chick MIS in the culture medium reduced the amount of detectable fibronectin in the cultured mesenchymal cells. The synthesis of fibronectin in intestinal mesenchymal cells was not affected by DES or MIS.

Biosynthesis and secretion of fibronectin in the cultured mesenchymal cells of the developing chick müllerian duct

We have developed a method to separate and isolate the mesenchymal cells from the epithelial cells in the left Müllerian duct of the developing chick. We then cultured the mesenchymal cells in a serum-free medium. Through an enzyme-linked immunosorbent assay, we detected fibronectin synthesis and release into the medium at stages of Müllerian duct development. Our results demonstrate that the amount of fibronectin secreted by cultured cells gradually decreased in accordance with Müllerian duct differentiation. Similar observations found in the developing embryonic intestine indicate that the highest fibronectin synthesis occurs during early stages of development, when morphogenetic movement and mesenchymal-epithelial interaction are prominent features of embryonic organ differentiation and growth.

Lectin bindings and diethylstilbestrol effects on the recognition of mullerian inhibiting substance (MIS) on chick mullerian ducts by MIS-antiserum

A high intensity of lectin bindings was demonstrated on the epithelial cells and serosa cells of the regressing right Mullerian ducts (Mds) in the female chick embryos. The strong lectin bindings occurs on, or in the regressing Md cells along with marked surface MIS bindings at the age of day 13. However, at the age of days 5-7 1/2, bindings of lectins were weak. Neither Wheat-germ agglutinin (WGA) or Concanavalin A (Con-A) labelings before MIS-antiserum (MIS-Ab) incubation can block antibody recognitions to the antigens, including MIS and growth hormone at the age of day 13. Our previous studies indicated that after WGA labeling on the surfaces of Md epithelial cells prior to the incubation of MIS-Ab at day 10 did not prevent the recognition of MIS-Ab (Wang 1989). On the contrary, at day 7 1/2, the specific binding of MIS was eliminated after preincubations with lectins and prenatal diethylstilbestrol (DES) treatment at the age of day 5. It is suggested that DES provides a protection to the Mds from MIS-induced regression by preventing the MIS binding to its specific membrane receptors. An increase of extra- and intracellular glycoproteins or carbohydrates of regressing Md epithelial cells were suggested. Internalization of WGA but not MIS molecules was found in Md epithelial cells. The Golgi saccules were negative of lectin bindings.

Antibody against avian müllerian inhibiting substance (MIS) recognizes MIS on rat müllerian duct and human tumor cells

Müllerian inhibiting substance (MIS) on rat Müllerian duct (Md), and four Müllerian-derived tumor cells: HeLa S-3, RL-95.2, A-431 and NIH:OVCAR-3 are recognized by the poly- and mono-clonal avian-MIS-antibodies (A-MIS-Abs) using avidin-biotin complex (ABC) immunolabeling techniques. Internalization of MIS-ligand complexes was successfully detected in HeLa S-3, OVCAR-3 and RL 95.2 cells. Control groups include: (i) the samples omitted primary antibody treatment, (ii) Wolffian duct by side of Md in the genital ridge, and (iii) another two MIS-negative tumor cell lines of non-Müllerian origin: Chang hepatoma ascites cell and mouse myeloma cell (X63-Ag 8.653). Genital ridges from rat embryos of 14d of gestation were removed under dissection microscope, fixed in 2.5% glutaraldehyde in D-PBS of pH 7.2 for 30 min, and sliced into 0.1-0.2 mm thick pieces. A-431, HeLa S-3 and NIH:OVCAR-3 were maintained in OPTI-MEM culture medium, RL-95.2 was cultured in F12 culture medium. The cells were transferred to 24-well flat bottom culture plates with Thermanox tissue culture coverslips. The immunolabeling of fixed and non-fixed samples were processed within the wells. These studies provide first immunocytochemical evidences for the similarity between A-MIS and M-MIS molecules by polyclonal and monoclonal A-MIS-Ab. It has also proved that the tumor cell lines, which were subjects of MIS inhibition of cell growth, showed MIS binding on cell surfaces.

Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment: II. The activity for the synthesis of cellular and nuclear basic proteins

The synthesis of cellular and nuclear basic proteins in the first generation of the repopulated pachytene spermatocyte (RPS) and the control pachytene spermatocyte (CPS) was studied by the incorporation of 3H-arginine into proteins. After pretreatment with gossypol for various lengths of time, the synthetic activity for cellular protein in the RPS was slightly inhibited. In comparison to CPS, on the other hand, the inhibition ranged from 12% to 26% (for gossypol pretreatment from 3 to 12 weeks, respectively). However, the synthetic activity for nuclear basic protein in the RPS was drastically reduced in comparison to that of the CPS. The reduction ranged from 46% to 61% in RPS after receiving gossypol pretreatment for 3 to 12 weeks, respectively. Gel electrophoretic separation of the basic protein extracted from the pachytene cell indicated that the major basic proteins are nucleosomal linker and core proteins, i.e., histone H1, H2A,B, H3, and H4, and with a lesser amount of sperm-specific BP and X1 proteins. After gossypol treatment in the RPS, the synthesis of sperm-specific proteins (BP and X1) and core histones (H2A and H4) became drastically reduced. Finally, the effect of gossypol on the ratio of nuclear basic protein to DNA in RPS and the direct correlation of this ratio to nucleosomal spacing and chromatin structure are discussed.

Biological activity in the repopulating rat spermatocyte after the withdrawal of gossypol treatment: I. The activity for DNA synthesis

Mature male rats were treated with gossypol for various lengths of time after which the treatment was stopped to allow the arrested spermatogonia to revive. Fifteen days after withdrawal of the drug treatment, the arrested spermatogonia entered into the meiotic division and then reached the pachytene stage. The meiotic cells derived from the arrested spermatogonia were the first generation of the differentiated germ cells after long-term gossypol treatment. Centrifugal elutriation technique was used to isolate the repopulating pachytene spermatocytes (RPS) or the control pachytene spermatocytes (CPS) from the rat testis with or without receiving gossypol pretreatment. In vitro culture condition for RPS and CPS was established for the synthesis of DNA by the measurement of 3H-thymidine incorporation. The activity for DNA synthesis in RPS was studied and compared to that of the CPS. It was concluded that after gossypol treatment for various times, the incorporation of 3H-thymidine into the cellular thymidine pool of RPS was not affected. However, the activity for DNA synthesis in RPS was significantly lower than that in the CPS. The synthetic activity for DNA was reduced by 14%, 26%, 42%, 40%, and 40% in the RPS for the gossypol pretreatment of 3, 4, 6, 7, and 8 weeks, respectively.

The effects of gossypol on nuclear protein in rat testes. II. The synthesis of histones and testis-specific proteins after gossypol treatment

This communication is to report the effects of gossypol on the synthesis of chromosomal basic proteins in the spermiogenic cells. A double-labelling experiment has been performed. The control rats received 14C-arginine, whereas the gossypol-treated rats received a 3H-arginine injection. An equal volume of the tissues (from control and gossypol-treated) were combined, and the total nuclear basic proteins (TNBP) from round spermatids (RS) and elongating spermatids (ES) were extracted for electrophoretic separation. By studying the ratio of 3H/14C, it was indicated that the synthesis of H1, H3, H2B plus H2A and TP1 in the RS was reduced by gossypol. The amount of inhibition of these proteins were 48%, 19%, 27%, and 11%, respectively. In the ES, the synthesis of H1, H3, H2B plus H2A, H4 plus TP2, TP3, and TP1 was reduced by gossypol, the reduction was 33%, 22%, 26%, 14%, 33%, and 8%, respectively. The synthesis of S1 protein was not inhibited by gossypol in both RS and ES.

The effects of gossypol on nuclear protein in rat testes. I. Reduction in the content of basic proteins in the spermiogenic cells

In rat testes, after 45 days of gossypol treatment, the number of round spermatids (RS) reduced from 9.8 x 10(6) to 6.2 x 10(6) per testis. The number of elongating spermatids (ES) reduced from 6.4 x 10(6) to 3.1 x 10(6) per testis. Total nuclear basic proteins (TNBP, i.e., somatic type of histones H1, H2A,B, H3, and H4, plus testis-specific proteins TP1,2,3, and sperm-specific S1 proteins) were extracted from RS and ES. Gossypol has no detectable effect on the concentration of TNBP in RS. However, significant effect was found in ES, where TNBP was reduced from 8.7 micrograms to 6.8 micrograms/10(6) cells. A two-stage polyacrylamide gel has been used to separate the TNBP and the individual proteins were quantified by a Beckman Model DU-7 computer-monitored spectrophotometer. In the RS cells, the content of the TNBP was not sensitive to gossypol. However, in the ES cells, the content of histones H1, H2A, and H2B were reduced by gossypol treatment (with an inhibition of 50%, 58%, and 31%, respectively). The inhibition on H3, TP1, TP3 and S1 was insignificant by gossypol.

Quantification of müllerian inhibiting substance in developing chick gonads by a competitive enzyme-linked immunosorbent assay

An immunoblotting method was used to purify a Müllerian-inhibiting substance (MIS)-specific antiserum. The serum was used to quantify the content of MIS in developing chick gonads by competitive enzyme-linked immunosorbent assay. From embryonic stages to the eleventh week after hatching, male chicken testes have a high content of MIS in the following two stages: (1) from the sixth to the eighth day and from the fourteenth to the twentieth day of incubation, and (2) from the second to the eighth week after hatching. The high content of MIS in the early embryonic stage is closely correlated with the natural pattern of Müllerian duct regression observed in the male embryo. From the sixth to the twelfth day of incubation, the female right ovary contains a higher content of MIS than that of the left ovary. Up to the fourteenth day of incubation, the content of MIS in the left ovary reaches maximum levels and then declines. The combination of MIS from right and left ovaries was found to be highest in the ninth to the fourteenth day of incubation, when the regression of the right Müllerian duct reached its highest peak. However, the question of the inability of MIS to cause regression of the female left Müllerian duct and the caudal part of the right duct is raised and discussed. The hypothesis that prenatal estrogenic hormone (diethylstilbestrol) protects the Müllerian duct has been reevaluated. It was found that estrogen does not reduce the MIS content in prenatally treated gonads.

Purification of chicken testicular müllerian inhibiting substance by ion exchange and high-performance liquid chromatography

A highly purified protein molecule was obtained from the secretory proteins of 8-week-old chicken testes using ion-exchange column chromatographic procedures, including DEAE Bio-Gel A, CM Bio-Gel A, wheat germ lectin columns, and high-performance liquid chromatographic (hplc) separation techniques. This protein molecule has a molecular weight of 74,000 Da (74K protein). The isolated 74K protein induces regression of chicken Müllerian ducts grown in vitro. The 74K protein does not cause regression of cultured embryonic intestine or Wolffian duct. When the total testicular secretory proteins are resolved in a two-dimensional gel electrophoresis, approximately 120 polypeptides are obtained. The purified 74K protein has a pI of 6.1. Analysis of amino acid composition indicates that the 74K protein is relatively acidic in nature with a ratio of acidic to basic amino acids of 1.93.

Age- and function-related change in the quantity of high mobility group protein in chick oviduct

We describe the investigation of the content of chromosomal high-mobility group 1 (HMG1) protein in three cellular fractions (cytosol, microsomal, and nuclear) of the magnum and shell gland of young and aged hen oviducts. In the magnum of the aged hen oviduct, the amount of the HMG1 protein (microgram protein/mg DNA) in the three fractions was 9.3 +/- 1.1, 0.18 +/- 0.03, and 2.4 +/- 0.4, respectively. Whereas the values were 11 +/- 1.2, 0.27 +/- 0.08, and 4.2 +/- 0.4, respectively, for the young hen. 12, 50, and 43% less were found in the aged hen magnum. In the shell gland of the functionally active hen oviduct, the protein in the three cellular fractions was 8.6 +/- 1.05, 0.42 +/- 0.06, and 3.9 +/- 0.55, respectively. In the shell gland of the functionally inactive aged hen, the values were 8 +/- 1.05, 0.28 +/- 0.09, and 0.85 +/- 0.12, and in the inactive shell gland of the young hen, they were 7.6 +/- 1.0, 0.27 +/- 0.09, and 1.75 +/- 0.22, respectively. The most significant difference was in the nuclear fraction, where the HMG1 protein in the functional hen shell gland was 123-359% higher than that of the inactive ones.

Decreased ovalbumin-gene response to oestrogen in the prenatally diethylstilboestrol-exposed chick oviduct

Prenatal exposure of the female chick-embryo Müllerian duct to diethylstilboestrol (DES) decreases its future capacity for epithelial tubular-gland-cell differentiation and oviduct ovalbumin-gene expression. Chick Müllerian ducts after prenatal exposure to different concentrations of DES were tested after birth to determine the response of the oviduct toward the oestrogen induction. The quantity of DNA was biochemically determined, the differentiation of tubular-gland cells in the oviduct was studied by light microscopy, and the expression of the ovalbumin gene was detected by hybridization of the total RNA with radioactive ovalbumin cDNA. Comparisons among these three parameters revealed that the expression of the ovalbumin gene was affected most by DES exposure. Exposure to high doses of DES suppressed ovalbumin-gene expression by 75-78%, and inhibited tubular-gland-cell differentiation and thus decreased the DNA content by 29 and 32% respectively. Exposure to low doses of DES caused suppression of ovalbumin-gene expression by 47-53%, but it did not affect the other two parameters. Prenatal DES exposure has strong inhibitory effects on the Müllerian duct at the age (5-8-day-old embryos) when the organ is undifferentiated. Less inhibition is observed when the organ becomes differentiated (15-day-old embryos and older).

Changes in duration and amplitude of the evoked muscle action potential (EMAP) over distance in peroneal, median, and ulnar nerves

Standard nerve conduction techniques measure the conduction of the fastest conducting axons. Slower conducting axons determine the amplitude, duration, and configuration of the EMAP. Normal data showing the change in amplitude and duration of the evoked EMAP over a length of nerve segment as well as the change per centimeter of that nerve segment has been lacking. This study supplies this data for the peroneal, median and ulnar nerves (tables 2-5) and gives examples of clinical application of these techniques in the diagnosis of compression syndrome and peripheral neuropathies with demyelination. Emphasis is also placed on potential sources of error which may affect the results obtained using these techniques. Further study of the application of these techniques in the diagnosis of neuropathies is indicated.

Down-regulation of insulin receptors in postnecrotic cirrhosis of liver

Eighteen patients with postnecrotic cirrhosis of liver, including three patients who had had a portosystemic shunt operation, and 19 normal controls were studied. The tests performed included monocyte insulin receptor assay, iv glucose tolerance test, glucagon test, and insulin tolerance test. Insulin resistance was documented by the presence of fasting hyperglycemia and glucose intolerance together with hyperinsulinemia as well as resistance to exogenous insulin. The binding of [125I]insulin to monocyte insulin receptors was significantly decreased in cirrhotic patients compared with that in controls (P less than 0.02), and this was due to a significant decrease in the high affinity association constant (P less than 0.005). There was a significant negative correlation between the fasting insulin level and maximum [125I]insulin binding in cirrhotic patients (r = -0.8; P less than 0.02). Cirrhotics that had had a shunt operation showed a higher fasting insulin level, a greater insulin resistance, and a smaller maximum [125I]insulin binding to insulin receptors than those without shunt. All of these findings suggested a down-regulatory effect of hyperinsulinemia on the monocyte insulin receptors. An impaired glycemic response to glucagon was also found in cirrhotics, the exact mechanism of which remains to be elucidated. However, as the increases in plasma cAMP after glucagon were similar in cirrhotics and controls, the fault apparently did not lie in the glucagon receptor.

[Effects of gliclazide and glibenclamide on platelet function, fibrinolysis and metabolic control in diabetic patients with retinopathy (author's transl)]

In order to compare the metabolic and hemobiological properties of two sulfonylureas, thirty-five non-insulin-dependent diabetics were randomly assigned to two groups. Each group was given either gliclazide (n = 20) or glibenclamide (n = 15) for six months. Metabolic control was improved in both groups, as evidenced by the decrease in HbA1 concentrations. A significant fall in ADP (1 and 4 microM)--induced platelet aggregation was recorded in the gliclazide group, while antithrombin III levels remained normal throughout the trial and plasminogen activator levels increased. These hemobiologic changes may be effective in preventing the vascular complications of diabetes. In contrast, glibenclamide did not alter platelet aggregation. Furthermore, a significant decrease in both antithrombin III levels and basal and venostasis-stimulated plasminogen activator levels were seen in glibenclamide patients. The beneficial changes in hemostasis seen in gliclazide patients probably result from a direct effect of the drug since hemobiological parameters and metabolic control parameters were not correlated.

Detection of monoclonal antibody to high-mobility-group protein 17 from chick oviduct

Total chromosomal HMG (high-mobility-group) proteins have been isolated from oestrogen-stimulated chick oviduct. The antibodies against these proteins were induced in mice and subsequently their spleen cells were fused with myeloma cells to form hybridomas. A highly purified HMG protein, 17, was used to select for the hybridomas that produce antibody against HMG protein 17. The hybridomas were cultured and injected into mice to produce ascites. The antibody against HMG protein 17 in the IgG (immunoglobulin G) fraction of the ascites fluid was obtained by Protein A-Sepharose column chromatography. We have devised a solid-phase radioimmunoassay and enzyme-linked serological assay for the detection and characterization of this antibody directed against HMG protein 17. This anti-(HMG protein 17) IgG interacted only with HMG protein 17, but not with other chromosomal proteins, e.g. histone H1, "95K protein' (a chick oviduct-specific chromosomal protein) and HMG proteins 1, 2 and 14. The monospecific nature of this anti-(HMG protein 17) IgG fraction is confirmed.

Autoimmunity in ocular and generalised myasthenia gravis

Restricted ocular myasthenia gravis (OMG) and generalised myasthenia gravis (GMG) have been shown to differ in a number of respects. In OMG, antiacetylcholine receptor, antistriational and antinuclear antibodies were rare relative to their frequency in GMG. In contrast, antithyroid antibodies and a history of thyroid disease were much more prevalent in OMG than in GMG, OMG was not associated with the female predominance seen in GMG and appeared to be relatively common in some races rather than others. It is suggested that different pathogenetic mechanisms are responsible for these two forms of MG.

Thyrotrophin-binding inhibitory immunoglobulins and HLA-DRW3-two prognostic factors in Graves' disease

Thyrotrophin-binding inhibitory immuno-globulin (TBII) activity and HLA typing were performed in 38 Chinese patients with Graves' disease to find out the relationship among TBII activity, HLA antigen and relapse. Twelve out of 13 patients who were TBII-positive at anti-thyroid drug withdrawal relapsed. All seven patients with HLA-DR3 antigen relapsed, whereas all ten patients in remission did not have DR3. Therefore, both TBII activity at drug withdrawal and DR3 antigen could predict subsequent relapse. However, a larger patient sample is required to determine the precise relationship between TBII activity and HLA-DR3 antigen.

Changes in quantities of high-mobility-group protein 1 in oviduct cellular fractions after oestrogen stimulation

Antiserum against chick oviduct high-mobility-group protein 1 (HMG 1) has been induced in the rabbit. With this antiserum, immunobiochemical techniques have been used to probe the quantitative change of HMG 1 in the cellular fractions of chick oviduct before or after oestrogen stimulation. HMG 1 is detectable in the cytosol, microsomal and nuclear fraction of the chick oviduct cell. After administration of oestrogen to young chicks in vivo for 5 days, the quantity of HMG 1 is increased 4-fold in the cytosol, 3.5-fold in the microsomal fraction and 1.6-fold in the nuclear fraction. The finding of large amounts of HMG 1 in cytoplasm of oviduct cell is not likely due to its leakage from the nucleus. We anticipate that HMG 1 is synthesized in the cytoplasm and then transported into the nucleus. The synthesis and transportation of HMG proteins is probably regulated by oestrogen.

Incidence of hypothyroidism after radioactive iodine therapy for thyrotoxicosis in Hong Kong Chinese

The incidence of hypothyroidism in 1396 Chinese patients in Hong Kong treated for hyperthyroidism with 131I therapy is presented using the life-table method of analysis. One year after therapy only 6% of patients were hypothyroid, but the subsequent annual incidence was 3.5%, emphasising the need for life-time surveillance of these patients. A higher incidence of subsequent hypothyroidism was found in patients with diffuse surgical treatment, the total dose or number of doses of 131I, the severity of thyrotoxicosis and the age of the patient did not influence the rate of onset of hypothyroidism. The data suggest that in order to minimise the occurrence of hypothyroidism a lower dose of 131I per gram of thyroid mass should be used for patients with small diffuse glands.

An evaluation of supervoltage orbital irradiation for Graves' ophthalmopathy

Twenty patients with moderately severe ophthalmopathy due to Graves' disease or ophthalmic Graves' disease were treated by supervoltage orbital radiotherapy generated by a linear accelerator. Seven patients (35%) showed some response within 3 weeks of the treatment, four patients (20%) improved minimally while nine patients (45%) were unchanged. Improvement was noted mainly in soft tissue changes while proptosis decreased in only four patients. With one exception, ophthalmoplegia did not improve after the radiotherapy. The benefit obtained with the treatment was not impressive.

Thyroid-stimulating immunoglobulins in neonatal Graves's disease

Two patients with neonatal Graves's disease are reported. One of them had a delayed onset because of suppression of the fetal thyroid gland by antithyroid drug taken by the mother during pregnancy. Thyroid-stimulating immunoglobulins (TSAb), measured by a receptor assay, were present in both babies when they were thyrotoxic, and also in their mothers. TSAb were undetectable in both babies 1 year after birth. This strongly supports a pathogenetic role of TSAb in this condition through transplacental transfer of maternal TSAb.

A prospective study of the changes in thyrotropin binding inhibitory immunoglobulins in Graves' disease treated by subtotal thyroidectomy or radioactive iodine

The effects of subtotal thyroidectomy and radioactive iodine on thyroid-stimulating immunoglobulins, as measured by a receptor assay, more appropriately termed TSH binding inhibitory immunoglobulins (TBII), were studied in 74 patients with Graves' disease. Fourty-four patients received radioactive iodine therapy, while 30 were subjected to subtotal thyroidectomy. After radioactive iodine, more patients were TBII-positive (90.5% vs. 81.8%) than before treatment, and the mean TBII index decreased dramatically, the maximum decrease being at 3 months. The mean TBII index subsequently returned gradually to the pretreatment level. Subtotal thyroidectomy had a different effect on TBII activity. TBII indices were positive in 89.3% of these patients before any treatment but were positive in only 40% (12 patients) after antithyroid drugs had been given before surgery. After surgery, TBII indices remained positive in 7 patients, while the remaining 5 patients became TBII negative. Seventeen patients (56.7%) were TBII negative before operation and remained so after surgery. One patient who was TBII negative before operation became TBII positive 2 months after operation. Interestingly, postoperative relapse of hyperthyroidism occurred in 3 patients who were TBII positive, while hypothyroidism occurred in 7 patients who were TBII negative. Thus, the TBII activity after subtotal thyroidectomy might be an important factor in determining the outcome of surgery.

Studies on sex organ development. Effect of hormones on ornithine decarboxylase activity in the developing chick ovary

The response of ornithine decarboxylase activity to hormones in the embryonic left ovary was measured throughout the stages of development. During the early stage of ovarian development (9th day of incubation), the ornithine decarboxylase activity (in terms of pmol CO(2)/30min per mg of protein) was high (766); it decreased from the 10th to the 12th day (575-239), increased slightly from the 13th to the 15th day (306) and finally fell to a low value (192-20) from the 18th day of development to birth. Administration of an optimal dose of oestrogen to the 9-10-day embryo stimulated the ovarian ornithine decarboxylase activity by 48-53%. If the same dose of oestrogen was administered to the 15-18-day embryo, the ovarian enzyme activity was suppressed by 32-43%. This biphasic response to oestrogen for enzyme induction is characteristic of the developing ovary and is not observed in other genital organs of the chick. In the early developmental stage (9-10th day) testosterone has no effect on ovarian ornithine decarboxylase activity, but in the late stage testosterone inhibits the activity by 41%. Organ culture techniques have been used to test the ovarian response to lutropin (luteinizing hormone). Lutropin stimulated ornithine decarboxylase activity by approx. 99-155% in the ovary of the early embryonic stage (10-13th day), and by 175-200% in the ovary of the late embryonic stage (15-18th day). The alteration in enzyme activity in the ovary as assayed in vitro during development is not due to the effect of the size of the endogenous ornithine pool. The relationship of ornithine decarboxylase activity to the morphological and biochemical changes in the developing ovary is discussed.

Immuno-biochemical studies of a non-histone chromosomal protein in embryonic and mature chick oviduct

A non-histone chromosomal 95K protein (of mol.wt. 95 000) from hen oviduct was isolated and purified for antibody induction in the rabbit. Immuno-micro-complement-fixation and biochemical techniques were used to probe the presence of 95K protein in the oviduct chromatin of the embryonic and immature chick and the hen. The antiserum against 95K protein did not react with high-mobility-group proteins 1 and 2 obtained from oviduct, brain and liver, nor with histones. After limited digestion of chromatin with nucleases, until 10% DNA was hydrolysed, a small amount of 95K protein was released. Thus the 95K protein is probably not located in the region of chromatin that is sensitive to nuclease digestion. The amount of 95K protein in immature chick oviduct chromatin is less than that in the mature hen oviduct. However, the amount of 95K protein in the immature chick oviduct was increased after oestrogen administration. The presence of 95K protein in embryonic oviduct was detected in the 10-, 12-, 15- and 18- day chick embryo. The quantity of this protein increased with the age of the embryo and reached its highest value in the chromatin of the hen oviduct.

Changes in thyroid-stimulating antibody activity in Graves' disease treated with antithyroid drug and its relationship to relapse: a prospective study

Thyroid-stimulating antibodies (TSAb) were found in 51 patients (83.6%) with untreated Graves' disease. The mean TSAb index reached the normal level after 6 months of antithyroid drug therapy. In 9 patients (14.8%), TSAb remained persistently positive during and after antithyroid drug therapy, and relapse occurred in all. In 42 patients (68.8%), TSAb indices gradually returned to the normal range after drug treatment was started; in 38% of these, remission was maintained after treatment was stopped, in another 40.5%, relapse occurred when they were TSAb-positive, and the remaining 21.5% relapsed despite return of TSAb indices to the normal range. A positive TSAb index at the end of drug treatment was a useful indicator in predicting subsequent relapse because, with 1 exception, all patients who were still TSAb positive at drug withdrawal relapsed subsequently.