Venous malformations of the lower limb with severe localized intravascular coagulopathy treated with radiofrequency ablation and resection

Diffuse venous malformations (VMs) are relatively rare, especially the lesions locting special anatomical sites, and they are prone to casuse localized intravascular coagulopathy (LIC). Diffuse VMs can also cause bleeding and life-threatening disseminated intravascular coagulopathy (DIC) from trauma, surgery, and improper treatments. Thus, the treatment of diffuse VMs with LIC is quite tough. We report of a diffuse VMs with severe LIC that was treated with the combined use of minimally invasive treatment and open surgery.

The effect of vacancies on the optical properties of AuAl₂

AuAl2 is an intermetallic compound with a vivid purple colour attributable to a bulk plasmon energy in the visible part of the spectrum. However, the colour of as-deposited thin films is not as strong and only develops upon annealing. Density functional theory calculations of the dielectric function are presented for a variety of vacancy types and concentrations. The results support the view that the effect of annealing on colour is correlated with a reduction in concentration of Al vacancies. The effect of vacancies on the optical properties can be understood as arising from the complex interplay between interband transitions around the Fermi level and the plasmon energy.

Clinical observations in mesh suture treatment for infants of Kasabach-Merritt phenomenon

AIM

This study aims to evaluate the efficacy and adverse effects of the mesh suture treatment for infants of Kasabach-Merritt phenomenon and to report our treatment experience.

METHODS

Of the three patients, two of the cases occurred in the scalp and one occurred in the back of the chest, with platelet counts < 40 × 10⁹ /L before the treatment, reduced fibrinogen levels and increased D-dimer levels. All the three patients underwent the mesh suture treatment of the tumour area. Post-treatment observations were made regarding the surface colour and texture of the tumours, periodic routine blood examination results, fibrinogen and D-dimer levels.

RESULTS

After treatment, the degree of swelling on the tumour surface was reduced, surface tension was decreased, the tumour colour turned pale red from dark red and the skin gradually returned to normal. Two days after treatment, the platelet counts increased to 70 × 10⁹ /L or higher; the platelet count reached a normal level after 1 week in two cases. The fibrinogen level increased in varying degrees after treatment, whereas the D-dimer level was reduced. One case showed a small amount of exudate at the suture area, 1 month after the treatment; improvements were observed 3 days after changing the local dressing. All the patients were followed up for 6 months to 1 year, during which the patients showed complete regression of the lesion and relapse, normal platelet counts and normal fibrinogen and D-dimer levels.

CONCLUSIONS

We recommend the mesh suture treatment as the first treatment of choice for paediatric Kasabach-Merritt phenomenon.

[Clinical analysis for treatment of 1 080 cases of infantile hemangiomas with oral propranolol]

OBJECTIVE

To explore the indications of hemangiomas of different types by observing the clinical efficacy of oral propranolol.

METHODS

For this retrospective study from October 2009 to June 2013, a total of 1 080 cases were classified into 5 types according to their clinical characteristics. There were 338 males and 742 females. Their types were telangiectasis (n = 58), papular (n = 424), plump (n = 106), deep (n = 176) and mixed (n = 306). Propranolol was orally administered at a dose of 1.0 or 1.5 mg/kg daily (1.0 mg/kg for infants aged 2.5 months or under; 1.5 mg/kg for those aged 2.5 months or above). Dynamic observations of hemangioma size, texture or color change and adverse events during treatment were performed. Drug withdrawal was usually made after dosing for 1 year or under when there was a total regression of hemandiomas. The efficacy was evaluated on a 4-level scale.

RESULTS

Rank test results showed no significant differences between 5 types during the changes of lesions (χ² = 1.738, P > 0.05). Changing of lesions occurred 8.0 (3.7, 16.2) hours after dosing in telangiectasis type, whereas 6.5 (4.1, 14.3) hours in papular type, 7.0 (5.5, 12.7) hours in plump type, 7.5 (3.8, 11.3) hours in deep type and 6.5 (4.2, 13.4) hours in mixed type. After a follow-up of 6 months to 2.5 years, there were 378 grade IV case (35.00%), 574 grade III case (53.15%), 120 grade II cases (11.11%) and 8 grade I cases (0.74%). And there were significant differences between patients of different types (P < 0.05). Patients of deep type had the best grade IV curative effect rate of 59.09% (104/176) , then papular type of 51.25% (162/316) and telangiectasis type of 26.41% (112/424).

CONCLUSION

As a first-line treatment for hemangioma, propranolol shows excellent efficacies for patients of deep, mixed, plaque and papular types.

Expression of hepatoma-derived growth factor in early-stage cervical adenocarcinoma

16002

Background: Hepatoma-derived growth factor (HDGF) is a unique nuclear/growth factor and plays an important role in the progression of different types of cancer. The current study was designed to elucidate the role of HDGF expression during the development of. early-stage cervical adenocarcinoma. Methods: A total of 63 patients with early-stage cervical adenocarcinoma were enrolled in this retrospective study. The HDGF expression in cervical adenocarcinoma was determined by immunohistochemistry. The HDGF immunostaining in the nuclei and cytoplasm of clinical samples was scored and expressed as labeling index to correlate with the clinical parameters of patients with early-stage cervical adenocarcinoma using SPSS software. Results: HDGF immunostaining was detected in both cytoplasm and nucleus of cervical adenocarcinoma. Compared with adjacent non-tumor tissue samples, HDGF expression was significantly increased in either nuclear or cytoplasmic compartment in cervical adenocarcinoma samples (P < 0.001). Moreover, elevated nuclear HDGF levels were correlated with lymph-vascular space invasion (P < 0.05), lymph node metastasis (P < 0.001), recurrence (P < 0.001), advaced grade(P < 0.001). Conclusions: HDGF overexpression is involved in the carcinogenesis of cervical adenocarcinoma.

[Table: see text]

No significant financial relationships to disclose.

Induction of mononuclear cell infiltration into liver by Japanese herbal medicine

Juzen-Taiho-To (JTT) is a Japanese herbal medicine that has been administered mainly to patients weakened by long illness. Currently, it has also been used for cancer patients and showed antitumor effects that have been reported as phagocytosis enhancement, cytokine induction and antibody production. In this study, we examined the effect of oral administration of JTT in mice on the immunological restoration of the liver, especially focused on natural killer (NK) T-cell induction. Mice were grouped to receive JTT or placebo orally for a period of 1, 3 and 7 days. After sacrifice, the liver tissue was fixed, embedded and stained with hematoxylineosin and some antibodies by common staining methods. Transmission electron microscope (TEM) observation was also carried out. Although the JTT-treated mice had the same appearance as the non-JTT-treated mice, their livers were infiltrated by massive mononuclear cells, some of which were aggregated in clusters. Immunohistochemical staining revealed that there was abundant cytokine expression of interleukin (IL)-12 and massive infiltration of mononuclear cells with large granules in the liver of JTT-treated mice. Oral administration of JTT may induce the expression of IL-12 and be followed by immunological restoration such as NK T-cell induction in liver

Cronkhite-Canada syndrome: report of two cases

Two cases of Cronkhite-Canada syndrome are reported. In the first case, a 56-year-old woman had an adenoma of the colon, arising within the Cronkhite-Canada polyps, which was removed by endoscopic polypectomy. This suggests possible neoplastic transformation of polyps in this syndrome. She achieved remission with corticosteroids, but the polyposis recurred (only in the stomach) 7 months after the remission. In the recurrent polyposis, corticosteroid therapy resulted again in complete remission, which has lasted for 5 years. In the second case, a 69-year-old man developed typical manifestations of the syndrome while under emotional stress. He had a past history of chronic pityriasis lichenoides, and serum antinuclear antibody was positive. These findings suggested a possible role of autoimmune response in the pathogenesis of the syndrome. Corticosteroids were also effective in this patient.

Effects of olfactory bulbectomy on NMDA receptor density in the rat brain:

Olfactory bulbectomy (OBX) transects the glutamatergic efferents from the olfactory bulbs, and the changes of glutamatergic N-methyl-D-aspartate (NMDA) receptor-mediated function are though to be involved in the behavioral deficits seen in OBX rats. In the present study, irritability scores in OBX male Wistar rats were correlated with discrete regional effects on NMDA receptor function measured using a [3H] MK-801 binding assay. Irritability scores, measured before and for 2 weeks after OBX, showed a gradual increase in irritability after OBX. A reduction of the NMDA receptor density was observed in the cerebral cortex and amygdala 16 days after OBX, but not in the striatum, olfactory tubercle, entorhinal cortex, and hippocampus. These results demonstrate that OBX causes changes in the NMDA receptor system in certain brain regions and suggest that these changes may be responsible for the behavioral deficits of OBX rats.

Studies directed at the use of a parallel synthesis matrix to increase throughput in an in vivo assay

Heparin is the anticoagulant of choice for hospitalized patients, but it is dosed only by injection because it is not absorbed following oral administration. We have discovered and prepared compounds (delivery agents) that facilitate the gastrointestinal absorption of heparin in rats, monkeys, and humans when given orally. We are currently developing a parallel synthesis approach to increase our delivery agent screening throughput in vivo. This approach has been used to produce micromolar quantities of compounds for testing in rats in a 5 x 5 parallel synthesis array. Using an amine benzoylation reaction sequence, 10 mixtures were prepared. These mixtures contained equal weight quantities of five N-substituted, non-alpha, amino acid delivery agents. Each of these mixtures was orally administered to rats in combination with heparin, and plasma clotting times (APTT) were measured to determine activity. Deconvolution of the data accurately identified the most active individual components. Independent synthesis of these compounds verified their activity. This parallel synthesis approach is an effective tool for the screening of oral heparin delivery agents and has increased screening throughput significantly.

The devastating consequence of iodine deficiency

Endemic cretinism is the most striking consequence of iodine deficiency. Although cretinism is a serious condition, it usually involves only about 5% of the population even in serious endemic areas. There is a spectrum between cretinism and normality, many are able to perform simple work and look apparently normal, but it is difficult for them to perform skilled labor. Studies in China using the IQ distribution curve revealed that every person in an endemic area lost about 10-15 IQ points, so that the socio-economic development of the community was severely affected.

Synthesis and evaluation of compounds that facilitate the gastrointestinal absorption of heparin

A family of novel compounds (delivery agents) that promote the gastrointestinal absorption of USP heparin in rats and primates has been discovered. The delivery agents in combination with heparin were administered either orally or intracolonically in an aqueous propylene glycol solution and caused dramatic increases in both plasma heparin concentrations (anti-Factor Xa) and clotting times (APTT). Using one of the most effective delivery agents in this series, an estimated relative bioavailability of 8% can be achieved following oral administration to cynomolgus monkeys. To establish a correlation between the in vivo data and an in vitro parameter, immobilized artificial membrane (IAM) chromatography was performed. Log relative k' values were correlated to the efficiency of oral heparin delivery.

Dynamics of environmental supplementation of iodine: four years' experience of iodination of irrigation water in Hotien, Xinjiang, China

Hotien prefecture, Xinjiang Province, China, in the Taklamakan Desert, is an area of severe iodine deficiency. Because usual methods of iodine supplementation failed here, we began supplementation in 1992 with potassium iodate, which was added to irrigation water (Lancet 1994; 334:107-110). We report 4 y experience with this method in 3 townships that contained a total treated population of 37,000. Potassium iodate was dripped into irrigation water (to a concentration 10-80 microg/l) during a 2- to 4-wk period. During the 3 y that followed, no further supplementation was made, and iodine concentrations increased several fold in crops and plants, sheep and chicken thyroid glands, and meat and in urine of children 2-6 y of age and of women who were of childbearing age. Infant mortality decreased 50%, and sheep production increased 43%. Iodine repletion of soil through irrigation water is an effective and cost-efficient way of providing iodine in appropriate situations.

Haemodynamic comparison of sevoflurane and isoflurane anaesthesia in surgical patients

PURPOSE

To compare the haemodynamic responses to surgical incision during sevoflurane and isoflurane anaesthesia and to compare the haemodynamic effects of each anaesthetic alone with those obtained using an equipotent mixture of each anaesthetic plus N2O during steady-state surgical stimulation.

METHODS

Twenty-four patients undergoing gastrectomy were randomized to receive sevoflurane (n = 12) or isoflurane (n = 12). At 1.5 MAC, haemodynamic measurements were performed before and after surgical incision. During intestinal anastomosis, patients in each group were given (in random order) either 1.5 MAC of the designated anaesthetic or 0.85 MAC of the volatile plus 0.65 MAC N2O. Haemodynamic measurements were repeated under each condition.

RESULTS

One patient in the sevoflurane group and two in the isoflurane group were excluded from the incision study because of hypotension. In both groups, incision increased the heart rate (HR), mean arterial pressure, mean pulmonary arterial pressure (MPAP), pulmonary capillary wedge pressure (PCWP), cardiac index, and systemic vascular resistance index (SVRI). There were no intergroup differences in the effects of incision. Inclusion of N2O resulted in an increase of MPAP (P < 0.05) in both groups, an increase of central venous pressure and PCWP in the sevoflurane group (P < 0.005), and a decrease of HR (P < 0.005) and an increase of SVRI (P < 0.05) in the isoflurane group. There were no intergroup differences in the effects of N2O.

CONCLUSIONS

At 1.5 MAC, sevoflurane and isoflurane do not prevent the haemodynamic response to incision. The haemodynamic effects of each volatile anaesthetic with N2O are minimal compared with those of equi-MAC volatile alone.

[Studies on structure of light degradation products of (-)-(S)-10-(1-aminocyclopropyl)-9-fluoro-3-methyl-7-oxo-2,3-dihyd ro-7H- pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acid (T-3761) in aqueous solution and solid state]

The structures of light degradation products of (-)-(S)-10-(1-aminocyclopropyl)-9-fluoro-3-methyl-7-oxo-2,3-dih ydr o-7H- pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acid (T-3761) in aqueous solution and in the solid state were investigated. In aqueous solution, ten products were detected using HPLC and in the solid state, one main product was detected. All these light degradation products were isolated and their structures were elucidated. It was revealed that in almost all light degradation products only the 1-aminocyclopropyl side chain at the 10-position of T-3761 is changed to various structures by light oxidation. Surprisingly we found a unique light degradation product, in which carboxylic acid at the 6-position of T-3761 is changed to the hydroxy moiety.

Studies on cognitive enhancing agents. II. Antiamnestic and antihypoxic activities of 1-aryl-2-(2-aminoethoxy)ethanols

A series of 2-(2-aminoethoxy)-1-phenylethanols having a variety of N- and phenyl-substitution patterns as well as 5- and 6-membered heteroaryl counterparts of our prototype compound 1 (2-(2-dimethylaminoethoxy)-1-phenylethanol) have been prepared and evaluated for antiamnestic and antihypoxic activities. Compound 3b, the 3-methylphenyl analogue of 1, proved to be significantly more potent than 1 in reversing electroconvulsive shock-induced amnesia as well as CO2-induced learning-impairment in mice. It exhibited low acute toxicity in mice and afforded a greater brain/serum concentration ratio than 1 after oral administration to rats.

Studies on cognitive enhancing agents. I. Antiamnestic and antihypoxic activities of 2-dimethylaminoethyl ethers and related compounds

N-(2-Dimethylaminoethyl)carboxamide (1a-d), 2-dimethylaminoethyl alkyl ether (2a, b), and 2-dimethylaminoethyl 2-hydroxy-2-phenethyl ether (3a-c) and its amino and methylene analogues (3d, 4) have been screened for antiamnestic and antihypoxic activities in mice. A clear reversing effect on electroconvulsive shock-induced amnesia was found with 1a-d, 2a,b, and 2-dimethylaminoethyl 2-hydroxy-2-phenylethyl ether (3a). However, a protective effect against hypoxia was only observed with 3a. Compound 3a, which displayed the dual activity, was further investigated for ameliorating effect on CO2-induced memory impairment, and it was found to be more potent than indeloxazine and bifemelane. In addition, the acute toxicity of 3a in mice was significantly lower than that of tacrine, but its serum-to-brain penetration ability in rats was less than that of the reference drugs.

Studies on cognitive enhancing agents. III. Antiamnestic and antihypoxic activities of a series of 1-bicycloaryl-2-(omega-aminoalkoxy)ethanols

2-(2-Aminoethoxy)-1-hydroxyethyl derivatives of bicyclic arenes (naphthalene, thianaphthene, benzofuran, and indole) were prepared and screened for antiamnestic (AA) and antihypoxic (AH) activities which were evaluated by measuring the reversing potency in electroconvulsion-induced amnesia and the protective effect against hypoxia, respectively, in mice. Compound 3o, 1-(benzo[b]thiophen-5-yl)-2- (2-diethylaminoethoxy)ethanol, showed the best AA and AH activity profile, being superior to our prototype compound, 2-(2-dimethylaminoethoxy)-1-phenylethanol (1). Elongation of the ethylene linkage in the side chain of 3o to 3- and 4-carbon moieties brought about a significant decrease in AH activity. Compound 3o was further investigated for its protective effect against CO2-induced memory impairment and for acute toxicity in mice. It is ten-fold more potent than tacrine in the amnesia-reversal assay and is considerably less toxic than tacrine.

A sparse matrix screen to establish initial conditions for protein renaturation

Protein renaturation is of particular interest not only for the basic mechanisms of protein folding but also as a practical problem for proteins overexpressed in microorganisms, since recombinant proteins may accumulate as misfolded aggregates in "inclusion bodies" that are inactive after purification. We have established a systematic screening method to identify conditions which promote protein renaturation. A matrix of 50 different buffers, which were originally developed for protein crystallization, were found to facilitate the renaturation for eight of nine different proteins examined. The proteins tested include the adhesive protein bindin, recombinant bindin, and a variety of enzymes, including bacterial alkaline phophatase, horseradish peroxidase, lysozyme, trypsin, beta-galactosidase, rabbit carboxylesterase, and acetylcholinesterase. The total amount of activity recovered varied from 9 to 333% depending on the protein. The conditions that were found to promote renaturation are very different from the optimal conditions for enzyme activity. The finding that most of the proteins tested renatured to a significant extent in one or more of the buffers in the matrix suggests that the sparse matrix screen may be of general utility for establishing initial renaturation conditions for a wide variety of proteins. One initial renaturation conditions have been identified, the conditions may be optimized by systematically altering other parameters of the renaturation process.

[Determination of T-3761 in body fluids by high-performance liquid chromatography]

A high-performance liquid chromatographic procedure was developed for determination of T-3761 in human serum and urine. The method was based on column switching for serum, and direct injection for urine. The peaks were monitored by ultraviolet detection. The calibration curve was linear and quantitative in the concentration range of 0.01-30 micrograms/ml for serum and 0.5-900 micrograms/ml for urine. The intra-assay coefficient of variation was less than 7%. The intra-day and inter-day coefficient of variation were less than 4%.

[Study of metabolism of T-3761 in animal]

The metabolism of T-3761 in mouse, rat, rabbit, dog and monkey was studied. Four metabolites, other than unchanged T-3761, were detected and identified as follows: T-3761 glucuronide; T-3761M1, adduct of glucose; T-3761M2 and T-3761M3, compounds metabolized at 1-aminocyclopropyl ring. In urine of mouse, T-3761 glucuronide was mainly detected, but in urine of other animals, T-3761 was mainly detected.

Competitive binding radioassay for the determination of 5-fluorodeoxyuridine and 5-fluorodeoxyuridine-5'-monophosphate levels in plasma and tumor tissue

A competitive binding radioassay was developed to measure 5-fluoro-2'-deoxyuridine (FUDR) as well as 5-fluoro-2'-deoxyuridine monophosphate (FdUMP), FdUMP has been measured by a competitive binding radioassay with thymidylate synthase as the binding enzyme (TS assay). FUDR was enzymatically converted to FdUMP by thymidine kinase, and then the converted FdUMP was measured by the competitive binding assay to determine the concentration of FUDR in plasma and tumor tissue. As little as 100 pg/ml of FUDR or 50 pg/ml of FdUMP can be detected quantitatively by this method. When TS assay and high-performance liquid chromatography were compared for the measurement of FUDR and FdUMP levels in plasma and tumor tissue of Ehrlich carcinoma (EC)-bearing mice following administration of FUDR, a close agreement was observed for FUDR levels, though low FdUMP levels were detectable only by the TS assay method. The examination of intracellular metabolism of FUDR in EC cells by this method showed that metabolic conversion of FUDR into FdUMP or 5-fluorouracil is rapid. Thus, we have established a highly sensitive method for measuring not only FdUMP but also FUDR with TS assay. This should be very useful for experimental and clinical studies on fluoropyrimidines.

[Study on metabolism of pyridonecarboxylic acid II. Determination of metabolites of (+-)-7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)- 1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid p-toluenesulfonate hydrate (T-3262) in blood, urine, bile, and feces]

The fate of (+-)-7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl-1,4- dihyro-4-oxo-1,8-naphthyridine-3-carboxylic acid p-toluenesulfonate hydrate (T-3262) was studied using T-3262 and 14C-T-3262 in various animals. 1. Metabolites in serum and urine were assayed for mouse, rat, rabbit, dog and monkey following oral administration of T-3262. In serum, besides unchanged T-3262 base, T-3262A (N-acetylated) was detected in rat, rabbit and monkey; T-3262B (deamino-hydroxylated) was detected in monkey. In urine, unchanged T-3262 base was excreted mainly. But a few of metabolites (T-3262A, T-3262B, T-3262 glucuronide, T-3262A glucuronide, T-3262B glucuronide, and unknown compound M-1) were detected, and species difference existed in types of metabolites. 2. Metabolites in bile and feces were assayed for mouse and rat following oral administration of T-3262 and 14C-T-3262. Metabolites in bile were similar to the urine, but the volume of T-3262A and T-3262A glucuronide was larger than in urine. In feces, the excreted compounds mainly consisted of unchanged T-3262 base. 3. p-Toluenesulfonic acid, which is the counter acid for T-3262 base, was absorbed following the oral administration of T-3262, and excreted in urine in the unchanged form.

[Study on metabolism of pyridonecarboxylic acid. I. Isolation and identification of metabolites of (+-)-7-(3-amino-1-pyrrolidinyl)-6-fluoro-1- (2,4-difluorophenyl)-1,4-dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid p-toluenesulfonate hydrate (T-3262) in urine]

Metabolism of (+-)-7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4- dihydro-4- oxo-1,8-naphthyridine-3-carboxylic acid p-toluenesulfonate hydrate (T-3262) was studied. Metabolites were isolated from urine of mouse, rat, rabbit, dog and monkey following oral administration of T-3262, and identified using high performance liquid chromatography and mass spectrometry. Two metabolites, other than unchanged (+-)-7-(3-amino-1-pyrrolidinyl)-6-fluoro-1-(2,4-difluorophenyl)-1,4- dihydro-4-oxo-1,8-naphthyridine-3-carboxylic acid (T-3262 base), in which 3-aminopyrrolidinyl ring of T-3262 was metabolized, were identified as: (+-)-7-(3-acetyl-amino-1-pyrrolidinyl)-1-(2,4-difluorophenyl)-6-fluoro- 1,4- dihydro-4-oxo-1, 8-naphthyridine-3-carboxylic acid (T-3262A) in all animals: (+-)-1-(2,4-difluorophenyl)-6-fluoro-7-(3-hydroxy-1-pyrrolidinyl)-1,4- dihydro- 4-oxo-1,8-naphthyridine-3-carboxylic acid (T-3262B) in monkey. The glucuronide of T-3262 was detected in mouse, dog and monkey, the glucuronides of T-3262A and T-3262B were detected in monkey. M-I, unidentified metabolite, was detected only in mouse.

Perturbation of ribosome subunit interaction by glutaraldehyde fixation

Ultracentrifugal analysis of ribosomal purity is complicated by the rapid reequilibration of ribosomes with their subunits, and this is further enhanced by the effects of hydrostatic pressure. Fixation of the ribosome system prior to ultracentrifugal analysis supposedly freezes the reequilibration, and thus tends to obviate these difficulties. However, no redistribution of the ribosome-subunit population must be allowed to occur during fixation. Thus, it is necessary that fixation be extremely rapid compared to the ribosome-subunit reequilibration, in order to avoid errors in analysis. It was the purpose of this investigation to make a direct experimental comparison of the rates of these two processes, fixation and ribosome-subunit reequilibration, using the stopped-flow technique with a light-scattering detector, under a variety of buffer environment readjustments. The following findings resulted from this study: (1) Fixation in Tris buffers could not be followed by light scattering because of interaction of glutaraldehyde with Tris, leading to continuous production of high molecular weight contaminants. (2) Polymerization of glutaraldehyde leads to increased ultraviolet absorption, which must not be confused with scattering changes. (3) Undialyzed ribosome solutions prepared by dissolving stock suspensions stored at high levels of magnesium and univalent electrolyte into a known standard buffer produced solutions having free Mg2+ levels lower than those of original buffer, complicating kinetic observations and threatening ribosome stability. (4) Addition of malonic acid as a buffer for Mg2+ largely eliminated this problem. (5) The kinetics of glutaraldehyde were measured quantitatively by studying the perturbation of ribosome association and dissociation kinetics produced during shifts of Mg2+ levels. (6) At fixative levels not producing coagulation, fixation kinetics can be competitive with those of association-dissociation. (7) Mass action effects like those of dilution can be caused by fixation, and can give rise to excess subunits, which may be mistaken for loose couples in original ribosome preparations.

Pressure-jump kinetics of bovine beta-casein micellization

Two samples of highly purified bovine beta-casein supplied to us by Dr. T.A.J. Payens of the National Institute for Dairy Research, Ede, The Netherlands, were studied over a range of concentration from just below the critical micelle concentration (CMC) to 0.46%, in 0.2 ionic strength phosphate buffer (pH 7.0), at 20 and 25 degrees C. The relaxation process studied by pressure jump using a 90 degree scattered light detector was also confirmed by the temperature-jump method. In the pressure-jump experiments, the process could be separated into two general time domains, with an approximate ratio of 10-25:1, a behavior reminiscent of that found for synthetic micellar systems. The faster relaxation process was still exhibited below the CMC, however. The concentration dependence of the faster relaxation time agreed very satisfactorily with predictions from the micelle model described in the companion paper.

A micelle model for the sedimentation behavior of bovine beta-casein

The monomer-single polymer model of G.A. Gilbert (Disc. Faraday Soc. 20 (1955) 68) for moving boundary sedimentation has been used by Payens and colleagues to explain the observed results for bovine caseins, and by Harrington and colleagues to explain the observed results for myosin fibrils. Electron microscope pictures of Buchheim and Schmidt have subsequently revealed micellar beta-casein in the form of slightly elongated or spherical particles having a bimodal size distribution, but with a broad range of particle sizes, at concentrations not too far above the critical micelle concentration. The equilibrium properties of a broadly distributed micellar system can be fitted by the shell model developed by one of us, and in the present article, the shell model is extended to predict the moving boundary sedimentation behavior of such a system. The observed sedimentation patterns, as well as the critical concentration predictions of the monomer-single polymer Gilbert sedimentation model, are satisfactorily described with the present model, based on a continuous distribution of intermediates between monomers and the largest possible spherical micelles. For one example considered, the predicted frequency distribution of molecular weight is in qualitative agreement with the frequency distribution of particle volume found by Buchheim and Schmidt.

The quantitative determination of the paw-swelling activity of pertussis vaccine with special reference to its responsible toxic components

A method has been developed for quantitative determination of the early appearing mouse paw swelling activity of pertussis vaccine. Mice were inoculated with the vaccine into the left hind paws. The difference in the thicknesses between the inoculated and the uninoculated paws was taken as the swelling response in 16 hr after inoculation. It was transformed into logarithm as a response metameter. A linear log dose-log response regression line was obtained over a relatively wide range of doses of the vaccine. No deviation from parallelism was significant among the regression lines of different vaccines tested. The swelling activities relative to that of a reference vaccine of diphtheria-pertussis-tetanus combined (DPT) vaccines recently produced in Japan were determined. The relative activities ranged from 0.6 to 2.5, being twice the mean width of the 95% confidence interval of the relative activity. Further experiments showed that the activity significantly correlated with endotoxin and histamine-sensitizing factor (HSF) but not with lymphocytosis-promoting factor (LPF). In addition, the multiple regression analysis of such relationship suggested that the swelling activity is accounted for by the combined action of endotoxin and HSF. A model experiment with a mixture of the two toxins supported this conclusion.

In vitro and in vivo antibacterial activity of T-1982, a new semisynthetic cephamycin antibiotic

The activities of T-1982 (sodium 7 beta-[(2R, 3S)-2-(4-ethyl-2, 3-dioxo-1-piperazine-carboxamido)-3-hydroxybutanamido]-7 alpha-methoxy-3-[(1-methyl-1H-tetrazol-5-yl)thiomethyl]-3-cephem-4-carboxylate) against various gram-positive and gram-negative bacteria were compare with those of cefmetazole, cefoxitin, cefazolin, and cefoperazone. T-1982 was active against both gram-positive and gram-negative bacteria, including genera resistant to the other cephalosporins. T-1982 exhibited greater activity than did cefmetazole, cefoxitin, cefazolin, or cefoperazone against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, and Serratia marcescens and was also highly active against Bacteroides fragilis. T-1982 was as stable to various beta-lactamases as were cefmetazole and cefoxitin. The therapeutic activities of T-1982 in mice experimentally infected with various gram-negative bacteria were superior to those of cefmetazole, cefoxitin, cefazolin, and cefoperazone.

Conformation of the γ-Carboxyglutamic Acid-Rich Region of Prothrombin: Conformation-Specific Antibodies as Structural Probes

Stabilization of the tertiary structure of bovine prothrombin (PT) by Ca(II) has been evaluated immunochemically using conformation-specific antibodies directed against limited regions of the protein. Antisera raised against native PT or des-γ-carboxy PT (AbPT) were fractionated by sequential immunabsorption using affinity chromatography. Three antibody subpopulations, specific for different determinants on the protein, were isolated and evaluated using RIA: (1) Anti-(12-44), directed against the Gla-rich region 12-44, requires Ca(II) or other metals to interact strongly with PT. Anti-(12-44) cross-reacts poorly with AbPT, factor IX, factor X, and human PT; (2) Anti-PT-Ca(II) is specific for the binary PT-Ca(II) complex and does not interact with PT. Anti-PT-Ca(II) is directed against multiple antigenic determinants in the fragment 1 region; (3) Anti-AbPT is specific for AbPT and does not cross-react with PT. We conclude that occupancy of the high affinity metal binding site by metal ions is associated with a significant change in the conformation of the 12-44 region and other aspects of the N-terminal portion of PT. These antigenic surfaces are not present in AbPT. Conversely, some determinants on AbPT are not observed on PT. These results are consistent with our current model of the role of Gla in metal-dependent intramolecular and intermolecular bridging in the vitamin-K-dependent proteins.

Conformation of the γ-Carboxyglutamic Acid-Rich Region of Prothrombin: Conformation-Specific Antibodies as Structural Probes

Stabilization of the tertiary structure of bovine prothrombin (PT) by Ca(II) has been evaluated immunochemically using conformation-specific antibodies directed against limited regions of the protein. Antisera raised against native PT or des-γ-carboxyPT (AbPT) were fractionated by sequential immunabsorption using affinity chromatography. Three antibody subpopulations, specific for different determinants on the protein, were isolated and evaluated using RIA: (1) Anti-(12—44), directed against the Ola-rich region 12-44, requires Ca(II) or other metals to interact strongly with PT. Anti-(12-44) cross-reacts poorly with AbPT, factor IX, factor X, and human PT; (2) Anti-PT-Ca(II) is specific for the binary PT-Ca(II) complex and does not interact with PT. Anti-PT-Ca(II) is directed against multiple antigenic determinants in the fragment 1 region; (3) Anti-AbPT is specific for AbPT and does not cross-react with PT. We conclude that occupancy of the high affinity metal binding site by metal ions is associated with a significant change in the conformation of the 12-44 region and other aspects of the N-terminal portion of PT. These antigenic surfaces are not present in AbPT. Conversely, some determinants on AbPT are not observed on PT. These results are consistent with our current model of the role of Gla in metal-dependent intramolecular and intermolecular bridging in the vitarnin-K-dependent proteins.

Decreased hepatic nuclear L-triiodothyronine receptors in rats and mice bearing transplantable neoplasms

The concentration of hepatic nuclear T3 receptors was measured in isolated nuclei from athyreotic mice bearing thyrotrophic tumors and intact rats with Walker 256 carcinoma. Receptor concentration was reduced in all tumor-bearing animals. The mean receptor capacity of the Walker tumor-bearing rats [0.31 +/- 0.05 (SEM) ng/mg DNA] was significantly decreased from simultaneously assayed controls (0.47 +/- 0.04 ng/mg DNA; P less than 0.01). No change in the apparent equilibrium association constant was observed. In individual rats, the magnitude of the decrease in nuclear T3 receptor concentration was highly correlated with the decrease in tumor-free body weight. Additional studies showed that the decrease in nuclear receptors was not due to delayed equilibration of added T3 with nuclear sites in vitro or to an increase in endogenous hepatic T3 concentration. The plasma concentration of total and free T4 and T3 was decreased in tumor-bearing rats. Plasma TSH concentration, however, remained unchanged. Thus, these transplantable neoplasms seem to be associated with decreased hepatic nuclear receptors and low concentrations of plasma thyroid hormones. The unchanged plasma TSH suggests that the animals remained euthyroid.

Biochemical properties of a penicillinase from Escherichia coli carrying Rms 298

We obtained two R plasmids, i.e., Rms195 and Rms298, from a clinical isolate, E. coli GN5503. Penicillin beta-lactamase (PCase) was extracted from ML1410 Rms195+ and Rms298+, and was purified by chromatography. Rms195 PCase was identical to the type I PCase mediated by R-TEM, RI and Rms212. The isoelectric point of Rms298 PCase was 5.9 and its molecular weight was 21,000 +/- 1,000. The substrate profile and physiochemical properties indicate that Rms298 PCase belongs to the type IV PCase mediated by Rms139 isolated from Pseudomonas aeruginosa.