Reduced cardiac contractile responsiveness to isoproterenol in obese rabbits

Although obesity is characterized by increased sympathetic nervous system activity, there is often a paradoxical reduction in cardiovascular end-organ response to sympathetic stimulation. Mechanisms involved in reduced sympathetic responsiveness in obesity have not been well characterized. Therefore, we determined cardiac contractile responsiveness to beta-stimulation in the obese rabbit model using both isolated heart (IH) and isolated papillary muscle (IPM) preparations. Female New Zealand White rabbits were fed control (IH: n=9; IPM: n=6) or 10% fat diets (IH: n=9; IPM: n=7) for 12 weeks. Contractile responsiveness in the IH was determined using a modified Langendorff preparation to evaluate the dose-response relationship between isoproterenol and 1) peak developed pressure/g of left ventricular wet weight and 2) maximal rate of pressure development (+dP/dt/P). Contractile responsiveness in the IPM was determined using right ventricular papillary muscles to evaluate the dose-response relationship between isoproterenol and (1) peak developed tension (T)/mm2 cross-sectional area (CSA) and (2) maximal rate of tension development (dT/dt/CSA). In the IH, baseline and maximum developed pressure/g were reduced in obese rabbits by 37% and 31%, respectively (P< or =.05). In the IPM, baseline and maximum T/CSA responses were reduced in obese rabbits by 59% and 33%, respectively (P< or =.05). Potency of isoproterenol as reflected by the EC50 did not differ between lean and obese animals in either preparation. These results demonstrate that left ventricular contractility in obesity is reduced at baseline and in response to stimulation with isoproterenol and suggest that decreased responsiveness to beta-stimulation may be a factor in the obesity-related systolic dysfunction.

Gastrointestinal handling of [1-13C]palmitic acid in healthy controls and patients with cystic fibrosis

AIM

To examine the gastrointestinal handling of [1-13C]palmitic acid given as the free acid by measuring the excretion of 13C label in stool in 16 healthy children and 11 patients with cystic fibrosis on their habitual enzyme replacement treatment.

METHODS

After an overnight fast, each child ingested 10 mg/kg body weight [1-13C]palmitic acid with a standardised test meal of low natural 13C abundance. A stool sample was collected before the test and all stools were collected thereafter for a period of up to five days. The total enrichment of 13C in stool and the species bearing the 13C label was measured using isotope ratio mass spectrometry.

RESULTS

The proportion of administered 13C label excreted in stool was 24.0% (range 10.7-64.9%) in healthy children and only 4.4% (range 1.2-11.6%) in cystic fibrosis patients. The enrichment of 13C in stool was primarily restricted to the species consumed by the subjects (that is as palmitic acid).

CONCLUSIONS

There does not appear to be a specific defect in the absorption of [1-13C]palmitic acid in patients with cystic fibrosis. The reasons why cystic fibrosis patients appear to absorb more of this saturated fatty acid than healthy children is not clear and requires further investigation.

Educational programme for staff implementing a new renal replacement therapy

Haemofiltration is increasingly being considered as an alternative choice of treatment to conventional Haemodialysis for patients with Acute and Chronic Renal Failure. A leading company in renal replacement therapy offered the renal unit the challenge of being one of the first units in the United Kingdom to trial a new on-line Haemofiltration machine.

Stable-isotope method for determining the gastrointestinal handling of [1-13C]palmitic acid

The 13C enrichment in individual fatty acids extracted from human feces following the oral administration of [1-13C]palmitic acid has been determined using a novel approach based upon gas chromatography-isotope ratio mass spectrometry. The method was established and tested for precision and repeatability. Analytical precision was determined from 10 repeated injections of a sample containing 16:0 and 18:0 with levels of delta 13C abundance measured at -34.01 +/- 0.60 and -23.62 +/- 0.95 delta per mil (parts per thousand) (/1000), respectively (mean +/- SD). For the repeatability study, measurement of enrichment of the same mixture of unlabeled fatty acid methyl ester (FAME) standards (13:0, 14:0, 16:0, and 18:0) was found to have standard deviations (0.45, 0.56, 1.46 and 1.54/1000, respectively). When labeled [1-13C]palmitic acid was serially diluted with naturally enriched palmitic acid, a linear relationship was obtained to a dilution of 10% enriched compound (530/1000). FAME were prepared from two fecal samples from a normal healthy adult; the first, a baseline specimen, containing no added label and the second, followed a single oral dose of [1-13C]palmitic acid and was enriched. Enrichment in 13C was confined to the solvent-soluble fraction following lipid extraction, and was only identified with prior acidification. The enrichments were measured in triplicate, baseline sample -32.66 +/- 0.5/1000, enriched sample +268.61 +/- 8.0/1000. Enrichment was restricted to the labeled species consumed, 16:0. The methodology described here allows for the separation of compounds prior to the determination of enrichment and can be utilized to contribute to a more complete description of the gastrointestinal handling of labeled substrates than previously obtained.

Determination of the potent antiprotozoal compound atovaquone in plasma using liquid-liquid extraction followed by reversed-phase high-performance liquid chromatography with ultraviolet detection

A specific and robust method is presented for the determination of atovaquone in plasma. Atovaquone is a potent antiprotozoal compound for use in immunocompromised patients who are intolerant of conventional therapies. The method involves a liquid-liquid extraction of the compound into hexane modified with 2% (v/v) isoamyl alcohol. The processed extracts are analysed by reversed-phase high-performance liquid chromatography with ultraviolet detection at 254 nm. The assay has a limit of quantification of 0.1 microgram/ml and is linear between 0.1 and 50 micrograms/ml. The method has been applied to many clinical studies and has been demonstrated to be precise and accurate with high sample throughput. Atovaquone is not significantly metabolised in humans.

Sedimentation analyses of the salt- and divalent metal ion-induced oligomerization of nucleolar protein B23

Protein B23 is a major nonribosomal nucleolar protein and putative ribosome assembly factor that has been demonstrated to form oligomers. Sedimentation velocity and equilibrium analyses were used to examine the oligomerization properties of recombinant proteins B23.1 and B23.2. Under low ionic strength conditions protein B23.1 was predominantly a 2.1S monomer with small amounts of a 7.1S oligomer. At NaCl concentrations of 0.1 M and above the protein was almost exclusively the 7.1S oligomer. The oligomer remained the predominant species in NaCl concentrations as high as 1 M, suggesting that oligomers are not stabilized by electrostatic interactions. Low concentrations of divalent metal ions (0.1 - 1mM Ca2+ or Mg2+) also promoted oligomerization. Reducing agents had no effect on oligomerization, indicating that disulfide bridges are not important in oligomer formation. Protein B23.2, the carboxyl-terminal truncated isoform, had sedimentation characteristics similar to that of protein B23.1, suggesting that the carboxyl-terminal end of protein B23.1 is not essential for oligomerization. Protein B23.1 was previously shown to bind nucleic acids [Wang, D., Baumann, A., Szebeni, A., & Olson, M. O. J.(1995) J. Biol. Chem. 269, 30994-30998]. The effect of protein B23.1 oligomerization on its interaction with a 230 base pair DNA fragment was examined by sedimentation analyses. Under conditions where significant amounts of monomer were present, protein B23.1 was capable of binding DNA, whereas conditions that strongly favored oligomerization caused a nearly complete abolition of DNA binding activity. These studies suggest that protein B23 exists in an equilibrium between monomer and oligomer and that the quaternary structure of the protein may regulate its DNA binding properties.

Isolation of serotype 1 Marek's disease viruses from vaccinated Australian flocks

Field samples were received for Marek's disease virus (MDV) isolation from clinically affected flocks from several regions of Eastern Australia. Lymphocytes were fractionated in Ficoll-Paque and passaged once or twice in chicken embryo kidney cultures. Serotype-specific virus was detected in infected cultures by indirect immunofluorescence with monoclonal antibodies. Serotype 1 MDV was isolated from 10 flocks. In samples from 5 of these flocks, serotype 2 and 3 vaccine viruses were isolated from the same specimen. In a parallel study, plasmas obtained during lymphocyte isolation were tested for antibodies to MDVs by agar gel precipitin (AGP) tests using serotype 1 and 3 antigen extracts. No correlation was observed between the rate of virus isolation and AGP positivity. The AGP test was incapable of discriminating between the different MDV serotypes.

Practical evolution and application of direct intracytoplasmic sperm injection for male factor and idiopathic fertilization failure infertilities

OBJECTIVE

To analyze the introduction of a new assisted fertilization technique for the treatment of severe male factor and idiopathic fertilization failure infertilities.

DESIGN

Retrospective analysis of 16-month clinical application of IVF-ET where insemination was performed solely by direct intracytoplasmic sperm injection.

SETTING

Clinical IVF-ET program.

PATIENTS

Ninety-two couples undergoing 105 cycles of sperm injection.

RESULTS

One hundred embryo transfers yielded 28 viable pregnancies (28%) from which eight normal deliveries have occurred to date. Complete cleavage arrest or fertilization failure occurred in four cycles, and one couple had all embryos cryopreserved. One thousand one hundred forty-three eggs were injected of which 173 (15%) degenerated. Four hundred seventy-nine of the surviving 970 eggs became normally fertilized (49%), and 381 of these zygotes (79.5%) developed suitably for cryopreservation or for transfer. Thirty-four of 310 embryos transferred implanted, yielding an implantation rate of 11%. Both testicular and epididymal sperm were used successfully to achieve fertilization and pregnancies, as was sperm retrieved by electroejaculation. Older women and couples suffering from prior idiopathic fertilization failure had a markedly poorer outcome.

CONCLUSIONS

These results confirm that the intracytoplasmic sperm injection technique is a successful form of assisted fertilization that can be applied to a wide range of couples at significant risk from fertilization failure.

Factors affecting success with intracytoplasmic sperm injection

In this study, 141 couples underwent 163 cycles of in vitro fertilization (IVF) and embryo transfer in which the eggs were inseminated by intracytoplasmic sperm injection (ICSI). Overall, 41% of the injected eggs were normally fertilized and 81% of the resulting embryos were suitable for cryopreservation (91 embryos) or uterine transfer. From 153 fresh embryo transfers, 45 ongoing or delivered pregnancies (27.6% per cycle) were achieved, and of the 507 embryos transferred, 54 successfully implanted giving an implantation rate per embryo of 10.7%. Five additional pregnancies did not yield a viable fetus or underwent a spontaneous abortion, giving a miscarriage rate of 10% (5/50). Increased maternal age or a prior diagnosis of failed fertilization after conventional IVF had a significantly negative impact on success. Sperm from the testis and epididymis, those retrieved by electro-ejaculation, and completely immotile ejaculated sperm all gave rise to pregnancies. ICSI reinsemination was used with limited success to rescue failed fertilization cycles, although the implantation rate per embryo was poor (5%). ICSI has greatly improved the ability to use IVF for treating couples with a poor fertilization potential.

Identification of urinary and biliary conjugated metabolites of the neuromuscular blocker 51W89 by liquid chromatography/mass spectrometry

Cisatracurium, (1R, 1'R, 2R, 2'R)-2,2-[1,5-pentanediylbis-[oxy(3-oxo- 3,1-propanediyl]]bis[1-[(3,4-dimethoxyphenyl)-methyl]-1,2,3,4- tetrahydro-6,7-dimethoxy-2-methylisoquinolinium] dibenzenesulphonate (51W89), is an intermediate-acting neuromuscular blocking agent. 51W89 is one of ten isomers contained in Tracrium (atracurium besylate) and represents approximately 15 percent of the atracurium mixture. Clinical studies have indicated that 51W89 is more potent and is significantly weaker as a histamine releaser than atracurium. In vitro studies in human plasma have shown that, like atracurium, 51W89 spontaneously degrades at physiological pH by Hoffmann elimination to form laudanosine and the quaternary monoacrylate. Subsequent ester hydrolysis of the monoacrylate generates the monoquaternary alcohol. In rat plasma, 51W89 is also metabolized by non-specific carboxylesterases to the monoquaternary alcohol and the monoquaternary acid, the former being rapidly hydrolysed further to the more stable acid. It has been reported that laudanosine can be further metabolized via N-dimethylation to yield tetrahydropapaverine. The rate-limiting step in the degradation of 51W89 in human plasma is Hofmann elimination, whilst in rat plasma, the action of non-specific carboxylesterases is rate limiting. As part of the development of 51W89, the disposition of 14C-51W89 following a single intravenous bolus dose was studied in various animal species and humans. In the present work, we describe the identification of 51W89 metabolites in urine and bile from these studies by high performance liquid chromatography/mass spectrometry using pneumatically-assisted electrospray ionization coupled to an on-line radioactivity monitor.(ABSTRACT TRUNCATED AT 250 WORDS)

Ten different dietary fibers have significantly different effects on serum and liver lipids of cholesterol-fed rats

The comparative effects of 10 different dietary fibers on serum and liver lipids were investigated by feeding male Sprague-Dawley rats diets containing 10 g cholesterol + 2 g cholic acid/kg diet, with 60 g fiber/kg diet. Diets were fed for 3 wk; cellulose was the control fiber. Rats fed psyllium (rich in soluble fiber) had the lowest serum and liver cholesterol concentrations. Rats fed other soluble fiber-rich fibers (oat gum, guar gum and pectin) also had significantly lower serum and liver cholesterol concentrations than rats fed cellulose. Although feeding diets containing both soluble and insoluble fibers (soybean fiber and oat bran) did not significantly alter serum cholesterol, liver cholesterol values were significantly lower than those of cellulose-fed rats. Rats fed rice bran, predominantly an insoluble fiber source, had significantly higher liver cholesterol and significantly lower body weight gains and serum triglyceride concentrations than cellulose-fed rats. Values for serum and liver cholesterol were similar for rats were fed insoluble-rich fibers (corn bran, cellulose and wheat bran). These observations indicate that feeding dietary fibers rich in soluble fiber produces lower serum and liver cholesterol concentrations than does feeding commonly available sources of water-insoluble fiber.

Patterns of survival in patients with Hodgkin's disease: long follow up in a single centre

BACKGROUND

Prolonged remission can now be induced in the majority of patients with Hodgkin's disease with chemotherapy and/or irradiation. However, there is a significant proportion of patients in whom this approach fails, either at presentation or subsequently. Survival is the definitive endpoint to assess treatment efficacy. In this study, the survival patterns of a large group of consecutive patients treated in a single institution are presented.

RESULTS

The overall median survival was 18.3 years. Clinical remission (complete remission plus good partial remission) was induced in 443 (85%); the median survival of patients in remission has not been reached. Fifty-eight patients achieved responses less than clinical remission with initial therapy (partial response) or had progressive disease, the median survival of this group being 1.4 years. With further therapy, remission was subsequently induced in 10; 5 are still alive, 5 have died between 1.9 years and 14.3 years. Twenty patients died before completion of therapy. Recurrence has been documented in 147 of the patients in remission (following initial therapy) over a median follow up period of 13 years (minimum 5 years). One hundred forty-three of these patients were retreated following recurrence (105 chemotherapy, 28 radiotherapy, 6 combined modality treatment and 4 surgery). Second remission was induced in 109/143 (76%). There was a trend towards better second remission induction in patients whose first remission was longer than 1 year (p = 0.06). The median duration of second remission was inferior to first remission duration (p < 0.001). There was no correlation between duration of first remission and survival following recurrence (p = 0.8) or with duration of second remission (p = 0.54). There was no significant difference in duration of second remission between patients who were initially treated with radiotherapy or chemotherapy (p = 0.3). The median survival following second remission was 12.0 years, being the same for patients with initially localized disease (stages I and II) treated with radiation alone and for patients with advanced Hodgkin's disease (stages III and IV) treated with chemotherapy. Survival after recurrence is significantly better for patients under 50 years at the time of recurrence (p < 0.001). Second recurrence was documented in 46 patients, third remission being reinduced in 22, the median survival of the latter being 5.1 years.

CONCLUSION

These results illustrate the importance of prolonged follow up in defining the clinical course of patients with HD and are vital for planning experimental chemotherapy at the time of treatment failure or recurrence.

Megavoltage pituitary irradiation in the management of prolactinomas: long-term follow-up

OBJECTIVE To determine the long-term effects of external beam megavoltage radiotherapy (RT: 4500 cGy via three portals at 180 cGy or less total daily dose) on endocrine function in prolactinomas. DESIGN Longitudinal study following radiotherapy with periodic re-assessment at regular intervals, at least 2 months off dopamine agonist therapy. PATIENTS Thirty-six female patients, age range 19-50 years, with either macroprolactinomas (12 patients) or microprolactinomas (24 patients), but without significant suprasellar extensions. MEASUREMENTS Clinical appraisal, and anterior and posterior pituitary assessment: basal levels at yearly intervals or less, with dynamic screening with TRH, LHRH and hypoglycaemic stimulation every 2-3 years. RESULTS Before RT, serum prolactin (PRL) levels ranged from 1150 to 34,000 mU/l; after RT (mean 8.5 years, range 3-14), serum PRL fell to normal (i.e. less than 360 mU/l) in 18 of the 36 patients (50%), and to just above the normal range (378-780 mU/l) in a further 10 (28%). Two patients had PRL levels at their last follow-up higher than those at presentation, with one patient showing evidence of tumour recurrence on CT scan. A total of eight of the 36 patients (23%) developed post-RT gonadal deficiency by the end of follow-up at 8 +/- 3.1 years (+/- SD, range 3-11), but six were aged over 40 years at that time. GH deficiency was frequent, occurring in 94% of patients, usually from 2 to 3 years post-RT, while TSH deficiency and reduced ACTH reserve was uncommon (each 14%), and occurred later. In the subgroup of 12 patients with macroprolactinomas, results were broadly comparable. CONCLUSIONS Megavoltage RT produces a progressive fall in serum prolactin in the great majority of patients with prolactinomas, with a relatively low incidence of TSH or ACTH deficiency. As it is now clear that dopamine agonist therapy alone provides sufficient management for microprolactinomas, RT may be used for the long-term control of macroprolactinomas, together with interim dopamine agonist therapy. It allows pregnancy to be safely undertaken but, in view of the delayed onset of gonadal deficiency, its administration should be timed with respect to the desired onset of conception in women.

Three-peaked chemiluminescent response of human peripheral blood leukocytes following stimulation with phytohaemagglutinin (PHA)

Luminol-enhanced chemiluminescence (CL) was used to examine the response of various leukocyte populations following stimulation with a crude extract of Phaseolus vulgaris, namely phytohaemagglutinin (PHA-C). Populations stimulated included a human peripheral mixed leukocyte preparation (MLP), and purified preparations of lymphocytes, monocytes and polymorphonuclear leukocytes (PMNL). Mouse peritoneal exudate cells and the lymphocytic cells lines Molt #4 and Daudi were also stimulated. Following stimulation, a characteristic three-peaked chemiluminescent response was obtained from the MLP population. Little or no response was obtained from the purified lymphocytes. Monocytes produced a sharp peak corresponding to the second peak of the MLP response and PMNL produced a broad peak corresponding to the third peak of the MLP response. Mouse peritoneal exudate cells containing lymphocytes and monocytes/macrophages showed a two-peaked stimulation which corresponded to the first two peaks of the MLP response. Molt #4 and Daudi showed no chemiluminescence if stimulated individually, but if added to a MLP substantial enhancement of the first and second peaks was observed. These results indicate some form of lymphocyte/monocyte interaction leading to enhanced CL following PHA-C stimulation.

Pharmacokinetics of intravenous amoxycillin and potassium clavulanate in seriously ill children

The pharmacokinetics of amoxycillin and potassium clavulanate were studied in 15 sick children after a 30 min iv infusion of 50 mg/kg amoxycillin and 5 mg/kg clavulanic acid as the potassium salt. Levels of both compounds in plasma were assayed microbiologically. Mean peak concentrations at the end of the infusion were 121.0 mg/l of amoxycillin and 12.0 mg/l of clavulanate, falling to a mean of 15.8 and 1.92 mg/l respectively after 2 h. Mean beta phase T 1/2 was 0.88 h for amoxycillin and 0.79 h for clavulanate. The elimination half-life of clavulanate in some individuals was much shorter because of higher plasma clearance. The data suggest that the treatment of some infections due to beta-lactamase producing organisms in such severely ill children may require more frequent iv administration of amoxycillin and potassium clavulanate, than in less severely affected children.

Long-term effects of radiotherapy for acromegaly on circulating prolactin

In 61 acromegalic patients, serum PRL was assessed (off medical treatment) before and 2 to 12 (mean 6.4) years after external beam radiotherapy. Before radiotherapy elevated PRL levels were present in 22 of 35 males (63%) and 12 of 26 females (46%) and were above 1000 mU/l in 11 males and 5 females. When studied for up to 5 years after radiotherapy, 22 of 23 (96%) patients who had not had surgery and who had normal PRL pre-radiotherapy showed an increased PRL level and this was also seen in 17 of 27 (63%) who had been hyperprolactinaemic initially. In contrast, 10 of 27 patients (37%) who had elevated pre-radiotherapy levels (all greater than 1000 mU/l) had a reduction in PRL values after radiotherapy. In all 11 patients who underwent surgery before radiotherapy, an increase in PRL was seen after radiotherapy. In the 21 patients followed for 10-12 years, the peak PRL value occurred 1-6 years after radiotherapy. After this, a progressive reduction of PRL to normal was seen. Normal levels were reached 4 to 10 years after radiotherapy. No correlation was found between pretreatment PRL values and final GH values in the whole group, nor between changes in PRL and the development of impaired ACTH or TSH secretion. Thus, different patterns of PRL behaviour suggest that radiotherapy treatment may either produce hyperprolactinemia from mild hypothalamic damage or ablate PRL secreting cells if they were present in the tumour before treatment. These changes do not predict final GH results or the development of hypopituitarism after radiotherapy.

Megavoltage pituitary irradiation in the management of Cushing's disease and Nelson's syndrome: long-term follow-up

We report the long-term follow-up of the clinical and biochemical effects of megavoltage pituitary irradiation (radiotherapy; RT), administered as primary or secondary therapy, for pituitary Cushing's disease and Nelson's syndrome in 52 patients. Irradiation was administered, from a 4-15 MeV linear accelerator, via a three-field technique (two lateral, one frontal), to a total dose of 4500 cGy (rad) in 25 fractions over 35 days. Twenty-one patients received RT as primary ablative therapy for Cushing's disease and were under follow-up 5.8 to 15.5 years later (median 9.5 years). All were initially treated with metyrapone to induce normal mean plasma cortisol levels, and all achieved clinical remission on this therapy. At latest follow-up, 12 (57%) are off all therapy, in clinical remission, with a normal mean cortisol through the day; however, only two show completely normal plasma cortisol responses to dynamic testing; four remain on medical therapy with metyrapone or op'DDD and all have required a steady dose reduction accompanied by falling plasma ACTH levels; five have required alternative therapy with bilateral adrenalectomy and/or transsphenoidal hypophysectomy. Fifteen patients received RT for Nelson's syndrome, developing after bilateral adrenalectomy, and have been followed up for 1.5 to 17.3 years (median 9.6 years). Fourteen patients showed progressive depigmentation, shrinkage of the pituitary adenoma and fall in plasma ACTH levels to 1-72% (median 16%) of the pre-RT basal value. In the remaining patient an initial fall in plasma ACTH was followed by tumour enlargement at 6 years, leading to death at 11 years after RT. Of the remaining patients, results are assessed in nine who received RT after unsuccessful transsphenoidal surgery, three after transfrontal surgery for aggressive macroadenomas, and four prophylactically after bilateral adrenalectomy. Radiotherapy remains a valuable second-line therapy for Cushing's disease and its complications.

Durability of immunity to diphtheria, tetanus and poliomyelitis after a three dose immunization schedule completed in the first eight months of life

Blood samples were obtained from school entrants whose primary immunization schedule had consisted of three doses of DT or DTP vaccine and three doses of OPV all given before the age of 8 months. The sera were separated and assayed for diphtheria antitoxin, tetanus antitoxin and antibodies to the three serotypes of poliovirus. The results of the assays showed that the abbreviated three dose schedule induced satisfactory immunity to all five infections until school entry and that a reinforcing dose at 18 months was unnecessary.

Specificity of limited range of motion variable resistance training

The present study evaluated the effect of limited range of motion (ROM) variable resistance training on full ROM strength development. Twenty-eight men and 31 women were randomly assigned to one of the three training groups (A, B, AB) or a control group (C). A, B, and AB performed variable resistance bilateral knee extension exercise 2 (N = 25) or 3 (N = 19) d.wk-1 for 10 wk with an amount of weight that allowed one set of 7-10 repetitions. Group A trained in a ROM limited to 120 degrees to 60 degrees of knee flexion. Group B trained in a ROM limited to 60 degrees to 0 degrees of knee flexion. Group AB trained full ROM. Prior to and immediately following training, isometric knee extension strength was evaluated at 9 degrees, 20 degrees, 35 degrees, 50 degrees, 65 degrees, 80 degrees, 95 degrees, and 110 degrees of knee flexion with a Nautilus knee extension tensiometer. Reliability coefficients for repeated measurements of isometric strength at multiple joint angles were high (r = 0.86-0.95, P less than 0.01; SEE = 23.1-37.2 N.m). Compared to the control group, all training groups improved in isometric strength (P less than 0.01 at each angle tested except for group A at 9 degrees and 20 degrees of knee flexion and group B at 95 degrees of flexion. Isometric strength gains for group AB were similar throughout the full ROM. Isometric strength gains for the limited ROM trained groups were greater in the trained ROM than in the untrained ROM (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Longer-term regulation of pyruvate dehydrogenase kinase in cultured rat hepatocytes

The activities of pyruvate dehydrogenase (PDH) kinase and of PDH kinase activator protein (KAP) were increased 2-2.4-fold during 25 h of culture of hepatocytes from fed rats with glucagon plus n-octanoate. PDH kinase activity in hepatocytes from starved rats (initially 2.2 x fed control) fell during 25 h of culture in medium 199 (to 1.5 x fed control), but was maintained by glucagon plus octanoate. Dibutyryl or 8-bromo cyclic AMP increased PDH kinase activity 2-2.2-fold in hepatocytes from fed rats, but phenylephrine and isoproterenol (isoprenaline) were without effect. Insulin blocked the action of glucagon to increase PDH kinase activity and decreased the effect of octanoate and octanoate plus glucagon. It is suggested that the effects of starvation to increase activities of PDH kinase and of KAP in liver are mediated by alterations in circulating concentrations of glucagon, fatty acids and insulin and in hepatic cyclic AMP.

Management of localized non-Hodgkin's lymphoma: the experience at St. Bartholomew's Hospital 1972-1985

A retrospective study of 202 patients with clinical stage I and II non-Hodgkin's lymphoma managed at St. Bartholomew's Hospital between 1972 and 1985 was conducted. Patients were treated either with radiotherapy alone, radiotherapy and adjuvant chemotherapy, or chemotherapy (with or without adjuvant radiotherapy). At the onset of the study it was intended that all patients with localized NHL should be treated with involved field radiotherapy and adjuvant 'CVP'. As it became apparent that this was inadequate for some patients and too toxic for others a flexible approach was later adopted. Treatment selection depended on age, volume, distribution of disease and histological subtype. The actuarial 5 year overall survival for the whole group was 70 per cent. Death from lymphoma after 5 years was very rare. Increasing age and high grade histology were highly significant adverse prognostic factors by multivariate analysis. The results for patients with high grade and low grade histology were therefore analysed separately, as was the outcome for patients presenting with either gastrointestinal or skin lymphomas. During the latter part of the study period intensive chemotherapy was given as the initial treatment to patients with high grade histology and bulky, or stage II disease. Twenty out of 24 patients so treated achieved complete remission and only one has relapsed to date. These results are encouraging and probably explain the absence of a difference in prognosis between patients with stage I and IE disease and those with stage II and IIE disease observed over the whole period of the study. Remission was achieved in the overwhelming majority of patients with low grade histology for whom radiotherapy was selected as primary therapy. Duration of remission was better in patients who received adjuvant chemotherapy than in those treated with radiation alone, but no difference in overall survival was observed between these groups. Neither stage nor the presence of a follicular histological pattern correlated with prolonged survival in patients with low grade histology.

Insulin reverses effects of starvation on the activity of pyruvate dehydrogenase kinase in cultured hepatocytes

In tissue culture of hepatocytes, insulin (0.1-1 munits/ml for 4 h) reversed completely the effects of starvation of rats to decrease the activity of pyruvate dehydrogenase (PDH) complex and to increase the activities of PDH kinase and PDH kinase activator protein. It had no effect in hepatocytes from fed rats. Significant effects of insulin were detected with 0.01 munit/ml after 4 h, and in 1-2 h with 1 munit/ml.

Follicular lymphoma: prognostic factors for response and survival

One hundred forty-eight patients with newly diagnosed follicular lymphoma were treated over a 12-year period. Twenty-two patients received radiotherapy for stage I and II disease, followed by adjuvant chemotherapy in 14 patients. One hundred thirteen were treated at presentation with short courses of chemotherapy, most often with single-agent chlorambucil for bulky stage II and stages III and IV disease. Thirteen patients were managed expectantly until there was evidence of disease progression. The median survival was 9 years. Patients treated with radiotherapy for stage I and II disease had an 83% relapse-free survival, but those with bulky stage II or stages III and IV disease treated with chemotherapy pursued a remitting and relapsing course with a 70% response rate at initial and subsequent retreatments, but a median duration of remission of 4 years in stage III and 1 year in stage IV disease (P = .041). Patients were observed in relapse and retreatment was administered as appropriate, once every 33 months on average. Poor prognosis patients could be identified by a combination of the presentation characteristics: B symptoms, hepatosplenomegaly, anemia, and abnormal liver function. These factors predicted a poor response to treatment and correlated with a short survival. Histologic subgroups were not associated with differences in survival, but transformation to a diffuse high-grade lymphoma was observed in 23 of the 72 patients (32%) at risk, with a median follow-up of 6 years and 6 months, and was associated with a very poor prognosis. The present treatment strategy has proved successful for most patients with localized disease and those older patients with indolent small volume disseminated follicular lymphoma. New approaches are being investigated for the younger poor prognosis patients.

A new 111In-bleomycin complex for combined radiotherapy and chemotherapy

Six days after tumor transplantation three daily intraperitoneal doses of 0.9% NaCl, bleomycin (BLM), or a new 111In-bleomycin complex (BLMC, 15 microCi/g body weight) were administered to glioma-bearing mice. After therapy, tumors in mice treated with 111In-BLMC were smaller than those treated with BLM. Sixteen days after the first injection tumor size for 111In-BLMC-treated mice was 560 (240-1,030) mm3, 1,980 (1,400-3,290) mm3 for BLM (P less than 0.025), and 4,830 (2,580-9,180) mm3 for NaCl (0.1 less than P less than 0.2). Thirteen days after tumor transplantation glioma-bearing mice received single intratumor injection of 0.9% NaCl, BLM, or 111In-BLMC (1.5 mCi, carried by 0.5 mg BLM/g tumor weight). The average tumor size for 111In-BLMC was smaller than that for BLM by a factor of 2.5-3.7. Host weights for these two groups were similar, and morphologic abnormalities were not found in kidney or liver.