Carbogen and nicotinamide as radiosensitizers in a murine mammary carcinoma using conventional and accelerated radiotherapy

PURPOSE

To compare the radiosensitivity of mouse tumors treated in air with conventional and accelerated radiotherapy with that of tumors treated in carbogen alone or carbogen combined with nicotinamide.

METHODS AND MATERIALS

CaNT mammary tumors were irradiated with either 30 x-ray fractions in 6 weeks or 40 fractions in 26 days in air, carbogen alone, or carbogen combined with 120 mg/kg of nicotinamide (NAM), the latter given intraperitonealy 30 min before each fraction. The response to treatment was assessed using local control, weight loss, and metastasis-free survival.

RESULTS

Both carbogen and carbogen plus nicotinamide significantly increased tumor radiosensitivity; enhancement ratios (ERs) in the 6-week regimen were similar to those seen in the accelerated schedule. The majority of the effect was achieved by carbogen alone but the addition of NAM further enhanced tumor radiosensitization (ERs of 1.5 and 1.4 for carbogen in the conventional and accelerated schedule, respectively, were significantly lower than ERs of 1.7 and 1.6 obtained with carbogen plus nicotinamide; p < or = 0.005). Treatment protraction significantly increased radioresistance, especially when tumors were treated under air. An extra 1.5 Gy per day was required in air to counterbalance proliferation; in carbogen alone and carbogen plus nicotinamide a dose loss of 0.9 and 0.6 Gy per day was observed, respectively. Compared with treatments in air alone delivered in 6 weeks, acceleration of treatment combined with carbogen and nicotinamide gave the greatest increase in tumor radiosensitization (ER = 1.9). No toxic side effects and no detrimental changes in body weight were encountered when the sensitizers were administered 30 times (one fraction per day) or 40 times (two fractions per day). In both regimens, the incidence of metastases in mice treated with carbogen or carbogen plus nicotinamide was similar to that seen in animals treated in air. There was, however, a nonsignificant trend of a higher proportion of mice with metastasis in the accelerated schedule compared with the 6-week schedule.

CONCLUSIONS

In both conventional and accelerated experimental radiotherapy, carbogen alone or combined with a small clinically relevant dose of NAM were well tolerated, achieved large and significant increases in radiosensitization, and did not affect the incidence of metastases. The sparing of damage, resulting from extending the overall treatment time, was less when the sensitizers were administered than when irradiations were performed in air. The study suggests that clinical radiotherapy regimens, which aim to reduce hypoxic and/or tumor clonogen proliferation, would benefit from the use of carbogen, especially if the gas is combined with nicotinamide and treatment acceleration.

A sequence analysis of the beta-glucosidase sub-family B

This computational study is a summary of structural properties of the beta-glucosidase subfamily B. Computations were carried out using GCG package programs. All sequences used in this analysis were taken from the protein data bank. The multialignment and the phylogenetic tree of the beta-glucosidase sub-family B are shown. The conserved patterns: DGP, GRNFE, DPYL, KHF, SDW, GLD, VLLKN in the N-terminal region and FGYGLSY in the C-terminal part should be pointed out. C-terminal parts of the Butyrivibrio fibrisolvens and Ruminoccocus albus beta-glucosidase sequences can be aligned to the N-terminal region of the other members of the subfamily. A crossed homology model in sub-family B beta-glucosidases is described.

[Hematological differences between the effects of roller vs, centrifugal pump]

A secondary complication in the utilization of the CPB (cardiopulmonary bypass) is post-op bleeding due to alterations in the red blood cells and the activation sequences between coagulation, fibrinolysis and complement. We did this study with the objective to evaluate the behavior of the blood cells and coagulation factors using centrifugal pump (n = 12) roller pump (n = 12); we evaluated the consumption of blood products as well as measuring the amount of blood products used. There were no demographic differences between the two groups, the time on CPB was less than 85 minutes, blood flow in the centrifugal pump was maintained at an average of 3.6 l Vs 3.37 l in the roller pump, this being statistically significant. The blood values were compared in each group there were no statistically significant differences, however factor VIII, fibrinogen and platelets presented a tendency (p < 0.05) to be higher in the centrifugal pump group than in the control group (roller pump). Thus 1. In patients in whom we used centrifugal pump there was a tendency for preservation of factor VIII, platelets and fibrinogen. 2. There was no significant difference in the number of blood units transfused between the centrifugal vs roller pump. 3. patients in the centrifugal group were better perfused during CPB.4. 24 hrs. post-op, both groups showed no difference in post-op bleeding.

Nitric oxide modulates interleukin-2-induced proliferation in CTLL-2 cells

The role of the L-arginine–nitric oxide metabolic pathway was explored for interleukin-2-induced proliferation in the cytotoxic T lymphocyte clone CTLL-2. Specific inhibition of nitric oxide synthase significantly diminished, in a concentration-dependent manner,3H-thymidine uptake of CTLL-2 cells in response to different concentrations of interleukin 2. Withdrawal of L-arginine from culture medium resulted as potent as the higher inhibition obtained when blocking nitric oxide synthase with L-arginine analogues. Furthermore, intermedial concentrations of Larginine and exogenous nitric oxide donors were found for achieving optimal IL2-induced proliferation of CTLL-2. These findings prompted us to suggest that intra- and/or inter-cellular nitric oxide signalling may contribute to the modulation of the IL2 mitogenic effect upon cytotoxic T lymphocytes.

Nicotinamide pharmacokinetics in normal volunteers and patients undergoing palliative radiotherapy

The influence of nicotinamide formulation on absorption characteristics and incidence of adverse side-effects has been studied in normal volunteers and in patients undergoing radiotherapy. Escalating single or repeated oral doses of nicotinamide were administered in tablet or liquid form under fasting or non-fasting conditions. Drug absorption was slowed both by the presence of food in the stomach and by the administration of nicotinamide in tablet form compared with when it was dissolved in orange juice. Peak concentrations were generally slightly higher following the liquid preparation, but the incidence of adverse side-effects (chiefly nausea) was increased. A single dose of 9 g (88-97 mg/kg) nicotinamide in tablet form was well tolerated in two fasting normal volunteers, and in patients, doses of up to 133 mg/kg as tablets were tolerated twice/week for three weeks. Daily administration of 80 mg/kg nicotinamide was tolerated when given as tablets, but not in a liquid formulation. Neither the peak concentration nor the area under the concentration/time curve (AUC) of nicotinamide, nor the main metabolites of nicotinamide appeared to correlate with the incidence of toxicity.

Nitric oxide modulates interleukin-2-induced proliferation in CTLL-2 cells

The role of the L-arginine-nitric oxide metabolic pathway was explored for interleukin-2-induced proliferation in the cytotoxic T lymphocyte clone CTLL-2. Specific inhibition of nitric oxide synthase significantly diminished, in a concentration-dependent manner, (3)H-thymidine uptake of CTLL-2 cells in response to different concentrations of interleukin 2. Withdrawal of L-arginine from culture medium resulted as potent as the higher inhibition obtained when blocking nitric oxide synthase with L-arginine analogues. Furthermore, intermedial concentrations of Larginine and exogenous nitric oxide donors were found for achieving optimal IL2-induced proliferation of CTLL-2. These findings prompted us to suggest that intra- and/or inter-cellular nitric oxide signalling may contribute to the modulation of the IL2 mitogenic effect upon cytotoxic T lymphocytes.

The effect of magnesium sulfate on bleeding time in pregnancy

OBJECTIVE

The bleeding time is one of the most commonly used diagnostic tests to evaluate platelet-related hemorrhagic disorders. Magnesium has been shown in vitro to be a platelet antiaggregant. This study was conducted to evaluate the hypothesis that magnesium sulfate has no effect on the template bleeding time.

STUDY DESIGN

The study group consisted of 24 women who required magnesium sulfate in pregnancy. A blood cell count, platelet count, magnesium level, bleeding time, and mean arterial pressure were obtained before and 2 hours after magnesium sulfate infusion. Magnesium sulfate was infused beginning with a 6 gm intravenous bolus followed by 2 gm/hr. A template bleeding time was performed with a Simplate-II (Organon Teknika, Durham, N.C.) device. Two of the authors performed all the bleeding times. Data were analyzed with a paired t test and Wilcoxon rank test.

RESULTS

Fifteen (63%) patients received magnesium sulfate for tocolysis or before external cephalic version and nine (37%) for preeclampsia prophylaxis. No differences were found between the normotensive and hypertensive groups regarding maternal age, gestational age, initial bleeding time, or platelet count. Analysis of the entire study group revealed a prolongation of the bleeding time after magnesium sulfate (5.7 +/- 1.8 vs 6.6 +/- 1.9 minutes, p < 0.05); a lowering of the mean arterial pressure (p < 0.05), and a rise in the magnesium level (p < 0.05). Four patients (16.7%) had a postmagnesium bleeding time > 9 minutes.

CONCLUSION

Magnesium sulfate appears to prolong the bleeding time in pregnancy. The clinical significance remains to be determined.

Administration of nicotinamide during chart: pharmacokinetics, dose escalation, and clinical toxicity

PURPOSE

To determine nicotinamide pharmacokinetics in patients undergoing accelerated radiotherapy with the CHART regimen (continuous, hyperfractionated, accelerated radiotherapy) and given nicotinamide on a daily basis. The aim was to establish the pharmacokinetic profiles and their reproducibility during repeated administration, the maximum tolerated dose with fractionated radiotherapy, whether such a dose achieves sufficiently high plasma levels for radiosensitization, the optimal time interval between nicotinamide and irradiation, and toxic side effects.

METHODS AND MATERIALS

Nicotinamide plasma concentrations were determined using high performance liquid chromatography in 11 patients with advanced carcinomas of the head and neck and rectum being treated with CHART (36 fractions in 12 days). Kinetic profiles on the first day of radiotherapy and residual 24-h values were obtained in 10 patients; in four of these, full profiles were repeated two or three times during the course of treatment. In one other, a single sample per day was taken four times over the 12-day period. Doses of 80, 90, or 100 mg/kg/day were given 90 min prior to the second radiotherapy fraction on each day.

RESULTS

A dose of 80 mg/kg/day was well tolerated by all the patients. However, an increase of 10-25% in dose led to significant drug accumulation and major clinical toxicity, and none of the patients in the dose-escalation arm completed the planned regimen. Large interpatient variations in absolute peak concentrations were seen from 0.4 to 1.4 mumol/ml (mean 0.9 +/- 0.3; standard deviation (SD)). Of the five samples with the lowest peak levels, four were obtained from one patient. The time taken to peak concentration was also very variable from 0.8 to 4 h (mean 2.1 +/- 1.3 h; SD). In 70% of the samples, absolute plasma levels > or = 0.7 mumol/ml were reached within 1-2 h after administration and maintained for up to 6 h (mean 2.8 +/- 1.8 h; SD). There was a small but nonsignificant increase in the half-life of nicotinamide when the dose was increased from 80 to 90 or 100 mg/kg (7.1 h and 8.6 h, respectively).

CONCLUSIONS

In an accelerated regimen such as CHART, 80 mg/kg/day of oral nicotinamide is feasible and clinically tolerated, giving no or few side effects, and a 2-h interval between its oral administration and radiotherapy should achieve effective plasma levels in most patients.

[Evaluation of a triatoma infestans eradication program in rural dwellings from the IV region, Chile, by means of serology for Chagas disease in 0-10 years old children]

The present study deals with the evaluation of the effectiveness of the measures employed in the control of Triatoma infestans, the vector of Trypanosoma cruzi infection (Chagas' disease), in the IV region of Chile through a serological follow up program. For this reason, a serological survey has been carried out in 2,783 children, from 0 to 10 years, who live in rural high endemic areas of the region. The sera were tested using an indirect hemagglutination test (IHAT) and ELISA techniques with results agreeing in 99.9% of the samples. In children with positive serology xenodiagnosis was performed and blood samples from the corresponding mothers were submitted to serology for Chagas' disease. These additional tests should allow to distinguish between congenital infection and vectorial transmission. It was observed that vectorial transmission of T. cruzi was interrupted in some localities where entomological control has been applied for 10 years, or lowered in those which have been submitted to desinsectations in the last 5 years. On the other hand, a relatively high prevalence of the infection has been detected in some localities. These results suggest an apparent increase of vectorial transmission, indicating the need of readjusting the dwellings insecticide sprayings activities to improve the measures against the vector.

[Presence of Triatoma spinolai in human dwellings]

Triatoma spinolai is a wild species of triatomine existing exclusively in Chile, with scarce epidemiological importance in the transmission of Trypanosoma cruzi to man. It has been found in environments from 3000 meters down to the sea level. Exceptionally it has been found in human dwellings. In order to clarify the possibility of an adaptation of T. spinolai to human dwellings a study was undertaken in 50 rural-periurban dwellings from regions III, IV, V and Metropolitan in which this triatomine was found. The dwellings were classified in houses (35) and huts (15). The insect was trapped in 35 dwellings (24 houses and 11 huts) located in declivities (70%) and 15 dwellings (14 and 1) located in plains. This proportion is significantly higher than the average of 26.2% for dwellings located in declivities. It is concluded that the presence of T. spinolai in dwellings, more than a triatomine invasion is the result of the construction of huts or houses in the insect habitat.

[Epidemiology of Chagas disease in Chile. Frequency of human Trypanosoma cruzi infection by age groups and regions]

Chagas' disease is endemic in rural-periurban sections of the northern half of Chile which includes the first seven political-administrative regions of the country (18 degrees 30'-34 degrees 36' South lat.). Data concerning to the results of an indirect hemagglutination test for Chagas' disease performed to 15,418 rural-periurban and 45,119 urban inhabitants fron the chagasic endemic regions are presented. Migrations from rural-periurban to urban areas have contributed to the dissemination of Trypanosoma cruzi infection. General rates of infection for rural-periurban (r-p) and urban (u) sections were 16.7% and 1.9% respectively. The higher prevalence rates were detected in Region III with 27.2% (r-p) and 3.9 (u) and Region IV with 24.7% (r-p) and 3.5% (u), while the lower prevalence rates corresponded to Region VI with 7.0% (r-p) and 0.8% (u). Serological positivity increased parallelly with age in all regions.

Spasmolytic potential of some plants used in Mexican traditional medicine for the treatment of gastrointestinal disorders

The present investigation describes the effect on the isolated rat ileum of methanolic extracts derived from Conyza filaginoides (D. C.) Hieron (Asteraceae), Croton fragilis HBK. (Euphorbiaceae), Dodonaea viscosa Jacq. (Sapindaceae), Gymnosperma glutinosum (Spreng) Less. (Asteraceae), Parthenium tomentosum DC. var. stramonium (Greene) Rollins (Asteraceae), Potentilla thurberi A. Gray (Rosaceae), Pterogonum atrorubens (Englem.) H. Gross (Polygonaceae), Zornia venosa Mohlenbr. (Fabaceae) and Datura lanosa Barclay ex Bye (Solanaceae). In all the cases the extracts inhibited, in a concentration-dependent manner, the spontaneous contraction of the intestinal smooth muscle. The most active extract was that of D. viscosa. These findings tend to support the ethnomedical use of the selected species as spasmolytic agents in Mexican traditional medicine. Additionally, the potential antimicrobial activity of the extracts against pathogenic enterobacteria was investigated. Seven of the nine plants evaluated displayed antibacterial effects.

beta-Glucosidase families revealed by computer analysis of protein sequences

This computational study is a summary of how cloned beta-glucosidase subfamilies are organized. Computations were carried out using General Computer Group, Inc. (GCG) package programs. Twenty-two beta-glucosidases belonging to either cellulolytic or non-cellulolytic organisms were identified. The multialignment of a whole beta-glucosidase family is shown. Two sub-families, A and B, were clearly seen to exist. Sub-family A is further subdivided into sub-families A1 and A2. A1 includes vegetal beta-glucosidases and A2 includes prokaryotic enzymes. Sub-family B has three new sub-families, B1, B2, and B3. The enzymes in B2 are of yeast and/or fungi. Aspartic (D), glutamic (E) and histidine (H) residues, which are thought to be a part of the mechanism of the enzymatic hydrolysis are conserved. The well conserved amino acid sequences of the sub-family A are ITENGA; QUIEGA; HVD; and NEP. The well conserved amino acid sequences of the sub-family B are: SDW; and YN(R,K)(V,L)N.

Ca(2+)-independent nitric oxide synthase activity in human lung after cardiopulmonary bypass

BACKGROUND

Because surgery involving cardiopulmonary bypass induces a systemic inflammatory response, the effect of cardiopulmonary bypass on nitric oxide (NO) generation was investigated in human lung tissue.

METHODS

Nitric oxide synthase (NOS) activity was measured by the conversion of 14C-L-arginine to 14C-L-citrulline in tissue biopsy samples obtained before and after cardiopulmonary bypass.

RESULTS

The Ca(2+)-independent production of NO found before cardiopulmonary bypass was extremely low (1.5 (0.5) pmol citrulline/mg/min), but was increased after the bypass operation (23.6 (11) pmol/mg/min).

CONCLUSIONS

Ca(2+)-independent NOS activity was detected in human lung after cardiopulmonary bypass. This finding may provide an important insight into the pathogenesis of the tissue damage and acute phase response observed after such surgery.

[Prevalence of smoking in a general population in Valparaiso and Viña del Mar]

The aim of this work was to study the prevalence of smoking in an urban population from cities with low environmental pollution. From a sampling of basic and high school children, 1959 subjects coming from 406 homes were selected for the study and answered a questionnaire about smoking. The adjusted prevalence of smoking among subjects older than 10 years old was 36.5% and 40.8% in subjects older than 15 years old. Prevalence in males was 49.4% and 35% in female. However among subjects between 10 and 15 years old, females had a higher prevalence of smoking. Most subjects smoked 1 to 9 cigarettes/day, always aspirated smoke and consumed all the cigarette. The prevalence of passive smokers was 65.5%. It is concluded that the prevalence of smoking is high, that women are starting to smoke earlier than men and that no effort is being made to stop this habit.

Combined radioimmunotherapy and radiotherapy of human colon carcinoma grafted in nude mice

The effect of combined radioimmunotherapy (RIT) and fractionated external beam radiotherapy (RT) was assessed in two human colon cancer xenografts, Co112 and LS174T in nude mice. These tumors were selected for being resistant to RIT alone, as is usually the case in the clinical situation. Tumor-bearing mice were treated with a combination of five X-ray fractions over 5 days followed by RIT with two doses of 1.5 mCi 131I-labeled anticarcinoembryonic antigen monoclonal antibody F(ab')2. In Co112 and LS174T, RIT alone achieved a regrowth delay similar to that of fractionated RT with total doses of 28 and 26 Gy, respectively. In both tumor types, an additive therapeutic effect, measured as increased regrowth delay or local control, was observed when combining RT of different dose levels with RIT. Normal tissue responses were assessed by monitoring acute peak skin reactions and blood cell count. Bone marrow depression for the combination treatment was similar to that of RIT alone; relative to skin, at equitoxic levels, no mice bearing Co112 tumors were locally controlled with a 32 Gy RT dose alone, while this RT combined with RIT gave a local control of 100%. These studies show a therapeutic benefit when external beam RT is combined with RIT.

[Positivity of xenodiagnosis, according to age, in persons with positive serology for Chagas disease]

An analytical study of positive xenodiagnosis (XD), according to age distribution, in people with a positive indirect hemagglutination test (IHAT) for Chagas' disease has been carried out. A total of 1,137 IHAT for Chagas' disease positive persons were submitted to two wooden XD boxes containing 7 Triatoma infestans nymphs III each. The positivity (%) of XD in the different age groups was: 0-9 year-old (60.8), 10-19 (35.8), 20-29 (31.5), 30-39 (28.7), 40-49 (30.0), 50-59 (34.3) and > or = 60 (43.3). The 60.8% positivity of XD in children under 10 years of age is possibly due to the rather recent Trypanosoma cruzi infection in this age group and to diverse immunological mechanisms, which decrease with the age increasing.

Contribution of lethal mutations to excision assays for tumour cell survival

Conventional assays of cell survival determine only the proportion of colony-forming cells, assuming that all such cells are equivalent. However, cells surviving irradiation are reported to have lower plating efficiencies than unirradiated controls, suggesting an additional component of cellular damage that is ignored in conventional survival assays, but which could contribute to therapeutic outcome. Therefore we have examined the contribution of this additional form of damage to excision assays for cell survival in experimental tumours following both single dose and fractionated irradiation (10F/5 days) in vivo. Plating efficiencies were considerably lower for the long-term descendents of irradiated compared with non-irradiated cells. Expression of delayed reproductive death was reduced after fractionated radiation doses, only appearing after a substantial number of 3.4 Gy fractions had accumulated. Thus estimates of survival derived from single clonogenicity assays may underestimate the reduction in cell viability from a particular treatment. This could compromise assays for intrinsic radiosensitivity and mathematical modelling of the efficacy of treatment regimens.

Lobenzarit disodium inhibits the constitutive NO-cGMP metabolic pathways. Possible involvement as an immunomodulatory drug

Lobenzarit disodtulIl (CCA) is a novel immunomodulatory drug useful in the treatment of chronic inflammations. Its principal mechanism of action seems to be through enhancing the T suppressor/T helper lymphocyte ratio. However, the molecular basis for these actions remains unclear. In this study it was found that CCA inhibits the production of guanosine 3',5'-cyclic monophosphate almost completely when present in concentrations of 1 mM. Further results demonstrated that such inhibition could also be explained by interference in constitutive nitric oxide generation. In addition to previous findings, more insight into the molecular mechanism of action of CCA is provided.

Activation of phospholipase D by interleukin-8 in human neutrophils

Interleukin 8 (IL-8), a member of the C-X-C branch of the chemokine superfamily, stimulated the breakdown of 1-O-[3H]alkyl-2-acyl-sn-glycero-3-phosphocholine ([3H]EAPC) and the formation of 1-O-[3H]alkyl-2-acyl-phosphatidic acid ([3H]-EAPA) in human polymorphonuclear leukocytes (PMN) in the presence of cytochalasin B. In addition, the mass of diradyl-PA was increased with similar kinetics. In the presence of ethanol, 1-O-[3H]alkyl-2-acyl-phosphatidylethanol ([3H]EAPEt) was formed at the expense of [3H]EAPA formation, indicating the activation of phospholipase D by the cytokine. The effect was time- and concentration-dependent, reaching a plateau at 30 seconds with the maximally activating concentration of 120 nmol/L IL-8. Preincubation of cells with 1 microgram/mL Bordetella pertussis toxin inhibited the breakdown of [3H]EAPC and [3H]EAPA formation, indicating a role for a pertussis toxin-sensitive guanosine triphosphate-binding protein. Formation of phosphatidic acid (PA) correlated with activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, the oxidative burst enzyme, with both events occurring in the same concentration range. Inhibition of PA formation, by the presence of ethanol, also inhibited the oxidative burst stimulation by IL-8. Pretreatment of PMN with 10 nmol/L platelet-activating factor potentiated both [3H]EAPA accumulation and activation of NADPD oxidase by IL-8. Collectively, these data show that IL-8 stimulates the metabolism of choline-containing phosphoglycerides in human PMN and support a role for PA in the signaling mechanisms used by IL-8 to stimulate PMN function.

Activation of phospholipase D by interleukin-8 in human neutrophils

Interleukin 8 (IL-8), a member of the C-X-C branch of the chemokine superfamily, stimulated the breakdown of 1-O-[3H]alkyl-2-acyl-sn-glycero-3-phosphocholine ([3H]EAPC) and the formation of 1-O-[3H]alkyl-2-acyl-phosphatidic acid ([3H]-EAPA) in human polymorphonuclear leukocytes (PMN) in the presence of cytochalasin B. In addition, the mass of diradyl-PA was increased with similar kinetics. In the presence of ethanol, 1-O-[3H]alkyl-2-acyl-phosphatidylethanol ([3H]EAPEt) was formed at the expense of [3H]EAPA formation, indicating the activation of phospholipase D by the cytokine. The effect was time- and concentration-dependent, reaching a plateau at 30 seconds with the maximally activating concentration of 120 nmol/L IL-8. Preincubation of cells with 1 microgram/mL Bordetella pertussis toxin inhibited the breakdown of [3H]EAPC and [3H]EAPA formation, indicating a role for a pertussis toxin-sensitive guanosine triphosphate-binding protein. Formation of phosphatidic acid (PA) correlated with activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, the oxidative burst enzyme, with both events occurring in the same concentration range. Inhibition of PA formation, by the presence of ethanol, also inhibited the oxidative burst stimulation by IL-8. Pretreatment of PMN with 10 nmol/L platelet-activating factor potentiated both [3H]EAPA accumulation and activation of NADPD oxidase by IL-8. Collectively, these data show that IL-8 stimulates the metabolism of choline-containing phosphoglycerides in human PMN and support a role for PA in the signaling mechanisms used by IL-8 to stimulate PMN function.

Is there a role for ovarian stimulation and intra-uterine insemination after age 40?

The objective of this study was to determine the conception rate in infertile couples in which the female partner was > or = 40 years old and who had received ovarian stimulation treatment and intra-uterine insemination (IUI). It was a retrospective study of 77 patients who underwent a total of 210 treatment cycles. Protocols for ovulation induction included clomiphene citrate, human menopausal gonadotrophin (HMG) and clomiphene citrate plus HMG. Patients were monitored using transvaginal ultrasound, and two IUI were performed 24 and 48 h after the determination of urinary luteinizing hormone (LH) surge or human chorionic gonadotrophin (HCG) injection. A total of 11 pregnancies were reported, giving a pregnancy rate of 14% per patient and 5% per cycle. Eight spontaneous abortions occurred, giving a pregnancy wastage of 73%. In a previous comparative analysis of 543 patients < 39 years old receiving IUI and identical protocols of ovarian stimulation, 141 pregnancies were achieved, giving a pregnancy rate of 21% per patient and 10% per cycle. The miscarriage rate in that group was 18%. This report compares IUI results for women > or = 40 years with those obtained previously for younger women, and shows the very poor success rate in women > 40 years of age. This information will be important in the proper counselling of this group of patients, as well as indicating that a prompt recommendation for assisted reproductive treatment should be made soon after the failure of a few attempted cycles of ovarian stimulation treatment and IUI.

[Prefrontal dementias: clinical features and SPECT in 6 cases]

Six patients with primary degenerative dementias and frontal or frontotemporal hypoperfusion are reported. Five were diagnosed as Frontal Progressive Dementia (FPD), characterized by striking changes in personality and social behavior. The last patient had a progressive aphasia and a moderate cognitive impairment. We discuss the heterogeneity of FPD that includes Pick's disease, frontal lobe type dementia (Neary) and progressive subcortical gliosis. The usefulness of SPECT and the need of a brain bank are remarked.

Effects of glucose, ethanol, Hg(II) and Cu(II) on almond beta-glucosidase

The kinetic parameters of almond beta-glucosidase (beta-D-glucoside glucohydrolase; EC 3.2.1.21), using pNGP as substrate were kM = 2.24 +/- 0.11 mM and Vmax 588 +/- 25.1 U/mg protein. Only Hg(II) and Cu(II) showed irreversible inactivation of the enzyme. However, when these metals were present in the reaction system the inhibition effects were consistent with a mixed-type inhibition pattern (Cu(II) ki: 5.08 mM and Hg(II) ki: 0.07 mM). The glucose kinetic effect was also consistent with a mixed-type inhibition (ki = 406 mM) pattern with pNGP as varied substrate. Ethanol displayed the kinetic pattern of competitive inhibition (ki = 640 mM).