2500 Outpatient diagnostic hysteroscopies

OBJECTIVE

To evaluate the feasibility and acceptability of outpatient diagnostic hysteroscopy.

METHODS

The outcome of 2500 consecutive outpatient hysteroscopies was analyzed. Cervical dilation was performed when necessary and local anesthesia was not administered routinely. Endometrial biopsy and minor hysteroscopic procedures were carried out when indicated. Findings and outcome were compared according to patient characteristics.

RESULTS

The most common indication for hysteroscopy was abnormal uterine bleeding (87%). Hysteroscopy was performed successfully in 96.4%, and a complete view of the uterine cavity was obtained in 88.9%. Local anesthesia was used in 29.8% and was associated with the need for cervical dilation; both local anesthetic use and cervical dilation were significantly more often required in nulligravid, nulliparous, and postmenopausal women. Intrauterine pathology was diagnosed in 48%, the highest incidence being found in those 50-60 years old (53.7%). The presence of fibroids was the most common abnormality (24.3%) but was seen in only 6.8% of women older than 60 years. Conversely, the incidence of endometrial polyps increased with age, up to 20.5% in women over 60 years. Endometrial biopsy was performed in 68% and produced adequate tissue for histologic examination in 83.7%. Endometrial hyperplasia or carcinoma was detected in 1%. One hundred sixteen women (4.6%) underwent a minor hysteroscopic procedure.

CONCLUSION

Outpatient diagnostic hysteroscopy is both feasible and acceptable in the overwhelming majority of cases, with a high detection rate for intrauterine pathology. This procedure may become as routine in the 21st century as D&C has been in the 20th.

Regulation of rat liver tryptophan pyrrolase by its cofactor haem: Experiments with haematin and 5-aminolaevulinate and comparison with the substrate and hormonal mechanisms

1. The administration of haematin or 5-aminolaevulinate to rat enhances the activity of liver tryptophan pyrrolase; both endogenous and newly formed apoenzymes become strongly haem-saturated. Haem activation does not stabilize tryptophan pyrrolase. 2. Actinomycin D, puromycin or cycloheximide prevent the activation of the enzyme by 5-aminolaevulinate but not that by haematin. The latter is inhibited by haem-destroying porphyrogens. 3. The combined injection of either haematin or 5-aminolaevulinate with cortisol does not produce an additive effect, whereas potentation is observed when tryptophan is jointly given with either the cofactor or the haem precursor. 4. Further experiments on the substrate (tryptophan) mechanism of pyrrolase regulation are reported, and a comparison between this and the cofactor and hormonal mechanisms is made. 5. It is suggested that the substrate mechanism may also involve increased haem synthesis. 6. The role of tryptophan pyrrolase in the utilization of liver haem, and as a possible model for the exacerbation by drugs of human hepatic porphyrias, is discussed.

The role of free serum tryptophan in the biphasic effect of acute ethanol administration on the concentrations of rat brain tryptophan, 5-hydroxytryptamine and 5-hydroxyindol-3-ylacetic acid

1. Acute administration of ethanol exerts a biphasic effect on the concentrations of rat brain tryptophan, 5-hydroxytryptamine and 5-hydroxyindol-3-ylacetic acid. Both effects are associated with corresponding changes in the availability of circulating free tryptophan. 2. The initial increases in the above concentrations are prevented by ergotamine, are unaltered by allopurinol and are potentiated by theophylline, whereas the later decreases are prevented by both ergotamine and allopurinol. 3. It is suggested that the initial enhancement by ethanol of brain tryptophan metabolism is caused by catecholamine-mediated lipolysis followed by displacement of protein-bound serum tryptophan, whereas the activation of liver tryptophaan pyrrolase, which is produced by the same mechanism, leads to the later decreases in the brain concentrations of tryptophan and its metabolites. 4. The initial effects of ethanol can be reproduced by an equicaloric dose of sucrose, and a comparison of the two treatments alone could therefore be misleading. 5. The effects of ethanol on liver and brain tryptophan metabolism have also been examined in mice, and a comparison of the results with those previously reported suggests that the ethanol effects are strain-dependent.

Production of tolerance and physical dependence in the rat by simple administration of morphine in drinking water

1 Rats are capable of consuming solutions of morphine sulphate in drinking water ad libitum in the absence of taste-masking chemicals and without the need for scheduled provision or prior parenteral administration of the drug. 2 The success of this method depends on the initial provision of a 0.1 mg/ml solution of morphine sulphate. 3 When the drug concentration is increased to 0.4 mg/ml, the rats achieve an average daily intake of 50 mg/kg body wt. each. 4 Daily intake of morphine may be increased by at least about three fold by increasing the drug concentration to 1.2 mg/ml. 5 Oral morphine administration causes only a moderate loss in body weight. 6 Rats whose daily intake of the drug is 50 mg/kg exhibit tolerance to the analgesic action of morphine and show a drastic loss in body weight at 24 h after withdrawal and most of the behavioural symptoms of the naloxone-precipitated withdrawal syndrome. 7 It is suggested that this simple method of morphine administration is suitable for further biochemical and behavioural studies of the actions of the drug.

Animal liver tryptophan pyrrolases: Absence of apoenzyme and of hormonal induction mechanism from species sensitive to tryptophan toxicity

1. Liver tryptophan pyrrolase exists as holoenzyme and apoenzyme in rat, mouse, pig, turkey, chicken and possibly man. 2. The apoenzyme is absent from cat, frog, gerbil, guinea pig, hamster, ox, sheep and rabbit. 3. The hormonal mechanism of induction of the pyrrolase is absent from species lacking the apoenzyme. 4. The concentrations of tryptophan in livers and sera of these species are lower than in species possessing the apoenzyme. 5. Species lacking the apoenzyme or the hormonal induction mechanism have a deficient kynurenine pathway and are sensitive to the toxicity of tryptophan. 6. It is suggested that these species are not suitable as models for studying human tryptophan metabolism. 7. The possible significance of these findings in relation to veterinary and human neonatal care is discussed.

The regulation of rat liver tryptophan pyrrolase activity by reduced nicotinamide-adenine dinucleotide (phosphate). Experiments with glucose and nicotinamide

1. Chronic administration of glucose or nicotinamide in drinking water inhibits the activity of rat liver tryptophan pyrrolase, and subsequent withdrawal causes an enhancement. The enzyme activity is also inhibited by administration in drinking water of sucrose, but not fructose, which is capable of preventing the glucose effect. 2. The inhibition by glucose or nictinamide is not due to a defective apoenzyme synthesis nor a decreased cofactor availability. 3. The inhibition by nicotinamide is reversed by regeneration of liver NAD+ and NADP+ in vivo by administration of fructose, pyruvate or phenazine methosulphate. Inhibition by glucose is also reversed by the above agents and by NH4Cl. Reversal of inhibition by glucose or nicotinamide is also achieved in vitro by addition of NAD+ or NADP+. 4. Glucose or nicotinamide increases liver [NADPH]. [NADP+] is also increased by nicotinamide. [NADPH] is also increased by sucrose, but not by fructose, which prevents the glucose effect. Phenazine methosulphate prevents the increase in [NADPH] caused by both glucose and nicotinamide. 5. It is suggested that the inhibition of tryptophan pyrrolase activity by glucose or nicotinamide is mediated by both NADPH and NADH.

Enhancement of rat brain catecholamine synthesis by administration of small doses of tyrosine and evidence for substrate inhibition of tyrosine hydroxylase activity by large doses of the amino acid

Rat brain catecholamine synthesis is enhanced by small doses of tyrosine, but not by doses of 50mg/kg body wt. and above. It is suggested that these latter doses overcome the above enhancement by causing a substrate inhibition of tyrosine hydroxylase activity.

Decrease in circulating tryptophan availability to the brain after acute ethanol consumption by normal volunteers: implications for alcohol-induced aggressive behaviour and depression

Acute ethanol consumption by fasting male volunteers decreases circulating trytophan (Trp) concentration and availability to the brain as determined by the ratio of (Trp) to the sum of its five competitors ([Trp]/[CAA]ratio). These effects of alcohol are specific to Trp, because levels of the 5 competitors are not increased. The decrease in circulating (Trp) is not associated with altered binding to albumin and may therefore be due to enhancement of hepatic Trp pyrrolase activity. It is suggested that, under these conditions brain serotonin synthesis is likely to be impaired and that, as a consequence, a possible strong depletion of brain serotonin in susceptible individuals may induce aggressive behaviour after alcohol consumption. The possible implications of these findings in the relationship between alcohol and depression are also briefly discussed.

Randomized controlled trial of three doses of letrozole for ovulation induction in patients with unexplained infertility

The aromatase inhibitor letrozole is a novel agent that can be used as an alternative to clomiphene citrate for ovulation induction in patients with unexplained infertility. The dose of letrozole used has varied between studies, and this study aimed to compare the three most commonly used doses: 2.5, 5 and 7.5 mg. A total of 179 patients were randomly recruited in this prospective study with 58, 61 and 60 patients in each dosage group respectively. This study reports a significantly higher (P < 0.05) number of follicles (total, > 14 mm and > or = 18 mm) on the day of administration of human chorionic gonadotrophin in the 7.5 mg group, associated with significantly fewer (P < 0.05) days of stimulation. However the pregnancy and miscarriage rates were similar in the three groups. In conclusion, it seems that the use of higher doses of letrozole offers no advantage in terms of pregnancy rates over the lower (2.5 mg) dose.

The mechanism of inhibition of rat liver tryptophan pyrrolase activity by 4-hydroxypyrazolo(3,4-d)pyrimidine (Allopurinol)

1. Allopurinol (4-hydroxypyrazolo[3,4-d]pyrimidine) selectively inhibits the apotryptophan pyrrolase activity in homogenates of rat liver in vitro and after intraperitoneal administration. The inhibition is abolished by an excess of haematin. The allopurinol metabolite alloxanthine has no effect on the pyrrolase activity in vitro or after administration. Allopurinol also inhibits the activation of the enzyme in vitro by ascorbate, ethanol plus NAD(+), NADH, hypoxanthine or xanthine. It is suggested that these agents cause the conversion of a latent form of the pyrrolase into the apoenzyme, and that xanthine oxidase is not involved in this process. 2. The raised total pyrrolase activity observed after the administration of cortisol, cyclic AMP, tryptophan, salicylate or ethanol is lowered by allopurinol in vitro to the corresponding holoenzyme values. A similar effect is observed when allopurinol is administered shortly before cortisol or cyclic AMP. Pretreatment of rats with allopurinol completely prevents the enhancement of the pyrrolase activities by tryptophan, salicylate or ethanol. 3. It is suggested that allopurinol inhibits rat liver tryptophan pyrrolase activity in vitro and after administration by preventing the conjugation of the apoenzyme with its haem activator. The possible usefulness of combined allopurinol-tryptophan therapy of affective disorders is discussed.

Tryptophan pyrrolase, the regulatory free haem and hepatic porphyrias. Early depletion of haem by clinical and experimental exacerbators of porphyria

1. The importance of the early depletion of liver haem in the production of porphyria is discussed and further supporting evidence is presented from experiments with tryptophan pyrrolase, under conditions of exacerbation of experimental porphyria by therapeutic and other agents. 2. In addition to the early depletion of pyrrolase haem by porphyrogens, a further depletion is produced when rats are given a porphyrogen plus an analogue or one of 19 drugs known to exacerbate the human disease. 3. Non-exacerbators of human porphyrias do not cause a further early depletion of pyrrolase haem and it is suggested that this system may be used as a screening test for possible exacerbation of the disease by new and existing drugs. 4. A similar further early depletion of haem is produced by combined administration of lead acetate plus phenobarbitone, thus suggesting that the depletion is a more general phenomenon in experimental porphyria. 5. The relationship between tryptophan pyrrolase and the regulatory free haem is discussed. It is suggested that pyrrolase may play an important role in the regulation of haem biosynthesis.

The effects of chemical porphyrogens and drugs on the activity of rat liver tryptophan pyrrolase

1. Drugs such as phenobarbitone and phenylbutazone, which increase the concentration of microsomal haem and cytochrome P-450, also increase the saturation of rat liver apo-(tryptophan pyrrolase) with its haem activator, as does the haem precursor 5-aminolaevulinate. 2. At 4h after the administration of the porphyrogens 2-allyl-2-isopropylacetamide, 3,5-diethoxycarbonyl-1,4-dihydrocollidine and griseofulvin, the total pyrrolase activity is increased whereas the haem saturation of the apoenzyme is decreased. This decreased saturation is prevented by pretreatment of the animals with the inhibitor of drug-metabolizing enzymes, SKF 525-A. 3. Pretreatment of rats with the above porphyrogens inhibits the rise in holo-(tryptophan pyrrolase) activity produced by subsequent administration of cortisol, tryptophan and 5-aminolaevulinate with two single exceptions, the possible reasons for which are discussed. 4. At 24h after the administration, in starved rats, of a single daily injection of the above porphyrogens for 1 or 2 days, the holoenzyme activity is significantly increased. 5. It is suggested that the saturation of rat liver apo-(tryptophan pyrrolase) with its haem activator can be modified by treatment known to cause destruction, inhibition of synthesis, increased utilization and enhanced synthesis of liver haem. The possible involvement of the latter phenomenon in the aetiology of mental disorders in some patients with porphyria is discussed.

Enhancement of rat brain tryptophan metabolism by chronic ethanol administration and possible involvement of decreased liver tryptophan pyrrolase activity

1. Chronic ethanol administration enhances rat brain 5-hydroxytryptamine synthesis by increasing the availability of circulating tryptophan to the brain. This increased availability is not insulin-mediated or lipolysis-dependent. 2. Under these conditions, tryptophan accumulates in the liver and apo-(tryptophan pyrrolase) activity is completely abolished, but could be restored by administration of regenerators of liver NAD+ and/or NADP+. 3. All four regenerators used (fructose, Methylene Blue, phenazine methosulphate and sodium pyruvate) prevented the ethanol-induced increase in liver tryptophan concentration and the increased availability of tryptophan to the brain. 4. It is suggested that the enhancement of brain tryptophan metabolism by chronic ethanol administration is caused by the decreased hepatic tryptophan pyrrolase activity. The results are briefly discussed in relation to previous work with ethanol. 5. Fructose enhances the conversion of tryptophan into 5-hydroxyindol-3-ylacetic acid in brains of ethanol-treated rats, whereas Methylene Blue inhibits this conversion in both control and ethanol-treated animals.

Tryptophan pyrrolase in haem regulation. Experiments with administered haematin and the relationship between the haem saturation of tryptophan pyrrolase and the activity of 5-aminolaevulinate synthase in rat liver

1. Administration of haematin to rats decreases 5-aminolaevulinate synthase activity in whole liver homogenates. 2. An inverse relationship between this decrease and the increase in saturation of apo-(tryptophan pyrrolase) with haem is observed during the initial phase of treatment with haematin. 3. Significant changes in both functions are caused by a 1 mg/kg dose of haematin, whereas the maximum effects are achieved by the 5 mg/kg dose. 4. Prevention by allopurinol of the conjugation of exogenously administered haematin with apo-(tryptophan pyrrolase) renders this haem available for further repression of 5 aminolaevulinate synthase. 5. The various aspects of the relationship between synthase activity and the haem saturation of tryptophan pyrrolase are discussed.

Inhibition of rat liver tryptophan pyrrolase activity and elevation of brain tryptophan concentration by acute administration of small doses of antidepressants

1 Administration to rats of a 0.5 mg/kg dose of any of 19 antidepressants, but not that of many other drugs, causes a significant inhibition of the total enzyme and apoenzyme activities of liver tryptophan pyrrolase (of 24-48% and 37-65% respectively) and elevates brain tryptophan concentration by 13-66%. 2 When liver tryptophan pyrrolase activity is enhanced by pretreatment with cortisol or haematin, subsequent administration of a 0.5 mg/kg dose of some, but not other, antidepressants causes inhibition, which is weak (up to 38%). 3 This weak inhibition of the enhanced pyrrolase activity together with other pharmacological and physiological factors could explain the time lag between the start of antidepressant medication and the occurrence of a therapeutic response. 4 The cortisol-induced and haematin-activated pyrrolases respond differentially to inhibition by imipramine and amitriptyline, and this may explain the differential response to these two drugs of depressed patients in relation to urinary excretion of the noradrenaline metabolite 3-methoxy-4-hydroxyphenylglycol. 5 The results are discussed in relation to the mechanism of action of antidepressants and the possible involvement of disturbed hepatic tryptophan metabolism in depressive illness.

Induction of ovulation in idiopathic premature ovarian failure: a randomized double-blind trial

In this prospective randomized study, women with idiopathic karyotypically normal premature ovarian failure (POF) were treated with gonadotrophin-releasing hormone (GnRH) agonist and gonadotrophins with and without the addition of corticosteroids in an attempt to restore ovarian function. The study comprised 58 women with idiopathic POF randomly allocated to either GnRH agonists (GnRHa) plus gonadotrophin therapy with the addition of corticosteroids (29 patients) or GnRHa plus gonadotrophin therapy with placebo (29 patients). Ovulation occurred in six cases (20.7%) in the dexamethasone group versus three cases (10.3%) in the placebo group. There were two singleton pregnancies in the dexamethasone group. There were no reported complications from the use of dexamethasone apart from a sense of sleepiness and fatigue. The combination of corticosteroids with pituitary suppression followed by ovarian stimulation with gonadotrophin appeared to be beneficial in restoring ovarian function in patients with idiopathic POF and normal karyotype.

Guinea-pig liver tryptophan pyrrolase. Absence of detectable apoenzyme activity and of hormonal induction by cortisol and possible regulation by tryptophan

1. When assayed in fresh homogenates, guinea-pig liver tryptophan pyrrolase exists only as holoenzyme. It does not respond to agents that activate or inhibit the rat liver enzyme in vitro. Only by aging (for 30min at 5 degrees C) does the guinea-pig enzyme develop a requirement for ascorbate. 2. The guinea-pig liver enzyme is activated by the administration of tryptophan but not cortisol, salicylate, ethanol or 5-aminolaevulinate. 3. The tryptophan enhancement of the guinea-pig liver pyrrolase activity is prevented by 0, 34 and 86% by pretreatment with actinomycin D, cycloheximide or allopurinol respectively. 4. The guinea-pig liver tryptophan pyrrolase is more sensitive to tryptophan administration than is the rat enzyme. On the other hand, the concentrations of tryptophan in sera and livers of guinea pigs are 45-52% less than those in rats. 5. It is suggested that tryptophan may regulate the activity of guinea-pig liver tryptophan pyrrolase by mobilizing a latent form of the enzyme whose primary function is the detoxication of its substrate.

The mechanism of the antagonism by naloxone of acute alcohol intoxication

Naloxone lowers blood-ethanol concentration and causes a simultaneous reversal of the disturbances in the redox states of the hepatic nicotinamide-adenine dinucleotide (phosphate) couples in acutely-ethanol-intoxicated rats. It is suggested that these effects of naloxone form the basis of its antagonism of acute alcohol intoxication.

Effect of artemether alone and in combination with grapefruit juice on hepatic drug-metabolising enzymes and biochemical aspects in experimental Schistosoma mansoni

Artemether is an efficacious antimalarial drug that also displays antischistosomal properties. Grapefruit juice increases the oral availability of a variety of the CYP3A4 substrates. This study was designed to evaluate the effect of repeated administration of grapefruit juice with artemether on the hepatic activities of cytochrome P-450 (CYP450) and cytochrome b5 (cyt b5), on the serum levels of some biochemical enzymes and antischistosome efficacy. Results showed that administration of grapefruit juice alone induced more inhibition in the hepatic activities of CYP450 and cyt b5 than that produced by Schistosoma mansoni infection. Moreover, it enhanced degeneration of eggs and accelerated healing of the pathological granulomatous lesions. Treatment of S. mansoni-infected mice with artemether at a total dose of 300 mg/kg resulted in total and female worm burden reductions of 66.7 and 90.1%, respectively, hence protecting the host from damage induced by schistosome eggs. Treatment of S. mansoni-infected mice with artemether at 150 mg/kg reduced the total and female worm numbers by 43.3 and 54.4%, respectively, thus somewhat ameliorating hepatic granulomatous lesions compared with the infected untreated group. This was associated with no change in the hepatic activities of CYP450 and cyt b5 and in the serum levels of total protein, albumin, globulin and alanine aminotransferase compared with the uninfected control group. Coadministration of grapefruit juice with the lower dose (150 mg/kg) of artemether eliminated eggs and granulomatous reactions. In this group, the inhibitory effects of grapefruit juice on CYP450 and cyt b5 were apparent but serum liver enzymes were unchanged compared with the uninfected control group. Coadministration of grapefruit juice with artemether achieved complete protection of the host from damage induced by schistosomal infection.

Elective laparoscopic-assisted colectomy for diverticular disease. A prospective study in 50 patients

BACKGROUND

Although several recent reports described the different methods utilized for laparoscopic colon resection, only a few of them questioned whether the procedure is appropriate for the surgical treatment of diverticular disease. To assess this question, we performed a retrospective study of 50 consecutive patients operated using laparoscopic assistance to remove the sigmoid colon for diverticular disease.

METHOD

The surgical technique was a laparoscopically assisted procedure that included mobilization of the left colon and vascular ligation laparoscopically and then, via a small abdominal incision, division of the colon, removal of the specimen, and hand-sewn anastomosis.

RESULTS

The surgical goal was achieved in 46 cases, with a conversion rate of 8%. The mean operative time was 195 min (range 150-280 min). There was no mortality, and the morbidity rate was 14%. There were no complications directly related to the laparoscopic technique. The mean return of regular bowel habits was 3.2 days, and the median postoperative stay was 10 days.

CONCLUSIONS

These preliminary results suggest that laparoscopic-assisted sigmoidectomy can be used safely for the surgical treatment of diverticular disease.

Effects of acute paroxetine administration on tryptophan metabolism and disposition in the rat

1 The effects of acute oral administration of paroxetine on tryptophan metabolism and disposition were examined in the rat. 2 Basal liver tryptophan pyrrolase activity was inhibited by paroxetine in vitro and after oral administration. Maximum inhibition was caused by a 1 mg kg-1 dose. 3 Paroxetine administration also inhibited pyrrolase activity that had previously been enhanced by hormonal induction by cortisol or cofactor activation by haematin. The cortisol induction of the enzyme was, however, not inhibited by pretreatment of rats with paroxetine. 4 Paroxetine increased tryptophan availability to the brain, because of the above pyrrolase-inhibitory mechanism. Cerebral 5-hydroxytryptamine (5-HT) synthesis was accordingly enhanced, though this was apparent only with doses of the drug of up to 1 mg kg-1. With larger doses, decreased 5-HT turnover, probably as a result of 5-HT uptake inhibition, was the more dominant feature. 5 Paroxetine lowered circulating corticosterone concentration, but did not influence those of albumin, non-esterified fatty acids or glucose. 6 It is concluded that, in addition to inhibiting brain 5-HT turnover, paroxetine also, in common with 20 other antidepressants, enhances 5-HT synthesis by increasing brain tryptophan concentration secondarily to inhibition of liver tryptophan pyrrolase activity.