Intracellular calcium and hormone release from nerve endings of the neurohypophysis in the presence of opioid agonists and antagonists.

Rat neural lobes and isolated nerve terminals from the neurohypophysis were stimulated in the presence of different opioid agonists and antagonists. The secretion of arginine vasopressin and oxytocin and rise in cytoplasmic calcium induced by depolarization were analyzed by radioimmunoassay and the fluorescent probe fura-2, respectively. The kappa-agonists dynorphin A(1-13) and dynorphin A(1-8) did not affect electrically evoked release of vasopressin, although oxytocin release was slightly reduced. U-50 488, a relatively specific kappa-receptor agonist, had no effect on the amount of vasopressin or oxytocin secreted, although it significantly reduced K(+)-evoked changes in [Ca2+]i in isolated nerve endings. Two kappa-receptor antagonists, MR 2266 and diprenorphin, alone had no effect on vasopressin and oxytocin secretion from isolated nerve endings depolarized with potassium. Opioid agonists less selective for the kappa receptors, etorphin and ethylketocyclazocin, were found to inhibit the release of both vasopressin and oxytocin significantly. Naloxone, a nonselective opiate receptor antagonist, alone had no effect on vasopressin release but potentiated the electrically evoked release of oxytocin. Naloxone also could overcome the inhibitory effect of etorphin on oxytocin and vasopressin release observed after electrical stimulation of the neural lobe. A number of inconsistencies therefore exist between the effects of opioid agonists and antagonists on neuropeptide release and on the evoked changes in [Ca2+]i. In view of these inconsistencies and the high concentrations of opioid agonists and antagonists necessary to modify release, we conclude that it is doubtful that opioid molecules have a physiological role in controlling neurohypophysial secretion.


NMDA receptor-mediated long term modulation of electrically evoked field potentials in the rat medial vestibular nuclei.

The effect of high frequency stimulation (HFS) of the primary vestibular afferents on field potentials recorded in the ipsilateral Medial Vestibular Nuclei (MVN) was studied. Our results show that potentiation and depression can be induced in different portions of MVN, which are distinguishable by their anatomical organization. HFS induces potentiation of the monosynaptic component in the ventral portion of the MVN, whereas it provokes depression of the polysynaptic component in the dorsal portion of the same nucleus. The induction of both potentiation and depression was blocked under AP5 perfusion, thus demonstrating that NMDA receptor activation mediates both phenomena. Furthermore, the finding that the field potentials were not modified during perfusion with DL-AP5, as previously reported, supports the hypothesis that NMDA receptors are not involved in the normal synaptic transmission from the primary vestibular afferent fibres, but are only activated following hyperstimulation of this afferent system. Our results suggest that the mechanisms of long term modification of synaptic efficacy observed in MVN may underlie the plasticity phenomena occurring in vestibular nuclei.


Brain cortical tissue levels of noradrenaline and its glycol metabolites: effects of ischemia and postischemic administration of idazoxan.

The brain noradrenaline (NA) system is known to modulate ischemic neuronal damage, and the turnover of NA has been suggested to increase in the early recovery period following cerebral ischemia. Using HPLC and gas chromatography-mass spectrometry we analyzed the tissue levels of NA and its metabolites, 3,4-dihydroxyphenylethyleneglycol (DHPG) and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG), in rat brain cortex after 10 min of forebrain ischemia followed by 1 h of recirculation. The effect of idazoxan, given in cerebro-protective doses, as a bolus of 0.1 mg.kg-1 immediately after ischemia followed by 10 micrograms.kg-1.min-1 for 1 h, was also investigated. Ischemia decreased basal NA cortical levels from 384 ng/g tissue in control animals to 214 ng/g, while DHPG increased from 74 to 103 ng/g (+39%) and MHPG from 82 to 154 ng/g (+88%). Conjugated but not free DHPG increased, while both free and conjugated MHPG increased equally. The findings indicate an enhanced postischemic NA turnover with a major proportion of uptake and metabolism occurring extraneuronally, possibly secondary to a saturation of neuronal NA uptake in the postischemic phase. Idazoxan further increased NA turnover, as evidenced by higher postischemic levels of free MHPG and a higher MHPG/NA ratio. A correlation may exist between the protective action of idazoxan and its effect on NA turnover.


New drugs for asthma.

Several new drugs are now under development for the treatment of asthma, either as improvements to existing classes of therapy or as novel agents. Amongst bronchodilators, long-acting inhaled beta 2-agonists (salmeterol and formoterol) look very promising and there is also interest in selective phosphodiesterase inhibitors, K+ channel-openers and nitrodilators. There are several new inhaled corticosteroids under development and more selective agents include leukotriene antagonists, 5-lipoxygenase inhibitors, bradykinin and tachykinin antagonists and immunomodulators. In the future, adhesion molecule inhibitors and cytokine inhibitors may be developed.


Antihistamines in the treatment of asthma.

Histamine is an important mediator of asthma. The new anti-histamines which block histamine at the H1-receptor level also possess some anti-allergic properties. At current dosages they appear to be safe. These drugs are effective in the treatment of rhinitis and conjunctivitis but their role in asthma is still under investigation. At a dose higher than usually recommended, they were shown to block exercise-induced asthma and, inconstantly, the early phase reaction after allergen challenge. Their effect on the late phase allergic reaction as well as their clinical efficacy during trials is, however, less consistent. The indication of H1-blockers in the treatment of asthma is therefore limited, especially since doses higher than recommended may lead to adverse reactions.


Breath-actuated inhalers in chronic asthma: comparison of Diskhaler and Turbohaler for delivery of beta-agonists.

An open, randomized, cross-over study was performed to compare the efficacy and acceptability of two breath-actuated inhalers, the Turbohaler (T) and Diskhaler (D), for delivery of beta-agonists. Thirty six adults with chronic asthma requiring beta-agonists four times daily were treated with terbutaline 500 micrograms via T and salbutamol 400 micrograms via D four times daily, each period lasting four weeks. Additional bronchodilator via pressurized aerosol was permitted as required. Peak expiratory flow (PEF) was recorded in the morning (before and after beta-agonist) and in the evening. The mean morning PEF was higher during the first two weeks using T (295 l.min-1) than whilst using D (281 l.min-1, p < 0.01), but this difference did not persist during the second two weeks and there were no differences in post-bronchodilator PEF or rescue beta-agonist use. After four weeks, > 90% of patients used both inhaler devices efficiently and they were equally acceptable in terms of ease of use and convenience to carry. The Diskhaler and Turbohaler achieve similar clinical efficacy for delivery of beta-agonists.


Dopaminergic stimulation up-regulates the in vivo expression of brain-derived neurotrophic factor (BDNF) in the striatum.

We investigated the effect of dopamine on the in vivo expression of brain-derived neurotrophic factor (BDNF) in the striatum of mouse. BDNF mRNA expression in the striatum, which was quantified with the reverse transcriptase polymerase chain reaction, was up-regulated from 2 h after oral administration of levodopa, a precursor of dopamine. The increase was sustained for 16 h. Co-administration of haloperidol partially inhibited dopamine-induced BDNF enhancement. These data suggest that dopaminergic stimulation directly promotes the expression of BDNF in the striatum in vivo.


Structure of tubulin C-terminal domain obtained by subtilisin treatment. The major alpha and beta tubulin isotypes from pig brain are glutamylated.

Limited subtilisin digestion of the tubulin alpha, beta heterodimer has been used in this work to reduce the total number of tubulin isotypes from 20 for native to 9 for subtilisin-cleaved tubulin. This indicates that the major part of tubulin heterogeneity is located at the C-terminus of the molecule. The C-terminal peptides of both alpha and beta subunits of tubulin were purified by anion-exchange HPLC. Combined use of Edman degradation chemistry and mass spectrometry on the isolated peptides shows that subtilisin cleavage occurs at position Asp-438 and His-406 of alpha and Gln-433 and His-396 of beta tubulin chains. Quantitative analysis of our data show that cleavage at positions His-406 (alpha) and His-396 (beta) occurs with a low efficiency and indicates that the major isotypes of pig brain tubulin are modified by sequential attachment of 1 to 5 glutamic acid residues at positions Glu-445 or -435 of alpha and beta tubulin, respectively.


An alternative mechanism for the nitrogen transfer reaction in asparagine synthetase.

In the absence of crystallographic data, the mechanism of nitrogen transfer from glutamine in asparagine synthetase (AS) remains under active investigation. Surprisingly, the glutamine-dependent AS from Escherichia coli (AsnB) appears to lack a conserved histidine residue, necessary for nitrogen transfer if the reaction proceeds by the accepted pathway in other glutamine amidotransferases, but retains the ability to synthesize asparagine. We propose an alternative mechanism for nitrogen transfer in AsnB which obviates the requirement for participation of histidine in this step. Our hypothesis may also be more generally applicable to other glutamine-dependent amidotransferases.


Parathyroid carcinoma in a patient with non-secretory pituitary tumor: a variant of multiple endocrine neoplasia type-I?

We report a case of pituitary adenoma in association with parathyroid carcinoma as an unusual combination of multiple endocrine neoplasia (MEN). A 48-year-old man had a trans-sphenoidal hypophysectomy and transcranial partial removal of a recurrent pituitary chromophobe adenoma followed by a course of radiotherapy in 1980. Four years later, he developed hypercalcemic crisis from a parathyroid carcinoma with invasion to the adjacent thyroid gland and skeletal muscle. A hemithyroidectomy and resection of the left lower parathyroid gland was performed. Three years later, he had local recurrence and anterior chest wall metastasis accompanied by hypercalcemia. After resection of the remnant and metastatic lesion, eucalcemia was achieved. There was no family history of endocrine tumors. This case illustrates the rare association of a malignant parathyroid tumor and a chromophobe adenoma of the pituitary as a variant of MEN syndrome.


[The polyphosphoinisitide response evoked by different neuromediators after exposure to a helium-oxygen environment under increased pressure].

Male Wistar rats were subjected to normoxic helium-oxygen mixture under 40 kg/cm2 pressure with subsequent decompression. Their brain's Ach, dopamine, glutamate, substance P were shown to change the turnover rate of the synaptosomal PPI. The findings suggest an unspecific mechanism of action of high tension helium on the neurons. The data obtained shows the high pressure neural syndrome not to be connected with metabolic change of a single neurotransmitter.


Purification of a mature form of 60 kDa heat-shock protein (chaperonin homolog) from porcine kidney and its partial amino acid sequence.

1. We have purified a 58 kDa collagen-binding protein from a 4 M guanidine hydrochloride extract of porcine kidney. 2. This protein was identified as a mature form of 60 kDa heat-shock protein (HSP60, chaperonin homolog) based on its partial amino acid sequence. 3. Among 98 determined sequences of the porcine protein, 97 residues were identical with those deduced from nucleotide sequence of the cDNA encoding human HSP60.


The de Watteville Memorial Lecture: reproductive technologies and genetic advances in obstetrics and gynecology.

Public fascination with genetics and the new reproductive technologies seem ubiquitious. Although interest in genetic causation for diseases is not new, attention is increasing. There are several predictable reasons for this. One is the overall decrease in deaths due to infection. As a result, genetic factors producing birth defects loom relatively larger. This is also coupled with the public's increased desire for the ideal pregnancy, especially given a decreased population rate. Finally, the public's appetite is whetted by the increasing number of heritable diseases whose molecular basis is being elucidated. We shall focus on three general areas in which genetic technology increasingly impacts upon the obstetrician/gynecologist: genetics of pregnancy losses, genetics of sex determination and the common gynecologic disorders, and finally prenatal genetic diagnosis, particularly in preimplantation genetics and recovering fetal cells from maternal blood. Most of these topics are discussed in a recent text, where extensive references are available.


The impact of maternal age on pregnancy and its outcome.

There were 28,600 deliveries of 500 g or more to women at the Rotunda Hospital between January 1st 1985 and December 1st 1989. Of these, 595 were to women aged 40 years and over. Thirty-five variables of clinical significance were analyzed, comparing those of 40 years of age and more with those under 40. The older group had significant increases in gestational diabetes, ante-partum hemorrhage, fetal distress, prematurity, low birth weight and perinatal mortality. Chromosome congenital abnormalities were significantly higher, particularly Down syndrome. There were significantly increased rates of induction and cesarean section in the older women. Some evidence of interaction of age with other factors was found, however these were difficult to separate out in the clinical setting. We therefore recommend it wiser to manage all elderly gravidas in a high risk manner dealing with cases individually within this framework. Intervention should, however, need to be justified in the older as in the younger woman.


The preterm breech delivery in Zaria, northern Nigeria.

The preterm breech occurred in 31.21% of singleton breech presentations in a prospective study at Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria. The uncorrected perinatal mortality of 670.5 per 1000 deliveries was 1.7 times that for term breech presentations. Failure to book for antenatal care (50.94%), admission of cases in the second stage of labor (21.84%) and intrauterine fetal death on admission (38.64%) were associated factors of the high perinatal mortality. The mortality was extremely high in the very low birthweight fetus (less than 1500 g) delivered vaginally. Moreover, the cesarean section rate was associated with a 2.4 times higher perinatal morbidity and mortality rates than vaginal delivery.


Obstetric performance following conservative surgery for pelvic relaxation.

Over a period of three years (January 1987 to December 1990), 78 cases of conservative surgery for pelvic relaxation, either at our hospital or in some other hospitals, were studied. All of these patients were admitted in active labor or as cases of abortions. The complex nature of the problem of pelvic relaxation or genital prolapse is evident from the fact that we have encountered as many as six conservative operations in our series. The reproductive performance of a patient along with the time taken for the conception to occur after the surgery are emphasized in our study.


Ectopic pregnancy among past IUD users.

The relationship between return to fertility and pregnancy outcome in women with IUD removal for planned pregnancy as well as the frequency of ectopic pregnancy among all former IUD users in comparison with the general population was studied. The cumulative conception rate in the group of women with IUD removal for planned pregnancy (n = 748) was 93.7% after 5 years, 93.4% being intrauterine and 0.3% ectopic. Rates of ectopic pregnancy in women with IUD removed for planned pregnancy were 2.7/1000 women, 3.6/1000 deliveries and 2.9/1000 pregnancies vs. 3.9, 13.4 and 5.6 in the general population. Only when the number of deliveries is used as denominator, have these differences reached statistical significance (P less than 0.05). Except for bleeding/pain and PID removals (6.0 vs. 3.9), in all other groups of former IUD users the incidence of ectopic pregnancy was also lower than in the control group. From the results of this study it was concluded that former IUD users are not at an increased risk for ectopic pregnancy.


Outcome of cryosurgery for cervical intraepithelial neoplasia in a developing country.

Over a 2-year period cryosurgery was used to treat 73 women who were diagnosed by colposcopy and histologic studies to have cervical intraepithelial neoplasia (CIN). Follow-up was achieved for 70% at 5 years, a significant attendance rate in a developing country. The primary cure rate was 88.5% at 1 year and 90% at 5 years (excluding those lost to follow-up) in all patients with different grades of CIN. The therapy was free of major complications and we found no adverse effect of cryosurgery on subsequent reproductive function in those desiring pregnancy. We conclude that cryosurgery has gained wide acceptance in our geographic area particularly because of its low cost, efficacy and preservation of fertility. For these reasons we would strongly recommend its use provided adequate attention is paid to meticulous pretreatment evaluation and long-term follow-up after therapy.


Prospective analysis of short course chemotherapy in female genital tuberculosis.

Short course chemotherapy with 2SHRZ/7HR of 9 months duration was given in 41 proven cases of female genital tuberculosis. Thirty-two (78%) patients completed 9 months of therapy. Twenty-five (61%) were pronounced cured. Short course chemotherapy appears to be quite effective in patients of genital tract tuberculosis.


Pregnancy-associated hypertension in Maputo. A study on maternal characteristics and perinatal outcome in 1275 consecutive cases.

A total of 1275 consecutive cases of pregnancy-associated hypertension were registered in the Maputo Central Hospital (corresponding to 2.9% of a total of 43,794 city parturients). In the hypertensive and in the reference populations the following prevalence figures were registered, respectively: age below 25 years, 52% and 23% (P < 0.0005); nulliparity, 33% and 19% (P < 0.0005); twin pregnancies, 3.9% and 1.7% (P < 0.0005); stillbirths, 5.7% and 2.3% (P < 0.0005); and low birthweight (LBW), 22.9% and 10.7% (P < 0.0005). In the hypertensive population the prevalence of LBW newborns was 20.1% in the liveborn group, while it was 68.4% in the stillborn group (P < 0.0005). In the ongoing perinatal audit it was found useful to review hypertensive women separately, in order to assess current routines in cases of pregnancy hypertension.


Obstructed labor in Ibadan.

Over a period of 13 years, 380 cases of obstructed labor were managed amongst 39,456 deliveries. Absent prenatal care and poor intrapartum care at peripheral hospitals were major contributing factors. The average duration of labor in those with obstruction was three times that in the normal obstetric population. About 82% of patients with obstruction had an emergency cesarean section while 10% had destructive operations. The main etiological factor was unrecognised positional disproportion. Common associated complications were ruptured uterus, genital and wound sepsis. Maternal and perinatal morbidity and mortality were high. Adequate health education, incorporation of traditional birth attendants into health care programs and the provision of more health care centers will reduce the occurrence of this complication.


Assessment of fetal well-being: fetal movement count versus non stress test.

In this prospective study, comparisons were made between the results of fetal movement count as performed by either the attending staff or by the patients using the non stress test (NST). A total of 283 NSTs were performed in 200 patients who had singleton pregnancy of at least 32 weeks gestation with indications for assessment of fetal well-being. Fetal movement counts performed by the attending staff and by the patients were recorded on 241 and 170 occasions, respectively. The results showed that the best correlation between fetal movement count by the attending staff with NST was when the criteria of three or more fetal movements within 10 min was used. Likewise, the best correlation between fetal movement count by patients with NST was found when ten fetal movements within 2 h was used as a cut off point. The result of this study suggests the usefulness of fetal movement count performed either by attending staff or patients as a cheap and effective method of screening for good fetal well-being in places where NST is not readily available and may also be used as a screening for patients prior to further evaluation.


Haptoglobin as a sensitive marker of hemolysis in HELLP-syndrome.

In a prospective study we measured laboratory variables of hemolysis in 25 patients with HELLP-syndrome. Reduced haptoglobin levels were observed in all 25 patients at diagnosis. Elevated bilirubin and plasma hemoglobin levels were observed in 5/25 patients while an abnormal peripheral blood smear was found in 11/25 patients. Our results suggest that haptoglobin is a sensitive parameter for early detection of moderate hemolysis in HELLP-syndrome and should be included in laboratory screening to aid diagnosis.


Ovarian masses in postmenopausal women.

In an attempt to evaluate the significance of malignant tumors in postmenopausal women, we reviewed the charts of 380 postmenopausal women over 50 years of age, operated on in our department for adnexal masses, from January 1st 1980 to December 31st, 1989. Two hundred and ninety-seven benign (78.2%) and 83 malignant (21.8%) tumors were found. In our group of patients the rate of malignancies increases significantly with the size of the lesion. Of the malignant tumors 25.1% were in the age group 50-60 years, 16.3% in the age group 60-80 years and 58.6%, a fourfold increase in the rate of malignancies, in the over 80 age group. Although surgery might pose problems in older patients, we conclude, on the basis of our experience, that surgical treatment should be considered for all adnexal masses in postmenopausal women.


Declining mortality in international sterilization services.

Between 1973 and 1988, AVSC supported 1,516,478 female sterilizations and 401,856 vasectomies in 50 countries. Overall, 73 deaths were attributable to voluntary sterilization procedures (yielding mortality rates of 4.7 deaths per 100,000 female sterilizations and 0.5 per 100,000 vasectomies). Causes of death, in order of frequency, were anesthesia (22), intestinal injury (20), infection (19), intra-abdominal hemorrhage (6) and other (6). The female sterilization mortality rate declined from 7.1 per 100,000 procedures in 1973-1981 to 3.7 per 100,000 in 1982-1988. Safer anesthesia practices and improved infection control contributed most to this decline. The mortality rate related to surgical errors declined proportionately less than the rates related to anesthesia and infection. Contraceptive sterilization has become a very safe procedure in these 50 countries, where anesthesia (local and general), surgical technique (minilaparotomy and laparoscopy) and timing of the procedure (interval and postpartum) vary substantially. Future deaths will probably be rare. However, expert surgeons should review each case because identifying the most likely cause of death is always complex and these analyses help shape surgical contraception practices.


Nonmalignant conditions of the breast. ACOG Technical Bulletin Number 156--June 1991 (Replaces No. 71, September 1983).

The evaluation of benign conditions of the breast requires constant vigilance in relation to diagnosis, treatment, and, importantly, exclusion of carcinoma. Fortunately, the clinical presentation and epidemiologic considerations of the various benign lesions of the breast provide information permitting a fairly precise diagnosis. Fibrocystic changes, with its various subconditions, certainly is the most prominent benign condition, but other benign alterations occurring in the breast are also somewhat common. The management of fibroadenomas requires precise judgment and depends partly on the patient's age and the characteristics of the growth. Acute infections such as mastitis require prompt intervention and treatment. Recurring infections such as a subareolar abscess should be treated specifically in an aggressive and definitive manner. Infrequently occurring problems such as superficial thrombophlebitis, galactocele, and fat necrosis can be very uncomfortable, and occasionally, their diagnosis will be more difficult to establish. They, however, demand accurate diagnosis and definitive treatment. The axiom of excisional biopsy and histologic evaluation of any lesion that does not respond to treatment is the most important guideline in the treatment of benign breast disease.


The effect of desogestrel for hormone replacement therapy on the blood lipid profiles of postmenopausal women.

To determine the effect of a hormone replacement protocol containing conjugated equine estrogens and desogestrel (which has a highly selective progestogenic and low androgenic effect) as the progestogen, on the plasma lipid profile, as compared with two other hormone replacement treatments (HRT). Eighty-nine healthy postmenopausal women were divided prospectively into four groups. A control group of 24 women did not receive HRT. Twenty-nine women received conjugated equine estrogen and medroxyprogesterone, and 13 women received a protocol containing estradiol, estriol and norethisterone acetate. Fasting blood lipid was taken at the end of each third cycle. The cumulative therapeutic response was calculated in each group as compared with initial values and between groups. Significance was analyzed by t-tests. A protocol containing desogestrel significantly decreased low-density lipoprotein cholesterol (27%; P < 0.05) and increased high-density lipoprotein cholesterol (HDL-C) by 30% (P < 0.05%) after 9 months. The ratio of total cholesterol to HDL-C also decreased significantly (44%; P < 0.05). The most beneficial effect on plasma lipid profile was obtained with an HRT protocol containing desogestrel as the progesterone.


Female voluntary surgical contraception via minilaparotomy under local anesthesia.

To examine changes in prevalence and acceptance of sterilization methods in a developing country from 1986 to 1990. Data from 5182 voluntary female sterilizations performed at 52 service sites in Nigeria were retrospectively reviewed for sterilization method, anesthesia technique, demographic factors, and patient acceptance. The annual number of sterilization procedures increased dramatically over this period from 688 in 1986 to 1911 in 1989. Overall, 74.3% of the procedures were performed by minilaparotomy under local anesthesia (ML/LA), 6% by laparoscopy/general anesthesia, and 19.7% by laparatomy/general anesthesia. ML/LA was found to be a very safe method, with a complication rate of 1.4%. 98.6% of ML/LA patients expressed complete satisfaction with the procedure. Female sterilization increased in acceptance in Nigeria over the period 1986-1990 concomitant with the increased use of ML/LA. This approach is safe, cost-effective, and appropriate for the developing world.


The role of the village midwife in detection of high risk pregnancies and newborns.

The preliminary findings of a prospective study of perinatal, neonatal and maternal mortality carried out in a rural community of Sudan are reported. Out of 6275 deliveries monitored over a period of 3 years, 150 stillbirths, 167 neonatal deaths and 27 maternal deaths were observed. An intervention program to upgrade the skills of the village midwives started in the middle of the second year. There was a 25% reduction in the risk of unfavorable outcome of pregnancy (i.e. stillbirth and neonatal death) in the third year relative to the first 2 years. Peer review of the 40 village midwives who took part in the study revealed their tremendous potentials in mobilization of mothers as well as participation in primary health care. Their role in detection of high risk pregnancies and newborns cannot be overemphasized.


Maternal tetanus toxoid coverage during pregnancy in Ile-Ife, Nigeria.

A cluster survey on maternal tetanus toxoid (TT) coverage was carried out in the Ile-Ife Central Local Government Area. Out of the 896 mothers of babies 0-12 months old who were interviewed, 668 (74.6%) claimed they received TT during pregnancy, this was confirmed in 37 (4.1%) and in only 25 (2.8%) of these cases could the babies be said to have been protected from neonatal tetanus (NNT) at birth. About 35% of the babies were delivered at home/churches where most babies with NNT are usually born.


Histiocytosis X and vulvar ulceration.

Vulvar ulceration is a rare manifestation of histiocytosis X. A 13-year-old girl had a nonhealing vulvar ulcer for 1 year. She had been in remission from histiocytosis X and the ulcer was not recognised as a sign of disease recurrence until tissue biopsy was obtained for histopathological and immunohistochemical studies. This article stresses the importance of establishing an accurate diagnosis when chronic vulvar ulcers are encountered and reviews the literature on this uncommon presentation of histiocytosis X.


Risk factors for maternal mortality: results of a case-control study conducted in Conakry (Guinea).

To assess the risk factors of maternal mortality in an urban area of West Africa (Conakry, capital of Guinea). A case-control study where 102 maternal deaths were compared with 338 control women who had given birth and survived, during 1 year (from July 1, 1989 to June 30, 1990). Of all the socio-demographic variables studied, only a low family income (R = 2.6; 1.1-6.5) was found to be a risk factor for maternal death In the obstetrical part of the survey, neither parity nor the number or location of pre-natal consultations constituted risk factors. However, the presence during pregnancy or delivery of signs of infection (R = 3.7; 1.4-9.8), anemia (R = 2.1; 1.1-4.1), hypertension (R = 19.8; 5.8-67.8) and dystocia (R = 9.0; 3.7-21.5) were found to be the main predictive risk factors of maternal death. The maternal mortality risk was multiplied by 12 if the women had had a cesarean section, and by 4 in the case of complications in the post-partum period. To achieve substantial reductions in maternal mortality levels, work must be done on these specific risk factors, and future programs must urgently be concentrated on a higher standard of pre-natal monitoring, obstetrical emergency facilities and training of obstetrical staff.


Management of patients with poor symphysis pubis-fundus growth by Doppler flow velocimetry of the umbilical artery--an effective method to detect the fetus at risk.

This study evaluated Doppler flow velocimetry of the umbilical artery in patients with suspected intrauterine growth retardation as detected by poor symphysis-fundus growth (SFG). The sensitivity of Doppler in detecting light for gestational age babies and intrauterine growth retardation was poor. Antenatal complications, neonatal morbidity and perinatal mortality occurred significantly more frequently in patients with abnormal flow. Doppler flow velocimetry is an excellent test to identify babies at high risk for perinatal morbidity and mortality, when poor SFG is present.


The use of intradepartmental audit to contain cesarean section rate.

In one department practicing critical review of indications for cesarean delivery, the overall LSCS rate was maintained at 12.3%, 11.1%, 11.2% and 11.4% for 1987, 1988, 1989 and 1990, respectively. A highly significant (P = 0.0013) reduction of 26.8% was observed in the LSCS rate for cephalo-pelvic disproportion between 1987 and 1990. Perinatal mortality rate per 1000 births remained low at 8.25, 7.05, 9.39 and 5.83 for infants weighing 500 g or more.


Annulin, a protein expressed at limb segment boundaries in the grasshopper embryo, is homologous to protein cross-linking transglutaminases.

Annulin, a protein whose general stage- and position-specific expression pattern in the grasshopper embryo is described in the companion paper, is expressed in epithelial annuli in developing limbs. Here, we show that these annuli comprise narrow circumferential bands of epithelial cells at the boundaries of limb segments. At most boundaries, expression of annulin precedes the first morphological signs of segmentation. The most distal cells in a band underlie the boundary invagination. Bands arise in a stereotyped order and, within a band, expression occurs in an ordered circumferential progression. Annulin has a molecular weight of about 97 kDa and appears to be intracellular and peripherally associated with the inner leaflet of the cell membrane. Using the monoclonal antibody 7H7, two overlapping cDNA clones encoding this protein were isolated from an embryonic Schistocerca cDNA expression library. The nucleotide and deduced amino acid sequences indicate that the annulin protein does not contain either a signal sequence or a transmembrane domain. By sequence comparison, annulin appears to be a transglutaminase, one of a family of enzymes that have protein cross-linking activity. Its expression pattern within the limb and the embryo is associated with areas undergoing morphogenetic rearrangements, movements, or rapid cell division. It may stabilize cells under mechanical stress or participate in some other way in these morphogenetic activities.


Two distal-less related homeobox-containing genes expressed in regeneration blastemas of the newt.

Urodeles, like the newt, are able to replace their limbs and tail following amputation by the formation of a blastema, a mass of proliferating mesenchymal cells originating from the tissue adjacent to the cut surface. As this capacity may involve genetic control, we investigated in adult tissues the expression of genes controlling embryonic development. We screened a newt cDNA library with a redundant oligonucleotide specific to the highly conserved third helix of the DNA-binding domain of homeobox genes. Five classes of cDNA have been isolated. We report the nucleotide sequence and the tissue distribution of two of them, NvHBox-4 and NvHBox-5. The amino acid sequences of both homeodomains are highly homologous (83 and 87% identity) to distal-less, a Drosophila homeobox gene expressed during the development of appendages. NvHBox-4 and NvHBox-5 express respectively 2.8 and 2 kb transcripts. The pattern of expression of both genes is identical in adult tissues of the newt. Polyadenylated transcripts are detectable in the forelimbs, hindlimbs, the tail, flank, and brain as well as in limb and tail blastemas. Analysis of dissected tissue from the hindlimbs indicated that the expression of both genes is restricted to the skin. This work is a first step toward understanding the possible relation between sustained expression of homeobox-containing genes in adult newt tissues and regeneration potential.


Cloning and characterization of a novel Drosophila Wnt gene, Dwnt-5, a putative downstream target of the homeobox gene distal-less.

The Wnt gene family in vertebrates comprises at least 11 distinct genes but the only family member previously identified in Drosophila has been the segment polarity gene wingless (wg), the ortholog of vertebrate Wnt-1. In this report we describe the isolation of a novel Drosophila Wnt gene, Dwnt-5, which differs significantly from wg in both the pattern of its expression during embryogenesis and the predicted structure of its product. Dwnt-5 encodes a polypeptide of 112 kDa, which is more than twice as large as the products of previously known Wnt genes. The protein shares homology with other Wnt sequences in its carboxy-terminal half only and is most closely related to the products of vertebrate Wnt-5a and Wnt-5b. Dwnt-5 is expressed in a complex pattern during Drosophila embryogenesis. At the extended germ band stage, however, transcripts accumulate specifically in the nascent limb primordia of the head and thoracic segments. We show that this elevated expression depends on the activity of the homeobox gene Distal-less (Dll) and suggest that the Dwnt-5 gene may constitute a downstream target of Dll that acts in the specification of these primordia.


Contractile protein isoforms in muscle development.

The contractile proteins of skeletal muscle are often represented by families of very similar isoforms. Protein isoforms can result from the differential expression of multigene families or from multiple transcripts from a single gene via alternative splicing. In many cases the regulatory mechanisms that determine the accumulation of specific isoforms via alternative splicing or differential gene expression are being unraveled. However, the functional significance of expressing different proteins during muscle development remains a key issue that has not been resolved. It is widely believed that distinct isoforms within a family are uniquely adapted to muscles with different physiological properties, since separate isoform families are often coordinately regulated within functionally distinct muscle fiber types. It is also possible that different isoforms are functionally indistinguishable and represent an inherent genetic redundancy among critically important muscle proteins. The goal of this review is to assess the evidence that muscle proteins which exist as different isoforms in developing and mature skeletal and cardiac muscles are functionally unique. Since regulation of both transcription and alternative splicing within multigene families may also be an important factor determining the accumulation of specific protein isoforms, evidence that genetic regulation rather than protein coding information provides the functional basis of isoform diversity is also examined.


Cholinergic differentiation of rat sympathetic neurons in culture: effects of factors applied to distal neurites.

Cholinergic properties are induced in sympathetic neurons by several factors applied to entire neurons in culture. Evidence from work with the rat sweat gland model indicates that factors located in target tissues can induce cholinergic differentiation in vivo. We now report that when leukemia inhibitory factor (LIF), heart cell-conditioned medium (HCCM), or dermal fibroblast-conditioned medium (DFCM) is applied to only distal neurites in compartmented cultures of rat sympathetic neurons, the neurons exhibit an increase in specific choline acetyltransferase activity and a concomitant decrease in levels of tyrosine hydroxylase. LIF, HCCM, and DFCM also induce neurite fasciculation, thus suggesting an additional role of cholinergic switching factors in regulating axon-axon and/or axon-substrate adhesion. These results demonstrate that rat sympathetic neurons have the cellular machinery to respond to cholinergic differentiation cues located in peripheral targets, analogous to the response to nerve growth factor.


Second signal for T lymphocyte activation: multiple targets for pharmacological modulation.

Complete T cell activation requires at least two signals. The first is delivered through the antigen-specific T cell receptor, whereas the second is generated by cognate interactions through adhesion molecules of T cells and antigen-presenting cells and/or by cytokines produced by antigen-presenting cells. The delivery of the two signals results in gene transcription, cytokine secretion, expression of new cell surface molecules including cytokine receptors, and cellular proliferation. Reference immunosuppressive agents were shown to act at different subsequent stages of T cell activation and proliferation. Among immunostimulating compounds, those which can enhance T cell responses are likely to modulate or replace the second signal in T cell activation, or alternatively, to act at later stages such as cytokine secretion, cytokine receptor expression or response to cytokine signals. For the purpose of in vitro evaluation of the activity of immunomodulators on the second signal of T cell activation, we devised a model of accessory cell depletion and reconstitution. This model allows the capacity of a given compound to enhance surface adhesion molecule expression or to trigger monocyte cytokine synthesis to be tested, and these effects to be assessed on T cell proliferation.


[Severe psychiatric disorders associated with severe acute colitis].

Acute colitis occurring in patients suffering from psychiatric illnesses is believed to be linked to the intake of psychotropes. From 1983 to 1989, the authors observed, in three Hepato-gastroenterology units, 10 cases of acute colitis in patients suffering from serious psychiatric disorders, most of them inpatients of mental hospitals. The detailed study of 7 of these cases emphasized a certain number of common features: there was no previous history of digestive disease, the psychiatric illness was serious and longstanding, acute colitis was severe, and there was no recurrence during clinical and endoscopic follow-up averaging 4.3 years. Of these 7 patients, 2 were not taking psychotropes at the time of colitis or after, 2 had discontinued their treatment for a few days, and 2 had not stopped taking psychotropes. One patient died. The short-term and long-term evolution in these cases was not influenced by the intake or not of psychotropes. The pathogeny of this colitis is yet to be determined: infection is the most likely origin.


[Benign papillomatosis of Wirsung's duct associated with adenomyoma of the distal common bile duct].

We report the case of a 42 year-old man, with a history of alcohol and tobacco abuse, who was referred for suspicion of carcinoma of the head of pancreas. Pancreatoduodenectomy was performed. Histological study demonstrated obstructive benign adenomyoma of the distal common bile duct associated with villous papillomatosis of the pancreatic ducts and patchy lesions of chronic pancreatitis. Two years later, the patient was completely asymptomatic, but the risk of malignant transformation of villous papillomatosis requires periodic examination of the remaining pancreas and biliary tract.


Influence of plasma proteinase inhibitors and the secretory leucocyte proteinase inhibitor on pancreatic elastase-induced degradation of some plasma proteins.

Pancreatic elastase-induced degradation of some plasma proteins was studied in an in vitro model. The digestion was correlated with the degree of saturation of the alpha 1-proteinase inhibitor (alpha 1PI) and also with varying amounts of secretory leucocyte proteinase inhibitor (SLPI). SLPI was found to inhibit pancreatic elastase showing a Ki of about 10(-7) M for the complex. On the addition of human pancreatic elastase to plasma cleavage of C3, kininogen, fibrinogen and fibronectin was observed when the alpha 1PI approached saturation. In the present in vitro model it was possible to block the cleavage of the four plasma proteins, mentioned above completely with SLPI. Addition of the inhibitor also decreased the consumption of alpha 1PI.


Endotoxin-induced alterations in rat colonic water and electrolyte transport.

This study examines the effects of endotoxin on intestinal water and electrolyte transport in adult male rats. Endotoxin (1.55 mg/kg, intravenously) reduced in vivo colonic saline absorption 61% in 1 hour. In vitro unidirectional and net 22Na and 36Cl fluxes showed that endotoxin significantly decreased net colonic 22Na absorption compared with control colons (0.3 +/- 1.7 vs. 4.8 +/- 1.1 microEq/h x cm2). Although endotoxin had no significant effect on basal short circuit current (Isc) and conductance, 3H-inulin flux studies suggested an increase in colonic permeability. Isc responses to the 5'-cyclic adenosine monophosphate (cAMP)-dependent secretagogues prostaglandin E2 (1 mumol/L) and vasoactive intestinal peptide (0.1 mumol/L) were diminished by 80% and 50%, respectively. However, cytosolic cAMP-dependent protein kinase activity under basal and stimulated (6 mumol/L 8-bromo-cAMP) conditions was not altered by endotoxin treatment. The Isc responses to 10 mumol/L bethanechol, a Ca(2+)-dependent agonist, were not effected by endotoxin treatment. It was concluded that endotoxin significantly affects colonic transport function and may contribute to the development of diarrhea in inflammatory bowel diseases.


Colorectal cancer risk and mortality in patients with ulcerative colitis.

A regional inception cohort of 1161 ulcerative colitis (UC) patients was followed up from diagnosis to the end of 1987. The follow-up rate for death and occurrence of cancer was 99.9% (median observation time, 11.7 years; range, 0-26 years). One hundred forty-one deaths were observed, 26 caused by UC or complications thereof. No significant excess mortality was found after the first year, but in the year of diagnosis the relative risk of death was 2.4 (P < 0.001). The cumulative colectomy rate 25 years after diagnosis was 32.4%. The initial extent of disease significantly influenced the colectomy probability, being 35% in total colitis, 19% in substantial colitis, and 9% in distal colitis within the first 5 years after diagnosis. Six patients developed colorectal cancer within the observation period. Compared with the expected number of 6.6, the relative risk for patients with UC was 0.9. The calculated cumulative cancer incidence was 3.1% after 25 years (95% confidence limits, 0.0-6.8). The calculated lifetime risk (0-74 years) for development of colorectal cancer was 3.5% for UC patients compared with 3.7% for the Danish population. It is concluded that with an active approach to medical and surgical treatment, as practiced here, patients whose colons are left intact bear no significantly increased risk of colorectal malignancy.


Neoplasia and hyperplasia of large bowel: focal lesions in an abnormal epithelium.

Expression of brush border hydrolases can reflect the state of differentiation of an epithelium. To determine if expression of these enzymes is disordered in patients with neoplastic or hyperplastic lesions, the activities of alkaline phosphatase, maltase, and dipeptidyl peptidase IV were measured spectrophotometrically in colonoscopic biopsies from the proximal and distal colon and rectum in 50 controls, 17 patients with large bowel adenomas, 29 with carcinoma, and 9 with hyperplastic polyps. In normal controls, a descending cecorectal gradient of alkaline phosphatase activities and an ascending gradient of maltase activities were seen (P < 0.001). Though regional patterns of expression were generally preserved in disease groups, there were significant differences of activities across patient groups for alkaline phosphatase (greater in cancer, adenoma, and hyperplastic groups than in normals; P < 0.05) and for dipeptidyl peptidase IV (greater in hyperplastic polyp group than normals, greater in adenoma than cancer group; P < 0.05). Compared with normal controls, abnormalities of site-specific activities were confined to the rectum in patients with adenoma (maltase decreased, P = 0.02; dipeptidyl peptidase IV increased, P < 0.01) or with carcinoma (alkaline phosphatase increased, P = 0.03) but dipeptidyl peptidase IV activities were increased in all regions in bowels bearing hyperplastic polyps (P < 0.01). These data suggest that neoplastic and hyperplastic lesions, while focal in nature, occur in large bowel epithelium, which is diffusely abnormal in terms of its expression of these enzymes.


Neoplastic progression in ulcerative colitis: histology, DNA content, and loss of a p53 allele.

Neoplastic progression in patients with chronic ulcerative colitis (UC) is characterized by the development of epithelial dysplasia, which is accompanied by genetic abnormalities that can be detected by flow cytometric and molecular biologic methods. Distribution of and correlation between histologic abnormalities, DNA content, and loss of heterozygosity for a p53 allele (p53 LOH) in the colons of nine UC patients were analyzed. Loss of a p53 allele was found in 85% (22/26) of biopsy specimens classified histologically as carcinoma, 63% (25/40) of biopsy specimens with high grade dysplasia, and 33% (7/21) of biopsy specimens with low grade dysplasia. Loss of heterozygosity for p53 was also found in 9% (5/57) of biopsy specimens indefinite for dysplasia and in 1/18 biopsy specimens negative for dysplasia, showing that this genetic change may occur early in the histological progression towards carcinoma. Aneuploid DNA contents were more common than p53 LOH in regions with negative, indefinite or low grade dysplastic histology; moreover, p53 LOH was detected only in aneuploid cells and not in diploid epithelium. Aneuploidy alone was not as specific a marker for the concomitant presence of dysplasia or carcinoma in a biopsy sample as aneuploidy combined with p53 LOH. These findings show that aneuploidy may precede both p53 LOH and epithelial dysplasia. Two UC patients' colons contained geographically separated clones of cells with different aneuploidies that also showed loss of different p53 alleles, suggesting that neoplasia may arise within different populations of cells in separate areas of the same colon.


In vivo effects of indomethacin on the activity of metal-containing enzymes.

1. Indomethacin injected subcutaneously at a single "ulcerogenic" dose decreased aminooxidase and leucine aminopeptidase activity and did not change alcohol dehydrogenase and ceruloplasmin activity. 2. Indomethacin administered at an oral "therapeutic" dose inhibited aminooxidase activity in small intestinal mucosa but not in liver and did not change leucine aminopeptidase activity in blood, liver and intestinal mucosa; it, however, increased alcohol dehydrogenase and ceruloplasmin activity. 3. The decreased activity of ceruloplasmin and alcohol dehydrogenase by metal deficiency increased after oral indomethacin treatment, reaching the control values when indomethacin was chelated with copper. 4. The results suggest the participation of endogenous metals in the indomethacin effect.


Absence of mitochondrial beta-adrenoceptors in guinea pig myocardium: evidence for tissue disparity.

1. Binding sites in guinea pig myocardial tissue labelled by (-)-[125I] cyanopindolol (CYP) were investigated using differential centrifugation and autoradiographic techniques. Autoradiographs of myocardial sections (0.1 microns) indicated (-)-[125I]CYP binding to sarcolemmal membrane. A low density of binding sites was observed to mitochondria. 2. Binding studies were performed in subcellular fractions. The density of binding sites in the mitochondrial fraction (36.1 +/- 9.4 fmol/mg protein) was less than 10% that in the sarcolemmal membrane (371.7 +/- 38.2 fmol/mg protein). The beta 1/beta 2-adrenoceptor subtype ratio in the mitochondrial fraction (83.3/16.7) was similar to that in the sarcolemmal fraction (87.1/12.9). 3. Ouabain (100 microM), in the presence of sodium azide (0.4 mM), inhibited a Na+K+ stimulated ATPase activity (1.0 +/- 0.2 mumol Pi/mg protein/hr reduction), indicating a low but significant level of sarcolemmal contamination of the mitochondrial fraction. 4. The study showed beta-adrenoceptors in guinea pig heart are located primarily on the sarcolemmal membrane of myocardium. No evidence was obtained for beta-adrenoceptors over mitochondria, as has been suggested in other tissues and species, but that this binding was to sarcolemmal inclusions in the mitochondrial fraction.


Alpha 1-adrenoceptor blocking activities of bevantolol hydrochloride(NC-1400) and labetalol in rat isolated thoracic aorta--do they distinguish between subtypes?

1. alpha 1-adrenoceptor blocking activity of bevantolol(NC-1400) was tested in the rat thoracic aorta, comparing with that of labetalol. 2. In alpha 1-adrenoceptor blocking activity, bevantolol(NC-1400) was 1/20th as potent as labetalol. 3. The pA2 values of bevantolol(NC-1400) and labetalol estimated in the rat thoracic aorta were compared with those in the rabbit thoracic aorta, which were reported by Takayanagi et al. [Takayanagi I., Kizawa Y., Iwasaki S. and Nakagoshi A. (1987) Gen. Pharmac. 18, 87-89]. 4. The pA2 values of bevantolol(NC-1400) and labetalol were approximately 1 order of magnitude higher in rat aorta than in rabbit aorta, suggesting that both the drugs distinguish between subtypes of alpha 1-adrenoceptors.


Influences of dopamine receptors on chewing behaviour in rats.

1. Intraperitoneal (i.p.) injection of different doses of pilocarpine induced purposeless chewing in rats. Physostigmine (i.p.), but not neostigmine (i.p.) also induced chewing behaviour. 2. Subcutaneous (s.c.) pretreatment of animals with the D-1 receptor blocker SCH 23390 decreased the number of chews induced by pilocarpine. 3. The D-2 dopamine antagonist sulpiride (i.p.) and anticholinergic atropine (i.p.) pretreatment also decreased the frequency of chews induced by the drug. 4. The response induced by pilocarpine (1 mg/kg i.p.) also was dose-dependently decreased in animals pretreated with apomorphine (0.25-1 mg/kg s.c.). 5. Administration of low doses of apomorphine (s.c.) also induced chewing, which was decreased with increasing the doses of the drug. 6. Chewing-induced by apomorphine was decreased by sulpiride or atropine and increased by SCH 23390 pretreatment. 7. Single administration of D-2 dopamine agonist bromocriptine also showed a slight but significant purposeless chewing, which was decreased by sulpiride pretreatment. 8. Single administration of D-2 agonist quinpirole, D-1 agonist SKF 38393 or D-1 antagonist SCH 23390, but not sulpiride caused a slight chewing. 9. It may be concluded that D-1 or D-2 activation exert opposite influences on chewing behaviour in rats, although to prove this effect more elucidation is needed.


CFU-S and haematopoietic microenvironment in mice after fractionated irradiation. A study on spleen colonies.

The paper is aimed at evaluating the quantity and quality of the haematopoietic stem cells, CFU-S, in the bone marrow and the functional effectiveness of the haematopoietic microenvironment of the spleen in two time intervals after repeated exposure of mice to doses of 0.5 Gy gamma-rays once a week (total doses of 12 and 24 Gy). After irradiation, bone marrow was cross-transplanted between fractionatedly irradiated and control mice. The parameter evaluated were numbers of spleen colonies classified into size categories. The data obtained provide evidence for a significant damage to the CFU-S, concerning both their number and proliferation ability, after both total doses used. The functional effectiveness of the haematopoietic microenvironment of the spleen was impaired only in bone marrow recipients receiving a transplant after having been exposed to a total dose of 24 Gy; this dose combined with subsequent pre-transplantation irradiation resulted in a marked suppression of cell production within the spleen colonies formed from a normal bone marrow on the spleens of fractionatedly irradiated mice.


TCP pilus biosynthesis in Vibrio cholerae O1: gene sequence of tcpC encoding an outer membrane lipoprotein.

The nucleotide sequence of the tcpC gene has been determined. It encodes a 53995-Da protein precursor with a signal sequence and cleavage site typical of a number of outer membrane lipoproteins, which are cleaved by the equivalent of signal peptidase II (Lsp) of Escherichia coli. The location of the tcpC gene is such that it is predicted to be translationally coupled to the 5' and 3' flanking genes, tcpY and tcpD, respectively, indicating that it forms part of an operon. Together with the lipoprotein signal sequence and the several hydrophobic domains it seems likely that TcpC is a surface-anchored trans-outer membrane lipoprotein.


Bacterial gamma-glutamyltranspeptidases: comparison of Escherichia coli and Pseudomonas gamma-glutamyltranspeptidase.

A high-level expression system for the Escherichia coli HB101 gamma-glutamyltranspeptidase (GGT) gene was constructed to obtain a sufficient amount of the enzyme for structural studies. About 300 mg of the enzyme was purified from 2 1 of culture broth. Both subunits were needed to reconstitute GGT activity. The E. coli GGT and the Pseudomonas GGT were compared with respect to catalytic properties and immunological relationships. Both enzymes showed different acceptor specificities. Relatively high immunocross-reactivity was observed between the small subunits of both enzymes by Western blot analysis using antibodies prepared against either enzyme.


Nonrandom distribution of chloroplast recombination events in Chlamydomonas reinhardtii: evidence for a hotspot and an adjacent cold region.

Intermolecular recombination of Chlamydomonas chloroplast genes has been analyzed in sexual crosses and following biolistic transformation. The pattern and position of specific exchange events within 15 kb of the 22-kb inverted repeat have been mapped with respect to known restriction fragment length polymorphism markers that distinguish the chloroplast genomes of the interfertile species Chlamydomonas reinhardtii and Chlamydomonas smithii. Recombinant progeny were selected from two- and three-factor crosses involving point mutations conferring herbicide (dr) and antibiotic resistance (er and spr) in the psbA, 23S and 16S ribosomal RNA genes, respectively. Exchange events were not randomly distributed over the 15-kb region, but were found to occur preferentially in a 0.7-kb sequence spanning the 3' end of the psbA gene and were much less common in an adjacent region of ca. 2.0 kb. These findings are corroborated by data showing that the dr mutation is unlinked genetically (3% recombination/kb) to the er and spr rRNA mutations, which are themselves linked and show ca. 1% recombination/kb. This discrepancy is significant since the dr-er and er-spr intervals are about the same length (ca. 7 kb). During chloroplast transformation, the 0.7-kb recombination hotspot also functions as a preferential site for exchange events leading to the integration of donor psbA gene sequences. The 0.7-kb hotspot region contains four classes of 18-37-bp direct repeats also found in other intergenic regions, but no open reading frame. Using deletion constructs in a chloroplast transformation assay, the hotspot was localized to a 500-bp region that lacks most of these repeats, which suggests that the repeats themselves are not responsible for the increased recombination frequency. Within this region, a 400-bp sequence is highly conserved between the chloroplast genomes of C. reinhardtii and C. smithii and includes several structural motifs characteristic of recombination hotspots in other systems.


Patterns of naturally occurring restriction map variation, dopa decarboxylase activity variation and linkage disequilibrium in the Ddc gene region of Drosophila melanogaster.

Forty-six second-chromosome lines of Drosophila melanogaster isolated from five natural populations were surveyed for restriction map variation in a 65-kb region surrounding the gene (Ddc) encoding dopa decarboxylase (DDC). Sixty-nine restriction sites were scored, 13 of which were polymorphic. Average heterozygosity per nucleotide was estimated to be 0.005. Eight large (0.7-5.0 kb) inserts, two small inserts (100 and 200 bp) and three small deletions (100-300 bp) were also observed across the 65-kb region. We see no evidence for a reduction in either nucleotide heterozygosity or insertion/deletion variation in the central 26-kb segment containing Ddc and a dense cluster of lethal complementation groups and transcripts (greater than or equal to 9 genes) compared to that seen in the adjacent regions (totaling 39 kb) in which only a single gene and transcript has been detected, or to that observed for other gene regions in D. melanogaster. The distribution of restriction site variation shows no significant departure from that expected under an equilibrium neutral model. However insertions and deletions show a significant departure from neutrality in that they are too rare in frequency, consistent with them being deleterious on average. Significant linkage disequilibrium among variants exists across much of the 65-kb region. Lower regional rates of recombination combined with the influence of polymorphic chromosomal inversions, rather than epistatic selection among genes in the dense cluster, probably are sufficient explanations for the creation and/or maintenance of the linkage disequilibrium observed in the Ddc region. We have also assayed adult DDC enzyme activity in these same lines. Twofold variation in activity among lines is observed within our sample. Significant associations are observed between level of DDC enzyme activity and restriction map variants. Surprisingly, one line with a 5.0-kb insert within an intron and one line with a 1.5-kb insert near the 5' end of Ddc each show normal adult DDC activities.


Genetic variability in a family of satellite DNAs from tilapia (Pisces: Cichlidae).

We have cloned and sequenced members of a family of satellite DNAs from three genera of the tilapiine tribe of fishes: Oreochromis, Sarotherodon, and Tilapia. The satellite DNAs, visualized as intensely staining bands following electrophoretic separation of EcoRI-digested genomic DNA, consist of three size variants differentially distributed in the various tilapiine species. The sizes of the monomers are approximately 237 bp (type I), 230 bp (type II), and 209 bp (type III). Several cloned monomers were sequenced from Oreochromis niloticus (type III), Oreochromis placidus (types I and II), Sarotherodon galilaeus (type I), Tilapia zillii (type I), and Tilapia rendalli (type I). Comparison of derived consensus sequences for the monomer units of the satellite DNAs revealed sequence identities within and between species that ranged from 89 to 96%. The type II and type III size variants appear to have arisen by deletions of 9 and 29 bp, respectively, within different regions of the type I satellite. Hybridization of a cloned monomer satellite from O. niloticus (type III) to PalI digests of genomic DNA from all three genera detected polymorphic, high molecular weight restriction fragments that produced fingerprint-like patterns. The complexity of these DNA fingerprints varied from one species to another, suggesting a markedly different genomic organization for these polymorphic satellite DNAs.


Comparative studies of Drosophila Antennapedia genes.

The Antennapedia (Antp) homeotic gene of Drosophila melanogaster controls cell fates and pattern formation in the epidermis, nervous system and mesoderm of thoracic segments. Its expression is controlled at the levels of transcription, alternative RNA splicing, polyadenylation and translation. Two nested Antp transcription units extend over 103 kb and produce sixteen different transcripts. We have compared the Antp genes of Drosophila virilis, Drosophila subobscura and D. melanogaster to determine which structural features are conserved and therefore may be important to the gene's function. The overall gene structures are similar. There are many conserved sequence blocks throughout the large introns, at least 15 kb upstream of the first promoter, and at least 3 kb downstream of the last polyadenylation site. Intron and exon sequence conservation around alternative splice sites indicates that alternative protein coding forms may also be conserved. Protein coding potential is perfectly conserved around the C-terminal homeodomain, well conserved in the N-terminal region, and more variable in the middle. The large size of the Antp gene may reflect a large number of control elements necessary for appropriate Antp protein expression. The conservation of transcript complexity suggests functional requirements for the different protein forms.


Recognition of the surface of a homeo domain protein.

Homeo domain proteins exhibit distinct biological functions with specificities that cannot be predicted by their sequence specificities for binding DNA. Recognition of the surface of the Oct-1 POU homeo domain provides a general model for the contribution of selective protein-protein interactions to the functional specificity of the homeo domain family of factors. The assembly of Oct-1 into a multiprotein complex on the herpes simplex virus alpha/IE enhancer is specified by the interactions of its homeo domain with ancillary factors. This complex (C1 complex) is composed of the viral alpha TIF protein (VP16), Oct-1, and one additional cellular component, the C1 factor. Variants of the Oct-1 POU homeo domain were generated by site-directed mutagenesis, which altered the residues predicted to form the exposed surface of the domain-DNA complex. Proteins with single amino acid substitutions on the surface of either helix 1 or 2 of the Oct-1 POU homeo domain had decreased abilities to form the C1 complex. The behavior of these mutants in a cooperative DNA-binding assay with alpha TIF suggested that the Oct-1 POU homeo domain is principally recognized by alpha TIF in the C1 complex. The preferential recognition of Oct-1 over the closely related Oct-2 protein is critically influenced by a single residue on the surface of helix 1 because the introduction of this residue into the Oct-2 POU homeo domain significantly enhanced its ability to form a C1 complex.


A single amino acid exchange transfers VP16-induced positive control from the Oct-1 to the Oct-2 homeo domain.

The selective association of the herpesvirus trans-activator VP16 with the human Oct-1 homeo domain is a model for differential positive transcriptional control by homeo domains. VP16 discriminates between the closely related homeo domains of Oct-1 and Oct-2 by distinguishing among their seven amino-acid differences; these differences lie on the surface that is thought to be accessible when the homeo domain is bound to DNA. Only two of these seven differences are recognized by VP16, one in each of the first two alpha-helices of the tri-alpha-helical homeo domain. The major determinant for selective association with VP16 in vitro and VP16-induced positive control in vivo is a single glutamic acid residue at position 22 in the first alpha-helix of the Oct-1 homeo domain, but the acidic properties of this residue are not critical for association with VP16 in vitro or in vivo, because it can be replaced by glutamine with little or no deleterious effect. Mere replacement of the single corresponding alanine residue in the Oct-2 homeo domain with the key glutamic acid residue is sufficient to confer on the Oct-2 homeo domain the ability to associate with VP16 in vitro and respond to VP16-induced positive control in vivo. Thus, the specificity of homeo domain positive control can be conferred by a single amino acid difference.


3'-UTR-dependent deadenylation by the yeast poly(A) nuclease.

Poly(A) tail removal is the first step in the degradation pathway for some mRNAs. The purified poly(A)-binding protein (PAB)-dependent poly(A) nuclease (PAN) from yeast removes mRNA poly(A) tails in vitro by a process similar to that observed in vivo. The exonucleolytic PAN degrades poly(A) and RNA bound by PAB, and can be activated by spermidine to degrade poly(A) in the absence of PAB. The shortening of the poly(A) tail down to 10-25 nucleotides and the terminal deadenylation of this short adenine tract are kinetically distinct reactions. Poly(A) shortening rates are stimulated by the yeast a-mating factor (MFA2) RNA 3' UTR sequence, and this occurs by switching PAN from a distributive to a more processive enzyme. Terminal deadenylation rates are also stimulated to different extents by various RNAs. Inversion of the MFA2 3' UTR sequence completely inhibits the terminal deadenylation reaction owing to the presence of an inhibitory element 70 nucleotides from the poly(A) tail. Other sequence elements inserted at a similar distance from the poly(A) tail also interfere with the reaction. These data suggest that the two phases of poly(A) degradation can be regulated by mRNA sequences, and they provide a mechanistic description of how this regulation could occur in vivo.


Synergistic activation of the insulin gene by a LIM-homeo domain protein and a basic helix-loop-helix protein: building a functional insulin minienhancer complex.

The distal portion of the rat insulin I gene 5'-flanking DNA contains two sequence elements, the Far and FLAT elements, that can function in combination, but not separately, as a beta-cell-specific transcriptional enhancer. We have isolated several cDNAs encoding proteins that bind to the FLAT element. Two of these cDNAs, cdx-3 and lmx-1, represent homeo box containing mRNAs with restricted patterns of expression. The protein encoded by lmx-1 also contains two amino-terminal cysteine/histidine-rich "LIM" domains. Both cdx-3 and lmx-1 can activate transcription of a Far/FLAT-linked gene when expressed in a normally non-insulin-producing fibroblast cell line. Furthermore, in fibroblasts expressing transfected beta-cell lmx-1, the addition of the Far-binding, basic helix-loop-helix protein shPan-1 (the hamster equivalent of human E47) causes a dramatic synergistic activation. ShPan-1 causes no activation in fibroblasts expressing transfected cdx-3 or the related LIM-homeodomain protein isl-1. Deletion of one or both of the LIM domains from the 5' end of the lmx-1 cDNA removes this synergistic interaction with shPan-1 without any loss of basal transcriptional activation. We conclude that beta-cell lmx-1 functions by binding to the FLAT element and interacting through the LIM-containing amino terminus with shPan-1 bound at the Far element. These proteins form the minimal components for a functional minienhancer complex.


Differential regulation of transcription preinitiation complex assembly by activator and repressor homeo domain proteins.

Different eukaryotic transcription factors can act through the same upstream binding site to differentially regulate target gene expression, but little is known of the underlying mechanisms. Here, we show that Ultrabithorax and even-skipped homeo domain proteins (UBX and EVE) of Drosophila melanogaster exert active and opposite effects on in vitro transcription when bound to a common site upstream of a core promoter. Both the activator UBX and the repressor EVE affect the extent but not the rate constant of preinitiation complex (preIC) formation. Both regulators act early in preIC assembly and are dispensable later. Assembling complexes become resistant to regulation by the bound proteins, but activation by UBX is restored upon ATP or dATP addition, and regulation by both proteins is restored after the addition of all four nucleoside triphosphates and transcription initiation. The results establish that upstream activators and repressors can function by fundamentally similar mechanisms, by differentially regulating an early step in preIC assembly, leading to formation of functionally distinct transcription complexes. A subsequent step renders mature complexes transiently refractory to activation and repression. Implications for the mechanism of transcription complex assembly and turnover and its regulation are discussed, including a new role for ATP in turnover.


Secretion of human blood coagulation factor XIIIa by the yeast Yarrowia lipolytica.

The industrial yeast, Yarrowia lipolytica, secretes high yields of an alkaline extracellular protease (AEP), which is synthesized as a preproprotein encoded by the XPR2 gene. We investigated the possibility of using this system for the secretion of human coagulation factor XIII subunit a (FXIIIa). This protein is naturally secreted in the plasma by an unknown, signal peptide-independent mechanism and has so far been found to be nonsecretable in yeast. We have designed six hybrid genes encoding fusion proteins between increasing portions of the AEP preprodomain and the precursor or mature forms of FXIIIa. All constructs directed translocation of the FXIIIa precursor into the endoplasmic reticulum. Transport of the translocated and core-glycosylated hybrid precursor to the Golgi apparatus appeared to be strongly rate limiting, and most of the precursors appeared to be partially proteolysed. One of these constructs directed the extracellular secretion of a low amount of hyperglycosylated FXIIIa. These results indicate that fusion to the yeast AEP signal peptide and dipeptide stretch allows FXIIIa to be translocated, albeit inefficiently, through the endoplasmic reticulum and to follow a classical secretory transit.


Effect of potentiation of cholinergic tone by pyridostigmine on the GH response to GHRH in elderly men.

The plasma GH response to GHRH (100 micrograms i.v.) was evaluated either alone or after pretreatment with pyridostigmine (120 mg orally 1 h prior to GHRH) in 9 younger men (age range: 22-39 years) and in 9 healthy elderly men (age range: 63-77 years). On a different occasion, subjects were tested with pyridostigmine alone. Basal concentrations of glucose, cortisol, androgens, estrogens, thyroid hormones and GH were similar in all subjects, whereas insulin-like growth factor was lower in elderly men. The GH response to GHRH was significantly lower in the older (mean peak was 6 times higher than baseline) than in the younger group (mean peak was 11.3 times higher than baseline). The pretreatment with pyridostigmine induced a striking increase in the GH response to GHRH in the younger subjects (mean peak was 26 times higher than baseline), whereas it produced only a slight increase in the GHRH-induced GH response in elderly men (mean peak was 8.7 times higher than baseline). When pyridostigmine was given alone, plasma GH levels rose significantly in both groups; however, the pyridostigmine-stimulated GH response was significantly higher in younger (mean peak was 6 times higher than baseline) than in older subjects (mean peak was 2.5 times higher than baseline). These data indicate that the cholinergic stimulatory regulation of GH release is reduced in elderly subjects. Since acetylcholine inhibits hypothalamic somatostatin release, the reduced cholinergic tone in elderly subjects may result in an increased somatostatinergic tone.


Use of cimetidine and other peptic ulcer drugs in Denmark 1977-1990 with analysis of the risk of gastric cancer among cimetidine users.

The prevalence of use of peptic ulcer drugs in the Danish population is described at two points in time using registrations of applications for reimbursement. In 1977-81, the prevalence of use of cimetidine was 0.4% in men and 0.2% in women. In 1989-90, the prevalence of use of peptic ulcer drugs was 1.3% in men and 1.2% in women. The increase in prevalence was apparent in all age groups, but most pronounced at relatively old age. The median age of users increased from 55 years in 1977-81 to 63 years in 1989-90. The data indicated that a third of those who used peptic ulcer drugs in 1977-81 also used these drugs in 1989-90, conditional on surviving this period. The probability of becoming a long term user was highest for those who were 50-69 years in 1977-81. The incidence of gastric cancer was investigated in the cohort of persons who used cimetidine in 1977-81. An excess risk of gastric cancer was apparent in the first years after start of cimetidine use. This is thought to reflect a selection bias. Significantly increased incidence was also observed in women seven years or longer after start of cimetidine use (RR = 4.7; 95% CI: 1.7-10.3). This estimate was, however, based on only six cases, and a similar pattern was not observed in men.


Effects of enteropathogenic Escherichia coli on microvillar membrane proteins during organ culture of rabbit intestinal mucosa.

This study examines the effects of an enteropathogenic Escherichia coli on microvillar membrane proteins during organ culture of rabbit ileal explants. Explants maintained with enteropathogenic E coli showed brush border effacement affecting approximately 50% of enterocytes, and where enteropathogenic E coli were closely adherent to the enterocyte surface microvilli were apparently being shed as vesicles. The microvillar membrane enzymes alkaline phosphatase, aminopeptidase N and alpha-glucosidase were released into the culture medium during organ culture, and this process was significantly enhanced by enteropathogenic E coli. This increased loss of microvillar membrane enzymes into the culture medium was associated with decreased tissue activities of microvillar membrane enzymes in enteropathogenic E coli infected ileal explants compared with control. For aminopeptidase N in particular, however, total enzyme activities in the tissue plus culture medium were increased comparing enteropathogenic E coli with control, suggesting that there might be an increase in the rate of synthesis of certain microvillar membrane proteins. Reorientating sucrose density gradient centrifugation of culture medium showed that alkaline phosphatase, aminopeptidase N and alpha-glucosidase were predominantly associated with particles of peak modal density 1.19 g/ml in both groups, confirming that enteropathogenic E coli accelerate release of microvillar membrane enzymes as vesicles. Analytical fractionation of ileal explants showed that enteropathogenic E coli resulted in a loss of microvillar membrane enzyme activities from the main brush border peak of modal density 1.21 g/ml present in controls. The density of the remaining smaller and lighter peak increased from 1.19 g/ml to 1.23 g/ml after homogenisation in digitonin, confirming association of these proteins with cholesterol containing membranes and not endoplasmic reticulum. These findings suggest that enteropathogenic E. coli accelerate the normal shedding of microvillar membrane proteins as vesicles, and may stimulate a compensatory increase in microvillar membrane protein synthesis.


Distribution of somatostatin-immunoreactive nerve fibres in Peyer's patches.

The distribution of somatostatin-immunoreactive nerve fibres in Peyer's patches of the cat was demonstrated by immunocytochemical techniques. A large number of immunoreactive nerve fibres was observed in the tela submucosa very close to the Peyer's patches. Some immunoreactive nerve cell bodies were also found in this layer. The immunoreactive nerve terminals ran around the margin of the follicles and only a few nerve fibres were observed in the centre of follicles. Electron-microscopic investigation showed that these immunoreactive nerve terminals were in very close contact with lymphocytes and plasma cells, where no Schwann cell sheath was interposed. The gap between the nerve processes and the lymphocytes and plasma cells was about 20-200 nm, and occasionally less. These results provide morphological evidence consistent with the view that somatostatin has a neuroimmunomodulatory action.


Glutamate metabolism, release, and quantal transmission at central excitatory synapses: implications for neural plasticity.

Glutamate is thought to act as a neurotransmitter at several excitatory synapses in the brain. Available knowledge reveals complex intercompartmental dynamics of glutamate, which is synthesized, accumulated and released by presynaptic elements, activates postsynaptic receptors, and is eventually re-uptaken and interconverted to glutamine by the participation of surrounding glial cells. The postsynaptic reactions to physiological release of glutamate during neurotransmission are considered in relation to the quantal approach, which is revealing unsuspected complexity in central synaptic mechanisms. This issue is particularly important in view of its implications in the study of long-term synaptic modifications.


Influence of multiple endocrine neoplasia type 1 on gastric endocrine cells in patients with the Zollinger-Ellison syndrome.

The influences of multiple endocrine neoplasia type 1 (MEN 1), hypergastrinaemia, age, and sex on gastric endocrine cell densities were studied in 48 patients with the Zollinger-Ellison syndrome of either the sporadic type (n = 31) or associated with MEN 1 (n = 17). The mean fundic argyrophil cell density was higher in women (p < 0.05). It showed no appreciable difference between young and old women but it declined with age in men. The mean argyrophil cell density, when adjusted for sex, was higher (+48.5%, p = 0.06) in patients with Zollinger-Ellison syndrome associated with MEN 1 than in those with sporadic type disease. This measurement was not significantly different between the two groups of patients when antisecretory treatments were considered. In patients with sporadic type disease, fundic argyrophil cells showed a normal pattern (16%) or diffuse (71%) or linear (13%) hyperplasia. In patients with MEN 1 diffuse and linear hyperplasia were of the same order (53% and 47%). Furthermore, fundic argyrophil endocrine tumours developed in five of 17-that is, 29.5% of patients with associated MEN 1 while none was seen in patients with sporadic type disease. These tumours showed an exclusive or prominent enterochromaffin like cell population. Antral gastrin and somatostatin cell densities and fasting serum gastrin concentrations were similar in the two groups of patients with Zollinger-Ellison syndrome. Whatever the underlying mechanism for carcinoidosis, the risk of developing fundic enterochromaffin like cell tumours in Zollinger-Ellison syndrome patients who present with MEN 1 is probably higher than was initially estimated and suggests that regular follow up of these patients is necessary.


Postmarketing surveillance of the safety of cimetidine: 10 year mortality report.

A total of 9928 cimetidine users were identified from prescriptions in four centres and followed for 10 years. The 'all-cause' mortality ratio fell from 1.9 in year 1 to 1.0 in years 8 to 10. Most of the early excess in mortality was attributable to cimetidine being given in the late stages of many diseases, often to counter adverse gastric effects of other drugs. Specific causes of mortality during years 5-10 of the study, were generally unremarkable. Significant increases in mortality ratios were apparent, however, for oesophageal cancer (years 5-7, 2.3; years 8-10, 1.9); lung cancer (years 5-7, 1.1; years 8-10, 1.7); diseases of the oesophagus, stomach, and duodenum (years 5-7, 3.3; years 8-10, 2.3); and chronic liver disease (years 5-7, 2.4; years 8-10, 3.3). None of these increases in mortality seems to be attributable to an adverse effect of cimetidine use. Data are also presented for mortality from diseases of the nervous system. Eight deaths (of which one was miscoded) were certified as being from motor neurone disease, representing a mortality ratio of 2.6 for years 2-10 of the study which is of borderline statistical significance. This study confirms that cimetidine is safe. Mortality from some diseases increased over the study period, but selection rather than any adverse effect of the drug is likely to be the explanation.


Inhibition by tiazofurin of inosine 5'-phosphate dehydrogenase (IMP DH) activity in extracts of ovarian carcinomas.

Cancer cells have an increased ability to synthesize GTP (guanosine triphosphate) because of increased activity of IMP DH (inosine 5'-phosphate dehydrogenase, EC 1.1.1.205). Because IMP DH activity is rate limiting for de novo biosynthesis of GTP, this enzyme was suggested as a sensitive target for chemotherapy. Tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide) is converted in the cells into the active metabolite, TAD, (thiazole-4-carboxamide adenine dinucleotide) which potently inhibits IMP DH activity. By adding TAD to tissue extracts one can determine the extent of inhibition of IMP DH. We applied the IMP DH assay method to extracts of normal ovaries (N = 11) and epithelial ovarian carcinomas (N = 10). The IMP DH activity (mean +/- SE) in ovarian carcinoma was 21.1 +/- 5.8 which was markedly higher than that observed in normal ovaries (2.9 +/- 0.7 nmol/hr/mg protein) (P < 0.05%). The inhibition by TAD of IMP DH activity in ovarian carcinomas (N = 4) was 81%. The results indicate that IMP DH activity is elevated sevenfold in ovarian carcinomas as compared to normal ovary and can be inhibited by exposure to tiazofurin (TAD). Similar high IMP DH activity and inhibition of the activity by TAD was observed in patients with chronic granulocytic leukemia in blast crisis among whom 70 to 80% remissions were reported. Since there is increased IMP DH activity in human ovarian carcinomas and in OVCAR-5 cells and tiazofurin and TAD inhibit IMP DH activity of these cells and the proliferation of human ovarian carcinoma xenografts in the mouse, tiazofurin may merit serious consideration for a Phase II trial for patients with recurrent/refractory epithelial ovarian carcinoma.


[Drug therapy of hypertrophic cardiomyopathy].

Hypertrophy of the myocardium occurring in hypertrophic cardiomyopathy (HCM) may affect different locations of the left ventricle. If the hypertrophy is sited in the region of the basal septum, obstruction of the left ventricular outflow tract (hypertrophic obstructive cardiomyopathy [HOCM]) occurs. characteristic of left ventricular function in HCM is hypercontractility and disordered diastolic relaxation. In the medical treatment of HCM, the calcium antagonists play a leading role. They improve relaxation and, through their negative inotropic effect, decrease the intraventricular gradient. Although beta-blockers reduce the gradient in outflow tract obstruction, they do not improve relaxation. In individual cases the use of diuretics and anti-arrhythmic agents may be necessary; in the case of atrial fibrillation the use of marcumar is recommended. In the event of dental treatment or invasive diagnostic procedures being necessary, prophylactic measures against endocarditis should be initiated.


Pharmacokinetics of glafenine and glafenic acid in patients with cirrhosis, compared to healthy volunteers.

Pharmacokinetic parameters were evaluated in 12 patients with alcoholic cirrhosis and 12 healthy volunteers after a single 400 mg oral dose of glafenine. Glafenine (G) and its major active metabolite glafenic acid (GA) were measured at regular intervals using a specific high performance liquid chromatographic method. Glafenine absorption was significantly delayed in cirrhotic patients (CP) (Tmax = 2.8 +/- 1.3 hvs 1.5 +/- 0.4 h, p less than 0.01) and was dramatically reduced in 3 patients. The large hepatic 'first pass' effect observed in healthy volunteers was markedly reduced in CP (ratio Cmax GA/Cmax G = 3.6 +/- 2.9 vs 18.9 +/- 9.8, p less than 0.001; ratio areas under the curves AUC GA/AUC G = 2.3 +/- 2.3 vs 18.2 +/- 11.2, p less than 0.001). The elimination half-life of G was prolonged in the CP (13.0 +/- 13.1 h vs 1.5 +/- 0.5 h, p less than 0.01). In CP, GA elimination half-life was increased (12.0 +/- 13.4 h vs 4.3 +/- 1.3 h, NS) but the difference did not reach statistical significance because of large variability. The significant rise of G plasma concentrations (Cmax = 2.2 +/- 2.1 mg/L vs 0.7 +/- 0.2 mg/L, p less than 0.05) and its longer half-life would lead to an accumulation if the usual dosage regimen was prescribed for CP and could result in nephrotoxicity. On the other hand, lower dosage would be ineffective because only GA is active and nephrotoxic. Hence, G should be given with great caution to CP.


Gene expression of pyrogenic cytokines in Hodgkin's disease lymph nodes.

Inflammatory cytokines released by either the neoplastic or reactive cells in Hodgkin's disease (HD) might mediate its peculiar clinical and histopathological features. We investigated by Northern blotting the gene expressions of the pyrogenic and inflammation-associated cytokines IL-1 alpha, IL-1 beta, TNF-alpha, TNF-beta (lymphotoxin) and IL-6 in 14 HD lymph nodes and studied their relation to systemic symptoms (B symptoms). Two ug of poly(A)+RNA from 14 HD lymph nodes (8 from symptomatic and 6 from asymptomatic patients, of different histological type and disease stage) were subjected to agarose electrophoresis, Northern blotted and hybridized to the various cytokine cDNA probes. The inflammatory cytokines were expressed very heterogenously in HD, even in lymph nodes with the same histological type and with similar stromal inflammatory reactions. IL-1 beta was increased about 2 to 10 times in 5 of 8 lymph nodes from patients with B symptoms, whereas the other cytokines were heterogenously expressed in both symptomatic and asymptomatic patients. Statistical analysis on densitometric values demonstrated that the difference in IL-1 beta expression between symptomatic and asymptomatic patients was significant (p less than 0.02). These results support the hypothesis of increased IL-1 levels in tumoral lymph nodes from symptomatic HD patients.


Carrier detection for prenatal diagnosis of hemophilia A in Italian families.

The results obtained from a comparative analysis between phenotypic bioassays as the ratio of factor VIII: C clotting activity to factor VIII: C-related antigen, and DNA haplotypes from RFLP's TaqI/St14 and BclI/F8A in 12 hemophilia A (HeA) families are described. DNA from HeA patients and related at-risk women has been analyzed by Southern blotting with two probes: the intragenic F8A and the extragenic St14. Factor VIII: C coagulant activity was measured by a one-stage method, and the Factor VIII-related antigen (FVIII: RAg) was assayed with bidimensional electrophoresis. Linkage analysis was performed with the LINKAGE computer programs; in particular, the risks of carrying HeA were calculated using the MLINK program. The observed heterozygosity for the flanking marker DXS 52 (TaqI/St14 RFLP) in combination with intragenic BclI/F8A polymorphism was 0.94. A statistically significant difference in frequency was detected at the DXS 52 locus (allele 4) in comparison with other Caucasian populations. Linkage analysis made it possible to combine the plasma bioassay values with the DNA marker haplotypes to determine the probability of carriership; 22 females at risk were investigated: 4 of them were identified as carriers and 18 were excluded. The risk of carrying hemophilia A for some women at risk in six families is reported. This study compares a classic method and DNA analysis in genetic counselling for hemophilia A. In some cases the two methods may give different results when identifying carriers in at-risk families. From these data it is possible to conclude that DNA analysis combined with the phenotypic bioassays for carrier detection gives more information that the two analyses taken separately.


Effect of nicotinic acid on plasma glucose concentration in normal individuals.

In order to assess the ability of nicotinic acid to decrease plasma glucose concentration, normal individuals were given continuous four hour infusions of either nicotinic acid (NA), somatostatin (SRIF), NA + SRIF, or 0.9% NaCl (Saline). Plasma non-esterified fatty acid (NEFA) concentration decreased to about one-fourth of the basal value in response to either NA or NA + SRIF, associated with statistically significant decreases in plasma glucose concentration. The ability of NA and NA + SRIF to decrease plasma glucose concentration was seen despite the fact that plasma insulin concentrations also fell significantly during both infusions. Although plasma glucose concentration fell significantly in response to both NA and NA + SRIF, the effect of NA + SRIF was approximately twice as great as that seen with NA alone. The augmented hypoglycaemic effect of NA + SRIF as compared to NA alone was associated with a concomitant fall in plasma glucagon concentration. In contrast, plasma glucose concentration did not change following Saline, and was actually higher than baseline after the infusion of SRIF alone. These results provide evidence that NA can lower plasma glucose concentration in normal volunteers, and suggests that this is mediated by the NA-associated decrease in plasma NEFA concentration.


Estimated central blood volume in cirrhosis: relationship to sympathetic nervous activity, beta-adrenergic blockade and atrial natriuretic factor.

The estimated central blood volume (i.e., blood volume in the heart cavities, lungs and central arterial tree) was determined by multiplying cardiac output by circulatory mean transit time in 19 patients with cirrhosis and compared with sympathetic nervous activity and circulating level of atrial natriuretic factor. Arterial norepinephrine level, an index of overall sympathetic nervous activity (3.08 nmol/L in patients vs. 1.36 nmol/L in controls; p < 0.01) was negatively correlated (r = -0.54, p < 0.01) with estimated central blood volume (mean = 23 ml/kg in patients vs. 27 ml/kg in controls; p < 0.05). Similarly, renal venous norepinephrine level (an index of renal sympathetic tone; 4.26 nmol/L in patients vs. 1.78 nmol/L in controls; p < 0.01) was inversely correlated with estimated central blood volume (r = -0.53, n = 18, p < 0.02). No significant correlation could be established between arterial atrial natriuretic factor level (8.9 pmol/L in patients vs. 9.6 pmol/L in controls; not significant) and estimated central blood volume. Hemodynamic values were subsequently modified with oral propranolol (80 mg). During beta-adrenergic blockade, the mean estimated central blood volume was not altered significantly, except in six patients who exhibited decreases in mean arterial blood pressure (85 to 69 mm Hg; n = 6) and decreases in mean estimated central blood volume (23.2 to 20.6 ml/kg; n = 6, p < 0.05). Slight increases were observed in mean right atrial pressure (2.2 to 3.7 mm Hg; n = 14, p < 0.05); this change was positively correlated with the change in estimated central blood volume (r = 0.44, n = 14, p = 0.06).(ABSTRACT TRUNCATED AT 250 WORDS)


Treatment of schizophrenia: current practice and future promise.

Studies published since 1988 describing the treatment of schizophrenia are reviewed. Antipsychotic agents play a dominant role in treatment, but, except for clozapine, no one drug has been proved more effective than any other. Ineffective medication and medication noncompliance may contribute to apparent treatment resistance. Used in conjunction with drug treatment, supportive psychotherapy that incorporates social skills training appears to be useful. Environmental interventions such as supervised housing and work with families appear to help patients function better in the community and avoid relapse. Trials of new antipsychotic agents and improved understanding of the neurochemistry of schizophrenia offer hope that improved therapies will become available.


Expression of p53 in human esophageal carcinoma: an immunohistochemical study with correlation to proliferating cell nuclear antigen expression.

Immunolocalization of the nuclear protein p53 tumor suppressor gene product is considered to be one of the best methods of detecting a mutated form of p53. We have studied p53 immunohistochemically by using monoclonal antibody pAb1801 in 15 cases of esophageal squamous cell carcinoma. Immunoreactive p53 was observed in the nuclei of tumor cells in 4% paraformaldehyde-fixed, frozen sections (12 of 15) and paraffin-embedded sections (11 of 15), but not in routinely processed (10% formalin-fixed) specimens. p53 expression was closely correlated with the malignant phenotype, including dysplasia. p53 was not observed in histologically normal mucosa, except in three cases in which scattered immunoreactivity was observed in parabasal and basal cells. Immunostaining of ki67 and proliferating cellular nuclear antigen on adjacent tissue sections revealed that p53 expression was strongly correlated with ki67 and proliferating cellular nuclear antigen in carcinoma and dysplastic cells, but not in normal mucosa, suggesting involvement of the mutated form of p53 in the cell cycle of malignant cells. Immunohistochemical patterns of p53 were not related significantly to clinicopathologic parameters in the cases examined. Therefore, p53 expression was strongly associated with the proliferation of carcinoma cells but not with that of normal cells in esophageal carcinoma.


No association between RFLPs at the porphobilinogen deaminase gene and schizophrenia.

An association study of restriction fragment length polymorphisms (RFLPs) in the porphobilinogen deaminase (PBGD) gene and schizophrenia was conducted. RFLPs detected by MspI, PstI, ApaLI and BstNI in intron 1 of the gene were studied in 49 patients and 79 controls. There were no significant differences between the groups in allele frequencies, genotype counts or haplotype distribution.


CpG hotspot causes second mutation in codon 408 of the phenylalanine hydroxylase gene.

A new mutation has been identified in exon 12 of the gene encoding phenylalanine hydroxylase at codon 408. The single base change from guanine to adenine changes the amino acid arginine to glutamine; thus, the mutation is defined as R408Q. This codon is the site of a mutation known to causes phenylketonuria. Both these mutations are located at the same CpG site.


Haplotype distribution and mutations at the PAH locus in Croatia.

Restriction fragment length polymorphism (RFLP) haplotypes and mutations at the phenylalanine hydroxylase (PAH) locus have been studied in 25 unrelated families from Croatia. The results of RFLP analysis demonstrated that 80% of the mutant alleles were associated with three haplotypes (1, 2 and 4). Eight mutations were detected on the background of six mutant haplotypes, comprising 68% of phenylketonuria (PKU) alleles in Croatia. The mutation in codon 408 was most frequent, as was the haplotype 2 allele with which it was associated. These data are in accordance with formerly published population genetic analyses at the PAH locus, and with studies revealing the molecular basis of the phenotypic heterogeneity of PKU. The codon 281 mutation was more frequent in Croatia than previously observed in other populations.