257

Total

DNA probe to detect Giardia lamblia

genomic

SIR,-Whereas the development of cloned DNA probes for the detection of parasites’ is difficult, total genomic DNA probes are simple to produce and may give comparable sensitivity and specificity when used under controlled hybridisation conditions. 2-4 We report a radiolabelled total genomic DNA probe to detect Giardia lamblia trophozoites and cysts which shows similar specificity and sensitivity to a cloned probe reported previously.5 The probe was prepared by purifying and radiolabelling total G lamblia genomic DNA, as described previously for Trypanosoma cruzi.3 Samples (extracted DNA, trophozoites, or cysts) were spotted directly onto a nylon filter, denatured in alkali, and covalently linked to the filter by ultraviolet illumination. Cysts were exposed to 1-7 mol/I guanidine thiocyanate for 25 minutes at room temperature before spotting, since this enhanced hybridisation significantly. Prehybridisation for 2-4 h at 45°C in a solution of 50% formamide, 6 x saline sodium citrate (SSC), 0-05 mol/I sodium phosphate buffer pH 66, 5 x Denhardt’s solution, and salmon sperm DNA, was followed by hybridisation with the denatured probe for 16-20 h at 42°C in a solution of 6 x SSC, 0-01 mol/I sodium phosphate buffer pH 66, 1 x Denhardt’s solution, 50% formamide, 10% dextran sulphate, and salmon sperm DNA. Unbound probe was removed by high stringency washes before autoradiography. Using this probe, we obtained a hybridisation signal with 10 ng of G lamblia DNA, 105 trophozoites, and 1()4 guanidine-thiocyanate-treated cysts (figure). This compares favourably with a sensitivity of about 105 cysts using a radiolabelled probe selected from a cloned Giardia DNA library.5 There was no cross-reaction with the closely related Trichomonas vaginalis or with Entamoeba histolytica (figure), or with Crithidia fasciculata or Leishmania donovani. Though the probe cross-hybridised with

05 µg of T cruzi DNA, this would not be a problem in practice, and at 50 µg the amount of mammalian DNA needed to give a signal was orders of magnitude greater than the amount of Giardia DNA. The microscopic detection of G lamblia cysts in faecal smears may be only about 50% successful,6 and cysts present in water may be missed at concentrations below 4000/1.7 Thus, DNA probes may offer advantages over traditional methods of detecting Giardia. With the introduction of non-isotopic labels we would advocate their wider use as diagnostic tools. Division of Communicable Diseases, St George’s Hospital Medical School, London SW17 ORE, UK

Department of Medical Protozoology, London School of Hygiene and Tropical Department of Pure & Applied Biology, Imperial College of Science, Technology & Medicine, London

D. J. M. LEWIS Medicine

E. L. GREEN

F. ASHALL

1. McManus DP, Simpson AJG. Identification of Echinococcus organisms using cloned DNA markers. Mol Biochem Parasitol 1985; 17: 171-78. 2. Greig S, Ashall F. Detection of South American trypanosomes in insects using total parasite DNA probes. Parasitol Today 1987; 3: 375-76. 3. Ashall F, Yip-Chuck DAM, Luquetti AA, Miles MA. Radiolabelled total parasite DNA probe specifically detects Trypanosoma cruzi in mammalian blood. J Clin Microbiol 1988; 26: 576-78. 4. Flisser A, Reid A, Garcia-Zepeda A, McManus DP. Specific detection of Taenia saginata eggs by DNA hybridisation. Lancet 1988; ii. 1429-30. 5. Butcher PD, Farthing MJG. DNA probes for the faecal diagnosis of Giardia lamblia infections in man. Biochem Soc Trans 1989; 17: 363-64. 6. Kamath KR, Murugasu R. A comparative study of four methods for detecting Giardia lamblia in children with diarrhoeal disease and malabsorption. Gastroenterology 1974; 66: 16-21. 7. Feachem RG, Bradley DJ, Garelick H, Mara DD. In: Sanitation & disease: health aspects of excreta and waste water management. London: John Wiley & Sons, 1983: 349-56.

Normal

development after exposure to mifepristone in early pregnancy

Results of hybridisation with the total genomic Giardia DNA

probe. 1 =Glamblia DNA 1.5 J.!g (A), 05 g (B), 0.1 J.!g (C), 10 ng (D), 1 ng (E), 2=vaginalis DNA 5 pg (A), 0 5 µg (B), 50 ng (C); 3=Ehistolytica trophozoites 6 x 105 (A), 6 x 10’ (B); 4=T cruzi DNA 5 µg (A), 0,5 µg (B), 50 ng (C), 5=rat DNA 5 wg (A), 0-5 pg (B), 50 ng (C); 6=G lamblia trophozoites 10. (A), 5x 105 (B), 105 (C), 10’ (D), 103 (E), 500 (F); 7 = G lamblia cysts 105 (A), 6x10" (B), 310" (C), 10"(D), 6x 103 (E)

SIR,-Mifepristone (RU38486), due to its ability to block the action of progesterone in the pregnant uterus, offers a novel approach to drug-induced termination of pregnancy.’ Given alone to terminate early pregnancy mifepristone is effective in about 80% of cases. The subsequent administration of subtherapeutic doses of a prostaglandin analogue increases efficacy to 95%. It can also be given alone as a cervical ripening agent before transcervical operative procedures. Mifepristone has teratogenic effects in the rabbit but not in other speciesand it may have been associated with a malformed fetus aborted in the second trimester after the mother took the drug to terminate an early pregnancy.3 We wish to report the outcome of the pregnancies of three women who decided to continue to term, despite having taken mifepristone during participation in one of two clinical trials. Cases 1 and 2 were recruited into a study of mifepristone and gemeprost in the termination of early pregnancy. Case 3 took part in a double-blind, placebo-controlled trial of the cervical-priming properties of mifepristone before surgical termination of pregnancy. All patients gave written informed consent. Case 1. A 21-year-old primigravida was given mifepristone at 8 weeks’ gestation. Before prostaglandin administration, the patient indicated that she did not wish to proceed with the termination. Throughout the pregnancy, ultrasound scans showed satisfactory fetal growth. The patient reported two episodes of light brown vaginal discharge. The pregnancy progressed satisfactorily, and the patient went into spontaneous labour at 40 weeks’ gestation and delivered a healthy boy weighing 4150 g. Postnatal examination of the infant revealed no abnormality and he continues to develop normally 15 months later. Case 2. A 31-year-old (para 2 + 0) was given mifepristone at 8 weeks’ gestation. Before administration of the prostaglandin she indicated that she did not wish to proceed with the termination. 2 days later the patient was admitted with vaginal bleeding and mild pelvic cramps. Bleeding settled after 3 days in hospital and ultrasound scan confirmed a viable pregnancy. Subsequent antental progress was uncomplicated. The patient was admitted in labour at 39 weeks’ gestation and delivered a healthy male infant weighing

258

3930 g. Postnatal examination of the infant revealed no abnormality and he continues to develop normally 9 months later. Case 3. A 22-year-old primigravida was referred for surgical termination of pregnancy at 9 weeks’ amenorrhoea. She received mifepristone but vomited one and a half hours later. The patient reported seeing tablets in the vomit. Subsequently, the patient decided to continue with her pregnancy. Apart from three short episodes of abdominal pain, for which no cause could be found, the pregnancy was uneventful. The patient went into spontaneous labour at 41 weeks and delivered a healthy female infant weighing 3585 g. Post partum the patient had an 800 ml blood loss, thought to be due mainly to a labial tear. Postnatal examination of the infant revealed no abnormality and she continues to develop well at 6 months. Although the number of cases reported is small, these initial findings suggest that, as with animal studies,2 human fetuses which have been exposed to mifepristone and which are not subsequently aborted continue to develop normally. B. H. LIM Department of Obstetrics and Gynaecology, D. A. R. LEES Inverness Raigmore Hospital, Department of Obstetrics and Gynaecology, University of Edinburgh Department of Obstetrics and

S. BJORNSSON

Gynaecology,

Royal Infirmary, Glasgow

C. B. LUNAN

Department of Obstetrics and Gynaecology, Northern General Hospital, Sheffield

M. R. COHN P. STEWART

Roussel Laboratories Ltd, Denham UB9 5HP, UK

A. DAVEY

1. Sakiz

E, Euvrard C, Baulieu EE. The antiprogesterone activity of RU38486, a contragestive agent in the human In: Labne F, Proulx L, eds. Endocrinology. Amsterdam: Elsevier, 1984. 2. Jost A. Animal reproduction-new data on the hormonal requirement of the pregnant rabbit; partial pregnancies and fetal anomalies resulting from treatment with a hormonal antagonist given at a sub-abortive dosage. CR Acad Sci III 1986; 7: 281-84. 3. Henrion R. RU486 abortions Nature 1989; 338: 110. 4. Deraedt R, Vanmer B, Fournex R. Toxicological study on RU486. In: Baulieu EE, Segal SJ, eds. The antiprogestin steroid RU486 and human fertility control. New York: Plenum, 1985. 5. Wolf JP, Chillik CF, Dubois C, Ulmann A, Baulieu EE, Hodgen GD. Tolerance of perinidatory primate embryos to RU486 exposure in vitro and m vivo. Contraception 1990; 41: 85-92.

Reduction of lymphorrhagia from ruptured thoracic duct by somatostatin

-

-

Serial monitoring of concentrations (in

Triglycerides

Protein

lymph losses and protein and triglyceride g/I).

During treatment with TPN and somatostatin no significant clinical or laboratory abnormalities were noted, except for a mild rise in blood sugar without glycosuria. This was controlled by adding insulin to the parenteral solution and was, we think, due to the TPN. The impressive fall in the volume of lymph lost, and in its protein content, accords with the known effects of somatostatin and suggests a further useful application of this agent.

SIR,-In January, 1989, a 65-year-old man presented with dysphonia. A hard, fixed 8 x 5cm swelling subsequently developed the left side of the neck. In June, 1989, a well-differentiated epidermoid carcinoma of the larynx with cervical lymph node metastasis was diagnosed. Chemotherapy with 5-fluorouracil produced a tumour regression of greater than 50%. In September, 1989, supraglottic laryngectomy was performed with radical clearance on the left side. On the second postoperative day a milky lymphorrhagia appeared from the drain site. A compression bandage was applied and the polymeric enteral diet was changed to peptides with 77 % lipids. Because the lymphorrhagia still increased (to 1200 ml in 24 h, with protein concentration of 23 g/1), enteral nutrition was replaced by total parenteral nutrition (TPN) with 2620 kcal, 16-8 g nitrogen, and 106 g fat. After three days of TPN the lymph was no longer milky, but the flow was still considerable (1000 ml in 24 h). A second operation was considered but the patient’s poor nutritional status prompted a trial of somatostatin. 1-4 This agent was administered via a peripheral vein as a continuous infusion at a dose of 250 ug/h. After 3 days of treatment lymph flow halved, and on day 5 it ceased. Triglyceride concentrations fell after the start of TPN but the volume of lymph did not; volume only diminished on treatment with somatostatin (fig). Protein loss remained high on TPN and fell when somatostatin was given. After 6 days the dosage was reduced slowly to avoid any rebound effect. Treatment with somatostatin lasted 12 days. TPN was continued for 20 days until tolerance for oral feedings was complete and caloric intake was adequate.

-1

JOSÉ I. ULÍBARRI

on

Department of Clinical Nutrition and Diet,

Hospital de la Princesa, 28006 Madrid, Spain

YOLANDA SANZ CONCEPCIÓN FUENTES ANTONIO MANCHA MATILDE ARAMENDIA SALUD SÁNCHEZ

V, Harris V, et al. Evidence for a role of splanchnic SST in the homeostasis of ingested nutrients. Endocrinology 1979; 104: 1705-08. 2. Nakabayashi H, et al. Effect of SST on the flow rate and triglyceride levels of thoracic duct lymph in normal and vagotomized dogs. Diabetes 1981; 30: 440-45. 3. Schusdziarra V. Role of somatostatin in nutrient regulation. Adv Exp Med Biol 1985; 188: 425-45. 4. Schusdziarra V, Rouiller D, Unger RH. Oral administration of SST reduces 1. Schusdziarra

plasma triglycerides, gastrin immunoreactivity. Life Sci 1979; 24: 1595-600.

postprandial

and

gut

glucagon-like-

Comparison of immunoscintigraphy and colloid scintigraphy of bone marrow SIR,-Scintigraphy of the bone marrow was introduced to detect haematogenous metastases or malignant lymphomas affecting the skeletal system when they are still confmed to the marrow space and when bone scans and plain radiographs are usually normal.1-3 We report a comparison of two marrow-seeking radiopharmaceuticals in bone-marrow scintigraphy. We used human serum albumin nanocolloid (NC), which is taken up by reticuloendothelial marrow cells, and a murine monoclonal

Normal development after exposure to mifepristone in early pregnancy.

257 Total DNA probe to detect Giardia lamblia genomic SIR,-Whereas the development of cloned DNA probes for the detection of parasites’ is difficu...
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