Frequent aneuploidy in primary human T cells after CRISPR-Cas9 cleavage

Multiple clinical trials of allogeneic T cell therapy use site-specific nucleases to disrupt T cell receptor (TCR) and other genes^1-6. In this study, using single-cell RNA sequencing, we investigated genome editing outcomes in primary human T cells transfected with CRISPR-Cas9 and guide RNAs targeting genes for TCR chains and programmed cell death protein 1. Four days after transfection, we found a loss of chromosome 14, harboring the TCRα locus, in up to 9% of the cells and a chromosome 14 gain in up to 1.4% of the cells. Chromosome 7, harboring the TCRβ locus, was truncated in 9.9% of the cells. Aberrations were validated using fluorescence in situ hybridization and digital droplet PCR. Aneuploidy was associated with reduced proliferation, induced p53 activation and cell death. However, at 11 days after transfection, 0.9% of T cells still had a chromosome 14 loss. Aneuploidy and chromosomal truncations are, thus, frequent outcomes of CRISPR-Cas9 cleavage that should be monitored and minimized in clinical protocols.

The impact of a nationwide hands-on workshop on the diagnostic rates and management of obstetrical anal sphincter Injuries in Israel

AIM

The aim was to evaluate the influence of a half day, hands-on, workshop on the detection and repair of obstetric anal sphincter injuries (OASIs).

METHOD

Starting in February 2011, hands-on workshops for the diagnosis and repair of OASIs were delivered by trained urogynaecologists in departments of tertiary medical centres in Israel. The structure of the hands-on workshop resembles the workshop organized at the International Urogynecological Association annual conferences. Participants included medical staff, midwives and surgical residents from each medical centre. We collected data regarding the rate of OASIs, 1 year before and 1 year following the workshop, in 11 medical centres. The study population was composed of parturients with the following inclusion criteria: singleton pregnancy, vertex presentation and vaginal delivery. Pre-viable preterm gestations (< 24 weeks), birth weight < 500 g, stillborn, and those with major congenital anomalies, multifoetal pregnancies, breech presentations and caesarean deliveries were excluded from the analysis.

RESULTS

In the reviewed centres, 70 663 (49.3%) women delivered prior to the workshop (pre-workshop group) and 72 616 (50.7%) women delivered following the workshop (post-workshop group). Third- or fourth-degree perineal tears occurred in 248 women (0.35%) before the workshop, and in 328 (0.45%) following the workshop, a significant increase of 28.7% (P = 0.002). The increase in diagnosis was significant also in women with third-degree tears alone, 226 women (0.32%) before the workshop and 298 (0.41%) following the workshop, an increase of 28.3% (P = 0.005).

CONCLUSION

The detection rate of OASIs has significantly increased following the hands-on workshop. The implementation of such programmes is crucial for increasing awareness and detection rates of OASI following vaginal deliveries.

Retinal vascular diameters in relation to physical activity in Danish children - The CHAMPS Eye Study

Our objective was to determine associations between retinal vascular caliber and physical activity (PA) in a school-based child cohort. In a prospective study, we created a childhood cumulative average PA-index using objectively measured PA (accelerometry) assessed at four periods between 2009 and 2015. Cumulative exposure to PA intensities was estimated. Cross-sectional examinations on biomarkers, anthropometry, and ophthalmological data including retinal fundus photographs were performed in 2015. Semi-automated measurements of retinal vascular diameters were performed and summarized into central retinal arteriolar and venular equivalents (CRAE, CRVE). We included 307 participants. Mean age in 2015 was 15.4 years (0.7). The mean CRAE and CRVE were 156.5 μm (2.8) and 217.6 μm (7.7), respectively. After adjusting for age, gender, and axial length, more time in PA was independently related to thinner retinal venules (β-coefficient = -1.25 μm/%, 95% confidence interval = -2.20, -0.30, P < .01). Sedentary time was associated with wider venules (P < .01). Furthermore, birthweight (β-coefficient = 0.56 μm/%, 95% confidence interval = 0.18, 0.95, P < .01) was associated with CRVE. Blood pressure was associated with thinner retinal arterioles (β-coefficient = -0.19 μm/mmHg, 95% confidence interval = -0.36, -0.01, P = .04). We concluded that children with higher PA in childhood had thinner retinal venular caliber. Our results suggest that PA during childhood positively impacts the retinal microcirculation and that retinal vascular analysis may be a possible assessment to detect microvascular impairments in children with an increased risk of future cardiovascular disease.

Genetic and environmental effects on myopia development and progression

This review aims at elucidating the interaction between genetic and environmental factors in the aetiology of primarily low myopia. Genetics greatly influence the growth of the eye, but the fine correlation between the components of refraction for the eye to become emmetrope is affected by environmental factors such as education, metabolism, physical activity, and outdoor activity.

Sellar hemangioblastoma mimicking a macroadenoma

PURPOSE

Hemangioblastomas (HGB) are slow growing benign vascular tumors that arise almost always from the cerebellum and the spinal cord. Supratentorial location is extremely rare with approximately 130 cases published to date. We present a case of a sellar hemangioblastoma.

CASE REPORT

An eleven year-old girl presented with a sellar and suprasellar tumor that seemed to be a macroadenoma. A transsphenoidal approach was attempted but excessive intraoperative bleeding made the resection not feasible. A second transcranial approach was successful in partially removing the lesion and decompressing the optic chiasm and the pituitary stalk. Pathological review revealed a seller hemangioblastoma. screening for Von Hippel Lindeau Syndrome was negative.

CONCLUSION

The preoperative diagnosis of HGB is extremely difficult in this case but would have been essential in order to choose the right surgical approach.

Feasibility of cetuximab given with a simplified schedule every 2 weeks in advanced colorectal cancer: a multicenter, retrospective analysis

Cetuximab was approved using a weekly schedule, alone or in combination with chemotherapy (CT). However, many CT regimens in metastatic colorectal cancer (CRC) are delivered every 2 weeks (q2wks). Preliminary data suggested that a simplified schedule using cetuximab q2wks, 500 mg/m² would be equivalent to the standard weekly administration. Medical data of all patients with advanced CRC who received cetuximab q2wks were retrospectively collected and checked for consistency by an independent monitor in 4 European centers. Ninety-one patients were treated between 2005 and 2007 when the K-RAS mutational status of tumors was not determined routinely. They received a median of 4 (0-5) previous drugs, including previous weekly cetuximab in 38.5% of patients. Cetuximab q2wks was associated with an irinotecan-based regimen in 85.7% of patients. The median number of cetuximab administrations was 6 (1-23). Skin toxicity was observed in 68.2% of evaluable patients (grade 3 in 15%). Only one grade 1 allergy was reported. In the 84 patients beyond first-line therapy, response rate was 29.3%. The median progression-free survival was 3.0 months (range 2.2-3.8), and median overall survival was 9.0 months (range 6.2-11.8). Cetuximab q2wks appears safe and effective in heavily pretreated patients and convenient in combination with q2wks CT schedules.

Myopia in humans: can progression be arrested?

The multiplicity of theories regarding the aetiology of myopia has led to numerous and partly contradictory methods of therapy. Interest has been focused on accommodation because of the established association between myopia and close work. In studies of drug treatment of myopia, the treatment is often reported to be effective but the lack of randomization and high drop-out rates make the results questionable. In the Soviet Union, scleral reinforcement is said to be highly successful. Bifocal spectacle lenses reduce the accommodative demand, but studies on the effect of bifocal lenses have shown widely varying results. Whether contact lenses are effective in the control of myopia is still uncertain. In a Danish prospective study on the effect of treatment with bifocal lenses and beta-blocker eye drops a lower rate of progression was found among children wearing bifocal lenses but the difference from the control group was too small to warrant the use of such lenses in every myopic child. The progression rate in the group treated with the beta-blocker timolol maleate was not different from that in the control group. There thus seems to be no simple way of stopping or reducing the progression of myopia. Epidemiological data indicate that the maximum incidences of myopia are associated with educational systems in which the demands on the ability of the child to learn are stringent. One might introduce the term 'ocular stress' but this is clearly difficult to define and even more difficult to measure.

Dexamethasone, high-dose cytarabine, and oxaliplatin (DHAOx) as salvage treatment for patients with initially refractory or relapsed non-Hodgkin's lymphoma

BACKGROUND

Dexamethasone. cytarabine (ara-C), and cisplatin (DHAP) can be used effectively to treat patients with non-Hodgkin's lymphoma (NHL). We hypothesized that substitution of cisplatin by oxaliplatin (L-OHP) could result in less toxicity and greater efficacy. L-OHP is active in patients with lymphoma. It produces mild myelosuppression and is devoid of renal toxicity. We report on a phase II study of dexamethasone, high-dose ara-C, and L-OHP (DHAOx) used to treat patients with NHL who were previously treated with chemotherapy.

PATIENTS AND METHODS

Fifteen patients were given DHAOx. They had failed to achieve a CR with initial chemotherapy or had recurrent disease. DHAOx consisted of dexamethasone, 40 mg/day (days 1 to 4): L-OHP, 130 mg/m2 (day 1); and ara-C, 2,000 mg/m2 every 12 h (day 2). Treatment was repeated every 21 days.

RESULTS

Patients received a median of four courses of DHAOx. Myelosuppression and transient sensory peripheral neuropathy were the most prominent toxic effects. Serum creatinine levels did not increase in patients with normal renal function, nor in patients who had renal impairment before DHAOx. The median follow-up time from the start of DHAOx treatment was 17 months. Eight patients (53%) achieved a CR, and three patients (20%) had a PR. Responses were achieved by patients with lymphomas of various histologies that included mainly the follicular subtype, and by patients with and without resistance to prior chemotherapy. None of the eight responders have relapsed from CR at 4+. 6+, 14+, 15+, 19+, 20+, 24+, and 24+ months. They had various types of therapy after DHAOx. Disappearance of molecular markers was observed in all four patients who achieved a CR and whose tumor cells carried molecular abnormalities.

CONCLUSION

DHAOx possesses characteristics of toxicity which compare favorably to those reported with DHAP, and it is useful as a salvage treatment for patients with NHL. Larger studies are required to establish the therapeutic potential of the regimen.

The development of myopia in Hong Kong children

PURPOSE

The purpose of this two and one-half year follow-up study is to evaluate the relationship between early academic activities and the development of myopia.

METHODS

128 children randomly selected from 51 pre-schools completed an education and vision assessment study. At the end of the period, the children were 8.5 years old. Data were collected on developmental performance in the areas of cognition, language, social, academic and motor skills. The prevalence of myopia, mean refraction and change of refraction over this period were described in terms of the gender, geographical areas, type of pre-schools and type of primary schools.

RESULTS

The prevalence of myopia shifted towards a higher proportion of myopia in all the above categories. The mean refraction at the initial visit was 0.5 D and became about -0.50 D at the follow-up visit. There was no difference in the changes of refraction in relation to the type of pre-school or primary school. The change of refraction was also not related to the educational scores. However, there was a statistically significant difference in the academic scores, in particular the reading scores, between the activity and conventional primary schools. There was also gender difference in language scores between the girls and the boys of the activity schools. There was no difference in all scores between the myopes and non-myopes.

CONCLUSION

The present study did not demonstrate a relationship between early academic activities and development of myopia. However, the higher reading scores and the slightly faster progression rate in the conventional schools may indicate an influence of the curriculum on the refractive development. A longer follow-up study may elucidate a clearer trend.

Cytotoxic synergism of methioninase in combination with 5-fluorouracil and folinic acid

Potentiation of the cytotoxic activity of 5-fluorouracil (FUra) by folinic acid (5-HCO-H4folate) is due to elevation of the methylene tetrahydrofolate (CH2-H4folate) level, which increases the stability of the ternary complex of thymidylate synthase (TS), fluorodeoxyuridine monophosphate, and CH2-H4folate that inactivates the TS. Methionine deprivation results in the production of tetrahydrofolate (H4folate) and, subsequently, CH2-H4folate from methyl tetrahydrofolate, as a consequence of the induction of methionine synthesis. We hypothesized that the efficacy of FUra could be augmented by the combination of high-concentration 5-HCO-H4folate and recombinant methioninase (rMETase), a methionine-cleaving enzyme. Studies in vitro were performed with the cell line CCRF-CEM. Cytotoxic synergism of FUra + rMETase and FUra + 5-HCO-H4folate + rMETase was demonstrated with the combination index throughout a broad concentration range of FUra and rMETase. A subcytotoxic concentration of rMETase reduced the IC50 of FUra by a factor of 3.6, and by a factor of 7.5, in the absence and in the presence of 5-HCO-H4folate, respectively. 5-HCO-H4folate increased the intracellular concentrations of CH2-H4folate and H4folate from their baseline levels. Concentrations of folates were not changed by exposure to rMETase. Levels of free TS in cells treated with FUra + 5-HCO-H4folate and with FUra + rMETase were lower than those in cells exposed to FUra alone. The decrease of TS was still more pronounced in cells treated with FUra + 5-HCO-H4folate + rMETase. The synergism described in this study will be a basis for further exploration of combinations of fluoropyrimidines, folates, and rMETase.

Real-time quantitation of bcr-abl transcripts in haematological malignancies

We have applied an automated real-time quantitative PCR assay using a double-labeled fluorogenic probe to detect t(9;22)-positive cells in haematological malignancies. The results are expressed as the ratio of chimeric bcr-abl transcripts on abl transcripts. Highly reproducible results were obtained for t(9;22)-positive K562 RNA. Ten copies of bcr-abl DNA from a recombinant KW-3 plasmid and one positive cell in 10(4) can be detected. Thirty-two patients with chronic myeloid leukaemia (CML), 25 with acute leukaemia, 12 with myelodysplastic syndromes and 7 with other myeloproliferative syndromes were tested. Follow-up data were obtained in bcr-abl positive cases. Results were compared with those of conventional nested RT-PCR and cytogenetics. Real-time quantitative RT-PCR values correlated well with both these methods. However, in some cases the only means of detecting early relapse or blastic transformation was to examine the kinetics of real-time quantitative RT-PCR. Thus, real-time quantitative RT-PCR appears suitable for the diagnosis and follow-up of patients with the t(9;22) translocation.

Retinal detachment after cataract extraction in myopic eyes

PURPOSE

To determine the incidence of retinal detachment (RD) after cataract extraction in people 40 years of age or older with axial myopia (i.e., axial length > or = 25.5 mm).

SETTING

Fifteen Danish eye clinics.

METHODS

Two hundred forty-five eyes had cataract extraction performed at 15 eye clinics; 237 eyes had extracapsular cataract extraction (ECCE) and 8 eyes, intracapsular cataract extraction (ICCE). Postoperative data were reported by the practicing ophthalmologists. Mean follow-up was 27 months (range 14 to 32 months).

RESULTS

Five RDs occurred in the 245 eyes (2.0%). Excluding the ICCE cases and the two cases of combined cornea transplantation and ECCE, RD occurred in 4 of the 235 eyes that had ECCE (1.7%). The incidence after ECCE with posterior chamber lens implantation was 1.4%. Complete postoperative status was reported on 158 eyes. Forty-eight eyes (30.4%) had a neodymium:YAG capsulotomy and 3 (6.0%) developed an RD 1, 3.5, and 21 months after the capsulotomy.

CONCLUSION

The RD incidence after ECCE with posterior chamber lens implantation was low but higher than that in unselected populations. The incidence increased after laser capsulotomy.

Long-term prognostic and predictive factors in 107 stage II/III breast cancer patients treated with anthracycline-based neoadjuvant chemotherapy

The heterogeneity of therapeutic modalities and eligibility criteria and the lack of long-term follow-up in most reports of neoadjuvant chemotherapy for breast cancer preclude us from drawing conclusions about its value in clinically relevant patient subgroups. The present study aims to identify predictive and prognostic factors in 107 non-inflammatory stage II/III breast cancer patients treated between November 1980 and October 1991 with an anthracycline-based induction regimen before locoregional surgery. Preoperative chemotherapy comprised 3-6 cycles of doxorubicin (pirarubicin after 1986), vindesine, cyclophosphamide and 5-fluorouracil. Type of subsequent surgery and adjuvant treatment were decided individually. In analysis of outcome, univariate comparisons of end points were made using the log-rank test, and significant (P < or = 0.05) pre- and post-therapeutic factors were incorporated in a Cox multivariate analysis. With a median follow-up of 81 months (range 32-164+ months), the median disease-free survival (DFS) is 90.5 months while median overall survival has not yet been reached. Cytoprognostic grade and histopathological response in both the primary and lymph nodes were independent covariates associated with locoregional relapse with or without DFS and overall survival. Eleven patients with pathological complete response remain free of disease with a 68-month median follow-up, while the 18 with residual microscopic disease on the specimen showed a 60% cumulative incidence of locoregional recurrence. Despite encouraging response rates based on clinical or radiological evaluation (87% or 70%), neither method showed any significant correlation with pathological response and failed to contribute prognostic information on patients' outcome. Pathological evaluation of antitumoral activity of primary chemotherapy remains a major source of prognostic information and might be used to select patients in need of additional adjuvant treatment.

Relationship between myopia and optical components--a study among Chinese Hong Kong student population

PURPOSE

To establish the prevalence and severity of myopia among the Chinese Hong Kong students and to study the relationship between myopia and optical components.

METHODS

One thousand and seventy-five freshmen of the 1993-1994 academic year in the Chinese University of Hong Kong underwent the eye examination including evaluation of refractive error, keratometry, and A-scan ultrasonic biometry. The data were analyzed with the SPSS/PC+4.01 statistical package.

RESULTS

The prevalence of myopia was 91.7% with the mean refraction being -4.00 +/- 2.64D in this young adult population. The statistical analyses demonstrated a significant correlation between refractive value and axial length of the globe (r = -0.78), vitreous length (r = -0.76), anterior chamber depth (r = -0.33), lens thickness (r = 0.13) and corneal curvature (r = 0.19).

CONCLUSION

The refractive status is mainly dependent on the axial length. In general, the higher the myopia was, the longer the eyeball, the deeper the anterior chamber, the steeper the cornea, and the thinner the lens would be.

A simple manual method of repositioning small bowel during pelvic irradiation

Small intestine is often unnecessarily irradiated during radiotherapy because it lies near tumor volumes and thus may be dose limiting. Repositioning of normal tissues can sometimes be accomplished by mechanical rather than invasive surgical techniques. At our institution, physical displacement of small bowel tissues was carried out on a population of patients with good result. Patients suffering from prostatic, cervical, and rectal carcinoma were treated using a custom built and padded block composed of rigid Styrofoam. The block, in most cases, successfully displaced significant amounts of healthy tissues from treatment fields. Maximum displacement of bowel was accomplished at the time of simulation using fluoroscopy and manual positioning of the device. The optimum displacement position and location of the Small Bowel Displacement Device (SBDD) were recorded by means of orthogonal radiographs. The device was affixed to a piece of mylar that had been previously scribed with an X and Y coordinate system, which could be used to permanently anchor the SBDD to its position of maximum displacement. Displacements of as much as 4.0 to 5.0 cm were noted on most patients. Patients generally tolerated the device well as long as they were able to lie prone. Patients with recent abdominal surgery were less likely to tolerate the SBDD, and omental slings or meshes generally precluded movement of the small bowel.

[Risk of cataract surgery in patients with myopia. A prospective Danish multicenter study with special reference to a complication]

A prospective Danish multicentre study was conducted to evaluate the incidence of retinal detachment after cataract extraction in myopic eyes (axial length, > or = 25.5 mm). Two hundred and forty-seven cataract extractions in myopic eyes were reported during a period of 13 months. Two hundred and forty-one eyes underwent extracapsular and six eyes intracapsular cataract extraction. The mean follow-up time for 158 eyes was seven months (ranging from 1-30 months). In five cases a retinal detachment was observed, one case was probably present preoperatively, this person had undergone intracapsular cataract extraction. The incidence of retinal detachment was thus 1.62-2.02% in the total material and 1.66% in eyes operated with extracapsular cataract extraction.

[Glaucoma blindness in Denmark]

The prevalence and the incidence of glaucoma blindness in Denmark was evaluated by examining all registration forms of persons > or = 50 years of age admitted to the Danish Association of the Blind (DAB) between 1955 and 1987 with glaucoma as main cause of blindness. In 1987, 6.7% of DAB-members > or = 50 years suffered from blindness caused at least partially by glaucoma, equivalent to an estimated prevalence of 45 per 100,000 of the Danish population > or = 50 years. The estimated annual incidence of blindness due to glaucoma was seven per 100,000 > or = 65 years, and in an equal number of patients glaucoma was a contributory cause of blindness. The incidence of glaucoma blindness was decreasing in the younger age groups (< 65 years) throughout the study period. Glaucoma blindness seems to occur at a later age now than earlier, leaving the patients blind for a shorter time. The proportion of glaucoma blindness in the glaucoma population was estimated to be 4-5%.

5-Fluorouracil combined with the [6S]-stereoisomer of folinic acid in high doses for treatment of patients with advanced colorectal carcinoma. A phase I-II study of two consecutive regimens

BACKGROUND

Potentiation of the antitumor activity of 5-fluorouracil (5-FU) by folinic acid has been demonstrated in patients with colorectal adenocarcinoma. Modulation is due to the interaction of thymidylate synthase (TS), fluorodeoxyuridylate (FdUMP), and methylene tetrahydrofolate (5,10-CH2-FH4), which leads to the formation of a stable ternary complex with concomitant enzyme inactivation. Folinic acid consists of a mixture of equal parts of two stereoisomers differing in chirality at the C6 carbon of the pteridine ring. Only the levorotatory [6S]-folinic acid is transformed into active folate cofactors. However, the [6R]-stereoisomer is not inert; it was shown to interfere with the [6S] form at the cellular level. The possibility of a deleterious effect of the unnatural stereoisomer on the modulation of 5-FU led us to carry out 2 consecutive phase I-II studies of 5-FU combined with the [6S]-stereoisomer of folinic acid given in high doses for treatment of patients with advanced colorectal carcinoma.

PATIENTS AND METHODS

Treatment comprised 5-FU by i.v. infusion for 2 hours (the initial dose was 350 mg/m2/d; it was incremented by 25 mg/m2/d until a maximal dose of 550 mg/m2/d) and [6S]-folinic acid (100 mg/m2/d by rapid i.v. injection in Regimen 1, and 100 mg/m2 by rapid i.v. injection followed by a 2-hour infusion of 250 mg/m2 in Regimen 2) for 5 days, every 21 days. Twenty-five pts and 27 pts were assessed in Regimen 1 and in Regimen 2, respectively. They had had no prior chemotherapy. The median follow-up time was 9 months and 15.5 months for patients treated with Regimen 1 and Regimen 2, respectively. For pts treated with Regimen 1, the response rate was 52% (CR, 12%; PR, 40%). The median time to disease progression was 9.2 months. The probability of survival at 12 months was 73%. For pts treated with Regimen 2, the response rate was 37% (CR, 7%; PR, 30%). The median time to disease progression was 8.9 months. The probability of survival at 12 months was 67%. Improvement in quality of life was achieved in most patients who had symptoms due to the tumor before the start of treatment. The dose-limiting toxic effects (WHO grades > or = 3) were diarrhea, dermatitis, and mucositis. One single episode of grade 4 diarrhea occurred. After injection according to the schema in Regimen 1, [6S]-folinic acid was rapidly cleared from plasma (mean t 1/2 alpha and t 1/2 beta of 7.2 and 126 minutes, respectively). The mean concentration of the [6S]-stereoisomer two hours after injection was 5.8 mmol/L. After a rapid i.v. injection of 100 mg/m2 followed by a 2-hour infusion of 250 mg/m2, the mean concentration of [6S]-folinic acid two hours after the injection was 57.5 mmol/L. Pharmacokinetic data suggests saturation of the metabolic conversion of [6S]-folinic acid when large doses are administered.

CONCLUSION

The [6S]-form of folinic acid potentiates the antitumor effect of 5-FU given concomitantly. However, increase of the daily dose of the folate did not result in a therapeutic improvement. The present results justify a more complete exploration of the pure active stereoisomer as a modulator of the fluoropyrimidines.

Vapreotide, a somatostatin analogue, in cryptosporidiosis and other AIDS-related diarrhoeal diseases

OBJECTIVE

To evaluate the efficacy and tolerance of vapreotide, a new somatostatin analogue, in the treatment of refractory AIDS-related diarrhoea.

DESIGN

An open, non-comparative pilot trial.

SETTING

The trial was conducted in 10 medical centres in France.

PATIENTS, PARTICIPANTS

Thirty-four AIDS patients with chronic diarrhoea unresponsive to conventional antidiarrhoeal therapy were enrolled. Cryptosporidiosis was diagnosed in 21 out of 30 evaluable patients. Mean number of stools prior to therapy was 10.1 +/- 4.9 per day (range, 3-20 stools per day).

INTERVENTION

After initial baseline studies, patients received subcutaneous vapreotide at escalating doses of 400 (23 patients) or 500 micrograms (seven patients), between two and six times daily.

MAIN OUTCOME MEASURES

Efficacy was assessed after 14 days of therapy, when it was found to be effective. Responders were offered the opportunity to continue receiving therapy.

RESULTS

Four patients demonstrated a complete response and 12 a partial response with greater than 50% reduction in daily stool emission. Fourteen patients did not respond to doses up to 2400 micrograms/day. Patients with conditions other than cryptosporidiosis had a significantly higher probability of response (P = 0.013), as did those with milder diarrhoea (less than 10 stools per day). Median duration of response was 1.5 months (range, 0.5-5 months); relapse occurred in five out of eight responders despite maintenance therapy. Toxicity was minimal.

CONCLUSIONS

We conclude that AIDS patients with diarrhoea not caused by Cryptosporidium may benefit from vapreotide therapy.

Two sibs with Wiedemann-Rautenstrauch syndrome: possibilities of prenatal diagnosis by ultrasound

A girl with Wiedemann-Rautenstrauch syndrome was born to a non-consanguineous couple. During the pregnancy, growth retardation particularly in the biparietal and abdominal diameters but not the femoral length was detected through serial ultrasound scans. When the woman became pregnant again, in spite of having been assessed as having a 25% risk of recurrence, the prenatal findings seen in her previous pregnancy led us to suggest sequential echography and a similar pattern of growth retardation was shown. After termination, the male fetus was found to be affected by Wiedemann-Rautenstrauch syndrome. This case shows that ultrasound examination can be a useful tool in the prenatal diagnosis of this rare, autosomal recessive syndrome.

Fluorouracil combined with the pure (6S)-stereoisomer of folinic acid in high doses for treatment of patients with advanced colorectal carcinoma: a phase I-II study

BACKGROUND

Potentiation of the antitumor activity of fluorouracil (5-FU) by folinic acid has been demonstrated in patients with colorectal adenocarcinoma. Modulation is due to the interaction of thymidylate synthase, fluorodeoxyuridine monophosphate, and methylene tetrahydrofolate, which leads to the formation of a stable ternary complex with concomitant enzyme inactivation. Folinic acid consists of a mixture of equal parts of two stereoisomers differing in chirality at the C-6 carbon of the pteridine ring. Only the levorotatory (6S)-stereoisomer of folinic acid is transformed into active folate cofactors. However, the (6R)-stereoisomer of folinic acid is not inert; it was shown to interfere with the (6S) form at the cellular level.

PURPOSE

The possibility of a deleterious effect of the unnatural stereoisomer on the modulation of 5-FU led us to carry out a phase I-II study of 5-FU combined with the (6S)-stereoisomer of folinic acid given in high doses for treatment of patients with advanced colorectal carcinoma. We also determined the plasma pharmacokinetics of folates after intravenous (IV) injection of (6S)-folinic acid at the dose used in this study.

METHODS

Treatment consisted of 5-FU (350-550 mg/m2 per day by IV infusion for 2 hours) and (6S)-folinic acid (100 mg/m2 per day by IV bolus injection) given for 5 consecutive days; the treatment was repeated every 21 days. Twenty-five patients with advanced colorectal carcinoma, who had had no prior chemotherapy, were evaluated for antitumor activity. The quantity of folates in plasma was measured using a microbiological assay.

RESULTS

The median follow-up time was 9 months (range, 3.5-15.2 months). The response rate was 52% (complete response, 12%; partial response, 40%). The median time to disease progression for responding patients was 9.2 months (range, 5.9-15+ months). The estimated probability of survival at 12 months was 73%. Palliative improvement in quality of life was achieved in most patients who had symptoms due to the tumor before the start of treatment. The dose-limiting toxic effects were grade 3 diarrhea, dermatitis, and oral mucositis. Grade 4 toxicity did not occur. Myeloid toxicity was minor. After IV injection, (6S)-folinic acid was rapidly cleared from plasma (mean half-lives: alpha = 7.2 minutes and beta = 126 minutes). The mean concentration of the unchanged compound 2 hours after injection was 5.8 mumol/L.

CONCLUSION

The (6S)-form of folinic acid potentiates the antitumor effect of 5-FU given concomitantly.

IMPLICATION

Our results justify a more complete exploration of the pure active stereoisomer as a modulator of the fluoropyrimidines.

Glaucoma blindness in Denmark

In order to evaluate the prevalence and the incidence of glaucoma blindness in Denmark, all registration forms of persons greater than or equal to 50 years of age at admission, admitted to the Danish Association of the Blind (DAB) between 1955 and 1987 with glaucoma as main cause of blindness, were examined. In 1987 6.7% of DAB-members greater than or equal to 50 years of age suffered from blindness caused at least partially by glaucoma, equivalent to an estimated prevalence of 45 per 100,000 of the Danish population greater than or equal to 50 years. The estimated annual incidence of blindness due to glaucoma was 7 per 100,000 greater than or equal to 65 years, and in an equal number of patients glaucoma was a contributory cause of blindness. The incidence of blindness due to glaucoma was decreasing in the young age groups (less than 65 years) throughout the study period. Glaucoma blindness seems to occur at a later age now than earlier, leaving the patients blind for a shorter time. This pattern may be explained by improved health services but could also be due to a change in the spontaneous course of glaucoma. The proportion of glaucoma blindness in the glaucoma population was estimated to be 4-5%.

Retinoic acid in mono- or combined differentiation therapy of myelodysplasia and acute promyelocytic leukemia

Myelodysplastic preleukemic syndromes (MDPS) and acute promyelocytic leukemia (APL) share a surprising in vivo sensitivity to the hormonally acting 13 cis or all trans retinoic acids (transRA). Here we show that transRA as a monotherapeutic agent induced a stable remission in APL at the third relapse. In MDPS, treatment with prednisone and 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25D3) 13 cis RA induced a long-lasting hematological remission. Initially both patients had an impaired BM microenvironment which regenerated on retinoid therapy as judged by reappearance of the Hematon fraction in the BM aspirates. Our preclinical experiments using long-term liquid BM cultures (LTBMC) indicated that several individual patterns of growth and differentiation responses can be induced by combinations of transRA, 1 alpha,25D3 and hemopoietic growth factors (HGFs). The biological responses may vary from complete clonal extinction to a significant growth stimulation of the leukemic blast cell populations. These results further support the importance of preclinical studies in selecting "good" responders for, and excluding "poor" responders from protocols using differentiation therapy.