Clinical application of midtrimester non-invasive fetal RHD genotyping and identification of RHD variants in a mixed-ethnic population

OBJECTIVE

This study aims to assess the suitability of non-invasive prenatal RHD genotyping in non-immunized midtrimester pregnant women from a mixed ethnic population, to prevent unnecessary anti-D immunoglobulin prophylaxis and to identify RHD variants

METHODS

Rhesus D-negative pregnant women were offered fetal RHD genotyping at 24 gestational weeks. A total of 284 samples were tested for RHD status using multiplex rt-PCR amplification of exons 5 and 7 of the RHD gene and exons 6 and 10 in selected cases. Women carrying RHD-negative fetuses were counseled about their option to avoid routine antenatal anti-D immunoglobulin administration. Diagnostic accuracy of RHD genotyping was compared with postnatal Rhesus D serotyping.

RESULTS

A total of 184 positives (65%), 91 negatives (32%) and 7 cases (2.5%) compatibles with RHD variants were detected by RHD genotyping. No false negative results were found, and a single false positive was observed in a twin pregnancy. Genotyping was accepted when offered by 94% of women (284/302), and anti-D immunoglobulin was avoided in 95% (90/95) of RHD-negative fetuses.

CONCLUSIONS

Non-invasive routine antenatal RHD genotyping at 24 weeks of pregnancy is a highly accurate method, resulting in the avoidance of 95% of unnecessary administrations of anti-D immunoglobulin, with no false negative results.

Unlinked anonymous testing to estimate HIV prevalence among pregnant women in Catalonia, Spain, 1994 to 2009

This paper estimates the prevalence of human immunodeficiency virus (HIV) infections in women giving birth and women voluntarily terminating pregnancy over a period of sixteen years in Catalonia. Samples for HIV antibody detection were collected from the Neonatal Early Detection Programme for congenital metabolic diseases that covers 99% of infants born in Catalonia. The sampling method collected information of 50% of births every year and of all women attending three clinics for voluntary interruption of pregnancy. Using two sequential immunoassays we analysed unlinked anonymous blood spot samples from 549,689 newborns between 1994 and 2009 and from 31,904 women who voluntarily interrupted pregnancy between 1999 and 2006. HIV prevalence among women giving birth decreased from 3.2 per 1,000 in 1994 to 1.7 per 1,000 in 2009 (p<0.01) and the mean age of infected mothers increased from 26 years in 1994 to 32 years in 2009 (p=0.001). A decrease in HIV prevalence was also observed in women voluntarily terminating pregnancy, from 2.3 per 1,000 in 1999 to 1.0 per 1,000 in 2006 (p<0.01). In contrast, estimated HIV prevalence in mothers born outside Spain increased from 2.2 per 1,000 in 2002 to 3 per 1,000 in 2009 (p<0.01) and their average age increased from 27 years in 2003 to 31 years in 2009 (p<0.01).

Unlinked anonymous testing to estimate HIV prevalence among pregnant women in Catalonia, Spain, 1994 to 2009

This paper estimates the prevalence of human immunodeficiency virus (HIV) infections in women giving birth and women voluntarily terminating pregnancy over a period of sixteen years in Catalonia. Samples for HIV antibody detection were collected from the Neonatal Early Detection Programme for congenital metabolic diseases that covers 99% of infants born in Catalonia. The sampling method collected information of 50% of births every year and of all women attending three clinics for voluntary interruption of pregnancy. Using two sequential immunoassays we analysed unlinked anonymous blood spot samples from 549,689 newborns between 1994 and 2009 and from 31,904 women who voluntarily interrupted pregnancy between 1999 and 2006. HIV prevalence among women giving birth decreased from 3.2 per 1,000 in 1994 to 1.7 per 1,000 in 2009 (p<0.01) and the mean age of infected mothers increased from 26 years in 1994 to 32 years in 2009 (p=0.001). A decrease in HIV prevalence was also observed in women voluntarily terminating pregnancy, from 2.3 per 1,000 in 1999 to 1.0 per 1,000 in 2006 (p<0.01). In contrast, estimated HIV prevalence in mothers born outside Spain increased from 2.2 per 1,000 in 2002 to 3 per 1,000 in 2009 (p<0.01) and their average age increased from 27 years in 2003 to 31 years in 2009 (p<0.01).

Passive mechanical properties of cardiac tissues in heart hypertrophy during pregnancy

We evaluated changes in passive mechanical properties in cardiac tissues during rat pregnancy. Left and right ventricular free walls were dissected from hearts of nonpregnant, late-pregnant, and postpartum rats. Mechanical experiments in ventricular strips were done by stretch-release cycles using a step motor. The results show that during pregnancy, there is cardiac hypertrophy associated with (1) an increase in myocyte size, particularly of augmented myocyte length, (2) a decrease in passive tension developed by the myocardial walls, and (3) a decrease in both elastic modulus and hysteresis. All changes observed during rat pregnancy were reversed during postpartum. In conclusion, a heart with less ventricular rigidity could contribute to facilitating the ventricular filling in conditions of a greater circulating volume characteristic of pregnancy.

Value of NT-proBNP Determinations in the Follow-Up of Heart Transplantation

BACKGROUND

The N-terminal pro-brain natriuretic peptide (NT-proBNP) has been useful in the diagnosis and follow-up of heart failure. Whether it can be useful in the detection of acute rejection (AR) after heart transplantation (HT) has not been addressed. Our aim was to assess the prognostic value of NT-proBNP determinations after HT.

METHODS

We analyzed 137 endomyocardial biopsies (EMB) performed in 51 patients as assessment of AR and correlated them with NT-proBNP determinations. The value of NT-proBNP in the early follow-up of the novo HT was also assessed.

RESULTS

AR grade > or =3A was diagnosed in 10 of the 137 performed biopsies. There were no significant differences in NT-proBNP values between patients with or without AR (1047 +/- 629 versus 1886 +/- 3026 pg/mL, P = NS). There were 24 de novo HT, in these patients increased NT-proBNP levels showed an inverse significant correlation with time since HT (r = -0.40, P = .0001). During follow-up, 15 of the novo HT had a descending NT-proBNP curve over time, and in the remaining 9 (37%) a late increase of NT-proBNP values were observed. Those 9 patients had the following complications: AR > or =3A in 5 cases, 1 death, 2 required a permanent pacemaker, and in the last patient a significant EMB could not be obtained.

CONCLUSIONS

NT-proBNP values follow a descending curve early after HT. During the first months, a late increase of NT-proBNP value was associated with HT complications, with AR being the most frequent. Isolated increased NT-proBNP levels were not useful for the detection of AR. More studies are needed to establish the prognostic value of NT-proBNP after HT.

Effects of sprint and endurance training on passive stress-strain relation of fast- and slow-twitch skeletal muscle in Wistar rat

We investigated the effects of endurance and sprint training on the passive mechanical properties of fast-twitch (FT) and slow-twitch (ST) skeletal muscles. Eight-week-old male Wistar rats (n=18) were divided into three groups: control (C), sprint-trained (S) and endurance-trained (E). The trained animals exercised for 10 weeks on a treadmill. Under anaesthesia, Plantaris and Soleus muscles were deformed cyclically in vivo at 0.33 mm x s(-1) with length increments of 1 mm in successive cycles until rupture. The rupture of muscle occurs at belly. Stress-strain relation were constructed using the maximum stress and maximum strain in each cycle. The data were fitted to an S-shaped curve. The curve-fitting parameters for trained and untrained muscles showed significant statistical differences. Stress and strain at rupture and maximum deformation energy were statistically greater for trained ST muscles (both groups) than for the controls. The changes induced by the present training protocols were not significant in Plantaris. The above results suggest the plasticity of passive structure caused by activity-demands.

[Late effects of radiotherapy in children]

Although most pediatric tumors can be cured with lower doses of radiation than their adult counterparts, long-term radiation-induced complications and sequelae remain a major concern both in terms of frequency and intensity. Most of them have been extensively documented in the pre-chemotherapeutic era like those affecting bone, cartilage and soft tissue growth or CNS and endocrine glands. More recently the emphasis has been put on the apparent increasing incidence of reported second malignancies. This could have been favored by the chemo-radiation combinations used in most children but also has been made possible mainly by the extensive follow-up of the increasing cohort of cured children.

Prolonged pneumoperitoneum at 15 mmHg causes lactic acidosis

BACKGROUND

Acute increases in intraabdominal pressure (IAP) induce systemic and regional circulatory changes. Besides, mechanical compression on the capillary beds may decrease oxygen availability to the tissues. The purpose of this clinical study was to analyze the effects of increased IAP on acid-base disturbances and plasma lactate levels during prolonged carbon dioxide pneumoperitoneum.

METHODS

Twenty-eight patients undergoing laparoscopic sigmoidectomy were included in this study. Fourteen of them (group A) had IAP of 15 +/- 1 mmHg while the remaining 14 (group B) had IAP of 10 +/- 1 mmHg. The control group included six patients undergoing conventional sigmoidectomy.

RESULTS

A progressive significant increase in PaCO2 was observed in the laparoscopic groups (p < 0.01). Plasma lactate levels in group A significantly increased 90 min after insufflation (p < 0.05) and reached the highest value 1 h after deflation (9.9 +/- 1 vs 31.9 +/- 2.5 mg/dl, p < 0.005). Simultaneously, arterial pH decreased in all groups; however, at 1 h after surgery, it was significantly lower (p = 0.02) in group A. There was a significant correlation between acid concentration due to lactate and lactate concentration (GA: R2 = 0.717, p = 0.03; GB: R2 = 0.879, p = 0.006 and GC: R2 = 0.853, p = 0.008).

CONCLUSION

High IAP causes lactic acidic accumulation in patients undergoing prolonged laparoscopic procedures.

Electrostatic forces as a possible mechanism underlying skeletal muscle contraction

A possible mechanism is put forward to explain the sliding of thin filaments during muscle contraction. In our model, repulsion due to electrostatic forces is the mechanism which triggers crossbridges to cause the thin filaments to slide. The mechanism proposed could operate regardless of whether the myosin heads rotate or bend, although recent experimental evidence seems to confirm the latter action. In spite of its simplicity, the model prediction of the velocity of sliding of the thin filaments agrees well with experimental values from in vitro motility assays.

Local relapse and contralateral tumor rates in patients with breast cancer treated with conservative surgery and radiotherapy (Institut Gustave Roussy 1970-1982). IGR Breast Cancer Group

BACKGROUND

Breast conservation is now established treatment for patients with small breast cancers. The authors reviewed a large series of patients with long term follow-up who underwent conservative treatment. Clinical and pathologic factors were analyzed to identify patients at an increased risk of relapse in the breast (local relapse) or development of a contralateral tumor.

METHODS

Seven hundred fifty-seven patients with unilateral invasive breast cancer (T0-2, N0-1, M0) were treated conservatively (wide local excision and radiotherapy) at the Institut Gustave-Roussy between 1970 and 1982. The median follow-up was 9 years. The risk of local relapse or development of a contralateral tumor (as first event) was studied by univariate analysis for the main clinical, pathologic, and treatment factors. Those found to be significant were entered into a Cox proportional regression analysis.

RESULTS

Fifty-one patients relapsed in the treated breast (actuarial local relapse rates at 5 and 10 years were 5% and 8%, respectively) and 34 in the contralateral breast (actuarial contralateral tumor rates at 5 and 10 years were 3% and 6%, respectively). Multivariate analysis of the risk factors for local relapse showed that only age younger than 40 years (P < 0.02) or inadequate surgical excisioin (P < 0.02) were significant. No particular risk factors for contralateral tumor development were identified.

CONCLUSIONS

Overall, for most patients, the risk of local relapse or of developing a contralateral tumor was low. A small number of young patients with inadequately excised tumors are at higher risk of local relapse, need more meticulous surgery, and may merit higher dose radiotherapy.

Local relapse and contralateral tumor rates in patients with breast cancer treated with conservative surgery and radiotherapy (Institut Gustave Roussy 1970-1982). IGR Breast Cancer Group

BACKGROUND

Breast conservation is now established treatment for patients with small breast cancers. The authors reviewed a large series of patients with long term follow-up who underwent conservative treatment. Clinical and pathologic factors were analyzed to identify patients at an increased risk of relapse in the breast (local relapse) or development of a contralateral tumor.

METHODS

Seven hundred fifty-seven patients with unilateral invasive breast cancer (T0-2, N0-1, M0) were treated conservatively (wide local excision and radiotherapy) at the Institut Gustave-Roussy between 1970 and 1982. The median follow-up was 9 years. The risk of local relapse or development of a contralateral tumor (as first event) was studied by univariate analysis for the main clinical, pathologic, and treatment factors. Those found to be significant were entered into a Cox proportional regression analysis.

RESULTS

Fifty-one patients relapsed in the treated breast (actuarial local relapse rates at 5 and 10 years were 5% and 8%, respectively) and 34 in the contralateral breast (actuarial contralateral tumor rates at 5 and 10 years were 3% and 6%, respectively). Multivariate analysis of the risk factors for local relapse showed that only age younger than 40 years (P < 0.02) or inadequate surgical excisioin (P < 0.02) were significant. No particular risk factors for contralateral tumor development were identified.

CONCLUSIONS

Overall, for most patients, the risk of local relapse or of developing a contralateral tumor was low. A small number of young patients with inadequately excised tumors are at higher risk of local relapse, need more meticulous surgery, and may merit higher dose radiotherapy.

Sodium/calcium exchange in tonic skeletal muscle fibers of the frog

The Na/Ca exchange system was investigated by contractile response to alteration of the extracellular sodium concentration in tonic skeletal muscle fibers of the frog. Contractures were evoked when the extracellular sodium was reduced or withdrawn in the normal solution. This effect was not associated with membrane depolarizations. In the presence of d-tubocurarine, the amplitude and time course of sodium withdrawal contractures were modified, except when sodium was replaced by TEA. When external calcium was omitted from the solution, the tension of sodium withdrawal contracture was greatly reduced. This effect was reversible. These results suggest that Na/Ca exchange is present in the membrane of tonic skeletal muscle fibers of the frog. This conclusion is further supported by the effect of veratridine and strophantidin, which increase the tension of the low-sodium contractures.

Further analysis of the molecular jet hypothesis during muscle contraction

We analyse the Molecular Jet-hypothesis proposed by Morel & Bachouchi (1988, J. theor. Biol. 132, 83.). This hypothesis attempts to explain the movement of covaspheres that contain myosin heads attached to actin filaments. This movement occurs during muscle contraction. However, the hypothesis does not predict the velocity of covaspheres correctly. Therefore, we are studying additional aspects of the hypothesis.

Epidermoid carcinoma of the anal canal treatment results and prognostic variables in a series of 242 cases

From 1972 to 1985, 260 cases of anal canal epidermoid carcinoma were irradiated. Eighteen cases treated for palliation were excluded from the study; 242 (93%) were treated with curative intent. The sex ratio was 1/5.5; mean age was 66 years.

HISTOLOGY

60.3% were well differentiated epidermoid carcinoma; 31.0% moderately differentiated and 8.7%, cloacogenic cases. Staging: T1: 11.5%; T2: 16.1%; T3a: 17%; T3b: 33.5%; and T4: 21.9%. Abnormal inguinal nodes were present in 15.3% of cases. Crude overall survival (Kaplan-Meier) for the 242 cases is 86.4% at 1 year, 63.9% at 3 years, 51.2% at 5 years, and 30.8% at 10 years. Radiation therapy was the sole treatment for 193 cases. No chemotherapy was given. Patients were irradiated by external beam. They received a first course of X rays (mostly 18 MV, some 6 MV) 40 to 45 Gy (box technique) over 4 to 5 weeks in the pelvis. Age and size of tumor were considered when deciding on the target volume. After a rest period of 4 to 6 weeks, a second course of 15 to 20 Gy in 2 weeks was given through a perineal field by electron-beam of suitable energy. The mean total dose was 60.56 Gy and median was 62.5 Gy; the mean overall treatment duration was 85.3 days (median 82 days) and the mean Time Dose Factor including decay factor was 98.96. In this group, 5-year determinate survival was: T1-T2, 84.5%; T3a, 74.8%; T3b, 64.9%; T4, 58.9%. In 147/193 patients (76.2%) local control was achieved. The overall anal conservation rate was 62.6%. In 106 cases (55%), the anus had maintained normal function. The 5-year survival rate by N was 73.3% in the absence of inguinal nodes (169 cases) and 36.1% if such nodes were present. There was no significant difference in survival rate according to histological type. In the second group, receiving radiation therapy plus surgery, 33/49 cases (T3b-T4) were irradiated before surgery (median dose 40.5 Gy). Post operative radiation therapy was administered in 16 cases (T3b-T4) (median dose 49.6 Gy). The 5-year determinate survival is 53.2% for T3b and 79% for T4. According to the log-rank test, there was no significant difference between survival with radiation therapy alone and radiation therapy plus surgery. Multivariate analysis of the whole group indicated that T stage is the only predictive variable.(ABSTRACT TRUNCATED AT 400 WORDS)

[Pregnancy after treated breast cancer. Results of a case-control study]

Sixty-eight cases of pregnancy after carcinoma of the breast were collected during a survey conducted by the Société Française de Gynécologie: 27 patients had one or several pregnancies interrupted at an early stage; 41 patients had at least one uninterrupted pregnancy. The fate of these patients was compared to that of 136 controls similar in all respects, except for the absence of post-cancer pregnancy. There was no significant difference in survival curves: the 10-year survival rate in our 68 patients was 71% (90% in those with N- cancer; 71% in those with N+ cancer, with no significant difference between cases and controls in each group). The patients whose pregnancies were interrupted had the same prognosis as those who delivered at term. The survival of 14 patients who conceived within 6 months of the breast cancer treatment was not significantly different from that of the corresponding controls. Pregnancy after breast cancer does not seem to alter the prognosis of the disease. In women with good prognosis cancer, the survival rate is excellent whatever the delay between cancer and pregnancy, and women should not be discouraged from having children; in women with poor prognosis cancer (N+), the outcome is not modified by pregnancy, and it remains lethal in about 50% of cases.

Tobramycin and amikacin nephrotoxicity. Value of serum creatinine versus urinary concentration of beta-2-microglobulin

108 patients who received tobramycin or amikacin could be evaluated for nephrotoxicity in a prospective randomized trial. Both groups had similar illnesses, and causative agents, concurrent drug administration, ages, sex ratios, initial serum creatinine and aminoglycoside levels and total dose and duration of therapy. Using urinary concentration of beta 2 microglobulin (beta 2m) as a marker, nephrotoxicity was detected in 13 (22.4%) of 58 patients given tobramycin and 13 (26%) of 50 given amikacin (n.s.). Using serum creatinine as a marker, nephrotoxicity was detected in 3 (5.2%) of 58 patients given tobramycin and in 7 (14%) of 50 given amikacin (n.s.). The whole group of 108 patients was used to compare the usefulness of serum creatinine levels versus urinary concentration of beta 2m. An elevation of serum creatinine was detected in 10 of 108 patients (9.3%). In 5 of these 10 patients the beta 2m remained normal, suggesting a functional renal failure. In 21 of the 108 patients (19.4%) the beta 2m increased while the serum creatinine remained normal, suggesting an aminoglycoside nephrotoxicity which would have remained undetected if only serum creatinine had been measured. In the remaining patients (77 of the 108; 71.3%) serum creatinine and urinary concentration of beta 2m both remained normal throughout the treatment. In conclusion no statistically significant differences were found between tobramycin and amikacin nephrotoxicity. Urinary beta 2m is more sensitive than serum creatinine and furthermore it allows one to differentiate aminoglycoside nephrotoxicity from functional renal failure.

Comparison of the nephrotoxicity and auditory toxicity of tobramycin and amikacin

A total of 157 patients were treated with tobramycin or amikacin in a controlled prospective randomized trial. Dosages were adjusted to renal function according to a nomogram. Trough and peak aminoglycoside levels were available at the end of the trial. Of the above total, 113 recipients of nine or more doses of tobramycin or six or more doses of amikacin, without other apparent cause of renal failure, were evaluated for nephrotoxicity. Thirty-six patients were evaluated for auditory toxicity. The patients in groups evaluated for either nephrotoxicity or auditory toxicity were similar with respect to intensity and etiology of bacterial disease, concurrent exposure to other antimicrobial drugs, age and sex distribution, initial serum creatinine level, and total dose and duration of antimicrobial therapy. Nephrotoxicity of similar severity developed in 4 of 59 (6.8%) recipients of tobramycin and in 7 of 54 (13.1%) recipients of amikacin (P greater than 0.05). Mild auditory toxicity developed in 3 of 19 (15.7%) recipients of tobramycin and in 2 of 17 (11.7%) recipients of amikacin (P greater than 0.05). When patients with abnormally high mean trough or peak aminoglycoside levels were excluded from comparison, nephrotoxicity was 6.12 and 5.12% (P greater than 0.05) and auditory toxicity was 17.6 and 7.69% (P greater than 0.05) in the groups given tobramycin and amikacin, respectively. We conclude that the nephrotoxicity and auditory toxicity of amikacin and tobramycin are not significantly different and that such toxicities are indeed infrequent events when the dosages of these drugs are adjusted to hold blood levels within the safe boundaries suggested by the studies of others.

Effects of heparin and protamine on left ventricular performance in the dog

The effects of protamine on left ventricular (LV) function were measured under conditions of controlled heart rate and proximal aortic pressure in eight anaesthetized, heparinised dogs. Protamine 3 mg.kg-1 produced a 21% decrease in LV dP/dt max, a 43% decrease in cardiac output, a 47% decrease in stroke work and decreases in systolic and diastolic pressures (-16%, -19% respectively). Protamine 6 mg.kg-1 resulted in a 17% decrease in LV dP/dt max, a 26% decrease in cardiac output, a 50% decrease in LV stroke work and 25 and 30% decreases in systolic and diastolic pressures. These results show that an impairment of LV function plays an important part in the circulatory depression produced by protamine.

Depression of hypoxic pulmonary vasoconstriction in the dog by dopamine and isoprenaline

The effects of dopamine and isoprenaline on the pulmonary vasoconstrictor response to alveolar hypoxia were assessed by measuring the redistribution of blood flow between the lungs in response to unilateral hypoxia. Dose rates of dopamine 25 micrograms kg-1 min-1 and isoprenaline 0.25 micrograms kg-1 min-1 (which produced equal increments in thecontractile force of the heart in dogs) produced a similar degree of depression of they hypoxic vasoconstrictor response, whereas dopamine 2.5 micrograms kg-1 min-1 had little effect on the response PaO2 during unilateral hypoxia was inversely related to the blood flow through the hypoxic lung.

Preservation of the hypoxic pulmonary vasoconstrictor mechanism during methoxyflurane anaesthesia in the dog

The effect of methoxyflurane on the hypoxic pulmonary vasoconstrictor response in the dog lung was assessed by measuring the redistribution of pulmonary blood flow in response to two levels of unilateral alveolar hypoxia. Methoxyflurane 0.5% had no significant effect on the redistribution of blood flow resulting from the unilateral administration of oxygen 7% or nitrogen and there were no significant differences in PaO2 between the measurements made during unilateral hypoxia with methoxyflurane and those made during unilateral hypoxia in the control periods.