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C Chau

Publications and source records attributed to C Chau.

At least 37 records · Page 2Linked to original sources
PubMed1996

Locomotor capacities after complete and partial lesions of the spinal cord.

This paper first reviews some of the observations made on the locomotor capabilities of several animal species with a special emphasis on cats and including primates and man after complete spinal lesions. We show that animals can perform well-coordinated walking movements of the hindlimbs when they are placed on a treadmill belt and this locomotion is also adaptable to speed and perturbations. Cats with partial spinal lesions of the ventral and ventrolateral parts of the cord can perform voluntary quadrupedal locomotion overground or on the treadmill albeit with deficits in weight support and interlimb coordination. We also show that some drugs such as clonidine (an alpha-2 noradrenergic agonist) can be used to trigger locomotion in early-spinal cats and discuss the effects of various neurotransmitter systems on the expression of the locomotor pattern in both complete and partial spinal cats. It is concluded that a pharmacological approach could be used, in combination with other approaches, such as locomotor training and functional electrical stimulation, to improve locomotor functions after spinal cord injuries in humans.

Animals↗
PubMed1996

Placental cord insertion visualization with prenatal ultrasonography.

Color Doppler and gray scale sonography can be used prenatally to identify the location of the cord insertion into the placenta. The purposes of this paper were to (1) relate sonographic identification of placental cord insertion with placental pathology; (2) evaluate the possibility that a marginal cord insertion may evolve into a velamentous cord insertion; and (3) determine the frequency and factors affecting sonographic visualization of cord insertion. Our results show that the sonographic assessment of cord insertion correlated with the pathologic outcome in 83% (106 of 128) of singleton pregnancies and at least one of the fetuses in 72% (8 of 11) of twin or triplet pregnancies. Although the sensitivity for identification of an abnormal cord insertion was low (42%), the specificity was high (95%). Our data suggest that marginal cord insertion evolved into velamentous cord insertion in one singleton and one twin. Our results showed that cord insertion was visualized in 54% of fetuses scanned in a routine clinical practice. Cord insertion visualization was possible at all gestational ages, although it was more difficult at later gestational ages. In conclusion, this study provides evidence that (1) ultrasonography (either gray scale or color Doppler) is useful in identifying normal, marginal, and velamentous cord insertion; (2) marginal cord insertion may evolve into velamentous cord insertion as pregnancy progresses; (3) in clinical practice the cord insertion site was visualized in just over half of the cases, and (4) prenatal identification of marginal and velamentous cord insertion potentially may be useful for planning obstetrical management.

Female↗
PubMed1993

In vivo MRI of the fetal brain.

We report MRI of the brain in 45 fetuses; the findings were confirmed by pathological examination or postnatal neuroradiological studies. MRI necessitates medication to eliminate fetal motion; curare was injected into the umbilical cord, and MRI is therefore limited to cases in which umbilical cord puncture is indicated. T1-weighted images were obtained in axial, sagittal and coronal planes; the last of these were generally as the most useful as regards morphology. We demonstrated cerebral malformations (n = 13), brain haemorrhage (n = 1), a facial angioma (n = 1), a facial mass (n = 1), hydrocephalus (n = 5), unilateral ventricular enlargement (n = 1), atrophy (n = 4), a porencephalic cyst (n = 1) and normal appearances of the brain in 18 cases. Twenty-two of the fetuses were born alive, and the clinical and/or neuroradiological examination confirmed the antenatal findings. The diagnosis was also confirmed in 8 cases in which a neuropathological examination was possible.

Agenesis of Corpus Callosum↗
PubMed1993

Noradrenergic agonists and locomotor training affect locomotor recovery after cord transection in adult cats.

In one series of experiments, the effects of noradrenergic, serotonergic, and dopaminergic precursors and agonists on the initiation of locomotion were investigated within the first week after complete spinalization at +13 in five adult cats. In addition, the effects of clonidine and daily locomotor training were investigated during the first week after transection in another cat. The electromyographic (EMG) activity of vastus lateralis (VL) and semitendinosus (St) was recorded bilaterally through percutaneously implanted copper wires in all cats. The movement of the hindlimbs on the treadmill was also simultaneously videorecorded before and after the injection of drugs. Without drug injection, strong and sustained perineal or abdominal stimulation did not induce any prolonged episodes of coordinated stepping on the treadmill during the first week after spinalization. St often had sustained activity, in contrast to VL, in which minimal or no activity was present. Injection of apomorphine (0.3 to 0.5 mg/kg, n = 3), a dopaminergic agonist, or DL-5-HTP (50 mg/kg, n = 2), a serotonergic precursor, failed to induce locomotion at such an early stage after spinalization. In contrast, injection of either L-dopa (50-60 mg/kg, n = 2), a noradrenergic precursor, or clonidine (150 micrograms/kg, n = 2), a noradrenergic agonist, induced locomotion on the treadmill. The animal demonstrated bilateral foot placement on the soles and complete weight support of the hindquarters. The spinal cat could follow the treadmill speed up to 0.80 ms-1. However, these effects disappeared when the NA drugs were tapered off.(ABSTRACT TRUNCATED AT 250 WORDS)

5-Hydroxytryptophan↗
PubMed1993

[Fetal supraventricular tachycardia. Management].

We report two cases of fetal supraventricular tachycardia with hydrops fetalis. The transplacental therapy with digoxin, sotalol and amiodarone, using combination of both of this drugs, has given in one case a partial conversion, total in the second case. Ultrasounds allow diagnosis of SVT, evaluate the gravity when it is associated with fetal hydrops secondary to a congestive heart failure, research a cause and follow the evolution during the treatment. The treatment must begin when diagnosis of SVT is done, by digoxin; other drugs as sotalol, amiodarone or flecainide acetate are described and also direct fetal therapy by intramuscular or into the umbilical vein injections.

Adrenergic beta-Antagonists↗
PubMed1992

[Contribution of Doppler in fetal prognosis].

Uteroplacental and cerebral artery velocimetry is a predictive factor in the outcome of many high-risk pregnancies. Positive predictive value is good for intrauterine growth retardation (complications due to preeclampsia, diabetes or twin pregnancy). Velocimetry is also a predictor of adverse outcome in small for gestational age fetuses and for oligohydramnios but not for anemic fetuses of isoimmune pregnancies or post-term pregnancies.

Cerebral Arteries↗
PubMed1991

Long-term metabolic function of pancreas transplants and influence of rejection episodes.

Pancreas grafts, when not rejected, can sustain an insulin-independent state in type I diabetic recipients for indefinite periods. To what extent the metabolic control achieved approaches that of normal individuals, the relationships between graft endocrine and exocrine function, the effect of reversible rejection episodes on subsequent graft function, and the correlation between the results of serial tests of graft function were determined by studies at 1 month, 1 year, and 2 years in a cohort of 39 recipients (29 females, 10 males; mean age (+/- SD), 33 +/- 5 years; mean duration of diabetes, 22 +/- 6 years) of bladder-drained pancreas transplants performed between November 1984 and December 1988. Fifteen patients received a pancreas transplant alone, 8 a pancreas after a kidney, and 16 a simultaneous pancreas/kidney transplant. Graft endocrine function was tested by a 24-hr metabolic profile of blood glucose levels before meals, at 1 and 2 hr after meals, and during the night (14 values in all), by intravenous and oral blood glucose tolerance tests, and by glycosylated hemoglobin levels (HA1 and HA1c). Graft exocrine function was assessed by urine amylase activity (U/hr). The results of the tests in the recipients were subjected to paired comparisons between timepoints and at each timepoint to the results of the same tests in 55 normal nondiabetic control individuals. The means of the mean 24-hr profile glucose (mg/dl) values were significantly lower (P less than 0.05) at 1 and 2 years posttransplant (116 +/- 27 and 115 +/- 15, respectively) than at 1 month (128 +/- 31) in the recipients, but the mean of the mean values in the normal controls (100 +/- 7) was even lower (P less than 0.05). Mean values of individual timepoints during the profile were significantly lower for 6 of the 14 values in the controls than in the recipients. The mean IVGTT K value of the normal controls (-1.9 +/- 0.4%) was significantly lower than the 1-month and 2-year values of the recipients (-1.5 +/- 0.5% and -1.3 +/- 0.6%, respectively), but the comparison with the 1-year value (-1.6 +/- 0.6%) was not significant. The mean glucose levels at zero minutes and between 120 and 300 min of the OGTTs were significantly lower at both 1 and 2 years than at 1 month in the recipients, and the values in the control group were also significantly lower than in the recipients at 1 month but not at 1 and 2 years.(ABSTRACT TRUNCATED AT 400 WORDS)

Blood Glucose↗
PubMed1991

Long-term quality of life after kidney transplantation in childhood.

Transplantation is the treatment of choice for children with end-stage renal disease. However, the long-term quality of life and socioprofessional outcome for those with successful transplants have not previously been reported. We studied these factors in patients transplanted when less than 18 years old who currently have greater than or equal to 10 years of graft function. A total of 57 questionnaires were sent out; 57 (100%) responded [24 female and 33 male patients; average (+/- SD) age at tx = 10 +/- 5 years (0.9-17.7); average f/u = 15.6 +/- 3 years (10-26); current age = 26 +/- 5 years (12-38); 26 had greater than 1 transplant]. Of the 57 respondents, 9 are less than 18 (all are in school); 48 are greater than or equal to 18 (7 in school, 37 employed, 4 unemployed); 12 are married, 1 engaged, and 2 divorced; and 9 have children. While in school, 43 (75%) had participated in sports, 37 (65%) in other extracurricular activities; 7 (12%) were A and 33 (58%) B students; 15 (26%) received awards or scholarships. For those working, the range of occupations is broad (average work week = 41 +/- 5 hr). Health-related absence from work has been nonexistent for 93%. Health is rated as good to excellent by 91% and fair by 9%. The future is regarded as hopeful or promising by 80%. Similarly, 89% are satisfied with life in general; 95% said health never or seldom interferes with family life; 95% feel health and drug side effects are of no or minor concern in sexual relationships. Only 3% feel health is a problem in maintaining a sexual relationship (41% are not sexually active). Only 4% stated that health often interferes with social life; 98% meet with friends on a regular basis; 76% are satisfied with personal relationships and 8% dissatisfied; 91% are satisfied with their ability to perform at work or school and 5% dissatisfied. Of note, 32% are dissatisfied with body appearance. Major concerns are short stature and brittle bones. Major suggestions include education/support groups to deal with teasing at school and peer problems. We conclude that transplanted children with long-term graft function have a favorable social and professional outcome. Overall, quality of life seems excellent.

Adolescent↗
PubMed1985

[Current aspects of fetomaternal immunizations].

The authors study all of the possible forms of foeto-maternal immunisation (ABO system, D antigen and other antigens). They present a general review of the course of allo-immunisations since the establishment of prophylaxis against anti-D allo-immunisations and they define the current situation.

ABO Blood-Group System↗
PubMed1980

Beta-haemolytic bacitracin sensitive strains of Streptococcus salivarius: a source of confusion with Streptococcus pyogenes in throat swab cultures.

Thirty strains of Streptococcus salivarius were beta-haemolytic when initially isolated from throat swabs and, because they were also bacitracin sensitive, they could be confused with the pathogenic Streptococcus pyogenes on primary culture plates. These strains were isolated form approximately 3000 throat swab cultures made in 6 mth, during which time 220 Lancefield group A organisms were also detected. Other features of these organisms, including loss of beta-haemolysis on subculture, penicillin resistance in half of the strains and ability to grow on MacConkey bile salt agar, are not shared by Strep. pyogenes, and their demonstration enables strains of the 2 species to be simply distinguished.

Bacitracin↗
PubMedDate not supplied

Congenital rapidly fatal form of nemaline myopathy with fetal hydrops and arthrogryposis. A case report and review.

A new lethal case of nemaline myopathy is reported. The diagnosis was made by postmortem muscle biopsy. The child died before his first day of life. This is one of the very rare cases of nemaline myopathy with severe antenatal ultrasonographic signs: fetal hydrops and arthrogryposis. In a review of the literature other cases of the congenital rapidly fatal form are found, some of them with clinical decrease of fetal movements but only few authors report ultrasonographic signs. The diagnostic, histopathogenic, genetic and evolutive aspects of this heterogeneous disorder are analyzed. This congenital nonprogressive myopathy is not as benign as previously thought and may be an etiology of the lethal form of arthrogryposis multiplex congenita. The existence of ultrasonographic antenatal signs seems to be a factor of poor prognosis. In spite of recent genetic discoveries, there is at present no specific antenatal diagnosis. Consequently, muscle biopsy in lethal cases is very important to allow a genetic counselling; however, in utero fetal biopsy has never been performed in such cases.

Adult↗