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J Lucas

Publications and source records attributed to J Lucas.

At least 37 records · Page 2Linked to original sources
PubMed2000

Mapping of X chromosome inversion breakpoints [inv(X)(q11q28)] associated with FG syndrome: a second FG locus [FGS2]?

FG syndrome is an X-linked condition comprising mental retardation, congenital hypotonia, macrocephaly, distinctive facial changes, and constipation or anal malformations. In a linkage analysis, we mapped a major FG syndrome locus [FGS1] to Xq13, between loci DXS135 and DXS1066. The same data, however, clearly demonstrated genetic heterogeneity. Recently, we studied a French family in which an inversion [inv(X)(q12q28)] segregates with clinical symptoms of FG syndrome. This suggests that one of the breakpoints corresponds to a second FG syndrome locus [FGS2]. We report the results of fluorescence in situ hybridization analysis performed in this family using YACs and cosmids encompassing the Xq11q12 and Xq28 regions. Two YACs, one positive for the DXS1 locus at Xq11.2 and one positive for the color vision pigment genes and G6PD loci at Xq28, were found to cross the breakpoints, respectively. We postulate that a gene might be disrupted by one of the breakpoints.

Abnormalities, Multiple↗
PubMed2000

Mycobacterium genavense infection in two aged ferrets with conjunctival lesions.

Mycobacterium genavense infection was diagnosed in two adult ferrets. Disseminated mycobacteriosis was diagnosed in a castrated 5-year-old sable ferret with generalised peripheral lymph node enlargement and a proliferative lesion of the conjunctiva of the nictitating membrane. The diagnosis was based on characteristic cytology and sequence analysis of the 16S rRNA gene amplified using the polymerase chain reaction from fresh biopsy material. Therapy with rifampicin, clofazimine and clarithromycin probably cured the infection. An entire 4-year-old female ferret with conjunctival swelling, serous ocular discharge and swelling of the subcutaneous tissues of the nasal bridge was diagnosed as having M genavense infection on the basis of typical cytology, histopathology and sequence analysis of 16S rRNA amplicons from formalin-fixed paraffin-embedded tissue. This patient was treated successfully using rifampicin. Both ferrets subsequently died as a result of other disease conditions, 10 and 4 months following initiation of therapy, respectively. This is the first report documenting M genavense as a cause of disseminated mycobacterial disease in ferrets. Conjunctival involvement may be a feature of disseminated mycobacteriosis in the ferret. The possibility that these infections were the consequence of a ferret retrovirus infection should be considered further.

Animals↗
PubMed2000

Teething and tooth eruption in infants: A cohort study.

OBJECTIVE: Many symptoms are attributed to teething in infants. There is little evidence to support these beliefs, despite their implications for clinical management. We investigated relationships between tooth eruption, fever, and teething symptoms. METHODS: Prospective cohort study. PARTICIPANTS: Twenty-one children 6 to 24 months old attending 3 suburban long-day care centers >/=3 days/week. Measures. 1) Daily temperature recording and examination of alveolar ridges for tooth eruption (dental therapist). 2) Daily questionnaires-symptoms over preceding 24 hours (staff and parents independently). 3) Final questionnaire-beliefs/experiences related to teething (parents). Definitions. Eruption day-the first day a tooth could be seen or felt. Non-toothdays-more than 28 days clear of any eruption day. Toothdays-the 5 days preceding eruption days. RESULTS: Data were collected for 236 toothdays and 895 non-toothdays pertaining to 90 teeth. Child temperatures were similar on toothdays and non-toothdays (36.21 vs 36.18, paired t test). Logistic regression adjusted for age did not show an association between toothdays and temperature (odds ratio [OR] = 1.35, 95% confidence interval [CI] = 0.80, 2.27 for high fever; OR = 1.34, 95% CI = 0.48, 3.77 for low fever). Logistic regression models allowing for within-child cluster effects and age were fitted to daily staff and parent reports of mood, wellness/illness, drooling/dribbling, sleep, diarrhea, strong diapers, red cheeks, and rashes/flushing. Only parent-reported (but not staff-reported) loose stools were significantly associated with tooth eruption (OR = 1.86, 95% CI = 1. 26, 2.73). When the toothday definition was varied to 10 days preceding or 5 days surrounding tooth eruption, this single significant association was no longer apparent (OR = 1.42, 95% CI = 0.98, 2.05 and OR = 1.47, 95% CI = 0.97, 2.21, respectively). All parents retrospectively reported that their own children had suffered a range of teething symptoms. CONCLUSIONS: This study did not confirm the expected strong associations between tooth eruption and a range of teething symptoms in children 6 to 30 months old, although we cannot rule out the possibility that weak associations may exist (Type II error). These findings contrast with strong parent and professional beliefs to the contrary. Such beliefs may preclude optimal management of common patterns of illness and behavior in young children.teething, infants, symptoms, tooth eruption, illness.

Adult↗
PubMed2000

Poor perception of airway obstruction in children with asthma.

The aims of this study were to evaluate children's perception of asthma symptoms and to determine a clinically useful method for identifying poor patient perception of airway obstruction. Three methods were used to analyze the relationships among indices of lung function and perception of breathlessness in 35 children. Approximately half the children in our sample did not perceive either airway obstruction or bronchodilation. We propose that <20% improvement in visual analog scale scores post-bronchodilation may provide a simple index for identifying patients with poor perception of airway obstruction, who may be at risk for fatal or near-fatal asthma.

Adolescent↗
PubMed2000

The syndromic tooth--the aetiology, prevalence, presentation and evaluation of hypodontia in children with syndromes.

Hypodontia can provide significant challenges to the clinician in both diagnosis and management. It is important that each patient is assessed not only by the dental team but also has genetic counselling to determine whether the hypodontia is a stand-alone condition or is associated with other anomalies. The advances in the understanding of tooth development and genetic control of tooth morphology not only allows clinical research to broaden its understanding of tooth agenesis but provides a basis for the clinician to provide the optimum clinical care. This paper presents an overview of the aetiology of hypodontia and its relationship with different syndromes and also the importance of understanding growth and development in treatment planning.

Anodontia↗
PubMed1999

Paracentric inversion of the X chromosome [inv(X)(q12q28)] in familial FG syndrome.

FG syndrome is an X-linked incomplete recessive condition comprising mental retardation, congenital hypotonia, macrocephaly, a distinctive facial appearance, and constipation or anal malformations. Here, we report on a chromosome X inversion [inv(X)(q12q28)] in a boy with FG syndrome and in his mentally retarded maternal uncle, and we discuss the possible involvement of this paracentric inversion in the FG syndrome.

Abnormalities, Multiple↗
PubMed1999

Preclinical memory decline in cognitively normal apolipoprotein E-epsilon4 homozygotes.

OBJECTIVE: To determine, in a cross-sectional evaluation of nondemented individuals, if age-related memory decline is influenced by apolipoprotein E (apoE) genotype. BACKGROUND: The apoE-4 allele is an important risk factor for AD. PET in cognitively normal apoE-4 carriers (mean age, 56 years) shows reduced cerebral metabolism suggestive of very early AD that precedes clinically evident memory loss or MRI-based hippocampal atrophy. METHODS: Tests of immediate and delayed recall (primary outcome measures) and other neuropsychological measures (secondary outcome measures) were given to three genetically defined groups of cognitively normal individuals (age, 49 to 69 years) including apoE-4 homozygotes (n = 25), apoE-4 heterozygotes (n = 25, all epsilon3/4), and apoE-4 noncarriers (n = 50). Groups were matched for age, gender, and educational background. Cross-sectional comparisons between the genetic subgroups of the relationship between age and test score were performed for each neuropsychological measure. RESULTS: There were no intergroup differences in mean scores on any neuropsychological measure, but tests sensitive to immediate and delayed recall showed a significant negative correlation with age in the apoE-4 homozygote group relative to the noncarrier group. CONCLUSION: Consistent with previous neuropsychological studies of early AD, this cross-sectional study suggests that age-related memory decline occurs earlier in cognitively healthy apoE-4 homozygotes than in apoE-4 heterozygotes and noncarriers, and precedes clinically detectable AD.

Age Factors↗
PubMed1999

Retroversion of the acetabulum. A cause of hip pain.

We describe a little-known variety of hip dysplasia, termed 'acetabular retroversion', in which the alignment of the mouth of the acetabulum does not face the normal anterolateral direction, but inclines more posterolaterally. The condition may be part of a complex dysplasia or a single entity. Other than its retroversion, the acetabulum is sited normally on the side wall of the pelvis, and its articular surface is of normal extent and configuration. The retroverted orientation may give rise to problems of impingement between the femoral neck and anterior acetabular edge. We define the clinical and radiological parameters and discuss pathological changes which may occur in the untreated condition. A technique of management is proposed.

Acetabulum↗
PubMed1999

Lung resection for the treatment of severe localised bronchiectasis in cystic fibrosis patients.

BACKGROUND: A small proportion of cystic fibrosis patients develop severe localised bronchiectasis. When this persists despite maximal medical therapy it presents a difficult management problem. Lung transplantation cannot be justified. We report encouraging results in six patients with severe localised bronchiectasis and cystic fibrosis who underwent pulmonary resection. METHODS: Each child had severe localised bronchiectasis despite maximal medical therapy. Intensive preoperative toilet was instituted and pulmonary resection undertaken when lung function was optimal. RESULTS: There was a marked improvement in symptoms in every case. No significant long-standing morbidity was associated with the resection. There was no significant decrease in pulmonary function following resection. CONCLUSION: Pulmonary resection should be considered in the management of severe localised bronchiectasis unresponsive to maximal medical therapy in cystic fibrosis patients.

Bronchiectasis↗
PubMed1999

[Feasibility of the laparoscopic sub-urethral sling procedure].

OBJECTIVE: To evaluate the feasibility of the laparoscopic sling procedure, 44 patients 26 to 66 years old (average 45) with sphincter incompetence were included in this prospective series between 1993 and 1999. PATIENTS AND METHODS: Patient selection for a sling procedure was based on urodynamic findings (average closure pressure was 34 cm of water). The operative procedure is described. RESULTS: The follow up ranged from two to 66 months (average 27.6). Seven conversions into laparotomy had to be performed. 35 slings could be set successfully. Four of these slings had to be removed during the year following the procedure; two because of bladder neck erosion and two because of chronic bladder distension. The success rate of the 35 slings is 88.6%. The overall complication rate is 27% including five bladder injuries, 2 urether injuries and one hemorrhage. Ten of the twelve complications occurred in the 12 first patients and the complication rate decreased to 9% in the 32 last patients. Average hospital stay was 4 days. CONCLUSION: The laparoscopic sling procedure seems to be promising in the management of refractory urinary incontinence due to sphincter incompetence. But it is an advanced laparoscopic procedure for experienced laparoscopic surgeons, needing a long learning curve.

Adult↗
PubMed1998

Churg-Strauss syndrome associated with zafirlukast.

The leukotriene receptor antagonist zafirlukast (Accolate; Zeneca Pharmaceuticals; Wilmington, Del) recently was approved for use as maintenance therapy for persistent asthma. This new product has been well received due to convenient dosing and relatively few side effects. Based on initial success with this product, it is likely that similar compounds will be available for use in the near future. In this report, a case is described of a 47-year-old white man with moderate persistent asthma in whom Churg-Strauss syndrome developed while he was receiving zafirlukast therapy. Acute respiratory insufficiency, arthralgia, and prominent rash developed which required hospitalization. The patient's symptoms rapidly reversed following discontinuation of zafirlukast therapy and administration of systemic corticosteroids. Although the incidence of Churg-Strauss syndrome associated with zafirlukast therapy is rare, this case report illustrates steps that may be taken to diagnose quickly and treat this life-threatening condition should it occur.

Anti-Asthmatic Agents↗
PubMed1998

Cell cycle gene regulation in reversibly differentiated new human hepatoma cell lines.

Several novel differentiated cell lines have been derived from a human hepatocarcinoma named HBG. Analysis of their functional properties evidenced a gradual differentiation process as they became confluent and a remarkable stability of the whole quiescent population for at least 6 weeks. However, when replated at low density after several weeks of quiescence, the differentiated cells were able to rapidly reverse to active proliferation, accompanied by transient dedifferentiation. Demonstration that the differentiated hepatic cells were growth-arrested in G1 phase was provided by the increased number of cells with 2C DNA content and decreased expression of S-phase markers. Characteristic features of oncogenes and cell cycle genes were defined during the differentiation process: (a) a biphasic expression of c-myc, with the latter wave covering the quiescence period; (b) opposite kinetics of c-Ki-ras and of N-ras expression with a pattern of changes paralleling that of c-myc; and (c) a decrease of cyclin D1 protein expression and of the cyclin D1-associated kinase activity. The mechanisms by which quiescent differentiated cells might reinitiate active proliferation were analyzed by studying several genes involved in cell growth and death regulation. We found: (a) a point mutation and loss of the specific activity of the tumor suppressor gene p53 without alteration of the apoptotic response to transforming growth factor beta1; (b) a gradual decrease of retinoblastoma protein, which was constantly present, mainly in a hyperphosphorylated form; and (c) an increase of cyclin-dependent kinase inhibitor p27 expression in confluent differentiating cells, as expected, whereas, surprisingly, a disappearance of the p21 protein was observed in parallel. These data may reflect specific mechanisms of cell cycle regulation in liver parenchymal cells through which these cells can proceed to control their reversible differentiation program.

Animals↗
PubMed1997

Phased chest and abdominal compression-decompression. A new option for cardiopulmonary resuscitation.

BACKGROUND: We describe a new manual method of phased chest and abdominal compression-decompression with a Lifestick resuscitator for cardiopulmonary resuscitation (CPR). METHODS AND RESULTS: Ventricular fibrillation (VF) was induced in 20 domestic pigs. After either 5 or 7 minutes of untreated VF, either phased chest and abdominal compression-decompression (Lifestick resuscitator) or precordial compression was initiated. Defibrillation was attempted at 2 minutes after the start of CPR. For the animals in which VF was untreated for 7 minutes, epinephrine was administered in doses of 20 micrograms/kg at 2 minutes after start of CPR. The coronary perfusion pressure generated by the Lifestick resuscitator was more than twofold greater (P < .01) than that generated by conventional precordial compression. Of 5 control animals, none were resuscitated after 5 minutes of VF. However, each of 5 animals treated with the Lifestick resuscitator was resuscitated (P < .01) and survived after 48 hours (P < .01). When untreated VF was prolonged to 7 minutes and epinephrine was administered, only 2 of the 5 control animals were resuscitated, and none of them survived for more than 4 hours. However, each of the Lifestick-treated animals was resuscitated and survived for more than 48 hours (P < .01). CONCLUSIONS: Phased chest and abdominal compression-decompression substantially increased hemodynamic efficacy of CPR and outcome in terms of successful resuscitation, 48-hour survival, and cerebral recovery.

Abdomen↗
PubMed1997

Hepatic lesion characterization in cirrhosis: significance of arterial hypervascularity on dual-phase helical CT.

OBJECTIVE: Our goal was to evaluate the diagnostic significance of the presence and pattern of arterial hypervascularity in lesions detected on dual-phase helical CT in cirrhotic patients. MATERIALS AND METHODS: Fifty-eight lesions greater than 1 cm in size were prospectively identified in 26 patients with end-stage liver disease who had undergone dual-phase helical CT for preoperative liver transplantation evaluation. All 26 patients had diagnoses proven by histologic evaluation or by clinical criteria. All arterial phase scans were retrospectively reviewed and lesions were categorized for the presence and pattern of arterial hypervascularity. Radiologic findings were correlated with histopathologic data. RESULTS: Thirty-seven of the 58 lesions had hypervascular components on arterial phase scans. All 37 of these lesions were found to represent hepatocellular carcinoma (HCC) (positive predictive value, 100%). Of the 21 remaining hypovascular lesions, 17 were HCC and four were benign (positive predictive value, 81%). Of the nine patients in whom all lesions were hypovascular, six had HCC (positive predictive value, 66%). The value of the presence of arterial hypervascularity for diagnosing HCC was statistically significant (p < .05). However, the presence or absence of arterial hypervascularity and the specific enhancement pattern revealed by helical CT did not correlate with histologic grading. CONCLUSION: The presence of hypervascularity in hepatic masses found in cirrhotic patients is highly predictive of malignancy.

Adult↗