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D P Drake

Publications and source records attributed to D P Drake.

At least 37 records · Page 2Linked to original sources
PubMed1997

Disruption of local retinoid-mediated gene expression accompanies abnormal development in the mammalian olfactory pathway.

We have evaluated the role of retinoid signaling in the early development of the olfactory epithelium and olfactory bulb. When retinoid-mediated gene expression is blocked briefly in mouse embryos at midgestation with citral (a general alcohol dehydrogenase antagonist that is thought to interfere with retinoid synthesis), the spectrum of morphogenetic abnormalities includes disruption of olfactory pathway development. It is difficult, however, to assess the specificity of this pharmacological manipulation, insofar as it also compromises several other aspects of central nervous system development. In homozygous Pax6 mutant mice (small eye: Pax6(Sey-Neu)), there is a more discrete lesion to the olfactory pathway: The epithelium and bulb cannot be recognized at any time during development, whereas other forebrain subdivisions can still be recognized. This loss of the entire primary olfactory pathway is accompanied by a failure of retinoid-mediated gene expression limited to the frontonasal region and forebrain. Retinoid receptors are expressed in the forebrain of Pax6(Sey-Neu)/Pax6(Sey-Neu) embryos, and the mutant forebrain remains responsive to exogenous retinoic acid. However, in Pax6(Sey-Neu)/ Pax6(Sey-Neu) embryos, retinoic acid (RA) is not produced by the frontonasal mesenchyme, which normally provides local retinoid signals to the placode and forebrain. Together, these results suggest that local retinoid signaling is essential for the normal development of the mammalian olfactory pathway.

Acyclic Monoterpenes↗
PubMed1997

Markedly improved survival in malignant sacro-coccygeal teratomas--16 years, experience.

AIM OF STUDY: To see the impact of cisplatin- and carboplatin-based protocols on survival in malignant sacrococcygeal teratomas (SCT). METHODS: Twenty infants and children with malignant SCT were treated at the Hospital for Sick Children, Great Ormond Street, London, over a 16-year period from 1979 to 1994. There were 5 males and 15 females, age ranged from 1 day to 3.5 years (mean 18 months). RESULTS: Twelve patients (60%) had distant metastasis: 9 lung metastasis, 2 liver involvement, 2 bony metastases, 1 cerebral metastasis and 1 bilateral inguinal lymph node deposits. From 1982 to 1986, patients received the BEP chemotherapy protocol which included cis-platinum, bleomycin and etoposide (VP 16). After 1986, cis-platinum was replaced with carboplatin in the new JEB protocol. Patient 1 did not receive any chemotherapy, Patients 2-4 received varying protocols (2 deaths), Patients 5-8 received the BEP regime (1 death) and Patients 9-20 received JEB (1 death). The first three deaths were due to uncontrolled local disease and/or metastasis, while the latter death was due to bleomycin toxicity. Overall, 9 of 12 (75%) patients with distant metastasis survived as opposed to 7 of 8 (88%) patients with localised disease. Of the 12 patients who received the JEB protocol, 11 (92%) survived, including 7 patients with metastatic disease and 2 with local recurrence. Seven patients (35%) had relapse while on treatment or follow-up, 4 of these are disease-free with further therapy. In 6 of these children, serum AFP rose before there was clinical or radiological evidence of relapse. In 2 other patients, further chemotherapy was recommenced solely on the basis of rising serum AFP, these patients did not subsequently develop overt metastasis. CONCLUSIONS: We conclude that the treatment of choice for malignant SCT is the JEB regime, to be given for 4 courses or to be continued for 2 courses beyond documented Complete Response (CR). Excision of the primary tumour and coccyx should be done in all cases even if a CR has been documented. Metastases not responding to chemotherapy would need appropriate surgery, radiotherapy is hardly ever needed. An overall cure rate exceeding 90% can be expected.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Neonatal thymic haemorrhage.

Thymic haemorrhage in a neonate is an exceedingly rare condition. A case is presented of a neonate presenting at birth with cyanosis, respiratory distress and an anterior mediastinal mass. The radiological findings are demonstrated. After surgical excision and histopathological examination the lesion was found to be spontaneous haemorrhage into normal thymic tissue. Spontaneous thymic haemorrhage should be considered in any neonate developing acute respiratory distress with widening of the mediastinum and pleural effusion on chest radiography. Ultrasound may be used to support the diagnosis.

Acute Disease↗
PubMed1996

Associated urologic anomalies in low imperforate anus are capable of causing significant morbidity: a 15-year experience.

OBJECTIVES: To determine the incidence and morbidity caused by urologic anomalies in patients with low imperforate anus. METHODS: The case records and imaging studies of 95 patients who underwent surgery for low imperforate anus over a 15-year period were retrospectively reviewed. Follow-up ranged from 2 to 18 years (mean 5.4). RESULTS: Genitourinary abnormalities were seen in 29 patients (31%), whereas 10 (11%) had lumbosacral abnormalities. A micturating cystourethrogram was performed in 48 patients, 18 of whom were shown to have vesicoureteric reflux and 2 of whom required surgical correction. Three additional patients required bilateral ureteric reimplantation: 2 had megaureters whereas 1 had bilateral ectopic ureters. Four patients had evidence of chronic renal failure; these included 1 patient with reflux nephropathy, 2 with bilateral dysplastic kidneys, and 1 with neurogenic bladder. The patient with reflux nephropathy underwent renal transplantation at the age of 18 years. Two patients had proximal hypospadias and 4 had undescended testes. A neurogenic bladder was documented in 5 children, 4 of whom had lumbosacral abnormalities. One of these had a spinal lipoma and required excision of the lipoma and untethering of the spinal cord. CONCLUSIONS: We conclude that 30% of patients with low imperforate anus would have associated urologic anomalies, several of which are capable of causing significant morbidity. Thus, all patients with imperforate anus, whether high or low, need to be screened for associated urologic anomalies.

Abnormalities, Multiple↗
PubMed1996

Operative trauma to the genitourinary tract in the treatment of anorectal malformations: 15 years' experience.

OBJECTIVES: To determine the incidence of urologic trauma during surgical correction of anorectal malformations (ARM). METHODS: The records of 228 children with ARM were retrospectively reviewed. RESULTS: Operative trauma to the genitourinary tract was seen in 12 patients, all male. Of 133 patients with a high ARM, 92 underwent an abdominoperineal pull-through and 41 underwent a posterior sagittal anorectoplasty (PSARP); the incidence of urologic trauma was 12% and 0%, respectively. In the subgroup of male infants with a high ARM (99 patients), the incidence of genitourinary trauma was 11%; in those with a low anomaly, the incidence was 1 of 43 (2%). There were 3 urethral tears, 4 urethral strictures, 5 urethral diverticula, 2 vas deferens injuries, and 1 ureteric injury. Nine of the 12 patients do not have any long-term sequelae resulting from the injuries; however, 2 are now infertile and 1 has urinary incontinence. Four patients are additionally compromised because of an absent or nonfunctioning kidney on one side. CONCLUSIONS: In children with ARM, those undergoing a conventional pull-through repair are more likely to have a genitourinary injury than those undergoing the PSARP, and boys with high ARM are at greatest risk.

Anal Canal↗
PubMed1996

Management of the isolated congenital tracheo-oesophageal fistula.

Over a ten-year period sixteen infants with isolated congenital tracheo-oesophageal fistulas (TOF) were treated. All infants were symptomatic from birth although the diagnosis was only established in the neonatal period in eleven cases. Tube oesophagography was the diagnostic investigation of choice. Bronchoscopic cannulation of the fistula greatly assisted division, which was achieved through a cervical incision in all cases. There were two early recurrent fistulas both of which closed spontaneously. Persistent oesophageal symptoms were common. Seven of the patients (43%) experienced dysphagia, three of whom developed oesophageal strictures requiring repeated dilation.

Deglutition Disorders↗
PubMed1995

Management of alimentary tract duplication in children.

Duplication of the alimentary tract is rare but potentially dangerous. Five of 72 children with alimentary tract duplication treated between 1973 and 1992 died from postoperative complications; a further ten required more than one operation. Ileal duplications were the commonest, occurring in 16 patients (22 per cent). Thoracoabdominal duplications were the most complicated and responsible for much of the overall morbidity and mortality. Surgical complications were related to the size and location of the duplication, communication with the gastrointestinal tract or vertebral canal, presence of heterotopic gastric mucosa and involvement of mesenteric vessels. Complete excision of the duplication should be possible in most cases.

Adolescent↗
PubMed1995

Scattered radiation in a neonatal surgical unit.

We studied the doses of "scattered" received by neonates in a Neonatal Surgical Unit by placing thermoluminescent dosemeters in various positions expect the direct beam. Doses of "scattered" radiation received by neonates as a results of exposure of their neighbours to X-ray examinations were found to be negligible. Sick neonates need not be moved from their neighbours undergoing exposure to X-rays.

Humans↗
PubMed1994

Meconium ileus due to extensive intestinal aganglionosis.

Seven full-term infants with aganglionosis extending into the small bowel presented with clinical, radiological, and operative features of meconium ileus. Misdiagnosis resulted in inappropriate treatment. The correct diagnosis was eventually established by rectal suction biopsy, mostly after either recurrent intestinal obstruction or stomal dysfunction, and after cystic fibrosis had been excluded. For two patients, the results of rectal suction biopsies were initially misleading. Two infants died. Extensive intestinal aganglionosis should be considered a rare possibility in all infants with meconium ileus. In such cases, histological examination of the appendix may avoid this potential pitfall.

Biopsy, Needle↗
PubMed1994

Oesophageal atresia: at-risk groups for the 1990s.

The authors analyzed the outcome for 357 infants with oesophageal atresia and 15 with H-type tracheoesophageal fistula treated from 1980 through 1992. Survival according to Waterston risk categories was 99% for group A, 95% for group B, and 71% for group C. Presently, with optimal management, virtually all infants in groups A and B should survive. When examining the risk factors in the infants who died, two criteria were found to be important predictors of outcome: birth weight of less than 1,500 g and the presence of major congenital cardiac disease. A new classification for predicting outcome in oesophageal atresia is proposed: group I: birth weight > or = 1,500 g, without major cardiac disease, survival 97% (283 of 293); group II: birth weight < 1,500 g, or major cardiac disease, survival 59% (41 of 70); and group III: birth weight < 1,500 g, and major cardiac disease, survival 22% (2 of 9).

Abnormalities, Multiple↗
PubMed1993

Mediastinal teratomas: review of 15 pediatric cases.

One hundred fifty-three children with a teratoma presented to one hospital between 1970 and March 1992. The clinical and pathological features of 15 patients with mediastinal teratomas are reviewed; six were newborn and nine aged from infancy to 13 years. Thirteen patients including the six newborns presented with respiratory distress and all 15 patients had a mass on chest radiograph. A definite diagnosis of teratoma was not made preoperatively in any of these patients. At operation, a median sternotomy was used to approach seven anterior tumors and a lateral thoracotomy performed in the other eight patients. Histologically two were mature, 10 had immature elements, and three were malignant teratomas. The patients with malignant tumors were all over 12 years of age and died within 6 months of treatment. All six neonates had immature teratomas. Raised serum alpha-fetoprotein levels provided useful markers in two patients with recurrent tumors. Three conclusions can be drawn: (1) mediastinal teratomas are rare in children and frequently are not diagnosed before operation; (2) in newborns these tumors may be immature and present with respiratory distress; and (3) a median sternotomy gives excellent exposure for anterior mediastinal tumors.

Biomarkers, Tumor↗
PubMed1993

Recurrent necrotizing enterocolitis.

In the decade 1981 to 1991, 16 infants developed recurrent necrotizing enterocolitis (NEC). They comprised 12 (6%) of 196 neonates referred for further management of NEC and four others referred with major congenital anomalies. Their median gestational age was 32 weeks (range, 27 to 40), median birth weight was 1,260 g (range, 790 to 3,230), and the sex distribution was equal. Recurrent NEC occurred after a median interval of 37 days (range, 11 to 163) from the onset of the initial episode. All but one of the 16 infants were either premature (n = 10) or mature with major congenital anomalies (n = 5). Nine patients had previously undergone surgery for NEC. Medical treatment was successful in 11 patients with recurrent NEC. Two infants died, both of liver failure related to parenteral nutrition; one of whom had suffered four separate episodes of NEC and was found to have a superior mesenteric artery occlusion. There was no consistent association between recurrent NEC and the type or timing of enteral feeds or the anatomical site or method of management of the original attack. The mortality of 12.5% was similar to that for primary NEC.

Child↗
PubMed1993

Aortopexy for tracheomalacia in oesophageal anomalies.

Forty-eight patients with repaired congenital oesophageal anomaly underwent aortopexy for significant tracheomalacia between 1980 and 1990. Indications for aortopexy included recurrent apnoea/cyanosis in 31, near fatal episodes in 16, recurrent respiratory distress and infection in 20 and worsening stridor in 15. Gastro-oesophageal reflux was noted in 30 patients, recurrent fistula in 6 and oesophageal stricture in 14. Aortopexy cured near fatal episodes in all patients and resulted in improvement of airway obstruction in 95%. The procedure failed in 2 patients due to unrecognised bronchomalacia and phrenic nerve palsy respectively. Aortopexy is the primary procedure of choice for significant tracheomalacia when associated with near fatal episodes and significant airway obstruction.

Airway Obstruction↗
PubMed1993

Operation for gastro-oesophageal reflux associated with severe mental retardation.

One hundred and seventy six children with severe mental retardation underwent a fundoplication for considerable gastro-oesophageal reflux. There were six 'early' (3%) deaths and five 'late' deaths. Major complications developed in 17 (10%) children whereas 86 (49%) had 'minor' complications. A revision operation was required in 27 patients. Overall 142 (81%) children achieved a good result. In spite of the high complication rate and the need for a secondary operation in 15% of the patients, the quality of life for these children and their parents and carers is greatly improved by antireflux surgery.

Age Factors↗
PubMed1992

Childhood deaths from intussusception in England and Wales, 1984-9.

OBJECTIVE: To assess the incidence of potentially avoidable factors contributing to death of children with intussusception. DESIGN: Review of children who died with intussusception in England and Wales between 1984 and 1989 from data of the Office of Population Censuses and Surveys, case notes, coroners' records, and necropsy reports. MAIN OUTCOME MEASURES: Unambiguous objective criteria such as failure to diagnose intussusception within 24 hours of admission. RESULTS: 33 children died of acute intussusception in England and Wales between 1984 and 1989 compared with 67 in the previous six years. Their median age was 7 months (range 2 months to 12 years), and two thirds were boys. Half of the deaths occurred at home or soon after arrival at hospital but 15 patients had surgery. Potentially avoidable factors contributing to death were identified in 20 (61%) children, all but three of whom had ileocolic intussusception. These factors were excessive delay in diagnosis, inadequate intravenous fluid and antibiotic therapy, delay in recognising recurrent or residual intussusception after hydrostatic reduction, and surgical complications. Of the 13 patients in whom no avoidable factors were identified, there were nine of 11 children with isolated small bowel intussusception, who tended to have atypical presentations. CONCLUSION: Although the mortality from intussusception has declined, there remains ample opportunity for improved management.

Child↗