Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11

In a large collaborative screening project, 370 men with idiopathic azoospermia or severe oligozoospermia were analysed for deletions of 76 DNA loci in Yq11. In 12 individuals, we observed de novo microdeletions involving several DNA loci, while an additional patient had an inherited deletion. They were mapped to three different subregions in Yq11. One subregion coincides to the AZF region defined recently in distal Yq11. The second and third subregion were mapped proximal to it, in proximal and middle Yq11, respectively. The different deletions observed were not overlapping but the extension of the deleted Y DNA in each subregion was similar in each patient analysed. In testis tissue sections, disruption of spermatogenesis was shown to be at the same phase when the microdeletion occurred in the same Yq11 subregion but at a different phase when the microdeletion occurred in a different Yq11 subregion. Therefore, we propose the presence of not one but three spermatogenesis loci in Yq11 and that each locus is active during a different phase of male germ cell development. As the most severe phenotype after deletion of each locus is azoospermia, we designated them as: AZFa, AZFb and AZFc. Their probable phase of function in human spermatogenesis and candidate genes involved will be discussed.      

Prolonged intravenous remifentanil infusion for labor analgesia

IMPLICATIONS: A 34-h remifentanil infusion was administered for labor analgesia in a patient with thrombocytopenia and renal insufficiency. Compared with other opioids, remifentanil may produce fewer cumulative effects during prolonged infusion because of its unique metabolism.     

Pediatric emergency preparedness in the office

Pediatric office emergencies occur more commonly than is usually perceived by family physicians, and most offices are not optimally prepared to deal with these situations. Obtaining specific training in pediatric emergencies and performing mock "codes" to check office readiness can improve the proper handling of pediatric emergencies. Common airway emergencies include foreign-body aspiration and croup. Cool mist, racemic epinephrine nebulization and dexamethasone are typical treatment measures for croup. Asthma and bronchiolitis are common causes of respiratory distress. Hypovolemic shock is the most common cause of circulatory failure in children. Intraosseous access is a simple and underutilized route for vascular access in a critically ill child. Status epilepticus is the most common neurologic emergency. Avoidance of iatrogenic respiratory depression and hypotension can be optimized by taking an algorithmic approach to the use of anticonvulsant medications. Transport of patients after initial stabilization of an emergency should always be done in a manner that provides adequate safety and monitoring.     

The international collaborative study of maternal phenylketonuria: status report 1994

Neonatal screening for phenylketonuria (PKU) has created a problem as females with PKU are reaching child-bearing age. Surveys have revealed that maternal phenylalanine blood concentrations greater than 1200 μmol/l are associated with fetal microcephaly, congenital heart defects and intrauterine growth retardation. It is estimated that as many as 3000 hyperphenylalaninemic females may be at risk of producing these fetal abnormalities. To examine this problem, the international maternal PKU collaborative study was developed to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity. Preliminary findings have indicated that phenylalanine restriction should begin before conception for females with PKU planning a pregnancy. Dietary control should maintain maternal blood phenylalanine levels between 120 and 360 μmol/l and should provide adequate energy, protein, vitamin and mineral intake. Pregnant hyperphenylalaninemic females who achieved metabolic control after conception or by the 10th week of pregnancy had a better offspring outcome than anticipated. The results of 402 pregnancies are reviewed.     

The Abortion and Sterilization Act in 1975--experience of the Johannesburg Hospital Pregnancy Advisory Clinic

The experience of a Pregnancy Advisory Service operating in terms of the Abortion and Sterilization Act of 1975 is reviewed. A total of 454 applications for abortion were considered, of which 198 (44%) were accepted and the abortions performed. The urgent need for sex education at schools, colleges and universities is stressed, in view of the large number of scholars and students under the age of 17 who seek an abortion. There are also patients who discontinue contraception for a variety of reasons, on medical advice or otherwise, without an alternative being suggested or sought. Motivation of patient, nurse and doctor needs urgent improvement.