Search for mutations in the genes for coagulation factors V and VIII with a possible predisposition to activated protein C resistance

A total of 74 non-pregnant women with a previous episode of thrombosis were investigated for activated protein C (APC) resistance in the aPTT-based and factor IXa-X-based assays and for the presence of mutations in all APC-cleavage sites in the heavy chains of factor V and factor VIII. DNA fragments were amplified with the polymerase chain reaction (PCR) and those encoding for the Arg-306 and Arg-506 (factor V) and for Arg-740 (factor VIII) cleavage sites were subjected to restriction enzyme analysis. DNA fragments of 29 selected patients corresponding to the Arg-306 and Arg-679 cleavage sites in factor V, and to the Arg-336 and Arg-562 cleavage sites in factor VIII were sequenced. APC resistance was found in 40 cases, using the aPTT-based assay and in 35, using the factor IXa-X-based assay (23 patients were APC resistant in both assays), whereas 22 individuals had a normal response to APC. Forty-three patients carried Arg-506 to Gln mutation in factor V. No other polymorphism or mutation was found in the genes for factors V or VIII in the vicinity of the APC cleavage sites. It was concluded that the difference in response to APC in the two assays may not be explained by the presence of mutations in the APC cleavage sites of factor V and factor VIII in this group of patients. The data do not exclude the presence of mutations elsewhere in the factor V or factor VIII genes.     

Community acquired fulminant Pseudomonas infection of the gastrointestinal tract in previously healthy infants

Three previously healthy infants presented with diarrhoea and pyrexia and deteriorated rapidly. Two patients had necrotizing bowel disease requiring aggressive surgical intervention. All survived. P. aeruginosa gastrointestinal infection in previously healthy children is an extremely rare condition with a high mortality. Ecthyma gangrenosum was present in over 60% of reported cases although often not recognized initially. A high index of clinical suspicion, including prompt recognition of ecthyma gangrenosum, is mandatory for an early diagnosis of P. aeruginosa gastrointestinal infection. Early diagnosis and treatment may improve the prognosis.     

Chest radiography: a survey of techniques and exposure levels currently used

In diagnostic radiology, the routine measurement of exposure levels for a reference patient is an important part of an effective quality assurance program. In the United States, chest radiography is the most frequent examination and has the lowest exposure level of all radiologic examinations. We estimated the amount of exposure an average patient received from both manual and automatic exposure-controlled radiographic techniques by using a "patient-equivalent" chest phantom during measurements. A densitometric procedure was used to assess processor performance. The mean exposure from 194 chest systems was 20 mR (5.16 X 10(-5) C/kg); the mean film density, 1.38; and the mean processing speed, 108. It is interesting to note that a wide range of radiographic techniques, processing conditions, and screen-film speeds are currently being used. With the information given in our study, investigators can begin to identify the problems that lead to unusual exposure levels and, perhaps, poor image quality.     

SENSORINEURAL HEARING LOSS IN LINEAR IgA DISEASE

A 23-year-old female with progressive sensorineural hearing loss developed widespread blistering eruptions while under evaluation for the hearing loss. The lesions showed findings characteristic of linear IgA disease (LAD) on histochemical studies. Linear IgA disease is a dapsone responsive autoimmune subepidermal blistering disease characterised by linear IgA deposits in the basement membrane zone. The complete spectrum of this systemic disease is still not clear and this is the first report of association between LAD and sensorineural deafness.     

Coping flexibility in college students with depressive symptoms

Background  

The current study explored the prevalence of depressed mood among Chinese undergraduate students and examined the coping patterns and degree of flexibility of flexibility of such patterns associated with such mood.     

Ectopic pregnancy with postcoital contraception – a case report

The incidence of ectopic pregnancies is increasing. Common risk factors are tubal pathology, previous tubal surgery, previous ectopic pregnancy, intrauterine device use and embryo transfer. Levonelle-2^®, a progesterone-only postcoital contraceptive works by a combination of mechanisms including ovulation inhibition, prevention of fertilization, and inhibition of implantation. It is 85% effective and there have been 12 reported cases of ectopic pregnancy in the UK with its use. It is believed that progesterone slows the intratubal migration of the fertilized ovum. In the case reported here, a woman presented with an ectopic pregnancy after use of Levonelle-2 as postcoital contraception; there were no clinical predisposing risk factors. In the absence of any histological evidence of tubal damage, we suspect that the levonorgestrel from Levonelle-2 could have been responsible for delayed embryo transfer which resulted in the ectopic pregnancy.     

Essential role for Smad3 in angiotensin II‐induced tubular epithelial–mesenchymal transition

Angiotensin II (Ang II) is a key mediator of chronic kidney disease, in which epithelial–mesenchymal transition (EMT) is a critical process mediated by the TGFβ/Smad signalling pathway. The present study examined the specific role of Smads in Ang II‐induced EMT in vitro and in vivo. We found that Ang II signalled through the receptor of AT1, not AT2, to activate Smad2/3 and induce EMT in a normal rat tubular epithelial cell line (NRK52E). Activation of Smads by Ang II was attributed to degradation of an inhibitory Smad7, which was mediated by the AT1‐Smurf2‐dependent ubiquitin degradation mechanism because blockade of AT1 receptor or knockdown of Smurf2 inhibited Smad7 loss, thereby reducing Smad2/3 activation and EMT in response to Ang II. In contrast, over‐expression of Smad7 inhibited Ang II‐induced Smad2/3 activation and EMT in NRK52E cells and in a rat model of remnant kidney disease. Moreover, knockdown of Smad3, not Smad2, attenuated Ang II‐induced EMT. In conclusion, Ang II activates Smad signalling to induce EMT, which is mediated by a loss of Smad7 through the AT1‐Smurf2‐dependent ubiquitin degradation pathway. Smad3, but not Smad2, may be a mediator of EMT, while Smad7 may play a protective role in EMT in response to Ang II. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Functional consequences of an arginine180 to glutamine mutation in factor IX Hilo

Factor IX Hilo is a variant factor IX molecule that has no detectable coagulant activity. The defect in factor IX Hilo arises from a point mutation in the gene such that in the protein Arg180 is converted to a Gln. Activation of factor IX Hilo by factor Xla was monitored using the fluorescent active site probe p-aminobenzamidine. Normal factor IX showed complete activation in one hour as determined by measuring the increase in fluorescence when p-aminobenzamidine bound to activated factor IX. Factor IX Hilo showed no increase in fluorescence even after 24 hours, indicating that the active site was not exposed. Polyacrylamide gel electrophoresis showed that factor IX Hilo was cleaved to a light chain plus a larger peptide with a molecular weight equivalent to a heavy chain covalently linked to an activation peptide. Amino terminal amino acid sequencing of factor IX Hilo cleaved by factor Xla showed cleavage only at Arg145-Ala146, indicating that the Gln180-Val181 bond was not cleaved and that the active site was thus not exposed. The presence of factor IX Hilo in patient plasma was responsible for the patient having a very long ox brain prothrombin time characteristic of severe hemophilia Bm. Patient plasma had an ox brain prothrombin time of 100 seconds using a Thrombotest kit, significantly prolonged over the normal control value of 45 seconds. When factor IX Hilo was depleted from patient plasma using an immunoaffinity column, the ox brain prothrombin time decreased to 41 seconds. When factor IX Hilo was added back to depleted patient plasma, to normal plasma depleted of factor IX by the same affinity column, or to plasma from a CRM- hemophilia B patient, the ox brain prothrombin time was significantly prolonged. We conclude that the Arg180 to Gln mutation in factor IX Hilo results in a molecule that cannot be activated by factor Xla. Further, our data suggest that the mutation results in a molecule that interacts with components of the extrinsic pathway to give a prolonged ox brain prothrombin time.