Predictors of mortality and nephrectomy in emphysematous pyelonephritis: a tertiary care centre study

INTRODUCTION

Emphysematous pyelonephritis (EPN) is a deadly disease due to its associated morbidity and mortality. Attempts have been made to identify predictors of severity, mortality and need for nephrectomy in EPN with little success.

METHODS

We conducted an ambispective study of EPN patients between March 2014 and September 2019. Retrospective data were collected which included age, sex, comorbidities, symptoms, signs, laboratory investigations including imaging, need for dialysis, management and any complications. All patients were then followed prospectively for renal dynamic scan, stone surgery or nephrectomy. Univariate analysis was performed to identify factors affecting mortality and need for elective nephrectomy.

RESULTS

In total, 112 patients were included. Mean patient age was 50.01 years, 55% were female and 5% had bilateral involvement. Fever and flank pain were the most common symptoms. Diabetes was seen in 75% of cases and 30% of cases required haemodialysis at initial presentation. About 60% of patients improved with pigtail drainage. Need for nephrectomy was greater in Huang-Tseng stage 3a (14.8%). Huang-Tseng stages 3b and 4 had higher mortality rates (25%) than the other stages (2.2%). Twelve of 99 patients had non functional kidney on follow-up and underwent elective nephrectomy. Low platelet counts, high body mass index, septic shock, dialysis and higher Huang-Tseng stage were found to be predictive of mortality and renal parenchymal thickness on computed tomography scan was predictive of follow-up nephrectomy.

CONCLUSIONS

Thrombocytopaenia, high body mass index, septic shock, haemodialysis and higher Huang-Tseng stage are predictors of mortality and renal parenchymal thickness <5mm is a predictor of poor salvage of affected kidney on follow-up.

Fully Automatic Method for Reliable Spinal Cord Compartment Segmentation in Multiple Sclerosis

BACKGROUND AND PURPOSE

Fully automatic quantification methods of spinal cord compartments are needed to study pathologic changes of the spinal cord GM and WM in MS in vivo. We propose a novel method for automatic spinal cord compartment segmentation (SCORE) in patients with MS.

MATERIALS AND METHODS

The cervical spinal cords of 24 patients with MS and 24 sex- and age-matched healthy controls were scanned on a 3T MR imaging system, including an averaged magnetization inversion recovery acquisition sequence. Three experienced raters manually segmented the spinal cord GM and WM, anterior and posterior horns, gray commissure, and MS lesions. Subsequently, manual segmentations were used to train neural segmentation networks of spinal cord compartments with multidimensional gated recurrent units in a 3-fold cross-validation fashion. Total intracranial volumes were quantified using FreeSurfer.

RESULTS

The intra- and intersession reproducibility of SCORE was high in all spinal cord compartments (eg, mean relative SD of GM and WM: ≤ 3.50% and ≤1.47%, respectively) and was better than manual segmentations (all P < .001). The accuracy of SCORE compared with manual segmentations was excellent, both in healthy controls and in patients with MS (Dice similarity coefficients of GM and WM: ≥ 0.84 and ≥0.92, respectively). Patients with MS had lower total WM areas (P < .05), and total anterior horn areas (P < .01 respectively), as measured with SCORE.

CONCLUSIONS

We demonstrate a novel, reliable quantification method for spinal cord tissue segmentation in healthy controls and patients with MS and other neurologic disorders affecting the spinal cord. Patients with MS have reduced areas in specific spinal cord tissue compartments, which may be used as MS biomarkers.

Emphysematous cystitis: an incidental finding with varying outcomes

Emphysematous cystitis (EC) is a rare severe urinary tract infection characterised by pockets of air in and around the urinary bladder wall caused by gas-forming organisms. Common predisposing factors are chronic infection, immunosuppression, diabetes and neurogenic bladder. The presentation may vary from mild illness to severe life-threatening cystitis. We report two cases of incidental detection of EC diagnosed on imaging for the evaluation of unrelated symptoms. Although asymptomatic, this lethal disease still warrants prompt recognition and treatment with broad-spectrum antibiotics and urinary bladder drainage to prevent severe morbidity and mortality.

Lysinibacillus macroides-mediated control of cellulose-producing morphotype of Salmonella

BACKGROUND

Soil-dwelling human pathogens like Salmonella are transmitted by fresh produce such as tomato, spinach, onion and cabbage. With >2600 serovars, it is difficult to classify the good plant colonizers from the non-colonizers. Generally, soil microbiota are classified as autochthonous or zymogenous organisms, based on their ability to survive in soil. However, such information for soil-dwelling human pathogens is not available Thus there is a need to classify these organisms for designing a strategy to prevent their outbreak. Moreover, soil harbours a plethora of microbes, which can be screened for competitive organisms to control such human pathogens.

RESULTS

In this study, we examined whether the morphotype based on the attachment factors (e.g., cellulose and curli fimbri) of Salmonella was important for its colonization of roots. Secondly, we tracked the location of the bacteria in the plant cell. Interestingly, most of the epidermal cells occupied by Salmonella showed propidium iodide-positive nuclei. As an extension of the study, a screening of competitive rhizospheric bacteria was performed. One isolate, identified as Lysinibacillus macroides, was able to inhibit the biofilm of Salmonella and subsequently reduced its colonization on roots.

CONCLUSION

Based on this study, we classified the Rdar (red, dry and rough) morphotypes as good plant colonists. The ability to colonize and subsequent kill the live plant cell throws light on the zymogenous life cycle of soil-dwelling Salmonella. Additionally, Lysinibacillus macroides served as a biocontrol agent by reducing the burden of Salmonella in various vegetables. Such organisms can further be explored to prevent contamination of the food chain. © 2022 Society of Chemical Industry.

Immunotherapy in head and neck squamous cell carcinoma: An updated review

Squamous cell cancer of the head and neck (HNSCC) is the sixth most common cancer and is associated with significant morbidity and mortality. The tumor microenvironment for HNSCC is a complex interplay of immune cells, stromal cells, and cytokines amongst others. Immunotherapy acts as an effective antineoplastic agent by influencing this complex environment and includes immune checkpoint inhibitors (ICI). ICI have been approved in the frontline setting for recurrent and metastatic (R/M) HNSCC as well as platinum-refractory (second line) R/M HNSCC. However, recent clinical studies highlight that the response to immunotherapy varies, and different ICI, as well as different combination strategies play a crucial role in augmenting the efficacy of immunotherapy. An in-depth analysis and focused study of the immune contexture in patients with HNSCC receiving ICI remains critical. Many novel immunotherapies including CAR-T cell therapy, oncolytic virus therapy, and vaccines are underway. Ongoing trials are testing ICI in the neoadjuvant and adjuvant settings. Furthermore, identifying better biomarkers to target population that benefits from immunotherapy is of paramount importance. Pioneering the optimal combination regimen utilizing new novel immunotherapy has recently become a paradigm shift in the HNSCC treatment landscape. Herein, we summarize the clinical development with all ongoing clinical trials of immunotherapy in HNSCC.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Small renal mass with large lymph nodal metastasis and inferior vena cava thrombus: an exceptional amalgamation

A small renal mass is defined as a tumour <4cm. The standard treatment of choice for small renal masses is partial or radical nephrectomy, depending on the tumour anatomy, and has good overall and cancer-specific survival. Its association with lymph node metastasis and inferior vena cava (IVC) thrombus is very uncommon. We describe a case of a right small renal mass with a large metastatic paracaval lymph node with IVC level I thrombus who was treated with right radical nephrectomy with thrombus removal and lymph node excision.

Massive intratumoral bleed in renal cell cancer: an unusual life-threatening event

Renal cell cancer (RCC) commonly presents as an asymptomatic incidental mass on imaging for other abdominal pathologies. Because of its hypervascular nature, spontaneous haemorrhage, although very rare, can be seen with RCC. Spontaneous haemorrhage may present with flank pain, fever and sudden abdominal distension with or without haemorrhagic shock. Although unusual, spontaneous haemorrhage is potentially serious, and therefore clinicians should be aware of such events. Imaging may be difficult to interpret in view of intratumoral and perinephric haemorrhage. Prompt diagnosis and treatment is essential for a successful outcome. We report a case of massive intratumoral bleed in RCC in a young male and its management by renal artery angioembolisation followed by radical nephrectomy.

Bilateral obstructive megaureter with right lower ureteric urothelial carcinoma: a very rare coalition

Upper tract urothelial cancers account for 5% of all urothelial cancers. Among these, more than 90% of tumours are located in the renal pelvis, while ureteric tumours are extremely rare. The distal ureter is the most common location, although multifocal implants may also occur. Megaureter is a common cause of obstructive uropathy in neonates and children. Nevertheless, it may be unnoticed, if asymptomatic. Megaureter may be obstructing or refluxing. Long-standing urinary stasis and recurrent urinary tract infection in megaureter may cause chronic irritation of the ureteric mucosa leading to dysplasia and malignancy. We report a 55-year-old man diagnosed with bilateral obstructive megaureter with right lower ureteric urothelial cancer and review the current literature.

Metachronous isolated inferior vena cava tumour thrombus in renal cell cancer: a rare aftermath

Renal cell cancer (RCC) accounts for 3% of all solid malignancies. Synchronous tumour thrombus in the renal vein or inferior vena cava is reported in 4-10% cases and is a surgical challenge. Contemporary imaging modalities that are used to define the presence and extent of venous thrombus include colour Doppler, contrast-enhanced computed tomography and magnetic resonance venography. Surgical management depends upon the degree of tumour thrombus. We report isolated recurrence of RCC in the inferior vena cava 2 years after radical nephrectomy, and discuss its pathophysiology and management.

IgG4-related retroperitoneal fibrosis: a rare cause of obstructive uropathy

Immunoglobulin G4 (IgG4)-related disease was described in 2003 and is known to affect almost all organ systems. Rarely, this disease can manifest in the retroperitoneum, which can lead to sequalae such as obstructive uropathy. Here we describe a case of IgG4-related retroperitoneal fibrosis leading to obstructive uropathy. The patient was managed with bilateral Double J (DJ) stenting and oral steroids. Following remission of the disease, the DJ stents were removed and the patient remained asymptomatic over the follow-up period. A high index of suspicion is required for diagnosis of this rare disease and timely management can lead to a positive outcome.

Multidisciplinary management of a complex case of renal cell carcinoma arising in a pelvic kidney

The incidence of ectopic kidney is 1 in 2100-3000 autopsies. Renal cell cancer (RCC) in pelvic kidney is a rare entity with limited case reports available in the literature. Symptoms can vary from abdominal pain to haematuria, or RCC can be detected incidentally. Contrast imaging with computed tomography (CT) angiography is recommended to determine the location of the renal mass and the anatomy of surrounding organs and major vessels feeding it. Treatment of choice is radical nephrectomy. We report a case of RCC in ectopic pelvic kidney managed with radical nephrectomy that was deemed unresectable on CT imaging.

Impact of opioid maintenance treatment during pregnancy on neonatal birth weight and head circumference

BACKGROUND

Pregnant mothers with opioid dependency commonly receive maintenance treatment of opioid (OMT), either as buprenorphine (BMT) or methadone maintenance treatment (MMT). We investigated, whether OMT adversely affects standardized neonatal anthropometric outcomes and whether BMT is potentially safer than MMT in this regard.

METHODS

Retrospective chart review of mother infant dyad, with and without OMT. Infant's absolute and standardized (z-score) anthropometric outcomes at birth were first compared, between OMT and control group (negative meconium drug screen), and then between BMT and MMT group. These outcomes were also compared between infants who did or did not require treatment after birth for neonatal abstinence syndrome (NAS).

RESULT

A total of 1479 participants with MDS were included [Control = 1251; OMT = 228 (MMT = 181; BMT = 47)]. Both the z-scores of birth weight (BW) and head circumference (HC) was lower in OMT group (p <  0.001). Among the OMT group, GA at delivery was slightly higher in the BMT group (p = 0.05). There was an inverse correlation between maternal dose at the time of delivery and anthropometric z-scores in the BMT group, mainly in female infants (BW: p = 0.006; HC: p = 0.003). Furthermore, In BMT group, infants with lower HC were more likely to require treatment for NAS (p = 0.01).

CONCLUSION

HC and BW when comparing Z-scores were not different between MMT and BMT. High maternal dosing of buprenorphine is associated with lower BW and HC Z-scores but dose effect is not seen with methadone. In addition, there seems to be an association between NAS severity and HC, especially in the BMT group.

Penile fracture associated with complete urethra and bilateral corpora cavernosa transection

Penile fracture is a rare urological emergency caused by blunt trauma to the erect penis. It occurs due to the forcible bending of the turgid erect penis against resistance leading to tunica albuginea tear. The rupture of tunica albuginea surrounding the corpora cavernosa leads to hematoma formation and classical 'aubergine' deformity. Timely intervention is essential to improve sexual function. Urethral injury may occur concomitantly in case of severe trauma. Blood at the meatus, inability to void and haematuria are distinctive features. We describe a case of 36-year-old man who presented to the emergency department with penile fracture during sexual intercourse associated with blood at the meatus and voiding difficulty. On surgical exploration, complete bilateral corpora cavernosa tear and penile urethral transection was noted. The patient was successfully managed with timely repair. This case highlights the need for suspicion of an associated urethral injury in patients of penile fracture with blood at the meatus.

Large distal ureteric stone with high burden urothelial cancer of the entire ureter and renal pelvis: a dual pathology

Upper-tract urothelial cancer comprises only 3% of all urothelial cancers. Risk factors include tobacco smoking, recurrent urinary infection, urolithiasis and analgesic abuse. Urolithiasis-induced chronic inflammation leads to urothelial proliferation and eventual malignant transformation. The most common association is reported with squamous cell cancer. A 54-year man under evaluation for right flank pain was diagnosed with a large distal ureteric stone and urothelial cancer of the entire right ureter and renal pelvis. The patient underwent right nephroureterectomy and stone retrieval, with urinary bladder cuff excision and pelvic lymph node dissection. On follow-up, the patient succumbed to disease recurrence with widespread metastasis. Urothelial cancer associated with stone disease is atypical. Long-standing inflammation causing metaplastic and dysplastic changes is a possible hypothesis. Careful assessment of the malignancy should be looked for in patients with long-standing obstruction due to stone disease.

Cutaneous Adverse Drug Reactions to Targeted Chemotherapeutic Drugs: A Clinico-Epidemiological Study

Background:

Targeted chemotherapeutic drugs have led to a remarkable improvement in the survival of cancer patients but also have resulted in the increased incidence of uncommon but specific muco-cutaneous adverse effects.

Aims:

This study aimed to highlight the spectrum of such cutaneous adverse drug reactions and to derive a causal association.

Materials and Methods:

A hospital-based, descriptive study was carried out in the dermatology outpatient department between August 2016 and July 2018, on patients referred from the state cancer institute, who developed muco-cutaneous lesions after the initiation of targeted chemotherapeutic drugs.

Results:

A total of 80 patients, 59 (74%) males and 21 (26%) females of mean age 45.83 ± 16.37 years (range 4–70 years) developed one or more uncommon albeit specific muco-cutaneous adverse effects. Among them, papulopustular and acneiform eruptions were found in 21 patients (26.25%), and PRIDE complex was seen in 3 patients. Sixteen patients (20.00%) developed palmar-plantar erythrodysesthesia, 8 patients (10%) developed lichenoid drug eruption, and 5 patients (6.25%) developed flagellate dermatitis. Twenty-two (27.5%) patients showed nail changes, the most common, being melanonychia.

Conclusion:

There has been a paradigm shift in the management of both hematopoietic and solid cancers with the advent of targeted chemotherapeutic drugs leading to an increase in uncommon and specific drug reactions. Early recognition of these decreases morbidity, improves quality of life, and allows continuation of the life saving chemotherapy.

Automatic Spinal Cord Gray Matter Quantification: A Novel Approach

BACKGROUND AND PURPOSE

Currently, accurate and reproducible spinal cord GM segmentation remains challenging and a noninvasive broadly accepted reference standard for spinal cord GM measurements is still a matter of ongoing discussion. Our aim was to assess the reproducibility and accuracy of cervical spinal cord GM and WM cross-sectional area measurements using averaged magnetization inversion recovery acquisitions images and a fully-automatic postprocessing segmentation algorithm.

MATERIALS AND METHODS

The cervical spinal cord of 24 healthy subjects (14 women; mean age, 40 ± 11 years) was scanned in a test-retest fashion on a 3T MR imaging system. Twelve axial averaged magnetization inversion recovery acquisitions slices were acquired over a 48-mm cord segment. GM and WM were both manually segmented by 2 experienced readers and compared with an automatic variational segmentation algorithm with a shape prior modified for 3D data with a slice similarity prior. Precision and accuracy of the automatic method were evaluated using coefficients of variation and Dice similarity coefficients.

RESULTS

The mean GM area was 17.20 ± 2.28 mm² and the mean WM area was 72.71 ± 7.55 mm² using the automatic method. Reproducibility was high for both methods, while being better for the automatic approach (all mean automatic coefficients of variation, ≤4.77%; all differences, P < .001). The accuracy of the automatic method compared with the manual reference standard was excellent (mean Dice similarity coefficients: 0.86 ± 0.04 for GM and 0.90 ± 0.03 for WM). The automatic approach demonstrated similar coefficients of variation between intra- and intersession reproducibility as well as among all acquired spinal cord slices.

CONCLUSIONS

Our novel approach including the averaged magnetization inversion recovery acquisitions sequence and a fully-automated postprocessing segmentation algorithm demonstrated an accurate and reproducible spinal cord GM and WM segmentation. This pipeline is promising for both the exploration of longitudinal structural GM changes and application in clinical settings in disorders affecting the spinal cord.

Retroperitoneal paraganglioma: a chameleon masquerading as an adrenal pheochromocytoma

Retroperitoneal paragangliomas are rare tumours arising from neural crest cells located near or in the autonomic nervous system; right from the skull bass to the pelvic floor. Often called the great masqueraders, their diagnosis and treatment is often difficult and fraught with danger, considering the close proximity of these tumours to important retroperitoneal organs. A 29-year-old woman presented to the outpatient department with complaints of paroxysms of headache, sweating and palpitations for one year. She was found to have elevated urinary metadrenalines (metanephrines) and a suprarenal mass on contrast-enhanced computed tomography of the abdomen, which demonstrated increased tracer activity on I-131 iodine-123 meta-iodobenzylguanidine scintigraphy. Adrenal pheochromocytoma was diagnosed and she underwent laparoscopic adrenalectomy after stabilisation of her blood pressure. Laparoscopy revealed a large suprarenal mass with dense adhesions to the inferior vena cava that was carefully separated from the vein and surrounding structures. The cut section revealed a heterogeneous mass encasing a normal adrenal gland and histopathology confirmed the same, confirming the final diagnosis of retroperitoneal paraganglioma.

Endothelial and platelet microparticles in patients with antiphospholipid antibodies

BACKGROUND

The antiphospholipid syndrome (APS) is the association of thrombosis and recurrent pregnancy loss and/or pregnancy morbidity with persistent antiphospholipid antibodies (aPL). Previous studies of microparticles in patients with APS/aPL have mainly been small and findings, contradictory.

OBJECTIVES

To quantify endothelial and platelet microparticle levels in patients with isolated antiphospholipid antibodies or primary antiphospholipid syndrome (PAPS).

PATIENTS/METHODS

We measured endothelial and platelet microparticle levels by flow cytometry in 66 aPL/PAPS patients and 18 healthy controls.

RESULTS

Levels of circulating platelet (CD41 and CD61) and endothelial microparticles (CD51 and CD105) were significantly increased in patients with PAPS and aPL compared to healthy controls. There were correlations between platelet and endothelial microparticles levels in all patients with aPL.

CONCLUSIONS

Platelet and endothelial microparticles are increased in all patient groups within this cohort of patients aPL. Whether they may have a role in the pathogenesis of APS merits further study.

Investigation on Cu(II) adsorption on cobalt silicate precipitation tube (CSPT) in aqueous medium

Cu(II) adsorption on cobalt silicate precipitation tube (CSPT) in aqueous medium has been reported. These tubes are porous with negative surface sites having isoelectric point (IEP) at pH 4.4. Cu(II) adsorption data follow Langmuir isotherm. CSPT has high Cu(II) loading capacity, which is a function of both Cu(II) concentration and CSPT weight. Adsorption bond energy obtained from Langmuir isotherm suggests a physisorption process. The adsorption process is endothermic and spontaneous. Adsorption kinetics follows pseudo second order model with activation energy (15.4 kJ mol(-1)) typical for physisorption process.

Pregnancy outcome and fibrinolytic, endothelial and coagulation markers in women undergoing uterine artery Doppler screening at 23 weeks

BACKGROUND

Pre-eclampsia (PET) and/or fetal growth restriction (FGR) remain a major cause of maternal and fetal morbidity and mortality. In pregnancy, fibrinolysis is controlled by the maternal endothelium and placenta, both of which are central to the pathogenesis of PET/FGR. Clinically, uterine artery Doppler screening at 23 weeks is used to predict PET/FGR. An abnormal uterine artery Doppler finding is defined as early diastolic bilateral uterine artery notching (BN) in the waveform. However, about 50% of mothers with BN do not develop PET/FGR.

OBJECTIVES

We investigated fibrinolytic changes and uterine artery Doppler findings in the second trimester, and related them to pregnancy outcome; in particular assessing whether fibrinolytic markers could discriminate between normal and abnormal outcome in mothers with BN.

PATIENTS/METHODS

Plasma levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), plasminogen activator inhibitor-2 (PAI-2), plasmin-alpha(2) antiplasmin (PAP), D-dimers and markers of endothelial dysfunction were measured with Doppler ultrasound at 23 weeks.

RESULTS

Those with BN had decreased PAP and D-dimer levels, and raised PAI-1 and thrombomodulin levels. Mothers with BN and PET/FGR had significantly increased t-PA levels and reduced PAI-2 levels.

CONCLUSIONS

BN at 23 weeks of gestation is associated with increased PAI-1 levels. Within the BN group, mothers who developed PET/FGR had increased t-PA levels and decreased PAI-2 levels, although there was no net change in fibrinolysis as measured by D-dimer levels. No single fibrinolytic marker is helpful in determining pregnancy outcome in those with BN, but t-PA and PAI-2 are worthy of study in a multifactorial algorithm.

Screening for proximal deep vein thrombosis after acute ischemic stroke: a prospective study using clinical factors and plasma D-dimers

Deep vein thrombosis (DVT) remains common in patients with acute ischemic stroke (AIS) receiving aspirin and graded compression stockings (considered standard thromboprophylaxis in the UK), most events occurring in patients with Barthel indices (BI) of <9 ('severe stroke') around the time of admission. In the absence of data indicating improved clinical outcomes with use of low-dose anticoagulant thromboprophylaxis, we evaluated the hypothesis that plasma D-dimers (D-d) might be a valuable initial screening test for proximal DVT (PDVT), facilitating selective use of imaging. One hundred and two unselected AIS-patients receiving aspirin/graded compression stockings thromboprophylaxis were screened for DVT using magnetic resonance direct thrombus imaging, a highly accurate non-invasive technique which directly visualizes thrombus. D-d (VIDAS and IL test D-d assays) were measured on recruitment and at weekly intervals. Median D-d were significantly higher throughout the study in patients with severe stroke who developed PDVT vs. those with severe stroke not developing PDVT, differences being most marked around day 9. Depending on the discriminatory threshold used, a single D-d measurement at this time in patients with severe-AIS allowed identification of a subgroup with ~50% prevalence of PDVT. Sensitivity of these strategies for PDVT was 67-83%, at a cost of imaging 22-30% of the entire cohort of patients. A single measurement of BI around the time of admission and D-d level at day 9 in AIS-patients receiving aspirin/graded compression stockings thromboprophylaxis allows identification of a subgroup containing a substantial proportion of all PDVTs who could be selectively imaged.

Detection of human papillomavirus from liquid-based cytology specimens by in-house PCR: a pilot study

The Papanicolaou smear remains the most common method for the detection of precancerous changes in cervical cytology. However, the introduction of a liquid-based cytology (LBC) technique expands the possibility of cervical intraepithelial neoplasia (CIN) diagnosis, and permits detection of precancerous changes and human papillomavirus (HPV) simultaneously. In the pilot study reported here, using an in-house polymerase chain reaction (PCR) method, high-grade HPV was detected in 32% of a cohort of 38 patients. This conventional PCR method could be developed for use on a real-time PCR platform or in a microtitre-well format and subsequently automated.

Is mild normobaric hypoxia a risk factor for venous thromboembolism?

BACKGROUND

Modern air travel entails a cabin altitude between 1520 and 2440 m (5000-8000 ft) and thus exposure to mild hypoxia. There is debate as to whether hypoxia is causally related to venous thromboembolism (VTE) occurring during or after travel. One study suggested that a short period of hypobaric hypoxia causes activation of coagulation.

OBJECTIVES

To test the hypothesis that hypoxia alone (normobaric hypoxia) causes activation of coagulation, possibly through endothelial cell activation.

METHODS

Six healthy male volunteers were exposed for 3 h, while seated, on two separate occasions to (i) dry air (control) and (ii) hypoxic gas mixture (12.8% O2 in N2, equivalent to breathing air at 3660 m [12000 ft]).

RESULTS

There were no differences in hemostatic or endothelial markers between control and hypoxic groups, but platelet and leukocyte counts increased and were significantly higher in the hypoxic group. There were increases in fibrinogen and von Willebrand factor, as well as rheological changes, but these were not significantly different between control and hypoxic groups.

CONCLUSIONS

This small study does not support the previous suggestion that hypoxia causes activation of coagulation, and suggests that immobility-induced rheological changes may be more significant in the etiology of VTE occurring during or after travel.

Activated c-Met signals through PI3K with dramatic effects on cytoskeletal functions in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive illness with early metastases. There are several receptor tyrosine kinases (RTKs) overexpressed in SCLC, including c-Met. c-Met contains an external semaphorin-like domain, a cytoplasmic juxtamembrane domain, tyrosine kinase domain and multiple tyrosines that bind to adapter molecules. We have previously reported that c-Met is abundantly expressed in the NCI-H69 SCLC cell line and now have determined the downstream effects of stimulating c-Met via its ligand hepatocyte growth factor (HGF). Utilizing unique phospho-specific antibodies generated against various tyrosines of c-Met, we show that Y1003 (binding site for c-Cbl and a negative regulatory site), Y1313 (binding site for PI3K), Y1230/Y1234/Y1235 (autophosphorylation site), Y1349 (binding site for Grb2), Y1365 (important in cell morphogenesis) are phosphorylated in response to HGF (40 ng/ml, 7.5 min) in H69 cells. Since multiple biological and biochemical effects are transduced through the PI3K pathway, we determine the role of PI3K in the c-Met/HGF stimulation pathway. We initially determined that by inhibiting PI3K with LY294002 (50 microM over 72 hours), there was at least a 55% decrease in viability of H69 cells. Since H69 SCLC cells form clusters in cell culture, we determined the effects of HGF and LY294002 on cell motility of the clusters by time-lapse video microscopy. In response to HGF, SCLC moved much faster and formed more clusters, and this was inhibited by LY294002. Finally, we determined the downstream signal transduction of HGF stimulation of c-Met with and without inhibition of c-Met (with geldanamycin, an anisamycin antibiotic that inhibits c-Met in SCLC) or PI3K (with LY294002). We show that association of c-Met with PI3K and GAB2 is diminished by inhibiting c-Met. In summary, activation of the c-Met pathway targets the PI3K pathway in SCLC and this may be an important therapeutic target.

The effects of aprotinin on thromboelastography with three different activators

BACKGROUND

Thromboelastography is used for assessment of hemostasis. Adherence to thromboelastography-guided algorithms and aprotinin administration each decrease bleeding and blood product usage after cardiac surgery. Aprotinin, through inhibition of kallikrein, causes prolongation of the celite-activated clotting time and the activated partial thromboplastin ratio. The aim of this study was to assess the effects of aprotinin on the thromboelastography trace.

METHODS

Three activators were used in the thromboelastography: celite (which is widely established), kaolin, and tissue factor. Assessment was performed on blood from volunteers and from patients before and after cardiac surgery.

RESULTS

The tissue factor-activated thromboelastography trace was unaffected by the addition of aprotinin. When celite and kaolin were used as activators in the presence of aprotinin, the reaction time (time to clot formation) of the thromboelastography trace was prolonged (P < 0.0001) and the maximum amplitude (clot strength) was decreased (P < 0.05). With celite as an activator, the addition of aprotinin decreased (P < 0.05) the thromboelastography alpha angle (rate of clot extension). The reaction time of the celite-activated trace correlated with the activated partial thromboplastin ratio (P < 0.01). The reaction time of the tissue factor-activated trace correlated with the international normalized ratio (P < 0.01).

CONCLUSION

The thromboelastography trace is altered in the presence of aprotinin when celite and kaolin are used as activators but not when tissue factor is the activator.

Temperature-sensitive transformation by an Abelson virus mutant encoding an altered SH2 domain

Abelson murine leukemia virus (Ab-MLV) encodes the v-Abl protein tyrosine kinase and induces transformation of immortalized fibroblast lines and pre-B cells. Temperature-sensitive mutations affecting the kinase domain of the protein have demonstrated that the kinase activity is absolutely required for transformation. Despite this requirement, mutations affecting other regions of v-Abl modulate transformation activity. The SH2 domain and the highly conserved FLVRES motif within it form a phosphotyrosine-binding pocket that is required for interactions between the kinase and cellular substrates. To understand the impact of SH2 alterations on Ab-MLV-mediated transformation, we studied the Ab-MLV mutant P120/R273K. This mutant encodes a v-Abl protein in which the beta B5 arginine at the base of the phosphotyrosine-binding pocket has been replaced by a lysine. Unexpectedly, infection of NIH 3T3 or pre-B cells with P120/R273K revealed a temperature-dependent transformation phenotype. At 34 degrees C, P120/R273K transformed about 10-fold fewer cells than wild-type virus of equivalent titer; at 39.5 degrees C, 300-fold fewer NIH 3T3 cells were transformed and pre-B cells were refractory to transformation. Temperature-dependent transformation was accompanied by decreased phosphorylation of Shc, a protein that interacts with the v-Abl SH2 and links the protein to Ras, and decreased induction of c-Myc expression. These data suggest that alteration of the FLVRES pocket affects the ability of v-Abl to interact with at least some of its substrates in a temperature-dependent fashion and identify a novel type of temperature-sensitive Abelson virus.

Systemic endothelial cell markers in primary antiphospholipid syndrome

The pathogenic mechanism underlying the prothrombotic tendency of Hughes' or antiphospholipid syndrome (APS) has not been elucidated. Numerous procoagulant mechanisms have been tested including platelet activation, monocyte tissue factor (TF) expression and endothelial cell (EC) activation. There is some evidence for the latter from studies on cultured human umbilical vein endothelial cells (HUVEC). Incubation with antiphospholipid antibodies (aPL) induces EC activation in vitro. We investigated whether there was evidence of EC perturbation in vivo using enzyme-linked immunosorbant assays (ELISAs) for soluble markers of EC dysfunction. Serum and plasma were collected from controls and patients with primary APS and ELISAs performed to quantify soluble vascular cell adhesion molecule (sVCAM), soluble intercellular adhesion molecule-1 (sICAM-1), interleukin-6 (IL-6), endothelin-1 (ET-1), von Willebrand factor (vWF) and soluble tissue factor (sTF). In addition, soluble p-selectin (p-selectin) and vascular endothelial growth factor (VEGF) were measured: the former as a marker of platelet activation, the latter as a potential mediator of TF expression. No significant differences in the levels of blood-borne soluble markers were detected between the patient and control groups except for VEGF and sTF, patients having significantly higher levels of VEGF and sTF than controls (p <0.05). These results suggest plasma soluble tissue factor and VEGF may play a role in the pathogenesis of thrombosis in APS, although the cell of origin of these molecules remains unclear.

Normal expression of cell adhesion molecules in placentae from women with systemic lupus erythematosus and the antiphospholipid syndrome

Pregnant women with active systemic lupus erythematosus (SLE) and/or the antiphospholipid syndrome (APS) are prone to recurrent miscarriage, pre-eclampsia, intrauterine growth restriction and premature delivery. Placental dysfunction may account for these complications yet the mechanisms remain uncertain. Amongst these, an inflammatory response in the placental vasculature could play a role, involving recruitment of neutrophils and platelets and the increased endothelial expression of cell adhesion molecules (CAM), central to the recruitment process. The aim of this study was primarily to investigate CAM expression in the fetoplacental vasculature in women with SLE/APS. Circulating maternal concentrations of soluble CAM were also elucidated. There were no differences in CAM immunostaining in placentae from patients with SLE and/or APS compared with controls. In both patients and controls moderate immunostaining for the intercellular adhesion molecule-1 (ICAM-1) was observed in placental vascular endothelium and mild immunostaining was present in the placental villous stroma. Strong immunostaining for platelet endothelial CAM (PECAM) occured in the placental vascular endothelium whereas P-selectin was mildly expressed in the stem vessel endothelium only. Vascular CAM-1 (VCAM-1) and E-selectin were undetectable in either study or control placentae. In contrast, ICAM-1 and VCAM-1 but not E-selectin, as assessed by immunoassay (ELISA), were elevated in maternal serum from SLE/APS patients compared with controls. This study suggests that upregulation of CAM expression and subsequent activation of neutrophil and/or platelet activity within the placental villous tree is unlikely to be a mechanism by which the adverse pregnancy outcome arises in SLE/APS pregnancies. However, maternal endothelial cell activation (ECA) may play a more important role.

Effect of antioxidants on the occurrence of pre-eclampsia in women at increased risk: a randomised trial

BACKGROUND

Oxidative stress has been implicated in the pathophysiology of pre-eclampsia. This randomised controlled trial investigated the effect of supplementation with vitamins C and E in women at increased risk of the disorder on plasma markers of vascular endothelial activation and placental insufficiency and the occurrence of pre-eclampsia.

METHODS

283 women were identified as being at increased risk of pre-eclampsia by abnormal two-stage uterine-artery doppler analysis or a previous history of the disorder and were randomly assigned vitamin C (1000 mg/day) and vitamin E (400 IU/day) or placebo at 16-22 weeks' gestation. Plasma markers of endothelial activation (plasminogen-activator inhibitor 1 [PAI-1]) and placental dysfunction (PAI-2) were measured every month until delivery. Pre-eclampsia was assessed by the development of proteinuric hypertension. Analyses were done by intention to treat, and in the cohort who completed the study.

FINDINGS

Supplementation with vitamins C and E was associated with a 21% decrease in the PAI-1/PAI-2 ratio during gestation (95% CI 4-35, p=0.015). In the intention-to-treat cohort, pre-eclampsia occurred in 24 (17%) of 142 women in the placebo group and 11 (8%) of 141 in the vitamin group (adjusted odds ratio 0.39 [0.17-0.90], p=0.02). In the cohort who completed the study (81 placebo group, 79 vitamin group), the odds ratio for pre-eclampsia was 0.24 (0.08-0.70, p=0.002).

INTERPRETATION

Supplementation with vitamins C and E may be beneficial in the prevention of pre-eclampsia in women at increased risk of the disease. Multicentre trials are needed to show whether vitamin supplementation affects the occurrence of pre-eclampsia in low-risk women and to confirm our results in larger groups of high-risk women from different populations.

Regulation of the oncogenic activity of BCR-ABL by a tightly bound substrate protein RIN1

RIN1 was originally identified by its ability to physically bind to and interfere with activated Ras in yeast. Paradoxically, RIN1 potentiates the oncogenic activity of the BCR-ABL tyrosine kinase in hematopoietic cells and dramatically accelerates BCR-ABL-induced leukemias in mice. RIN1 rescues BCR-ABL mutants for transformation in a manner distinguishable from the cell cycle regulators c-Myc and cyclin D1 and the Ras connector Shc. These biological effects require tyrosine phosphorylation of RIN1 and binding of RIN1 to the Abl-SH2 and SH3 domains. RIN1 is tyrosine phosphorylated and is associated with BCR-ABL in human and murine leukemic cells. RIN1 exemplifies a new class of effector molecules dependent on the concerted action of the SH3, SH2, and catalytic domains of a cytoplasmic tyrosine kinase.

In vivo association of v-Abl with Shc mediated by a non-phosphotyrosine-dependent SH2 interaction

A necessary downstream element of Abelson murine leukemia virus (Ab-MLV)-mediated transformation is Ras, which can be activated by the phosphotyrosine-dependent association of Shc with the Grb2-mSos complex. Here we show that Shc is tyrosine-phosphorylated and associates with Grb2 in v-Abl-transformed cells, whereas Shc in NIH3T3 cells is phosphorylated solely on serine and is not Grb2-associated. In addition, Shc coprecipitates with P120 v-Abl and P70 v-Abl, which lacks the carboxyl terminus. Surprisingly, a kinase-defective mutant of P120 also binds Shc, demonstrating that Shc/v-Abl association is a phosphotyrosine-independent interaction. Glutathione S-transferase fusion proteins were used to map the interacting domains and showed that Shc from both NIH3T3 and v-Abl-transformed cells binds to the Abl SH2 domain and that P120 v-Abl binds to a region in the amino terminus of Shc. Consistent with these data, a v-Abl mutant encoding only the Gag and SH2 regions was able to bind Shc in vivo. The unique non-phosphotyrosine-mediated binding of Shc may allow direct tyrosine phosphorylation of Shc by v-Abl and subsequent activation of the Ras pathway through assembly of a signaling complex with Grb2-mSos.

Ras complements the carboxyl terminus of v-Abl protein in lymphoid transformation

Abelson murine leukemia virus (Ab-MLV) mutants expressing v-Abl proteins lacking the carboxyl terminus are compromised in the ability to transform lymphoid but not NIH 3T3 cells. This feature correlates with the presence of low levels of phosphotyrosine in lymphoid cells infected with carboxyl-terminal truncation mutants. In contrast, high levels of phosphotyrosine are observed in NIH 3T3 cells infected with wild-type and mutant Ab-MLV. Two downstream targets affected in lymphoid transformants are the GTPase-activating protein and GTPase-activating protein-associated protein p62, molecules which are heavily tyrosine phosphorylated in lymphoid cells transformed by wild-type Ab-MLV but not carboxyl-terminal truncation mutants of Ab-MLV. This difference suggested that signaling mediated via the Ras pathway may be compromised in lymphoid cells expressing the carboxyl-terminal truncation mutants. Consistent with this idea, expression of v-Ha-ras complemented these mutants in primary bone marrow transformation assays and increased transformation frequencies obtained with the Ab-MLV mutants 8- to 20-fold. These data suggest that a biologically important link exists between the carboxyl terminus of v-Abl protein and the Ras pathway. Signals transmitted via this connection may enhance those mediated via other regions of the v-Abl protein and facilitate transformation of primary, nonimmortalized cells such as pre-B lymphocytes.