Role of imaging in surgical decision making in young knee osteoarthrosis

Osteoarthrosis is the most common form of knee arthritis, characterized by pain and discomfort from primarily articular cartilage wear. Traditionally in its end stage, it has been treated with total knee arthroplasty, a permanent process with a life span of ten to fifteen years and challenges with revision. With an increasing longevity and epidemic of obesity that the population is facing, naturally, we are seeing more and more patients with osteoarthrosis at a younger age. This makes it imperative to extend the life of the native knee by conservative measures, injections of steroid, hyaluronic acid, or biologicals and finally a slew of surgical alternatives ranging from joint realignment to partial and total joint replacement. Besides the clinical presentation, decisions are made based on joint alignment, extent and degree of cartilage wear and the status of the subchondral bone. Imaging plays an invaluable role in surgical decision making. In this article, we will discuss how imaging is used in our practice during decision making for the management of the young osteoarthritic knee.

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Prevalence of knee osteoarthrosis is increasing in younger population.

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Surgical treatment of osteoarthrosis at a younger age has its own challenges of need to return to higher levels of physical activity and longer life expectancy.

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Osteoarthrosis is now considered a whole organ dynamic disease.

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Imaging plays an important role in decision making in treatment and management of osteoarthrosis.

Side Strain and Impact Injuries at the Iliac Crest Attachment of Lateral Abdominal Wall Musculature in Cricketers: An Uncommon Injury Pattern

Side strains refer to injuries of the internal/external oblique or the transversus abdominis, commonly at their attachment to the lower four ribs and rarely at their pelvic attachments. Injuries at the rib attachments are well-described while literature on iliac crest attachment injuries is sparse. We report four cricketers who had side strain and direct impact injuries with varying degrees of severity at the iliac crest attachment. The purpose of this article is to describe the anatomy, possible mechanism of injury, and imaging findings in the lateral abdominal wall muscle injuries at the iliac crest, which have not been described previously.

Role of ultrasound-guided decompression in management of mucoid degeneration of the anterior cruciate ligament

OBJECTIVE

To assess the effectiveness of ultrasound-guided decompression in managing symptomatic mucoid degeneration of the anterior cruciate ligament (ACL).

MATERIALS AND METHODS

Retrospective analysis of 55 patients who underwent ultrasound-guided ACL mucoid degeneration decompression between July 2013 and August 2019. Subjective satisfaction scores were gathered immediately post-procedure for all 55 patients; follow-up satisfaction scores (scale of 0-10, 10 being excellent) were gathered telephonically for 46 patients (83.6%) up to 63 months post-procedure. Follow-up duration of each patient was classified as short (1-6 months), intermediate (7-12 months), or long (more than 12 months) post-procedure. Forty-five patients (81.8%) MRI were retrospectively analyzed and classified into cystic (n = 13, 28.9%), mucoid (n = 11, 24.4%), or mucoid-cystic (21, 46.7%) types. Multivariate logistic regression was used to identify associations between follow-up satisfaction score, follow-up duration, patient age, and type of ACL degeneration.

RESULTS

All patients had immediate marked post-procedure improvement, with excellent (>7/10) satisfaction scores. Forty-six of 55 patients were telephonically followed up: 21 (45.6%) short-term interval, 18 (39.1%) intermediate term, and 7 (15.2%) long-term. Thirty (65.22%) patients had excellent and eight (17.4%) patients had average satisfaction scores at follow-up. Eight (17.4%) patients had poor post-procedure satisfaction scores within six months. There were no significant associations between immediate or follow-up satisfaction score and duration of follow-up, age of patient, or type of ACL degeneration.

CONCLUSION

Ultrasound-guided aspiration, fenestration, and injection are an effective, safe, minimally invasive and radiation-free technique for management of mucoid degeneration of ACL with excellent immediate- and long-term results.

Majeed Syndrome: Five Cases With Novel Mutations From Unrelated Families in India With a Review of Literature

OBJECTIVE

Majeed syndrome (MJS) is an autosomal recessive, systemic autoinflammatory disease (SAID) caused by biallelic loss-of-function variants in the LPIN2 gene. It is characterized by early-onset chronic recurrent multifocal osteomyelitis (CRMO), dyserythropoietic anemia, and neutrophilic dermatosis. We analyzed a cohort of uncharacterized Indian patients for pathogenic variants in LPIN2 and other genes associated with SAIDs.

METHODS

We performed whole-exome sequencing (WES) for 1 patient and next-generation sequencing (NGS) targeted gene panel for SAIDs in 3 patients. One patient was a referral from neurology after clinical exome sequencing identified a novel variant in LPIN2. We reviewed the literature for all published studies of mutation-positive MJS patients and have summarized their clinical features and disease-causing variants.

RESULTS

We describe the largest series of patients with MJS outside of the Middle East. All 5 patients are homozygous for novel, possibly pathogenic variants in the LPIN2 gene. Two of these variants are missense substitutions, and 3 are predicted to alter transcript splicing and create a truncated protein. In addition to the classical features of CRMO and anemia, patients exhibited previously unreported features, including abdominal pain, recurrent diarrhea/ear discharge, and erythema nodosum.

CONCLUSION

Patients with MJS may present initially to different specialists, and thus it is important to create awareness in the medical community. In India, consanguinity is a common sociocultural factor in many ethnic communities and an abbreviated NGS gene panel for autoinflammatory diseases should include MJS. The unavailability of interleukin 1 inhibitors in some countries poses a treatment challenge.

0961 Comparison of Clinical Characteristics of Children With Narcolepsy With and Without Sleep Related Movement Disorders

Introduction

Narcolepsy is known to be associated with sleep related movement disorders (SRMD) including periodic limb movement and restless leg syndrome. However, there is paucity of data comparing the clinical characteristics of children with narcolepsy with and without SRMD.

Methods

Retrospective chart review of all children presenting to the sleep clinic for sleep problems between March 2016 to June 2017 was performed. Demographics, sleep intake patient questionnaires and ICD-10 codes for comorbidities and sleep diagnoses were collected. Children with diagnosis of narcolepsy (ICD-10 G47.4) were included in this study. Cohort was divided into 2 groups- with and without co-existing diagnoses of sleep related movement disorders (ICD-10 G47.6). Demographics, presenting symptoms, Epworth sleepiness scores and prevalence of sleep comorbidities were compared using T-test (continuous) and Chi square (categorical). Unadjusted odds ratio was calculated for demographics and presence of SRMD. P value of <0.05 was considered significant.

Results

28 (F=14,50%) children with narcolepsy were included. 25% children were diagnosed with SRMD. Mean (SD) age of children with SRMD presenting to the sleep clinic was 11.14 (5.08) years while mean age (SD) of children without SRMD was 9.52 (3.87) years. Age and race of children with and without SRMD were not statistically different. There was an increased prevalence of females in the group with narcolepsy and SRMD compared to the group without SRMD (86%vs38%, p=0.029). Epworth sleepiness score was not statistically different between the 2 groups. Female gender increased the odds of SRMD in children with narcolepsy (OR:9.75, 0.98- 96.56).

Conclusion

Children with narcolepsy can present with comorbid sleep related movement disorder. Females were more likely to present with associated SRMD compared to males.

Support

None

Household context and psychosocial impact of childhood multidrug-resistant tuberculosis in KwaZulu-Natal, South Africa

SETTING

Referral hospital for drug-resistant tuberculosis (TB) in KwaZulu-Natal, South Africa.

OBJECTIVES

We conducted interviews with primary care givers of children admitted with multidrug-resistant TB (MDR-TB) during a 3-month period in 2015 to identify broader household challenges.

RESULTS

We interviewed 26 care givers, most of whom were women (85%). Most households had been decimated by TB/MDR-TB and human immunodeficiency virus (HIV) infection, and were dependent upon government grants. In 54% of cases, parents were absent due to illness or death, or their whereabouts were not known. The median age of the children treated for MDR-TB was 8 years (range 2-14); 72% were HIV-co-infected. Four themes emerged in the interviews: 1) the psychosocial impact of hospitalisation and separation on the child and the household, 2) the psychosocial impact of MDR-TB on children and 3) on care givers, and 4) the economic hardship of affected households. Children had to contend with multiple diseases and medications, and personal family losses; they faced behavioural, emotional and cognitive difficulties. Care givers were often anxious and concerned about the child's longer-term prospects, while the cost of hospital visits exacerbated the pre-existing economic vulnerability of affected households.

CONCLUSION

The socio-economic impact of childhood MDR-TB reverberates beyond diseased children to their affected households. Enhanced social protection, psychosocial support and treatment literacy would create the foundations for family-centred care.

Pilot evaluation of a second-generation electronic pill box for adherence to Bedaquiline and antiretroviral therapy in drug-resistant TB/HIV co-infected patients in KwaZulu-Natal, South Africa

BACKGROUND

The introduction of Bedaquiline, the first new antimycobacterial drug in over 40 years, has highlighted the critical importance of medication adherence in drug-resistant tuberculosis (DR-TB) treatment to prevent amplified drug-resistance and derive sustained benefit. Real-time electronic dose monitoring (EDM) accurately measures adherence and allows for titration of adherence support for anti-retroviral therapy (ART). The goal of this study was to evaluate the accuracy and acceptability of a next-generation electronic pillbox (Wisepill RT2000) for Bedaquiline-containing TB regimens.

METHODS

Eligible patients were DR-TB/HIV co-infected adults hospitalized for the initiation of Bedaquiline-containing treatment regimens in KwaZulu-Natal, South Africa. A one-way crossover design was used to evaluate levels of adherence and patient acceptance of EDM. Each patient was given a Wisepill device which was filled with ART, Levofloxacin or Bedaquiline over three consecutive weeks. Medication adherence was measured using Wisepill counts, patient-reported seven-day recall, and weekly pill count. An open-ended qualitative questionnaire at the end of the study evaluated participant acceptability of the Wisepill device.

RESULTS

We enrolled 21 DR-TB/HIV co-infected inpatients admitted for the initiation of Bedaquiline from August through September 2016. In aggregate patients were similarly adherent to Bedaquiline (100%) compared to Levofloxacin (100%) and ART (98.9%) by pill count. Wisepill was more sensitive (100%) compared to seven-day recall (0%) in detecting non-adherence events (p = 0.02). Patients reported positive experiences with Wisepill and expressed willingness to use the device during a full course of DR-TB treatment. There were no concerns about stigma, confidentiality, or remote monitoring.

CONCLUSION

In this pilot study patients were highly adherent to Bedaquiline by all adherence measures. However, there was lower adherence to ART by pill count and Wisepill suggesting a possible challenge for adherence with ART. The use of EDM identified significantly more missed doses than seven-day recall. Wisepill was highly acceptable to DR-TB/HIV patients in South Africa, and is a promising modality to support and monitor medication adherence in complex treatment regimens.

Training social workers to enhance patient-centered care for drug-resistant TB-HIV in South Africa

KwaZulu-Natal, South Africa, is the epicenter of an epidemic of drug-resistant tuberculosis (DR-TB) and human immunodeficiency virus (HIV) co-infection, characterized by low rates of medication adherence and retention in care. Social workers may have a unique role to play in improving DR-TB-HIV outcomes. We designed, implemented and evaluated a model-based pilot training course on patient-centered care, treatment literacy in DR-TB and HIV coinfection, patient support group facilitation, and self-care. Ten social workers participated in a 1-day training course. Post-training questionnaire scores showed significant overall gains (P = 0.003). A brief training intervention may be a useful and feasible way to engage social workers in patient-centered care for DR-TB and HIV coinfection.

Provider perspectives on drug-resistant tuberculosis and human immunodeficiency virus care in South Africa: a qualitative case study

OBJECTIVE

To examine influences on health care workers' (HCWs') capacity to deliver health care for multi- and/or extensively drug-resistant tuberculosis (MDR/XDR-TB) and human immunodeficiency virus (HIV) infection in South Africa.

DESIGN

Qualitative data were collected via group and individual interviews with a purposive sample of 17 HCWs at a centralised, tertiary TB facility and analysed using grounded theory.

RESULTS

Four themes were identified: 1) personal infection control practices among HCWs may be weakened by a workplace culture comprising low motivation, disparate risk perceptions and practices across workforce hierarchies, physical discomfort, and problems managing patients with treatment-induced hearing loss. 2) Patient-provider interactions are likely stronger among nurses, and in HIV vs. MDR/XDR-TB service delivery, due to greater attention to patient empowerment and support. Stigma associated with MDR/XDR-TB, considered worse than HIV, may be perpetuated within non-specialised facilities less familiar with MDR/XDR-TB. 3) HCWs who struggle with the daily tedium of MDR/XDR-TB treatment supervision are becoming increasingly supportive of treatment literacy and self-administration. 4) Effective integration of HIV and MDR/XDR-TB services may be impeded by administrative restrictions, workplace norms and provider mindsets.

CONCLUSION

Comprehensive, decentralised management of MDR/XDR-TB and HIV coinfection requires the creation of patient-provider trust and treatment literacy in MDR/XDR-TB programmes, and defying workplace norms that could provoke nosocomial TB exposure and fragmented service provision.

Re-inventing adherence: toward a patient-centered model of care for drug-resistant tuberculosis and HIV

BACKGROUND

Despite renewed focus on molecular tuberculosis (TB) diagnostics and new antimycobacterial agents, treatment outcomes for patients co-infected with drug-resistant TB and human immunodeficiency virus (HIV) remain dismal, in part due to lack of focus on medication adherence as part of a patient-centered continuum of care.

OBJECTIVE

To review current barriers to drug-resistant TB-HIV treatment and propose an alternative model to conventional approaches to treatment support.

DISCUSSION

Current national TB control programs rely heavily on directly observed therapy (DOT) as the centerpiece of treatment delivery and adherence support. Medication adherence and care for drug-resistant TB-HIV could be improved by fully implementing team-based patient-centered care, empowering patients through counseling and support, maintaining a rights-based approach while acknowledging the responsibility of health care systems in providing comprehensive care, and prioritizing critical research gaps.

CONCLUSION

It is time to re-invent our understanding of adherence in drug-resistant TB and HIV by focusing attention on the complex clinical, behavioral, social, and structural needs of affected patients and communities.

Integrating patients' perspectives into integrated tuberculosis-human immunodeficiency virus health care

BACKGROUND

Escalating rates of tuberculosis-human immunodeficiency virus (TB-HIV) co-infection call for improved coordination of TB and HIV health care services in high-burden countries such as South Africa. Patient perspectives, however, are poorly understood in the context of current integration efforts.

METHOD

Under a qualitative research framework, we interviewed 40 HIV-positive adult TB patients and eight key-informant health care workers across three clinics in KwaZulu-Natal Province to explore non-clinical and non-operational aspects of TB-HIV health care.

FINDINGS

Qualitative analysis highlighted critical social and ethical considerations for the concurrent delivery of TB and HIV care. Co-infected patients navigating between TB and HIV programs are exposed to missed opportunities for TB and HIV service integration, fragmented or vertical care for their dual infections and contrasting experiences within TB and HIV clinics. These intersecting issues appear to affect patients' health-related decisions, particularly nondisclosure of HIV status to non-HIV health care workers and their preferences for integrated health care.

CONCLUSION

Our study highlights the imperative to address service fragmentation, HIV medical confidentiality and provider mistrust within the health care system, and the cultural differences associated with TB and HIV disease control.

Case series of the long-term psychosocial impact of drug-resistant tuberculosis in HIV-negative medical doctors

BACKGROUND

Health care workers (HCWs) are at greater risk for tuberculosis (TB), including multidrug-resistant TB (MDR-TB), compared to the general population. The psychosocial impact of nosocomial TB on HCWs has received little attention in the literature.

METHODS

A retrospective medical record review from 1999 to 2003 found 15 HCWs who were treated for drug-resistant TB at a specialist hospital in South Africa. Five human immunodeficiency virus (HIV) negative doctors with no predisposing factors for drug resistance are included in this case series. We collectively present their clinical case histories based on medical records from 2000 to 2005, and explore the long-term psychosocial impact of TB from interviews conducted in 2009.

RESULTS

Four doctors had primary MDR-TB and one had primary resistance to multiple first-line drugs. Time from symptom onset to commencement of effective treatment ranged from 8 to 39 weeks. Time for bacteriological confirmation of drug-resistant TB ranged from 6 to 24 weeks. All were cured within 3 years of initial presentation. Content analysis of follow-up interviews revealed five main themes: 1) prolonged morbidity, 2) psychological impact, 3) poor infection control, 4) weak support structures and 5) attrition from the field.

CONCLUSION

Themes emergent from this case series encourage prioritisation of TB infection control education and practice to minimise HCW morbidity and prevent HCW attrition from high-burden resource-constrained settings.

Adherence to treatment for latent tuberculosis infection: systematic review of studies in the US and Canada

BACKGROUND

There is renewed attention to the critical role of successfully treating latent tuberculosis infection (LTBI) in reducing the overall impact of tuberculosis (TB). However, levels of treatment adherence are consistently low in industrialized countries such as the United States and Canada.

OBJECTIVE

A systematic review of studies in the US and Canada was undertaken to analyze measurement of adherence to treatment of LTBI (TLTBI), TLTBI completion rates, predictors of TLTBI adherence and TLTBI adherence interventions.

METHODS

PUBMED, MEDLINE and PsycINFO electronic databases were searched for quantitative studies published between 1997 and 2007. Full texts of articles were reviewed for data abstraction and studies were critically examined for their methodology and rigor. The present review presents outcomes from 78 studies.

RESULTS

Adherence and completion rates of TLTBI are suboptimal across high-risk groups, regardless of regimen. Associations between adherence and patient factors, clinic facilities or treatment characteristics were found to be inconsistent across studies. Several adherence interventions have been developed to improve TLTBI adherence in the US and Canada; however, no single intervention has shown consistent effectiveness.

CONCLUSION

LTBI must be effectively treated if the goal of TB elimination is to be realized. Consistently employing tools for measuring and improving adherence is fundamental. Identifying barriers to adherence and treatment completion will facilitate the development of effective, appropriate interventions. A 'one-size-fits-all' approach to treatment for TLTBI adherence is not likely to succeed across all settings. Innovative approaches can inspire future interventions and suggest solutions for the current problems facing LTBI programs and their patients.

Iodinated contrast media and their adverse reactions

Cross-use of technology between nuclear medicine and radiology technologists is expanding. The growth of PET/CT and the increasing use of intravenous contrast agents during these procedures bring the nuclear medicine technologist into direct contact with these agents and their associated complications. A basic understanding of the occurrence, risk factors, clinical features, and management of these procedures is of increasing importance to the nuclear medicine technologist. After reading this article, the technologist will be able to list the factors that increase the risk of contrast reactions; understand ways to minimize the occurrence of contrast reactions; and develop a plan to identify, treat, and manage the reactions effectively.

HIV testing and disclosure: a qualitative analysis of TB patients in South Africa

In South Africa, more than 60% of TB patients have HIV co-infection. Voluntary counseling and testing (VCT) is critical to effective HIV prevention, and TB facilities are optimal venues for delivery of these services. This study employed qualitative research methods to explore the decision-making processes for HIV testing and serostatus disclosure by 21 patients hospitalized with multi/extensively-drug resistant TB (M/XDR-TB) in Durban, KwaZulu Natal. Data collected from in-depth interviews characterized 3 broad themes: HIV testing history, experiences and perceptions of stigma and disclosure, and the relationship between TB and HIV/AIDS. Fear of AIDS-related stigma, the singular stress of TB infection, the absence of partner's consent, asymptomatic or incurable disease, and uncertainty about subsequent eligibility for antiretroviral treatment while still receiving TB treatment were identified as potential barriers to the uptake of VCT. HIV serostatus disclosure was impeded by the felt stigma of a 'discreditable' infection, manifested by social rejection and discrimination. The public disclosure of TB illness helped relieve some co-infected patients' overall burden of stigma through a process of 'covering'. HIV prevention [corrected] measures such as VCTare likely to be more effective within TB facilities if greater sensitivity is paid to TB patients' specific social issues and perceptions. These patients are not only at greater risk for HIV co-infection but also for experiencing the double stigma of TB and HIV/AIDS.

Cerebral perfusion changes in older delirious patients using 99mTc HMPAO SPECT

BACKGROUND

Prior studies describe variable cerebral blood flow changes in delirium. This study aims to investigate cerebral blood flow changes in older hospitalized patients with delirium, the population in which most cases of delirium occur.

METHODS

Participants included hospitalized general medical patients aged 65 years and older with documented delirium and no relevant medical conditions or preexisting abnormalities on neuroimaging prospectively studied using 99mTc HMPAO single photon emission computed tomography (SPECT) scans obtained during and after resolution of delirium. Twenty-two patients enrolled in the study, of whom six completed both scans. All participants underwent neuropsychological assessment immediately prior to SPECT scanning. SPECT images were compared across all participants during delirium; for patients completing paired scans, within-patient comparisons were made.

RESULTS

Visual assessment of SPECT scans revealed perfusion abnormalities in frontal (5 participants) or parietal regions (6 participants); scans were normal in 11 participants (50%). Region-of-interest analysis identified reduced blood flow (p <.01) in the left inferior frontal, right temporal, right occipital, and pontine regions. Analysis of paired scans revealed reversible abnormalities in three participants (p <.001), with decreased right parietal perfusion in two participants and increased left parietal perfusion in one participant.

CONCLUSIONS

The results of this study of a small group of general medical patients are suggestive that frontal or parietal cerebral perfusion abnormalities occur in delirium, and these findings need to be confirmed by future, larger studies. These results may help to improve basic understanding of delirium pathophysiology, to identify long-term changes, and to evaluate response to treatment over time.

Three-dimensional Anatomy of the Left Central Veins: Implications for Dialysis Catheter Placement

PURPOSE

To define the three-dimensional anatomy of the left central veins and the implication for left-sided dialysis catheter placement.

MATERIALS AND METHODS

Images from 30 consecutive patients undergoing computed tomography (CT) pulmonary angiography were reconstructed to depict the central venous anatomy. The reconstructed images were analyzed for parameters that could influence dialysis catheter placement. In particular, the cross-sectional diameters of the left brachiocephalic vein were measured, as well as the angulation between the left internal jugular vein and brachiocephalic vein, the angulation between left brachiocephalic vein and superior vena cava, and the angulation of the left brachiocephalic vein in the axial plane as it crosses the mediastinum.

RESULTS

The cross-sectional diameters of the left brachiocephalic vein did not change significantly as it traversed the mediastinum. The mean cross-sectional diameters were 11 (+/-5.2) x 12 (+/-5.1) mm for the peripheral, 13 (+/-5.0) x 13 (+/-4.8) mm for the mid, and 13 (+/-4.6) x 14 (+/-4.5) mm for the central left brachiocephalic vein. The angulation between the left internal jugular and brachiocephalic vein measured 117 degrees (+/-11), the angulation between the left brachiocephalic vein and the superior vena cava measured 116 degrees (+/-7), and the angulation of the left brachiocephalic vein as it traverses the aorta and left brachiocephalic artery measured 106 degrees (+/-9).

CONCLUSIONS

A sharp angulation of the left brachiocephalic vein as it drapes over the aorta or arch vessels is a common anatomic finding. This angulation is not apparent on frontal projection radiographs or venograms. A hemodialysis catheter torqued over this angulation could contact the vessel wall and lead to endothelial irritation. Further study may help define whether this contributes to the higher complication rates associated with left-sided catheters.

Fractures of the calcaneus: a review with emphasis on CT

The calcaneus is the most commonly fractured tarsal bone and accounts for about 2% of all fractures. Advances in cross-sectional imaging, particularly in computed tomography (CT), have given this modality an important role in identifying and characterizing calcaneal fractures. Fracture characterization is essential to guide the management of these injuries. Calcaneal fractures have characteristic appearances based on the mechanism of injury and are divided into two major groups, intraarticular and extraarticular. Most calcaneal fractures (70%-75%) are intraarticular and result from axial loading that produces shear and compression fracture lines. Of the two major systems for classifying intraarticular fractures-Hannover and Sanders-the latter is used most often and is helpful in treatment planning and determining prognosis. Extraarticular fractures account for about 25%-30% of calcaneal fractures and include all fractures that do not involve the posterior facet. The article describes in detail calcaneal anatomy, mechanism of calcaneal injuries and their associated fracture patterns, CT features of intra- and extraarticular fractures, and management implications. Familiarity with calcaneal anatomy and fracture patterns is essential for radiologists to guide the treating physicians.

Chest Radiograph as a Triage Tool in the Imaging-Based Diagnosis of Pulmonary Embolism

OBJECTIVE

The purpose of this study was to evaluate whether using a chest radiograph to triage patients being imaged for pulmonary embolism (PE) with pulmonary CT angiography (CTA) or ventilation-perfusion scintigraphy resulted in fewer indeterminate imaging results.

CONCLUSION

Chest radiograph can be a valuable triage tool in deciding an appropriate technique for imaging PE, and can yield more definitive diagnoses.

Expression of von Hippel Lindau (pVHL) protein in placentae from normal pregnant women and women with preeclampsia

The hypoxia inducible transcription factors, HIF-1alpha and -2alpha proteins, are overexpressed in placentae from women with preeclampsia (Biol Reprod 2001;64:499-506; Biol Reprod 2001;64:1019-1020). Normally, these proteins are regulated in an oxygen-dependent manner being rapidly degraded by the ubiquitin-mediated proteasomal pathway. Recent studies have shown that the tumor suppressor protein, von Hippel Lindau (VHL), targets HIF for ubiquitinylation under nonhypoxic conditions. The objectives of the present work were: (1) to investigate VHL protein expression in normal pregnant (NP), preeclamptic (PE), and preterm (without PE) placentae, (2) to test whether VHL protein is hypoxia inducible in term and first trimester placental villous explants, and (3) to analyze the ontogeny of VHL protein expression in the human placenta. To begin evaluating the potential contribution of VHL to HIF overexpression in preeclamptic placentae, we analyzed the levels of the VHL protein in both normal and preeclamptic placentae (n=7 each). We hypothesized a deficiency of VHL protein in preeclamptic placentae. Eight biopsy sites were tested in each placenta and protein extracts were made. Western analysis was performed using VHL specific antibodies. Human renal adenocarcinoma (ACHN) cell extracts and extracts from COS-7 cells transfected with a VHL expression vector were used as positive controls. In a total of 112 biopsy sites that were analyzed (56 each for normal and preeclamptic placentae), the composite densitometry ratios (PE/NP) for the long (28 kDa) and short (19 kDa) forms of VHL were 1.09+/-0.2 and 1.16+/-0.11, respectively (both p=NS vs 1.0). A ratio of 1.0 indicates equal expression by preeclamptic and normal placentae. The same placentae exhibited composite densitometry (PE/NP) ratios of 1.97+/-0.23 and 1.68+/-0.20 for HIF-1alpha and -2alpha proteins, respectively (both p<0.05 vs 1.0). In a separate analysis, the protein expression of the short form of VHL was also comparable among NP, PE and preterm (n=6) placentae. VHL immunoreactivity was localized to cells within the basal plate and the syncytiotrophoblast. Despite induction of HIF proteins by hypoxia in first and term villous explants, there was no significant upregulation of VHL proteins. Finally, the expression of both the short and long forms of VHL protein decreased with gestational age (both p<0.05 by ANOVA), and in villous tissue from first trimester placentae VHL immunoreactivity was predominantly localized to the cytotrophoblast. These results suggest that (1) deficiency of VHL protein does not account for HIF-alpha overexpression in preeclamptic placentae, (2) VHL protein is not regulated by hypoxia in either first trimester or term placental villous explants, and (3) VHL protein expression in the placenta decreases as a function of gestational age.

Evidence for the functional activity of hypoxia-inducible transcription factors overexpressed in preeclamptic placentae

Placentas from women with preeclampsia overexpress the hypoxia-inducible transcription factor proteins, HIF-1alpha and -2alpha (Rajakumar 2001, Biol Reprod 64; p499-506 and p1019-1020). As a first step in evaluating whether HIF-alpha overexpressed in preeclamptic placentae is capable of transactivation, we tested its ability to bind to the DNA hypoxia response element (HRE). Six pairs of normal and preeclamptic placentae obtained by cesarean section were investigated. Three biopsy sites per placenta were analyzed. We first confirmed HIF-1alpha protein overexpression in the preeclamptic placentae using Western analysis. The ratios of the arbitrary densitometry units for HIF-1alpha protein from the preeclamptic and normal placentae (PE/NP) in the three biopsy sites were: 1.9 +/- 0.3, 1.7 +/- 0.2 and 1.8 +/- 0.2, each p < 0.05 vs 1.0. (A ratio of >1.0 indicates that HIF-1alpha protein expression in placentas of women with PE exceeds that in placentas of NP women.) Conventional methods for extracting nuclear proteins and subsequent analysis by electrophoretic mobility shift assay were not suited for the frozen, archived samples (data not shown). Therefore, we employed DNA affinity chromatography using a biotinylated oligonucleotide representing the HRE of the erythropoietin gene coupled to streptavidin-coated Dynabeads. The HRE-bound proteins were then characterized by Western blot analysis. The PE/NP ratios of HRE-bound HIF-1alpha in the three biopsy sites from the six pairs of normal and preeclamptic placentae were 1.7 +/- 0.2, 2.1 +/- 0.4 and 2.4 +/- 0.5, each p < 0.05 vs 1.0. Having established DNA-binding potential at least in vitro, we subsequently analyzed three proteins that have been shown to be regulated by HIF-alpha as downstream, molecular markers of HIF-1alpha activity in vivo. VEGF receptor Flt-1 and Flk-1 play key roles in angiogenesis. Tyrosine hydroxylase is the rate-limiting enzyme in catecholamine synthesis. All three genes contain functional HRE in their promoter sequences. Total proteins were extracted from the same biopsy samples that were used for total and HRE-bound HIF-1alpha. Using specific antibodies we performed Western analysis and the levels of these three proteins were quantitated. The Flt-1 and tyrosine hydroxylase proteins were significantly higher, and Flk-1 significantly lower in placentae from preeclamptic compared to normal pregnancies. In summary, HIF-1alpha protein overexpressed in preeclamptic placentae is capable of binding to its DNA recognition sequence in vitro, and modulates gene expression in vivo.

Benzodiazepine receptor distribution in severe intractable tinnitus

Tinnitus affects nearly 50 million people in the United States, with a minority demonstrating marked functional impairment. Alterations of gamma aminobutyric acid (GABA) neuronal function and benzodiazepine receptor (BZR) function in particular have been implicated in the pathophysiology of severe, chronic tinnitus. The purpose of our study was to evaluate the distribution of BZR in the brain using 123I-iomazenil single-photon emission computed tomography (SPECT) imaging in patients with severe, intractable central tinnitus. Six patients with severe intractable tinnitus received a bolus and constant infusion of 123I-iomazenil intravenously over 7 hours with SPECT and magnetic resonance imaging of the brain. After magnetic resonance imaging coregistration, standardized regions of interest were placed over the cerebellar, frontal (control), superior temporal, hippocampal, and thalamic regions bilaterally on (SPECT) images. Venous blood samples were drawn at specified intervals to determine equilibrium distribution volumes (V3') for each of the regions. Variation in V3' values in homotypic regions were calculated using a Wilcoxon signed rank test. Twelve normal control subjects were compared to the study subjects using statistical parametric mapping. Comparison of homotypic brain regions showed statistically significant asymmetry in the V3' data in the superior temporal cortex (p = .03 for both). No statistically significant difference was noted in any of the other regions studied. Comparison of the group of study subjects to healthy controls revealed an insignificant trend toward reduction in BZR density in the frontal lobes bilaterally (p = .000) and a reduction in the cerebellum (p = .045). Current understanding suggests GABA receptors and the temporal lobe system as the final common pathway. This pilot study suggests possible alterations on 123I-iomazenil SPECT imaging and the need for larger studies.

Impaired oxygen-dependent reduction of HIF-1alpha and -2alpha proteins in pre-eclamptic placentae

Pre-eclamptic (PE) placentae overexpress hypoxia inducible transcription factors-1alpha and -2alpha proteins (Biol. Repro. 64: 499-506, 2001; Ibid 1019-1020). Possible explanations include (a) impaired oxygen-dependent reduction, and/or (b) enhanced sensitivity to reduced oxygen. After 18 h equilibration under 21 per cent O(2) atmosphere, we subjected villous explants prepared from placentae of normal pregnant (NP) and pre-eclamptic (PE) women (n=8 each) to 4h of hypoxia (2 per cent oxygen), and then studied the disappearance of HIF-1alpha and -2alpha proteins during subsequent oxygenation over 90 min (21 per cent oxygen). The disappearance of these HIF proteins as assessed by Western analysis was significantly impaired in the pre-eclamptic tissues. Even after 18h equilibration under a 21 per cent O(2) atmosphere, and then a further 4h at 21 per cent O(2), HIF-1alpha and -2alpha protein expression remained increased in villous explants from PE women (both P< 0.04 vs NP). To address whether chronic hypoxia per se (which is believed to exist in the pre-eclamptic placenta) might contribute to these findings, we subjected villous explants from normal placentae (n=6) to 18 h preincubation under 2 per cent or 21 per cent oxygen prior to subsequent incubation for 4h at 2 per cent oxygen and then 90 min at 21 per cent oxygen. The time course of disappearance of HIF proteins during oxygenation was similar irrespective of the 2 per cent or 21 per cent preconditioning. To evaluate oxygen sensitivity, we exposed villous explants from NP and PE women (n=6 each) to different oxygen atmospheres for 4h and measured HIF protein induction. Although the data showed a significant inverse relationship between HIF expression and oxygen concentration, there was no significant difference between the slopes of this relationship for the two groups of women. We conclude that villous explants from PE placentae fail to adequately downregulate HIF protein expression upon oxygenation. This abnormality may contribute to their overexpression in vivo.

Single fetal demise in a twin gestation: umbilical vein thrombosis

BACKGROUND

Single fetal demise in a twin pregnancy is a rare event, the common causes being twin-twin transfusion syndrome, chromosomal or congenital anomalies and abnormalities of the umbilical cord and placenta. Umbilical vein thrombosis is a very rare cause of single fetal demise in twins.

CASE

Three days after a reassuring biophysical profile, a 40-year-old primigravida with twin pregnancy presented at 38 weeks' gestation in early labor when demise of 1 of the twins was recognized. She underwent a cesarean section for arrest of labor, delivering twin A, a stillborn female weighing 2, 360 g and twin B, a liveborn male weighing 2,200 g. Umbilical vein thrombus was noted in twin A.

CONCLUSION

Umbilical vein thrombosis is a rare and sudden cause of fetal demise.

Benzodiazepine receptor deficiency and tinnitus

As regards the symptom of a predominantly central tinnitus of the severe, disabling type, it has been hypothesized that a deficiency in the benzodiazepine receptor exists in the medial temporal lobe system of brain and is directly related to affect impairments including anxiety, stress, depression, and fear. This hypothesis has been investigated with single-photon emission computed tomography using the benzodiazepine radioligand 123I Iomazenil. Visual analysis revealed preliminary results of diminished benzodiazepine-binding sites in the medial temporal cortex of all patients with severe tinnitus (N = 6), a finding that is consistent with the hypothesis implicating GABAergic mechanisms in the pathophysiology of the disorder. An abnormal gamma-aminobutyric acid--A benzodiazepine receptor density may be an objective neurochemical measure of the severity of a central-type tinnitus and a rationale for treatment. Clinical correlation with the history, clinical course of the patient, and stress questionnaire are presented.

Oral gastrografin in neonates: a note of caution

Hyperosmolar feeds are known to increase gastrointestinal permeability, predisposing to absorption of toxins. They are also associated with necrotising enterocolitis (NEC) in neonates. A case of a neonate with suspected NEC who died following Gram-negative septicaemia possibly related to oral gastrografin is reported. Hyperosmolarity of gastrografin may have caused complete loss of mucosal integrity in the compromised bowel leading to Gram-negative septicaemia.

Alterations in ovine myometrial beta-adrenergic cascade do not mediate tachyphylaxis to ritodrine

The purpose of this study was to determine in vivo the dose response relationship between beta-adrenergic receptor (BAR) agonist concentration and various elements of the BAR cascade: receptor density, hormone-stimulable adenylyl cyclase activity, and contraction inhibition. A previously described, chronically-catheterized ovine model was used. Ritodrine was infused continuously over 24 h in 22 mixed-breed sheep. Each animal received a single, constant infusion rate. Myometrial biopsies were obtained before and after the drug infusions. BAR density was determined using tritiated dihydroalprenolol. Adenylyl cyclase activity was determined using the Gilman competitive protein-binding assay. Intermittent oxytocin boluses were given into the maternal aorta and contractile response was determined. Infusion rates of 0.06-4.0 micrograms/kg/min yielded steady-state ritodrine serum concentrations of 5-168 ng/ml. No significant correlation was found between the ritodrine concentration and the magnitude of decrease in BAR density. Significant correlations existed, however, between the ritodrine concentration and both the magnitude of decrease in adenylyl cyclase activity and the loss of contraction inhibition. There was no correlation noted between the BAR cascade alterations and the loss of contraction inhibition. Despite significant reductions in receptor density (down regulation) and dose-related reductions in hormone-stimulable adenylyl cyclase activity (uncoupling), ritodrine at low concentrations was still able to inhibit oxytocin-induced contractions, i.e., tachyphylaxis did not occur. Tachyphylaxis appeared to correlate only with the serum ritodrine concentration. Hence, alterations in the BAR cascade do not necessarily equate with a loss of end-organ response (tachyphylaxis). Previous concepts based on in vitro studies about the interaction of the BAR agonist with its receptor, the subsequent generation of intracellular messengers, and the resultant end-organ response may not apply in the intact animal.