Availability of medical abortion medicines in eight countries: a descriptive analysis of key findings and opportunities

BACKGROUND

In recent years a growing number of manufacturers and medical abortion products have entered country markets and health systems, with varying degrees of quality and accessibility. An interplay of factors including pharmaceutical regulations, abortion laws, government policies and service delivery guidelines and provider's knowledge and practices influence the availability of medical abortion medicines. We assessed the availability of medical abortion in eight countries to increase understanding among policymakers of the need to improve availability and affordability of quality-assured medical abortion products at regional and national levels.

METHODS

Using a national assessment protocol and an availability framework, we assessed the availability of medical abortion medicines in Bangladesh, Liberia, Malawi, Nepal, Nigeria, Rwanda, Sierra Leone and South Africa between September 2019 and January 2020.

RESULTS

Registration of abortion medicines-misoprostol or a combination of mifepristone and misoprostol-was established in all countries assessed, except Rwanda. Mifepristone and misoprostol regimen for medical abortion was identified on the national essential medicines list/standard treatment guidelines for South Africa as well as in specific abortion care service and delivery guidelines for Bangladesh, Nepal, Nigeria, and Rwanda. In Liberia, Malawi, and Sierra Leone-countries with highly restrictive abortion laws and no abortion service delivery guidelines or training curricula-no government-supported training on medical abortion for public sector providers had occurred. Instead, training on medical abortion was either limited in scope to select private sector providers and pharmacists or prohibited. Community awareness activities on medical abortion have been limited in scope across the countries assessed and where abortion is broadly legal, most women do not know that it is an option.

CONCLUSION

Understanding the factors that influence the availability of medical abortion medicines is important to support policymakers improve availability of these medicines. The landscape assessments documented that medical abortion commodities can be uniquely impacted by the laws, policies, values, and degree of restrictions placed on service delivery programs. Results of the assessments can guide actions to improve access.

In-country availability of medical abortion medicines: a description of the framework and methodology of the WHO landscape assessments

BACKGROUND

Availability of quality-assured medical abortion medicines plays a crucial role in providing comprehensive abortion care. However, access to these medicines is still restricted for many abortion seekers. Increasing availability of affordable, quality-assured mifepristone and misoprostol is important to improve access to safe medical abortion services. Driven by the outcomes of a global consultation hosted by the World Health Organization and the Swedish International Development Cooperation Agency in 2018, we decided to holistically examine access to medical abortion medicines from supply to demand. The overarching principle of the national landscape assessments was to generate evidence to support policy dialog and policymaking that is contextual to the needs of the country. This paper aims to describe the framework and methodological approach used in the World Health Organization landscape assessments of medical abortion medicines at country-level.

METHODS

A country assessment protocol was developed to guide the methodology of the World Health Organization landscape assessments. The assessment protocol included adaptation of an existing availability framework, an online desk review and literature review for existing data available for the country of interest, country-level key informant interviews, and analysis of the data to identify barriers and opportunities to improve medical abortion availability.

CONCLUSION

The availability framework and methodology will allow the identification of key barriers that limit readiness of medical abortion medicines, and the development of opportunities to overcome those barriers. The national landscape assessments will provide directions for future investments and offer guidance for policy and programming on medical abortion care.

New onset diabetes after kidney transplantation is associated with increased mortality-A retrospective cohort study

OBJECTIVE

Clinical outcomes in individuals with new onset diabetes after transplantation (NODAT) and the optimal treatment for this complication are poorly characterized. This study was intended to better define these issues.

METHODS

Patients who underwent kidney transplantation and did not have diabetes prior to transplantation were included in the study. Clinical outcomes were compared between those who developed NODAT and those who did not. In those who developed NODAT, oral therapy was compared with insulin based therapy.

RESULTS

A total of 266 kidney transplant recipients were included, of which 71 (27%) developed NODAT during the time of the follow-up. Using Cox multivariate analysis adjusted for age and gender, hazard ratio for overall mortality among patients with NODAT versus those without NODAT was 2.69 (95% CI 1.04-7.01). Among patients who developed NODAT, 29 patients (40%) were treated with an insulin-based regimen. At the end of follow-up, no difference was found in mean HbA1c, and therapy regimen was not associated with greater mortality.

CONCLUSIONS

New onset diabetes in kidney transplanted patients is associated with increased mortality compared with kidney transplanted patients without NODAT.

Hearing threshold shifts among military pilots of the Israeli Air Force

Background

Military aviators are potentially at risk for developing noise-induced hearing loss. Whether ambient aircraft noise exposure causes hearing deficit beyond the changes attributed to natural ageing is debated. The aim of this research was to assess changes in hearing thresholds of Israeli Air Force (IAF) pilots over 20 years of military service and identify potential risk factors for hearing loss.

Methods

A retrospective cohort analysis was conducted of pure-tone air conduction audiograms of pilots, from their recruitment at 18 years of age until the last documented medical check-up. Mean hearing thresholds were analysed in relation to age, total flight hours and aircraft platform. Comparisons were made to the hearing thresholds of air traffic controllers (ATCs) who were not exposed to the noise generated by aircraft while on duty.

Results

One hundred and sixty-three pilots were included, with flying platforms ranging from fighter jets (n=54), combat helicopters (n=27), transport helicopters (n=52) and transport aircraft (n=30). These were compared with the results from 17 ATCs. A marked notch in the frequency range of 4–6 kHz was demonstrated in the mean audiograms of all platforms pilots, progressing with ageing. Hearing threshold shifts in relation to measurements at recruitment were first noted at the age of 30 years, particularly at 4 kHz (mean shift of 2.97 dB, p=0.001). There was no statistical association between flying variables and hearing thresholds adjusted for age by logistic regression analysis.

Conclusions

The audiometric profile of IAF pilots has a pattern compatible with noise exposure, as reflected by characteristic noise notch. However, no flight variable was associated with deterioration of hearing thresholds, and no significant difference from non-flying controls (ATCs) was seen.

From pituitary adenoma to pituitary neuroendocrine tumor (PitNET): an International Pituitary Pathology Club proposal

The classification of neoplasms of adenohypophysial cells is misleading because of the simplistic distinction between adenoma and carcinoma, based solely on metastatic spread and the poor reproducibility and predictive value of the definition of atypical adenomas based on the detection of mitoses or expression of Ki-67 or p53. In addition, the current classification of neoplasms of the anterior pituitary does not accurately reflect the clinical spectrum of behavior. Invasion and regrowth of proliferative lesions and persistence of hormone hypersecretion cause significant morbidity and mortality. We propose a new terminology, pituitary neuroendocrine tumor (PitNET), which is consistent with that used for other neuroendocrine neoplasms and which recognizes the highly variable impact of these tumors on patients.

Are Thyroid Hormone Values Obtained in Hospitalized Elderly Patients Reproducible? - A Cohort Study

It is unclear whether TSH should be obtained in elderly hospitalized patients as several factors associated with hospitalization influence these levels, which may not truly represent the thyroid status of the individual. All patients≥65 years old hospitalized in a geriatric ward in the years 2012-2014 had TSH measured irrespective of the cause for hospitalization. All patients in whom TSH levels were performed in an ambulatory setting 2-12 months following hospitalization were identified and these TSH levels were correlated with levels recorded during hospitalization. Factors influencing TSH reproducibility were identified through review of patients' medical records. Of 562 patients hospitalized during the study period, 198 had repeat ambulatory TSH measurements during follow-up. The Katz Index of Independence was higher (9.43±2.98 vs. 8.43±3.67 p=0.002) and cerebrovascular disease was less prevalent (15.6 vs. 25.2% p=0.014) in those who had a repeat TSH measurement compared with those who did not, but other baseline characteristics and TSH levels on admission were similar. Ambulatory TSH values were significantly correlated with those obtained during hospitalization (correlation coefficient=0.677), irrespective of baseline systolic blood pressure, cause of hospitalization, or admission albumin levels. Mean TSH difference between in-hospital and ambulatory was 0.65±2.36 mIU/l and in more than 94% of cases TSH values differed by less than 2 mIU/l between the 2 measurements. In hospitalized patients≥65 years old, TSH levels are highly concordant with ambulatory values. TSH obtained during hospitalization may be used for making treatment decisions and has clinical utility in this population.

Blood pressure response to medical treatment in the emergency department - a retrospective cohort study

OBJECTIVES

It is unclear whether blood pressure (BP) without target organ damage should be decreased in patients in the emergency department (ED). It is also uncertain whether any certain class of medications has an advantage over the other in this setting. This study addressed both these questions.

METHODS

In this retrospective cohort study, all patients attending a tertiary care ED with elevated BP were evaluated. All patients with target organ damage as well as those with significant active co-morbidities, such as myocardial ischemia, were excluded. Baseline characteristics and response of BP to therapy were compared between those treated and untreated in the ED. In addition, BP response to therapy was compared between different classes of antihypertensive medications.

RESULTS

Overall, 438 patients were included in the final analysis (62% female), of which 275 (63%) were treated in the ED. Antihypertensive medications were more commonly prescribed in the ED for those with higher systolic and diastolic BP, but other baseline characteristics were similar between the two groups. Only systolic BP significantly decreased in those treated with antihypertensive medications compared with those untreated. The most commonly used classes were angiotensin converting enzyme inhibitors (ACEis) and calcium channel blockers (CCBs). Use of either of these drug classes was not associated with a significant decrease in either systolic or diastolic BP compared with the use of other drug classes.

CONCLUSIONS

Antihypertensive drug therapy is more commonly prescribed in the ED in individuals with both elevated systolic and diastolic BP, but leads to a significant decrease only in systolic BP. Use of either ACEis or CCBs is not associated with a significant decrease in either systolic or diastolic BP compared with other drug classes.

The management of pre-hypertension in primary care: Is it adequate?

BACKGROUND

Pre-hypertension (pHT) is frequently diagnosed in the primary care setting, but its management by primary care physicians (PCPs) is not well characterized.

METHODS

All individuals aged 30-45 years who were insured by Clalit Health services in the Tel Aviv district and had their blood pressure (BP) measured from January 2006 to December 2010 were evaluated. Individuals were divided into three groups based on their initial BP value: optimal (< 120/80 mmHg), normal (systolic BP 120-129 or diastolic 80-84 mmHg) and borderline (130-139/85-89 mmHg). Groups were compared regarding clinical and laboratory follow-up performed by their PCP.

RESULTS

Of the 20,214 individuals included in the study, 6576 (32.5%) had values in the pHT range. Of these, 2126 (32.3% of those with pHT) had BP values defined as "borderline" and 4450 (67.6% of those with pHT) had BP values defined as "normal". The number of follow-up visits by the PCP and repeat BP measurement were similar in those with "optimal" BP and pHT. A third and fourth BP measurement were recorded more frequently in those with pHT. In those with pHT, there were more recorded BP measurements than in those with borderline BP (3.35 ± 3 vs. 3.23 ± 2.6), but the time from the initial to the second measurement and a record of a third and fourth measurement were the same in the two groups.

CONCLUSION

Identification of pHT does not lead to a significant change in follow-up by PCPs, irrespective of BP values in the pHT range.

[18F]FDG-PET/CT for the diagnosis of patients with fever of unknown origin

BACKGROUND AND AIMS

The diagnosis of patients with fever of unknown origin (FUO) remains a challenging medical problem. We aimed to assess the diagnostic contribution of 18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET)/computed tomography (CT) for the evaluation of FUO.

METHODS

We performed a 4-year retrospective single-center study of all hospitalized patients that underwent FDG-PET/CT for evaluation of FUO. The final diagnosis of the febrile disease was based on clinical, microbiological, radiological and pathological data available at the final follow-up. Predictors for a contributory exam were sought.

RESULTS

One hundred and twelve patients underwent FDG-PET/CT for the investigation of FUO in the years 2008-2012 and were included in the study. A final diagnosis was determined in 83 patients (74%) and included: infectious disease in 49 patients (43%), non-infectious inflammatory disease in 17 patients (16%), malignancies in 15 patients (14%), other diagnoses in 2 patients (1.7%), FUO resolved with no diagnosis and no evidence of disease during a 6-month follow-up in 23 patients (20%), and death with fever and with no diagnosis in 6 patients (5%). Seventy-four FDG-PET/CT studies (66%) were considered clinically helpful and contributory to diagnosis (46% positive contributory value and 20.5% contributory to exclusion of diagnosis). PET/CT had a sensitivity of 72.2%, a specificity of 57.5%, a positive predictive value (PPV) of 74.2% and a negative predictive value (NPV) of 53.5%. On multivariable analysis, significant predictors of a positive PET/CT contributory to diagnosis were a short duration of fever and male gender.

CONCLUSIONS

PET/CT is an important diagnostic tool for patients with FUO.

The therapy of Cushing's disease in adults and children: an update

Cushing's disease (CD) is a rare endocrine disorder resulting from excessive production of adrenocorticotrophin hormone by a pituitary adenoma. The consequent hypercortisolaemia gives rise to characteristic features of the disease and its morbidities. Treatments aim to restore normal cortisol levels, provide long-term control of the disease and the tumour, and the improvement of patient well-being. The first line of treatment remains transsphenoidal surgery with remission rates of 65-90% in CD secondary to a pituitary microadenoma. Second-line treatment includes repeat surgery, radiotherapy, medical therapy, and bilateral adrenalectomy. The success rate of radiotherapy ranges from 46% to 74% and is probably independent of the mode of delivery of the radiation, but may take several years to become effective. Medical therapy is useful in acutely unwell patients or while awaiting radiotherapy to become effective. The most often-used medical agents include metyrapone and ketoconazole, which inhibit steroidogenesis; less often, centrally-acting drugs or a glucocorticoid receptor blocker are used, but experience with them is more limited. Bilateral adrenalectomy remains an important treatment option to control unresponsive severe hypercortisolism, particularly in patients with severe CD.The management of childhood CD does not differ from adult disease, with transsphenoidal surgery as successful as in adults but radiotherapy is more rapid in onset. Regardless of the age of the patient, Cushing's disease remains a challenge to the physician and requires a multidisciplinary approach to achieve the most desirable outcome.

Medullary thyroid carcinoma and duodenal calcitonin-secreting neuroendocrine tumour: more than coincidence?

Neuroendocrine tumours (NETs) are a heterogeneous group of neoplasms whose management can be problematic. In many cases, multiple tumours may occur in the same patient or his or her family, and some of these have now been defined genetically, although in other cases the underlying gene or genes involved remain unclear. We describe a patient, a 63-year-old female, who was diagnosed with a medullary thyroid carcinoma (MTC), which was confirmed pathologically after thyroidectomy, but whose circulating calcitonin levels remained elevated after thyroidectomy with no evidence of metastatic disease. Subsequently, an entirely separate and discrete duodenal NET was identified; this was 2.8 cm in diameter and was removed at partial duodenectomy. The tumour stained immunohistochemically for calcitonin, and its removal led to persistent normalisation of the circulating calcitonin levels. There was no germline mutation of the RET oncogene. This is the first identification of a duodenal NET secreting calcitonin and also the first demonstration of a second tumour secreting calcitonin in a patient with MTC. We suggest that where calcitonin levels remain high after removal of a MTC a search for other NETs should be conducted.

Phase-I human clinical-trial of onconase(r) (p-30 protein) administered intravenously on a weekly schedule in cancer-patients with solid tumors

ONCONASE(R) (ONC), previously known as P-30 Protein, is a novel amphibian protein isolated from Rana pipiens eggs/early embryos (1) which demonstrates cytostatic and cytotoxic activity against several human tumor cell lines in vitro, as well as anti-tumor activity in vivo. Animal toxicology studies in rats and dogs revealed dose-dependent weight loss, some skeletal muscle and myocardial degenerative changes, a decrease in albumin and bilirubin levels in rats, and a dose-related elevation of serum transaminases and alkaline phosphatase in both species. A human weekly schedule Phase I study of intravenous bolus ONC was initiated, with dose levels ranging from 60 mug/m2 (anticipated human dose) to 960 mug/m2. Five patients were treated per dose level, without dose escalations within the same patients. Dose levels were doubled in new groups of patients with a variety of relapsing and resistant tumors. A correlation was noted between the dose level and the number of doses (cumulative effect), and the toxicities observed. The dose limiting toxicity was renal as manifested by proteinuria with edema, +/- azotemia and fatigue. Other side effects included flushing, myalgias, transient dizziness, and decreased appetite. Two patients, one at 480 mug/m2 and another at 960 mug/m2 levels, developed reversible hypotensive reactions preceded by flushing. The maximum tolerated dose (MTD) appears to be 960 mug/m2. Incidental findings included some objective responses in non-small cell lung, esophageal, and colorectal carcinomas. It has been concluded that ONCONASE was well tolerated by the majority of patients, demonstrated a consistent and reversible clinical toxicity patterns, did not induce most of the toxicities (such as, e.g., myelosuppression and alopecia) associated with most of the chemotherapeutic agents and, in view of its demonstrated objective clinical activity observed in patients harboring resistant solid tumors, the Phase II clinical trials have been initiated and are currently ongoing.

Isolation and characterization of a gene for a major light-harvesting polypeptide from Cyanophora paradoxa

Antibodies raised against mixtures of phycobilisome polypeptides from the eukaryotic alga Cyanidium caldarium were used in an immunological screen to detect expression of phycobiliprotein genes in an Escherichia coli library containing segments of plastid (chloroplast, cyanelle) DNA from another eukaryotic alga, Cyanophora paradoxa. The four candidate clones obtained were mapped by restriction analysis and found to be overlapping. The clone with the smallest insert (1.4 kilobases) was partially sequenced and a coding region similar to the carboxyl terminus of the phycobiliprotein subunit beta-phycocyanin was found. The coding region for the beta-phycocyanin gene in C. paradoxa has been mapped to the small single copy region on the cyanelle genome, and its orientation has been determined. A short probe unique to a conserved chromophore binding site shared by at least two phycobiliprotein subunits has now been generated from the carboxyl terminus of the beta-phycocyanin gene. This probe may be useful in identifying specific phycobiliprotein subunit genes, beta-phycocyanin, beta-phycoerythrocyanin, and possibly beta-phycoerythrin, in other eukaryotic algae and in prokaryotic cyanobacteria.

Cytoplasmic and chloroplast synthesis of phycobilisome polypeptides

In vivo labeling of eukaryotic phycobilisomes in the presence of inhibitors of translation on 70S and 80S ribosomes demonstrates that some of the polypeptides of this light-harvesting complex are synthesized in the cytoplasm while others are synthesized in the chloroplast. The major pigmented polypeptides, the alpha and beta subunits of the biliproteins (molecular weights between 15,000 and 20,000) and the anchor protein (molecular weight about 90,000) are translated on 70S ribosomes. This suggests that these polypeptides are made within the algal chloroplast. Because the alpha and beta subunits comprise a group of closely related polypeptides, the genes encoding these polypeptides may reside in the plastid genome as a multigene family. Other prominent phycobilisome polypeptides, including a nonpigmented polypeptide that may be involved in maintaining the structural integrity of the complex, are synthesized on cytoplasmic ribosomes. Because the synthesis of phycobilisomes appears to require the expression of genes in two subcellular compartments, this system may be an excellent model for: (i) examining interaction between nuclear and plastid genomes: (ii) elucidating the molecular processes involved in the evolution of plastid genes: (iii) clarifying the events in the synthesis and assembly of macromolecular complexes in the chloroplast.

Guidelines for the treatment of growth hormone excess and growth hormone deficiency in adults

The V Consensus Group Meeting on 'Guidelines for Treatment of GH Excess and GH Deficiency in the Adult' was an international workshop held on February 20-22, 2006 in Santa Monica, California, USA. The principal aim of this meeting was to provide guidelines for the evaluation and treatment of adults with either form of abnormal GH secretion: GH excess or GH deficiency. The workshop included debates as to the choice of primary treatment, discussions of the targets for adequate treatment, and concluded with presentations on open issues germane to adult GH treatment including the role of GH in malignancies, the impact of longterm treatment on bone, and a cost-benefit analysis. The meeting was comprised of 66 delegates representing 13 different countries.

Severe digital ischemia–a presenting symptom of malignancy–associated antiphospholipid syndrome

The association of the antiphospholipid syndrome with malignancy has been extensively reported. Raynaud’s phenomenon has also been reported to be associated with various malignancies. In this report, we describe two patients who presented with severe digital ischemia mimicking Raynaud’s phenomenon. The patients were found to have antiphospholipid syndrome, and upon extensive evaluation, a diagnosis of a malignancy was made. This report highlights the importance of malignancy workup in patients with severe digital ischemia associated with antiphospholipid syndrome.

The regulation of hypothalamic corticotropin-releasing factor release: in vitro studies

Although there are various ways in which the regulation of hypothalamic corticotropin-releasing factor (CRF) may be investigated, the most direct is by the study of CRF secretion from rat hypothalami incubated in vitro. Using this technique, we have found stimulation of secretion by noradrenaline, acetylcholine, serotonin, neuropeptide Y, and interleukins 1 and 6; inhibitory modulation was shown by GABA, substance P, atrial natriuretic peptide, opioid peptides and precursors of nitric oxide. Studies of these interactions demonstrated certain non-linear characteristics which may allow appropriate mathematical models to be devised; this may aid in our understanding of clinical disorders associated with CRF excess.

Genomics, environmental genomics and the issue of microbial species

A microbial species concept is crucial for interpreting the variation detected by genomics and environmental genomics among cultivated microorganisms and within natural microbial populations. Comparative genomic analyses of prokaryotic species as they are presently described and named have led to the provocative idea that prokaryotes may not form species as we think about them for plants and animals. There are good reasons to doubt whether presently recognized prokaryotic species are truly species. To achieve a better understanding of microbial species, we believe it is necessary to (i) re-evaluate traditional approaches in light of evolutionary and ecological theory, (ii) consider that different microbial species may have evolved in different ways and (iii) integrate genomic, metagenomic and genome-wide expression approaches with ecological and evolutionary theory. Here, we outline how we are using genomic methods to (i) identify ecologically distinct populations (ecotypes) predicted by theory to be species-like fundamental units of microbial communities, and (ii) test their species-like character through in situ distribution and gene expression studies. By comparing metagenomic sequences obtained from well-studied hot spring cyanobacterial mats with genomic sequences of two cultivated cyanobacterial ecotypes, closely related to predominant native populations, we can conduct in situ population genetics studies that identify putative ecotypes and functional genes that determine the ecotypes' ecological distinctness. If individuals within microbial communities are found to be grouped into ecologically distinct, species-like populations, knowing about such populations should guide us to a better understanding of how genomic variation is linked to community function.

Peripheral blood mononuclear and tumor cell pharmacodynamics of the novel epothilone B analogue, ixabepilone

BACKGROUND

We previously demonstrated that peak microtubule bundle formation (MBF) in peripheral blood mononuclear cells (PBMCs) occurs at the end of drug infusion and correlates with drug pharmacokinetics (PK). In the current study, a new expanded evaluation of drug target effect was undertaken.

PATIENTS AND METHODS

Patients with advanced solid malignancies were treated with ixabepilone 40 mg/m2 administered as a 1-h i.v. infusion every 3 weeks. Blood, plasma, and tumor tissue sampling was carried out to characterize pharmacodynamics and PK.

RESULTS

Forty-seven patients were treated with 141 cycles of ixabepilone. In both PBMCs (n=27) and tumor cells (n=9), peak MBF occurred at the end of infusion; however, at 24-72 h after drug infusion, the number of cells with MBF was significantly greater in tumor cells, relative to PBMCs. A Hill model (EC50=109.65 ng/ml; r2=0.94) was fitted, which demonstrated a relationship between percentage of PBMCs with MBF and plasma ixabepilone concentration. The percentage of PBMCs with MBF at the end of infusion also correlated with severity of neutropenia (P=0.050).

CONCLUSIONS

Plasma ixabepilone concentration and severity of neutropenia correlate with the level of MBF in PBMCs. Therefore, this technically straightforward assay should be considered as a complement to the clinical development of novel microtubule-binding agents.

Parachute approach to evidence based medicine

Waiting for the results of randomised trials of public health interventions can cost hundreds of lives, especially in poor countries with great need and potential to benefit. If the science is good, we should act before the trials are done

Mitochondrial metabolism reveals a functional architecture in intact islets of Langerhans from normal and diabetic Psammomys obesus

The cells within the intact islet of Langerhans function as a metabolic syncytium, secreting insulin in a coordinated and oscillatory manner in response to external fuel. With increased glucose, the oscillatory amplitude is enhanced, leading to the hypothesis that cells within the islet are secreting with greater synchronization. Consequently, non-insulin-dependent diabetes mellitus (NIDDM; type 2 diabetes)-induced irregularities in insulin secretion oscillations may be attributed to decreased intercellular coordination. The purpose of the present study was to determine whether the degree of metabolic coordination within the intact islet was enhanced by increased glucose and compromised by NIDDM. Experiments were performed with isolated islets from normal and diabetic Psammomys obesus. Using confocal microscopy and the mitochondrial potentiometric dye rhodamine 123, we measured mitochondrial membrane potential oscillations in individual cells within intact islets. When mitochondrial membrane potential was averaged from all the cells in a single islet, the resultant waveform demonstrated clear sinusoidal oscillations. Cells within islets were heterogeneous in terms of cellular synchronicity (similarity in phase and period), sinusoidal regularity, and frequency of oscillation. Cells within normal islets oscillated with greater synchronicity compared with cells within diabetic islets. The range of oscillatory frequencies was unchanged by glucose or diabetes. Cells within diabetic (but not normal) islets increased oscillatory regularity in response to glucose. These data support the hypothesis that glucose enhances metabolic coupling in normal islets and that the dampening of oscillatory insulin secretion in NIDDM may result from disrupted metabolic coupling.

Diagnostic performance of CT versus MR in detecting aldosterone-producing adenoma in primary hyperaldosteronism (Conn's syndrome)

The aim of the present study is to compare the diagnostic performance of CT and MR imaging in detecting aldosterone-producing adenoma and to compare the interobserver variability in the detection of an aldosterone-producing adenoma on CT and MR. A retrospective study of 34 patients with primary hyperaldosteronism was performed. A total of 17 cases of aldosterone-producing adenoma and 17 cases of bilateral adrenal hyperplasia were included. The final diagnosis of an adenoma was made by surgery with histological confirmation, whereas that of bilateral adrenal hyperplasia was made on adrenal venous sampling or a good biochemical and clinical response following medical treatment alone and in the absence of a unilateral radiological abnormality. The CT (n=30) and MR (n=24) scans were reviewed independently by two radiologists experienced in adrenal imaging, who were unaware of the cause of the primary hyperaldosteronism. The diagnostic performances of both observers in detecting an aldosterone-producing adenoma on CT and MR imaging were compared. The 16 adenomatous nodules that were detected on imaging ranged from 1 to 4.75 cm in diameter. The calculated sensitivity and specificity for detecting aldosterone-producing adenoma were 87 and 93% for one observer and 85 and 82% for the other observer on CT, and 83 and 83% for one observer and 92 and 92% for the other observer on MR, respectively. Receptor operating characteristics curve analysis showed similar performances of both observers in detecting an aldosterone-producing adenoma on CT and MR imaging. There was good interobserver agreement on CT (k=0.71) and on MR (k=0.67). We have demonstrated comparable diagnostic performance and good interobserver agreement on CT and MR imaging for the detection of aldosterone-producing adenoma.

CT of primary hyperaldosteronism (Conn's syndrome): the value of measuring the adrenal gland

OBJECTIVE

The objectives of our study of patients with primary hyperaldosteronism (Conn's syndrome) were to determine whether the adrenal glands are larger in patients with bilateral adrenal hyperplasia than in those with aldosterone-producing adenomas or in healthy control subjects; and whether a CT criterion based on adrenal gland size can be developed to positively diagnose bilateral adrenal hyperplasia.

MATERIALS AND METHODS

A retrospective study of CT scans of 28 patients with primary hyperaldosteronism was performed. The means of two observers' measurements of adrenal gland size were recorded and compared with published normal values. In addition, a radiologist experienced in adrenal imaging and unaware of the cause of the primary hyperaldosteronism diagnosed either bilateral adrenal hyperplasia or aldosterone-producing adenoma by visual inspection.

RESULTS

The adrenal glands in patients with bilateral adrenal hyperplasia were significantly (p < 0.05) larger than those in patients with aldosterone-producing adenoma or in healthy control subjects. A sensitivity of 100% was achieved when a mean limb width of greater than 3 mm was used to diagnose bilateral adrenal hyperplasia, and a specificity of 100% was achieved when the mean limb width was 5 mm or greater. Receiver operating characteristic curve analysis showed that the overall performance of the radiologist and the mean adrenal limb width in detecting bilateral adrenal hyperplasia were equivalent.

CONCLUSION

In patients with primary hyperaldosteronism, adrenal limb measurements on CT can aid in differentiating bilateral adrenal hyperplasia from aldosterone-producing adenoma because the adrenal glands in bilateral adrenal hyperplasia are larger.

Biochemical and imaging evaluation of Cushing's syndrome

The diagnosis and differential diagnosis of Cushing's syndrome remains a considerable challenge in clinical endocrinology. Investigation is a two-step process, involving first diagnosis followed by differential diagnosis. Traditionally diagnosis has relied upon urinary free cortisol (UFC) collection, low-dose dexamethasone-testing, and assessment of midnight cortisol. More recently, differentiation between mild disease and pseudo-Cushing's states has been achieved using dexamethasone-suppressed corticotropin releasing hormone (CRH) and desmopressin tests. Refinements of tests used for differential diagnosis have been made including optimized response criteria for ovine and human sequence CRH tests, desmopressin tests, GHBP-testing and testing with combinations of peptides. Despite improvements in these non-invasive tests use of inferior petrosal or cavernous sinus sampling is frequently required. Imaging is guided by biochemical assessment. MRI is the investigation of choice for Cushing's disease, but is often negative. Scintigraphic investigation using radionucleotide-labeled agonists for receptors commonly expressed by neuroendocrine tumors the investigation of occult ACTH-dependent disease remains disappointing. In this review we critically analyze the tests used for this most challenging of clinical conditions.

Movement-related potentials during the performance of a motor task I: the effect of learning and force

Movement-related potentials (MRPs) recorded from the brain may be affected by several factors. These include the how well the subject knows the task and the load against which he performs it. The objective of this study is to determine how dominant these two factors are in influencing the shape and power of MRPs. MRPs were recorded during performance of a simple motor task that required learning of a force. A stochastic algorithm was used in order to partition a set of MRPs that are embedded in the surrounding electroencephalographic (EEG) activity into distinct classes according to the power of the underlying MRPs. Our results show that the most influential factor in the partition was the load against which the subject performed the task. Furthermore, it was found that learning has a smaller, though not insignificant, influence on the power of the MRPs.

Movement-related potentials during the performance of a motor task II: cerebral areas activated during learning of the task

Movement-related potentials (MRPs) recorded from the brain are thought to vary during learning of a motor task. However, since MRPs are recorded at a very low signal-to-noise ratio, it is difficult to measure these variations. In this study we attempt to remove most of the accompanying noise thus enabling the tracking of transient phenomena in MRPs recorded during learning of a motor task. Subjects performed a simple motor task which required learning. A modified version of the matching pursuit algorithm was used in order to remove a significant portion of the electroencephalographic noise overlapping the MRPs recorded in the experiment. Small groups of MRPs were then averaged according to experimental parameters. Our results show that the power of the MRPs does not decay uniformly during learning. Instead, there is a significant peak in their power after 4 or 5 repetitions of the task. This peak is noticeable especially in electrodes placed over the prefrontal region of the cortex at times subsequent to the actual movement. The observed pattern of activity may indicate problem solving related to comprehension of the force against which the user performed the task. It is possible that this problem solving occurs in the prefrontal cortex.

TACI-Ig neutralizes molecules critical for B cell development and autoimmune disease. impaired B cell maturation in mice lacking BLyS

BLyS and APRIL have similar but distinct biological roles, mediated through two known TNF receptor family members, TACI and BCMA. We show that mice treated with TACI-Ig and TACI-Ig transgenic mice have fewer transitional T2 and mature B cells and reduced levels of circulating immunoglobulin. TACI-Ig treatment inhibits both the production of collagen-specific Abs and the progression of disease in a mouse model of rheumatoid arthritis. In BLyS-deficient mice, B cell development is blocked at the transitional T1 stage such that virtually no mature B cells are present, while B-1 cell numbers are relatively normal. These findings further elucidate the roles of BLyS and APRIL in modulating B cell development and suggest that BLyS is required for the development of most but not all mature B cell populations found in the periphery.

Gaseous neuromodulators in the control of neuroendocrine stress axis

The gaseous neuromodulator carbon monoxide has been shown to reduce the stimulated release of stress neuropeptides, such as vasopressin and oxytocin, from the rat hypothalamus in vitro, while evidence concerning corticotropin-releasing hormone is controversial. In vivo studies have been conducted in the rat, inhibiting heme oxygenase activity--and hence carbon monoxide biosynthesis--in the central nervous system by means of specific heme oxygenase blockers; these studies showed that basal heme oxygenase activity tends to oppose exaggerated increases in vasopressin secretion following immune-inflammatory challenges, whereas it favors the normal rise in circulating ACTH which follows footshock. Another gas normally produced in mammalian brains under basal conditions, hydrogen sulfide, also appears to play a role in the control of the hypothalamo-pituitary-adrenal axis. Indeed, increases in hydrogen sulfide levels within the hypothalamus, either obtained with hydrogen sulfide-enriched media or by the addition of the hydrogen sulfide precursor S-adenosyl-methionine, are associated with the inhibition of the stimulated release of corticotropin-releasing hormone from rat hypothalamic explants. Parellel in vivo experiments in the rat under resting conditions and after stress-induced adrenocortical activation show that S-adenosyl-methionine significantly reduces the rise in serum corticosterone levels caused by 1-h exposure to cold. These results demonstrate the pathophysiological importance of both carbon monoxide and hydrogen sulfide in the regulation of neuroendocrine function.

Breathing-control lowers blood pressure

We hypothesise that routinely applied short sessions of slow and regular breathing can lower blood pressure (BP). Using a new technology BIM (Breathe with Interactive Music), hypertensive patients were guided towards slow and regular breathing. The present study evaluates the efficacy of the BIM in lowering BP. We studied 33 patients (23M/10F), aged 25-75 years, with uncontrolled BP. Patients were randomised into either active treatment with the BIM (n = 18) or a control treatment with a Walkman (n = 15). Treatment at home included either musically-guided breathing exercises with the BIM or listening to quiet music played by a Walkman for 10 min daily for 8 weeks. BP and heart rate were measured both at the clinic and at home with an Omron IC BP monitor. Clinic BP levels were measured at baseline, and after 4 and 8 weeks of treatment. Home BP measurements were taken daily, morning and evening, throughout the study. The two groups were matched by initial BP, age, gender, body mass index and medication status. The BP change at the clinic was -7.5/-4.0 mm Hg in the active treatment group, vs -2.9/-1.5 mm Hg in the control group (P = 0.001 for systolic BP). Analysis of home-measured data showed an average BP change of -5.0/-2.7 mm Hg in the active treatment group and -1.2/+0.9 mm Hg in the control group. Ten out of 18 (56%) were defined as responders in the active treatment group but only two out of 14 (14%) in the control group (P = 0.02). Thus, breathing exercise guided by the BIM device for 10 min daily is an effective non-pharmacological modality to reduce BP.

The roles of carbon monoxide and nitric oxide in the control of the neuroendocrine stress response: complementary or redundant

There is widespread evidence in favour of nitric oxide (NO) acting as a gaseous neurotransmitter in the central nervous system, diffusing from its cells of origin and affecting surrounding neuronal tissue in evanescent three-dimensional waves. This is also true of the hypothalamus, where amongst other activities NO inhibits stimulation of corticotrophin-releasing hormone (CRH) and vasopressin release by inflammatory stressors, effects thought to be mediated by binding with soluble guanylate cyclase (sGC). Carbon monoxide is being increasingly recognised as another gaseous neuromodulator, but with principal effects on other hemoproteins such as cyclo-oxygenase, and a distinctly different profile of localisation.NO is predominantly a pro-inflammatory agent in the periphery while CO is often anti-inflammatory. In the hypothalamus, the actions of CO are also distinct from those of NO,with marked antagonistic effects on the inflammatory release of vasopressin, both in vitro and in vivo, but with little involvement in the regulation of CRH. Thus, it would appear that these apparently similar gases exert quite distinct and separate effects, although they cause broadly similar overall changes in the secretion of neuroendocrine stress hormones. We conclude that these two gases may play significant but different roles in the control of the neuroendocrine stress response, but one common feature may be attenuation of inflammation-induced release of stress hormones.