Surviving a stroke in South Africa: outcomes of home-based care in a low-resource rural setting

Background: Little is known of stroke outcomes in low- and middle-income countries with limited formal stroke rehabilitation services and of homebased-stroke services delivered within the primary health care (PHC) context by community health workers (CHWs).

Objectives: To describe and analyze the outcomes of patients with stroke from a rural PHC setting in the Western Cape, South Africa.

Methods: In a longitudinal survey, 93 stroke patients, referred to home and community-based care services (HCBC) between June 2015 and December 2017, were assessed at baseline, one month and three months. Changes in function (Barthel Index (BI)), caregiver strain (Caregiver Strain Index (CSI)), impact of environmental factors and satisfaction with stroke care were measured.

Results: HCBC was delayed, fragmented and brief (median session duration 20 minutes (IQR 15.0–30.0)). Although function improved significantly, dependence remained high: median BI score changed from 40.0 (IQR 15.0–70.0) to 62.5 (IQR 30.0–81.25) (p = .019). A third (33.0% (30/91)) of caregivers initially experienced strain and the median CSI score remained 3.0 (IQR 0.0–7.0) (p = .672). Overall, patient and caregiver satisfaction with HCBC was low with only 46.9% (31/66) of caregivers and 17.4% (12/69) of patients satisfied with all aspects of care. Only 47.6% of assistive product needs were met. Environmental factors negatively impacted on patient function and caregiving.

Conclusions: Clinical practice pathways and referral guidelines should be developed for the HCBC platform. Specific training of CHWs, focusing on how to educate, support and train family caregivers, provide assistive devices and refer to health services is needed.     

On the origin of apparent low tissue signals in balanced SSFP.

Balanced steady-state free precession (bSSFP) has become increasingly important in clinical applications. Its signal properties have been investigated over several years by many groups, and various critical factors for bSSFP signal intensity and stability, such as off-resonances, flow, and eddy currents, have been identified. It is generally accepted that bSSFP signal intensity is a function of relaxation times, excitation angles, and spin densities only. While this is true for simple phantoms, it appears that signals from tissues are significantly less intense than predicted by theory. This work demonstrates that the molecular origin of this apparent signal reduction is due to on-resonance magnetization transfer (MT). High flip angles in combination with very short repetition times (TRs), as commonly used for bSSFP, lead to a considerable saturation in the fraction of macromolecular (MM) pool protons. As a result, bSSFP signal is strongly attenuated by up to a factor of 2 in the human brain compared to the signal expected from theory.     

Alternating repetition time balanced steady state free precession.

A novel balanced SSFP technique for the separation or suppression of different resonance frequencies (e.g., fat suppression) is presented. The method is based on applying two alternating and different repetition times, TR(1) and TR(2). This RF scheme manipulates the sensitivity of balanced SSFP to off-resonance effects by a modification of the frequency response profile. Starting from a general approach, an optimally broadened stopband within the frequency response function is designed. This is achieved with a TR(2) being one third of TR(1) and an RF-pulse phase increment of 90 degrees . With this approach TR(2) is too short ( approximately 1 ms) to switch imaging gradients and is only used to change the frequency sensitivity. Without a significant change of the spectral position of the stopband, TR(1) can be varied over a range of values ( approximately 2.5-4.5 ms) while TR(2) and phase cycling is kept constant. On-resonance spins show a magnetization behavior similar to balanced SSFP, but with maximal magnetization at flip angles about 10 degrees lower than in balanced SSFP. The total scan time is increased by about 30% compared to conventional balanced SSFP. The new technique was applied on phantoms and volunteers to produce rapid, fat suppressed images.     

The gene for the iron sulfur protein of succinate dehydrogenase (SDH-IP) maps to human chromosome 1p35-36.1

A partial human cDNA clone for the iron-protein (IP) subunit of succinate dehydrogenase (EC 1.3.99.1) was used in Southern analyses of restriction enzyme digests of genomic human and hamster DNA as well as hamster-human hybrids containing a limited number of human chromosomes. The gene for this protein was mapped to human chromosome 1. Digestion of genomic DNA with several restriction enzymes yielded two fragments detectable on a Southern blot, in contrast to the expectations based on the sequence of the cDNA clone. A preliminary analysis of a genomic clone with most of theIP gene has indicated the presence of several introns containing restriction sites detected by the Southern analysis. This genomic clone was also used for subregional mapping by fluorescence in situ hybridization (FISH) to human metaphase chromosomes. A single locus in the region 1p35-36.1 was identified.     

Conventional MRA and contrast- enhanced MRA of extracranial vessel segments

Summary The introduction of fast gradient systems allows a reliable visualization of the extracranial carotid vessels by the magnetic resonance angiography (MRA) which meanwhile is implemented into clinical routine. By the mainly applied time-of-flight (TOF) technique, vessels can be imaged without contrast agent (CA). Due to the application of ultra-fast gradient-echo-sequences, the first-pass evaluation of an intravenous bolus-injection of Gadolinium in the carotids from the aortic arch up to the skull base can be performed in less than 30 s. In this study, advantages and disadvantages of both techniques are discussed. For a qualitatively optimal contrast enhanced MRA (CE-MRA) timing parameters like injection delay, flow rate and the adjustment of sequence parameters have to be considered in relation to the fast venous return from the sinus to the jugular veins. First, the optimal time point of the data acquisition have been determined at a model and with a computer simulation in reference to the presence of CA in the arteries. As a result, 90 % of the contrast contribution is defined by 16 % of the symmetrically acquired central k-space lines. A measuring protocol for clinical use was obtained by a gradual variation of spacial resolution, measuring time and CA-injection parameters and was proved in normal volunteers and patients. An exact determination of the bolus-arrival-time by means of a test-bolus injection was acquired. The best qualitative results were achieved by a double-dose injection at 2 ml/s injection rate. The temporal reserves of ultra-fast sequences should be invested in the improvement of the spatial resolution. To date, further investigations related to the problem of optimal CA-application may improve the potentials of CE-MRA procedures.      

Revisionsersatz des vorderen Kreuzbandes

With increasing numbers of primary anterior cruciate ligament reconstruction, the incidence of unsatisfactory results and graft failures will increase. The goals of revision reconstruction are similar to those of primary reconstruction and include stabilization of the knee, prevention of secondary degenerative changes, and recovery of knee function. Besides the recurrent tear there are specific technical failures, such as tunnel malplacement and unrecognized associated ligamentous pathologies, which might lead to graft failure. Thus, preoperative planning includes a detailed analysis of failure mechanisms by thorough preoperative history taking, comprehensive physical examination, and appropriate radiographic evaluation. The treatment algorithm addresses issues of hardware removal, need for a staged procedure or concomitant surgery, graft source, tunnel placement, and graft fixation. Correct placement of tunnels and graft fixation are the essential surgical steps, which might also influence graft selection. Successful revision ACL surgery requires a motivated and compliant patient and an experienced surgeon who is proficient in a variety of different surgical techniques. However, since clinical outcome is reported to be inferior in revision compared to primary ACL reconstruction the importance of counseling the patient preoperatively regarding less satisfactory results than in most primary ACL reconstructions must be emphasized. This article describes indications, analysis and surgical procedures for revision anterior cruciate ligament reconstruction.     

Chinese hamster cells deficient in ornithine decarboxylase activity: Reversion by gene amplification and by azacytidine treatment

A group of Chinese hamster ovary (CHO) cell mutants deficient in ornithine decarboxylase (ODC) activity are described and compared to the prototype mutant reported previously (21). Although all mutants belong to the same complementation group, they can be divided into two classes: those with some residual enzyme activity and those with no activity. All mutants are putrescine auxotrophs, but they differ in their ability to utilize the enzyme's substrate, ornithine, a property which correlates with the amount of residual enzyme activity. The mutants also differ in their frequency of reversion to prototrophy. The leaky mutants revert at a high rate by overproducing a partially defective enzyme by a gene amplification mechanism similar to that leading to the ornithine analog-resistant mutants which have elevated enzyme levels. Spontaneous reversion in the null mutants is rare. However, one null mutant, which was induced with ethyl methane sulfonate and which makes ODC mRNA but no active enzyme, is nevertheless revertible with 5-azacytidine. We conclude that CHO cells are at least diploid at the ODC locus, but that only one allele is active. Further studies suggest the possibility that ethyl methane sulfonate is not just a classical mutagen but may also induce gene inactivations that are revertible by 5-azacytidine.     

Managed behavioral health care and supply-side economics. 1998 Carl Taube Lecture

BACKGROUND: Within the past decade, the mental health care system in the United States has undergone a significant transformation in terms of delivery, financing and work force configuration. Contracting between managed care organizations (MCOs) and providers has become increasingly prevalent, paralleling the trend in health care in general. These managed care carve-outs in behavioral health depend on networks of providers who agree to capitated rates or discounted fees for service for those patients covered by the carve-out contracts. Moreover, the carve-outs use a broader array of mental health providers than is typically found in traditional indemnity plans, encourage time-limited versus long-term treatments and favor providers who are engaged in outpatient care. This phenomenal growth in managed behavioral health care over the past decade includes the rapid growth and quick consolidation of mental health MCOs. The period 1992-1998 shows steady and substantial annual increases in the number of enrollees in mental health MCOs, the figure more than doubling from 78.1 million people in 1992 to a projected 156.6 million in 1998, or 70% of insured lives. Moreover, these vast numbers of enrollees are becoming increasingly consolidated into a smaller number of firms. In 1997, 12 companies controlled nearly 85% of the managed behavioral health care market, with 60% of the market held by the three largest firms. STUDY AIMS: This article reviews empirical data and draws policy implications from the literature on managed behavioral health care in the United States. Starting with spending and spending trend estimates that show the average annual growth rate of mental health expenditures to be lower than that of health care expenditures in general over the past decade, the author examines utilization and price factors that may account for managed-care-induced cost reductions in behavioral health care, with special attention to hospital use patterns, fee discounting and the supply and earnings patterns of various types of mental health provider. In addition, data on staffing ratios and provider mixes of health maintenance organizations and mental health MCOs are reviewed as they reveal at least part of the dynamics of reconfiguration of the mental health work force in this era of managed care. CONCLUSIONS: As measured by changes in utilization and price, widespread application of "classic" managed care techniques such as preadmission review (gatekeeping), concurrent review, case management, standardized clinical guidelines and protocols, volume purchase of services and fee discounting appears to have led to significant cost reductions for providers of both impatient and outpatient mental health services. However, amidst a complex flux of market variables such as risk shifting, changing financial incentives and intensity of competition, not all of the reduction or slowdown in spending can be clearly and purely attributed to managed care. The data on the ongoing reconfiguration of the mental health work force are clearer in their implications: with an oversupply of all types of mental health providers, managed care has significant potential to increase the incidence of provider substitutions and spur the growth of integrated group practices. IMPLICATIONS FOR FURTHER RESEARCH: The current body of empirical and policy literature in mental health economics suggests several salient areas of follow-up. Is the proportionately greater impact of managed care on the annual growth rate of mental health care spending a temporary phenomenon or does it signal an enduring difference in the rates of increase between behavioral health care and health care in general? Beyond industry downsizing, what are the substitutions among mental health providers that are going on, and will go on, to produce cost-effective practices? What are the new financial or risk-sharing arrangements between providers and MCOs that will produce appropriate and high-quality mental health services?     

Dynamic susceptibility contrast MR imaging of plaque development in multiple sclerosis: application of an extended blood-brain barrier leakage correction

Since the pathogenesis of multiple sclerosis (MS) lesions is not yet fully understood, we investigated the potential of dynamic susceptibility contrast (DSC) magnetic resonance (MR) perfusion imaging for a better characterization of lesion pathology. Twenty-five MS patients were examined on a 1.5 T scanner. A single dose of gadolinium (Gd)-DOTA contrast agent was injected, and echoplanar images were acquired every 0.5 seconds for 1 minute. From the signal intensity-versus-time curves, the relative cerebral blood volume (rCBV) was evaluated for regions in plaques and in gray and white matter. The rCBV calculated for acute, Gd-enhancing plaques was corrected for the effects of blood-brain barrier leakage, using a new correction algorithm. Acute plaques had significantly higher blood volumes than normal-appearing white matter (P < = 0.01). Chronic plaques that appeared hypointense on T(1)-weighted images had lower rCBV than T(1)-isointense plaques (P < = 0.03). Our results indicate that the acute phase in MS is accompanied by vasodilation. In later stages of gliosis, the perfusion decreases with increasing axonal injury. Although the DSC technique is less sensitive than conventional MR imaging, the information provided is essentially different from that obtained with any other MR method.