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Biomedical subjects

S Jackson

Publications and source records attributed to S Jackson.

At least 145 records · Page 8Linked to original sources
PubMed1998

Eradication of schistosomiasis in Guangxi, China. Part 1: Setting, strategies, operations, and outcomes, 1953-92.

Reported are the results of an analysis of a 40-year programme leading to eradication of schistosomiasis in Guangxi, China, a large, poor autonomous region of the country that had the heaviest global burden of the disease. We used historical county data and maps showing the initial distribution and density of Oncomelania snails and the initial prevalence of schistosomiasis to assess the correlation between snail occurrence and human infection. All annual county schistosomiasis reports were collected and analysed, including information on snail abundance and infection, human and animal infection control, stool examinations and patient treatments, clinical and serology examinations, skin test surveillance, patient follow-up, patient treatments, animal examinations, water supply and sanitation, and environmental modification. The findings bear witness to the laborious, systematic and scientific basis of the control programme and how it changed over the 40 years. Of note is the continual search for and treatment of cases, the killing of snails, and the permanent alteration of their habitats using mass community participation and methods adapted to local conditions. The programme has freed more than 10 million people from the risk of schistosomiasis and boosted rural economic development and health. The persistence, good record keeping, evolving and locally flexible strategies, and the clear focus of the control programme were crucial to its eventual success.

Animals↗
PubMed1998

Perinatal expression of genes that may participate in lipid metabolism by lipid-laden lung fibroblasts.

Although a morphologically distinct population of lipid-laden interstitial cells (lipofibroblasts, LF), has been identified, the origins and functions of this population during lung development and disease remain undefined. Illumination of the developmental and functional characteristics of two other populations of lipid-laden mesenchymal cells, namely adipocytes and hepatic lipocytes, has fashioned tools that can be used to explore similar properties in pulmonary LFs. As the LF is transiently a very abundant cell in the perinatal lung, we elected to study the perinatal ontogeny of the expression of several genes that are involved in the acquisition of lipids by adipocytes, and may be involved in promoting the triglyceride accumulation that is the morphologic hallmark of the pulmonary LF. We found that the maximal expression of peroxisome proliferator-activated receptor-gamma (PPAR-gamma), at gestational day 21 in the LF, precedes the rise at birth, in the expression of genes that are involved in the hydrolysis of triglycerides at the plasma membrane (lipoprotein lipase, LPL), transport of fatty acids across the plasma membrane (fatty acid transporter, FAT) and in the cytoplasm (adipocyte lipid binding protein, ALBP). The steady-state levels of LPL, FAT, and ALBP mRNAs that were isolated from whole lung tissue showed a similar temporal pattern. The levels of the protein products of the LPL and ALBP genes changed in tandem with those of their precursor mRNAs in the LF, suggesting that these gene products are under pre-translational control. These findings indicate that characteristic adipocyte genes are also expressed in lipid-laden pulmonary fibroblasts and may participate in triglyceride accumulation and metabolism by these cells.

Animals↗
PubMed1998

Eradication of schistosomiasis in Guangxi, China. Part 2: Political economy, management strategy and costs, 1953-92.

Reported are the results of a study of the political economy, management, and costs of the successful Guangxi schistosomiasis eradication programme, spanning 40 years from 1953 to 1992. For this purpose we analysed all government data and memoranda on the policy, management, technical support, finance, and the control strategy of the programme. We also interviewed many local staff involved in the programme over the 40-year period and obtained cost data from annual county-level records on seven major categories of variable costs. Schistosomiasis control in Guangxi began with one of the first examples of community participation and rapid assessment in public health history--the use of pre-franked envelopes to return disease questionnaires and suspect snails from rural areas. This approach quickly and accurately delineated the endemic area. This was Mao Zedong's "mass line", incorporating ideas and knowledge from peasants directly into services run for and by them, here the schistosomiasis control programme. Recognition by China's leaders that schistosomiasis was a great economic burden, steadfast prioritizing of the programme over 40 years, local innovative scientific study, agricultural and environmental focus on eradicating the snail hosts and boosting rural production, and mass community education and support were all key factors in the final success. Local leaders motivated programme staff and everyone involved knew the objectives. The programme was always multisectoral, with policy developed centrally, and strategy and collaboration encouraged and rewarded at the grass-roots. These features explain how a very poor autonomous region such as Guangxi finally eradicated schistosomiasis, spending less than US$ 0.50 per protected citizen per year; it is remarkable that the disease and snails were initially found across a large area of complex environments and modern drugs such as praziquantel were not available for most of the 40-year period. The lessons from Guangxi can be adapted elsewhere and should encourage other areas to control endemic schistosomiasis using methods devised to suit the local culture and geography.

China↗
PubMed1998

A web-based risk management and medical-legal curriculum for graduate medical education.

An educational Web site on the topic of risk management and medical-legal issues was designed. The site incorporates a 25-question multiple-choice quiz where resident responses were stored in a database for quantitative analysis. Residents who browsed the educational module scored significantly higher on the quiz (81%) than those who did not (62%). The authors conclude that the Web site and accompanying quiz database offer a practical solution for the uniform delivery of risk management in graduate medical education.

Computer-Assisted Instruction↗
PubMed1997

Deciphering a neural code for vision.

Deciphering the information that eyes, ears, and other sensory organs transmit to the brain is important for understanding the neural basis of behavior. Recordings from single sensory nerve cells have yielded useful insights, but single neurons generally do not mediate behavior; networks of neurons do. Monitoring the activity of all cells in a neural network of a behaving animal, however, is not yet possible. Taking an alternative approach, we used a realistic cell-based model to compute the ensemble of neural activity generated by one sensory organ, the lateral eye of the horseshoe crab, Limulus polyphemus. We studied how the neural network of this eye encodes natural scenes by presenting to the model movies recorded with a video camera mounted above the eye of an animal that was exploring its underwater habitat. Model predictions were confirmed by simultaneously recording responses from single optic nerve fibers of the same animal. We report here that the eye transmits to the brain robust "neural images" of objects having the size, contrast, and motion of potential mates. The neural code for such objects is not found in ambiguous messages of individual optic nerve fibers but rather in patterns of coherent activity that extend over small ensembles of nerve fibers and are bound together by stimulus motion. Integrative properties of neurons in the first synaptic layer of the brain appear well suited to detecting the patterns of coherent activity. Neural coding by this relatively simple eye helps explain how horseshoe crabs find mates and may lead to a better understanding of how more complex sensory organs process information.

Animals↗
PubMed1997

IgA immunity in HIV type 1-infected chimpanzees. I. Systemic immunity.

HIV infection in humans causes various aberrancies in both the cellular and humoral immune systems, including functional abnormalities of B lymphocytes. In many instances, dysfunction occurs in the regulation of serum IgA, resulting in elevated concentrations of this immunoglobulin isotype. To determine whether HIV-1-infected chimpanzees develop IgA abnormalities similar to those observed in humans, we quantified total IgA, IgG, and IgM levels in sera collected longitudinally from six HIV-infected chimpanzees and one uninfected control animal. In comparison to immunoglobulin levels in the uninfected animal, two of the six infected chimpanzees exhibited increases in serum immunoglobulins following infection with HIV. Two other infected animals showed a marked decrease in the three isotypes within 10 months of exposure to HIV, followed by a return to baseline levels. The remaining two HIV-infected chimpanzees displayed serum immunoglobulin levels that paralleled the baseline levels and did not show great deviation over a period of 20 to 45 months postinfection. ELISA analyses of the IgA subclasses revealed possible abnormalities of the IgA2 subclass within the two animals that did not display irregular IgA, IgG, or IgM responses to HIV-1. Specific IgG, IgA, IgA1, and IgA2 antibodies to HIV antigens were detected by an enzyme immunoassay (EIA) kit and by Western blot analysis with IgA, IgA1, and IgA2 antibodies directed against the env, gag, and pol gene products. Because IgG can mask the detection of HIV-specific IgA antibodies in infected humans, Western blots and EIAs were also performed on IgG-depleted chimpanzee sera. The results demonstrated that in some instances, IgA reactivity against HIV antigens can be enhanced on removal of IgG. This study indicates that HIV-1 is capable of inducing abnormalities in serum IgA expression in chimpanzees. These results might further understanding of how HIV affects humoral responses in infected humans.

Animals↗
PubMed1997

IgA immunity in HIV type 1-infected chimpanzees. II. Mucosal immunity.

Vaginal wash fluids from chimpanzees cervically infected with HIV-1 and saliva from intravenously and cervically infected chimpanzees were analyzed for total IgA, IgA1, IgA2, IgG, and albumin concentrations and for reactivity against HIV-1. No overt abnormalities were detected in salivary immunoglobulin or albumin concentrations in either group of animals. Anti-HIV IgA and IgA subclass antibodies were demonstrated in saliva from five of six intravenously infected chimpanzees and in two of four cervically infected animals, with titers ranging from 1:5 to 1:20. HIV-specific IgG antibodies could be detected in saliva from half of the systemically infected group, the highest titer being 1:2560, whereas the highest anti-HIV IgG titer in the mucosally infected group was 1:20. Western blot analyses of the first saliva samples obtained after initial virus exposure revealed IgG, IgA, and IgA subclass antibodies directed at the env, gag, or pol gene products in both groups of chimpanzees. Examination of IgG, IgA, IgA1, and IgA2 concentrations in vaginal washes from cervically infected animals showed that IgG levels were highest, but IgA and IgA subclass reactivities against HIV-1 were more prominent than that of IgG. These results demonstrate that systemic infection of chimpanzees with HIV-1 elicits mucosal responses specific for HIV, and vaginal infection of chimpanzees induces a common mucosal immune response reminiscent of that in humans.

Albumins↗
PubMed1997

Mental health nursing: making it a primary concern.

This article suggests that the focus of mental health nursing is narrowing at a time when nurses in other areas are widening their roles and responsibilities. The author calls for more co-operation between mental health nurses and their colleagues in primary health care.

Humans↗
PubMed1997

Health effects of caregiving: the caregiver health effects study: an ancillary study of the Cardiovascular Health Study.

We propose that two related sources of variability in studies of caregiving health effects contribute to an inconsistent pattern of findings: the sampling strategy used and the definition of what constitutes caregiving. Samples are often recruited through self-referral and are typically comprised of caregivers experiencing considerable distress. In this study, we examine the health effects of caregiving in large population-based samples of spousal caregivers and controls using a wide array of objective and self-report physical and mental health outcome measures. By applying different definitions of caregiving, we show that the magnitude of health effects attributable to caregiving can vary substantially, with the largest negative health effects observed among caregivers who characterize themselves as being strained. From an epidemiological perspective, our data show that approximately 80% of persons living with a spouse with a disability provide care to their spouse, but only half of care providers report mental or physical strain associated with caregiving.

Activities of Daily Living↗
PubMed1997

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency with the G1528C mutation: clinical presentation of thirteen patients.

Long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase is one of three enzyme activities of the mitochondrial trifunctional protein. We report the clinical findings of 13 patients with long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency. At presentation the patients had had hypoglycemia, cardiomyopathy, muscle hypotonia, and hepatomegaly during the first 2 years of life. Seven patients had recurrent metabolic crises, and six patients had a steadily progressive course. Two patients had cholestatic liver disease, which is uncommon in beta-oxidation defects. One patient had peripheral neuropathy, and six patients had retinopathy with focal pigmentary aggregations or retinal hypopigmentation. All patients were homozygous for the common mutation G1528C. However, the enoyl-CoA hydratase and 3-ketoacyl-CoA thiolase activities of the mitochondrial trifunctional protein were variably decreased in skin fibroblasts. Dicarboxylic aciduria was detected in 9 of 10 patients, and most patients had lactic acidosis, increased serum creatine kinase activities, and low serum carnitine concentration. Neuroradiologically there was bilateral periventricular or focal cortical lesions in three patients, and brain atrophy in one. Only one patient, who has had dietary treatment for 9 years, is alive at the age of 14 years; all others died before they were 2 years of age. Recognition of the clinical features of long-chain 3-hydroxyacyl-CoA deficiency is important for the early institution of dietary management, which may alter the otherwise invariably poor prognosis.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1997

The patient with an overactive bladder--symptoms and quality-of-life issues.

OBJECTIVES: Psychosocial adjustment to illness is an important as the status of the physical disease itself; focusing on this necessitates some measurement of abstract, subjective feelings of "quality of life" (QOL). Assessments of QOL are particularly important for conditions such as urinary incontinence (UI) that have little or no impact on mortality. METHODS: This presentation describes the reasons for, and methods of, measuring lower urinary tract symptoms and disease impact. Validated instruments available for such measurements are reviewed, as are published studies that address the impact of UI (and urge incontinence in particular) on QOL. Potential applications for these new disease measures are discussed. RESULTS: The bladder is an unreliable witness, and symptom assessment is diagnostically disappointing; cystometry is essential if a definitive diagnosis is required. However, objective tests take no account of the patient's perception of the problem. General health status questionnaires have been used to show that urge incontinence is associated with emotional problems, reduced social and recreational activity, and sexual dysfunction. Newly developed, condition-specific instruments have greater specificity and, hence, improved sensitivity for measuring incontinence and its impact. These instruments have the potential for monitoring disease progression and evaluating treatment outcome. CONCLUSIONS: In a proportion of people with bladder overactivity, the disorder has a profound impact on the QOL. Methods of measuring this impact have been developed that may allow identification of this group of individuals while also improving the assessment of treatment efficacy. However, this science is in its infancy and these dimensions await further exploration.

Female↗
PubMed1997

Design, synthesis, and in vitro activities of benzamide-core glycoprotein IIb/IIIa antagonists: 2,3-diaminopropionic acid derivatives as surrogates of aspartic acid.

In an effort to discover novel nonpeptide glycoprotein IIb/IIIa (GPIIb/IIIa, alpha IIb/beta 3) inhibitors, we investigated RGD mimetics featuring a 3-substituted benzoic acid as the core, benzamidine as the basic moiety, and a series of beta- and alpha-substituted beta-alanine derivatives as aspartic acid surrogates. It was found that the use of beta-methyl beta-alanine slightly improved the anti-aggregant potency in human platelet-rich plasma over the unsubstituted beta-alanine compound, while beta-substitution with a trifluoromethyl group resulted in considerable loss in activity. Significant enhancement (up to 100-fold) in potency was obtained when the beta-alanine was replaced with N2-substituted 1-2,3-diaminopropionic acid derivatives. Among the three types of alpha-substituents (carbamate, amide, and sulfonamide) investigated, no apparent preference was observed with respect to in vitro potency. However, alkyl groups were more favorable than arylalkyl groups (Cbz) in the carbamate analogues. We also investigated piperidine, piperazine, and N-formamidinopiperidine as replacements for the benzamidine moiety. The former two replacements led to a drop in potency while the latter replacement resulted in maintenance of activity as compared with the corresponding benzamidine analogue.

Alanine↗
PubMed1997

Cloning and expression analysis of a gene that shows developmental regulation upon tuberization in potato.

Differential screening of a potato leaf cDNA library with cDNA probes made from tuberizing and non-tuberizing Solanum demissum plants led to the identification of a clone that is upregulated in leaves and other tissues upon tuberization. This clone was also shown to have a high level of expression in green tomato fruit, its expression falling off as the fruit turns red. No sucrose or hormonal regulation of the expression of this clone was observed and it did not respond to wounding or heat stress. Clone 32B is 532 bp long and contains an open reading frame encoding a small protein of 98 amino acids. The deduced protein sequence has a putative signal peptide for ER transport and a 10 amino acid domain in the C-terminal region of the protein, both of which are also found in the cotton LEA5, Arabidopsis Di21 and the mungbean Arg2 proteins.

Amino Acid Sequence↗
PubMed1997

Does organizational culture affect out-patient DNA (did not attend) rates?

Government interest in health service "did not attend" (DNA) rates was seen to occur by accident, following which efforts to reduce DNAs have tended to concentrate on operational rather than strategic issues. Considers the effect hospital culture has had on DNA rates from an organizational and patient perspective. Identifies some of the key cultural issues that impacted on DNA rates by utilizing observation and telephone survey research methods. Concludes that, in the main, the lack of customer-oriented organizational culture was seen to affect DNA rates adversely within one NHS provider trust.

Appointments and Schedules↗
PubMed1997

The management of cervical carcinoma within the south west region of England. Expert Tumour Panel.

OBJECTIVE: 1. To audit the management of cervical carcinoma in the South West Region with the aim of identifying and addressing deficiencies. 2. To determine whether recent NHS restructuring has affected the provision of cancer care. DESIGN: Retrospective review of hospital case notes. SETTING: All hospitals in the South West Region of England. POPULATION: Three hundred and twenty-four women with a diagnosis of cervical carcinoma: 191 were diagnosed in 1989 and 133 in 1993. MAIN OUTCOME MEASURES: Documentation of patient assessment and management. RESULTS: There was a mean delay of 17 days (range 0-66) from cervical smear to cytology report and 34 days (range 1-380) from general practitioner referral to attendance at a hospital clinic. Overall, 175 women (54%) had evidence of cytological assessment prior to treatment and 137 (42%) had a colposcopic assessment; 49% had cytological assessment and 37% had colposcopy in 1989, compared with 60% and 50%, respectively, in 1993. Excluding 49 cases of micro-invasive carcinoma, 238 case notes (86%) contained evidence of clinical examination; 195 women (71%) had had an examination under anaesthesia, 115 (42%) a chest radiograph, 123 (45%) an intravenous urogram or renal ultrasound, and 92 (33%) cystoscopy. One hundred and forty-seven women (53%) had FIGO staging recorded in the notes. As first line treatment, 69 had conservative surgery (39 for Stage IA), 138 had radiotherapy, and 107 had radical surgery. Ten had radical surgery for Stage IA but eight had a > 3 mm invasion or lymphatic/vascular spread. Thirty-one had Stage IB treated with radiotherapy of whom 14 were younger than 50 years of age. Following radical surgery 30% had evidence of sampling > or = 10 nodes, and 9% had tumour extending to the resection margins. CONCLUSIONS: Record keeping was inadequate but appeared to indicate inconsistent cytological, clinical, colposcopic and radiological assessment, leading to inappropriate clinical delays and conservative surgery. Radical surgery often appeared inadequate, but poor node sampling rates may also reflect insufficient histopathological preparation or reporting. There was a reduction in the number of new cases of cervical carcinoma diagnosed in 1993, perhaps reflecting an observed increase in cytological surveillance. No other alterations in clinical practice were observed over the four-year period. We feel it is imperative to standardise assessment throughout the region with a minimum clinical and histopathological dataset.

Adult↗