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S Watts

Publications and source records attributed to S Watts.

At least 55 records · Page 3Linked to original sources
PubMed1998

Perceptions and priorities in disease eradication: dracunculiasis eradication in Africa.

Dracunculiasis, guinea worm disease, is an incapacitating disease affecting people in poor, remote areas of Africa, in Yemen, and a few remaining areas of the Indian subcontinent where there is poor access to protected water sources. The neglect of this preventable disease and its belated recognition are analyzed within the context of changing priorities for health since the 1870s, especially the shift from the paradigm of Imperial Medicine to Primary Health Care. A global eradication effort took off during the 1980s, and, although the original target date of December 1995 has passed, the program has achieved a remarkable recent diminution in the number of recorded cases, over 99% of which are now found in Africa. Eradication policies in Africa are briefly explored in relation to current concerns such as the incorporation of dracunculiasis eradication measures in cash-starved primary health care programs. The wider implications of an eradication campaign which is on the verge of success are also considered.

Africa↗
PubMed1998

An ancient scourge: the end of dracunculiasis in Egypt.

This paper addresses the question of when guinea worm disease was last found in Egypt, and how written sources from the nineteenth and twentieth centuries which mention the disease should be evaluated. This enquiry is relevant to the global eradication campaign now in progress, and the need for countries in which dracunculiasis was once present to prepare a certification of eradication. Sudan, the country which has the largest number of cases today, is Egypt's southern neighbour. Because of the nature of the disease (in endemic areas it is most common among poor, rural people), it may not have come to the attention of urban-based health personnel. In the period before the details of the transmission cycle were known, the attitudes and mindsets of physicians and travellers also have to be taken into account in interpreting written reports of the disease. An examination of documentary sources from the nineteenth and twentieth centuries in European languages does not show any clear evidence for dracunculiasis transmission in Egypt during that period. Cases noted in Egypt, especially by the much quoted Dr Clot Bey in the 1820s, most likely originated beyond the borders of the country, in Sudan and, to a lesser extent, from endemic areas in the Middle East. However, many later commentators merely repeated what Clot Bey had written. A further difficulty is that some published reports which apparently concern dracunculiasis in Egypt, actually refer to cases in animals rather than humans.

Animals↗
PubMed1998

Schistosomiasis screening and health education for children: action research in Nile delta villages.

In Egypt an important component of the national schistosomiasis control policy is the regular screening of school children through the rural health units. In the Nile delta, a major challenge for the programme is the increasing predominance of Schistosoma mansoni, as compared to Schistosoma haematobium over the past 20 years, and the need to adjust strategies to this new reality. The action research project, growing out of an in-depth study of schistosomiasis in two Nile delta villages, is intended to provide recommendations for schistosomiasis control to the Egyptian Ministry of Health and Population. This paper explores the practice of school-based screening. We then describe the designing and testing of a revised screening procedure, which focuses on the collection of stool specimens to diagnose S. mansoni and which is comprehensive and gender-sensitive. Opportunities for health education are discussed briefly, as this is necessary for an effective screening procedure and to prevent reinfection. In conclusion, we mention the need to incorporate screening and health education into an integrated control strategy

Adolescent↗
PubMed1998

Identification of missense and truncating mutations in the BRCA1 gene in sporadic and familial breast and ovarian cancer.

The cloning of the breast and ovarian cancer susceptibility gene, BRCA1, allows direct estimation of the proportion of these cancers in the general population which can be attributed to germline mutations in this gene. We have used a combination of SSCP, heteroduplex analysis, and chemical cleavage of mismatch to screen the BRCA1 gene for mutations in the germline of 42 patients with breast or ovarian cancer who either have a moderate family history of these cancers, or have no family history of malignancy but a very early onset of the disease. A total of 30 sequence variants were observed, eight of which have not been described previously. Three sequence changes detected by chemical cleavage or heteroduplex analysis were missed by SSCP. The variants included 13 missense mutations, which were assessed for their pathogenic implications. Two of these (M18T and A1708E) are nonconservative substitutions which are located in evolutionarily conserved regions of the gene: M18T lies just upstream of the RING finger motif, and A1708E abolishes the transcriptional transactivation activity of the carboxy-terminal region of BRCA1. Mutations were observed in eight patients overall (19.0%), and protein-truncating mutations occurred in five of 27 (18.5%) families with 1-3 cases of breast or ovarian cancer. The data suggest that a significant proportion of patients with a modest or no family history of these cancers may carry germline mutations in BRCA1.

Adult↗
PubMed1997

Protein tyrosine kinase involvement in the production of superoxide anion by neutrophils exposed to Aroclor 1242, a mixture of polychlorinated biphenyls.

Neutrophils produce superoxide anion (O2-) when exposed in vitro to Aroclor 1242, a mixture of polychlorinated biphenyls (PCBs). The mechanism for this effect shares some similarities with the mechanism by which the physiologic agonist f-Met-Leu-Phe (fMLP) activates neutrophils. Since production of O2- in response to fMLP involves GTP-binding proteins and protein tyrosine kinases (PTKs), the current study was undertaken to determine whether these signalling pathways are involved in PCB-induced neutrophil activation. Neutrophils exposed to Aroclor 1242 or fMLP produced significant O2-. Pretreatment of intact neutrophils with pertussis toxin or cholera toxin or exposure of permeabilized cells to GDPbetaS significantly inhibited O2- production in fMLP-treated neutrophils but did not alter the response to Aroclor 1242. Pretreatment with genistein, an inhibitor of PTKs, significantly inhibited O2- production in both Aroclor 1242- and fMLP-treated neutrophils; however, daidzein, a structural analogue of genistein which lacks activity against PTKs, was without effect. Exposure of neutrophils to Aroclor 1242 resulted in an increase within 1 min in tyrosine phosphorylation of proteins in the 40 and 60 kDa molecular mass ranges which persisted for up to 10 min. Similar results were obtained with 2,2',4,4'-tetrachlorobiphenyl (2,2',4,4'-TCB), a PCB congener that stimulates O2- production. In contrast, 3,3',4,4',5-pentachlorobiphenyl (3,3',4,4',5-PeCB), a congener that does not generate O2-, caused only a transient increase in tyrosine phosphorylation of proteins in the 40 kDa range with no effect on 60 kDa proteins. These data suggest that Aroclor 1242 activates neutrophils to produce O2- by a mechanism that requires tyrosine kinase activity; however, heterotrimeric G-proteins are not likely to be involved.

Animals↗
PubMed1997

Patients' perceptions of the pre-operative information they need about events they may experience in the intensive care unit.

Through a descriptive survey, this study examined the pre-operative information which patients need about the events they may experience in intensive care, when they are admitted there following elective surgery. A subsidiary aim was to find out how they felt this information should be delivered. Questionnaires were posted to a convenience sample of 57 people who had been admitted post-operatively to one ICU in the past year. Forty-three (75%) of the questionnaires were returned and were analysed with the five returned in the pilot study. The results suggested that pre-operative information about ICU was perceived helpful by all respondents, particularly the management of pain and nausea, the likely site of pain, mouth care, the high nurse:patient ratio and having a urinary catheter. Information rated helpful less frequently, included noise levels, visiting times and men and women being nursed in the same room. The most popular method for receiving the information was via a pre-operative visit from a nurse working in ICU. In view of the sampling procedure and the validity of data collection methods, these findings cannot be generalized.

Adaptation, Psychological↗
PubMed1997

Schistosomiasis in two Nile delta villages: an anthropological perspective.

In the rapidly changing Nile delta villages, applied research for schistosomiasis control requires a holistic view of the social and environmental setting of the disease. An interdisciplinary, participatory study of two delta villages studied human behaviour in relation to disease transmission, knowledge and treatment using the insights and methods of social science, especially anthropology. Through primarily qualitative techniques such as focus group discussions and participant observation, we found that most people who used the canals for domestic, recreational or agricultural activities thought that they had little alternative but to do so, even though they knew of the risk of exposure to schistosomiasis. The knowledge and behaviour of villagers with regard to schistosomiasis affected their utilization of the local provisions for schistosomiasis diagnosis and treatment. Our monitoring of diagnosis and testing for schistosomiasis at a local health centre identified areas which could be upgraded, and we trained health staff to improve their knowledge of schistosomiasis. Our findings reinforce the need for integrated research and implementation strategies, taking into account the knowledge and capabilities of all those involved in schistosomiasis control at the village level, and the fostering of effective communication between villagers, both women and men, and the local staff in rural health centres.

Adolescent↗
PubMed1997

In vitro effects of diazepam on human ciliary function.

This study demonstrated the in vitro effect of diazepam on human ciliary beat frequency (CBF) from fifteen normal subjects using brush cytology. Tube A contained culture medium, tube B the diluent that diazepam intravenous injectate was carried in and culture medium (controls). Tube C, D and E contained, 0.4 mg/l, 4.0 mg/l and 40.0 mg/l of diazepam in culture medium respectively. The mean effective diazepam concentration in plasma is 0.4 mg/l. CBF was measured photometrically. The most vigorous cilia were measured in 5 areas taking 10 readings on each sample, 30 minutes and 1 hour after mixing. Standard deviation (SD) and confidence limits were calculated along with significance testing (p < 0.05) using the paired t-test and ANOVA. The mean of the CBF of tubes A and B were 13.44 (SD 2.65) and 13.67 (SD 2.48). There was a reduction of the CBF with increasing concentrations of diazepam at 30 minutes, 11.32 (SD 2.14), 10.29 (SD 1.58) and 4.14 (SD 1.57) tubes C. D and E respectively. There was a significant lowering in CBF of 17% (p < 0.01) of diazepam at the mean effective plasma level (tube C) when compared against the controls. CBF decreased over time and at 1 hour was 10.57 (SD, 1.36), 9.02 (SD, 1.39) and 3.58 (SD, 1.31) tubes C, D and E respectively. A proposed mechanism of altered intracellular calcium flux via the action diazepam on GABA receptors is described.

Adult↗
PubMed1996

Finger flexion does not contribute to ball speed in overarm throws.

The aim of this study was to determine whether, in overarm throws made by recreational ball players, the fingers undergo flexion movement before ball release and thereby contribute to the generation of ball speed. To obtain the high resolution needed to answer this question, the magnetic-field search-coil technique was used and the data were sampled at 1000 Hz. The subjects, who were either seated or were standing, threw tennis balls at different speeds at a target 3 m away. Angular positions in three dimensions were simultaneously recorded of the distal phalanx of the middle finger and hand and, in additional experiments to determine the mechanism of ball release in more detail, three middle finger phalanges and the hand. Different phases of ball release were determined by pressure-sensitive microswitches on the proximal and distal phalanges of the middle finger. Irrespective of whether the subjects were seated or were standing, for all throws at all speeds, finger flexion did not occur before ball release. That is, up until final release of the ball, the fingers only underwent extension associated with hand opening. For fast throws, at the instant of final ball release the fingers began to flex, presumably as a result of reactive forces associated with release of the ball. Thus, in overarm throws made by recreational ball players, finger flexion movement does not appear to contribute to the generation of ball speed.

Adult↗
PubMed1996

Errors in the control of joint rotations associated with inaccuracies in overarm throws.

1. Accurate overarm throwing requires precise control of joint rotations so that the ball is released at the appropriate time on the appropriate hand trajectory. Inaccuracy in throws, in turn, must result from errors in the control of joint rotations. But do high and low throws result from disorders in the joint rotations that produce the hand trajectory or in those that cause ball release? Are they due to error at a particular joint or to accumulation of errors across a number of joints? The objective was to answer these questions and thereby to gain insight into the CNS control of joint rotations in a skilled arm movement task. 2. Ten subjects--male, right-handed recreational ball players, all accurate throwers--sat with a fixed trunk and threw tennis balls at a 9 x 9 grid of 6-cm target squares 1.5 or 3 m away. Rotations of five arm segments in three dimensions were measured at 1,000 Hz with the magnetic-field search-coil technique. Hand trajectory (translation) was computed from these rotations. 3. The cause of ball high-low inaccuracy was investigated by determining its relation with hand kinematic parameters that could potentially affect it. No statistically significant relation was found between height of ball impact on the target and height of the hand trajectory. In contrast, statistically significant relations appeared between height of ball impact on the target and both hand trajectory length at ball release (for 8 of 10 subjects) and finger and hand orientation in space at ball release (for all 10 subjects). 4. Three hypotheses were proposed to explain the variable finger and hand orientations in space at ball release, i.e., that they resulted from errors in velocity of rotation at one or more proximal joints (wrist, elbow, shoulder), timing of onset of rotation at one or more proximal joints, or timing of ball release (due to incorrect velocity or timing of onset of finger opening). All three mechanisms could result in inappropriate finger and hand orientations in space at ball release, but the pattern of joint space trajectories would be different in each case. 5. High and low throws did not follow the joint space paths predicted by the first two hypotheses. Instead, as predicted by the third hypothesis, a separation of traces occurred when finger extension was plotted against wrist flexion or against elbow extension, e.g., for a given amplitude of wrist flexion, finger extension was large for the high throws and small for the low throws. 6. In agreement, when all throws were considered, a statistically significant (P < 0.005) relation was found between ball impact height on the target and the amplitude of finger extension, for a fixed amplitude of wrist flexion (10 subjects), and for a fixed amplitude of elbow extension (8 subjects). Only two subjects showed a statistically significant relation between ball impact height and the amplitude of wrist flexion, for a fixed amplitude of elbow extension. 7. The separation of finger extension-wrist flexion traces in joint space for high and low throws was due to a difference in the timing of onset of finger rotation with respect to the wrist rather than to an inappropriate velocity of the finger (or the wrist). 8. As expected, all 10 subjects showed statistically significant relations between the time of onset of finger extension and both finger orientation in space at ball release and height of ball impact on the target. 9. It is concluded that in fast arm-only throws made by male recreational ball players, high and low throws do not primarily result from variability in the height of the hand trajectory or from variability in the amplitude of one or more proximal joints due to errors in the velocity or timing of onset of these joint rotations. Instead, in most cases, they result from inappropriate timing of onset of rotation of the fingers with respect to the rotations of the other joints and thus to inappropriate timing of ball release. These findings emphasize the im

Arm↗
PubMed1996

Overarm throws with the nondominant arm: kinematics of accuracy.

1. Overarm throws made with the nondominant arm are usually less accurate than those made with the dominant arm. The objective was to determine the errors in the joint rotations associated with this inaccuracy, and thereby to gain insight into the neural mechanisms that contribute to skill in overarm throwing. 2. Overarm throws from both left and right arms were recorded on different occasions as six right-handed subjects sat with a fixed trunk and threw 150 tennis balls at about the same speed at a 6-cm square on a target grid 3 m away. Joint rotations at the shoulder, elbow, wrist, and finger, and arm translations, were computed from recordings of arm segment orientations made with the magnetic-field search-coil technique. 3. All subjects threw less accurately in this task with the left (nondominant) arm. For throws made with the left arm, the height of ball impact on the target grid was related to hand trajectory length and to hand orientation in space at ball release, but not to hand trajectory height. 4. Two hypotheses were proposed to explain the decreased ball accuracy in the high-low direction during throwing with the nondominant arm: that it was caused by increased variability in the velocity or timing of onset of rotations at proximal joints (which determine the path of the hand through space) or increased variability in the velocity or timing of onset of finger extension (which determine the moment of ball release). 5. A prediction of the first hypothesis was that proximal joint rotations should be more variable in throws with the left arm. This was the case for the majority of proximal joint rotations in the six subjects when variability was examined in joint space. However, some proximal joint rotations were more variable in the right arm. 6. The first hypothesis was directly tested by determining whether hand angular position in space (which represents the sum of all proximal joint rotations) was related to ball impact height on the target grid at a fixed translational position in the throw. No relation was found between these variables for throws with the left arm in four subjects, whereas a weak relation was found for two subjects. It was concluded that, considering all subjects, the first hypothesis could not explain the results. 7. In contrast, in agreement with the second hypothesis, a strong relation (P < 0.001) was found in all subjects between ball impact height on the target grid and time of ball release for throws with the left arm, and with time of onset of finger extension. 8. Across all six subjects the timing precision (windows) for 95% of the throws was (for ball release) right arm, 9.3 ms; left arm, 22.5 ms; (for onset of finger extension) right arm, 13.7 ms; left arm, 26.7 ms. 9. Timing of onset of finger extension was no less accurate than timing of onset of other joint rotations for both left and right arms. However, simulations of throws showed that, for the same error in timing, finger extension had twice as large an effect on ball direction as any other joint rotation. Timing errors at the fingers have a greater effect than errors at other joints because finger errors are scaled by the higher angular velocity of the hand in space rather than by the smaller angular velocities of the individual joints. 10. It is concluded that although rotations were in general more variable at both proximal and distal joints of the nondominant (left) arm, the major cause of its decreased throwing accuracy was increased variability at the distal joints, i.e., in the timing of onset of finger extension. This may be due to a lack of precision in the commands from the right hemisphere to the left fingers in right-handed throwers.

Arm↗
PubMed1996

No transmission of dracunculiasis in Egypt for two centuries.

Despite occasional assertions to the contrary, no convincing evidence has been found of guinea-worm disease (dracunculiasis) being transmitted in humans in Egypt during the nineteenth and twentieth centuries. The confusion appears to be caused mainly by imported cases and the incidence of the disease in animals.

Animals↗
PubMed1995

Timing of finger opening and ball release in fast and accurate overarm throws.

How precisely does the CNS control the timing of finger muscle contractions in skilled movements? For overarm throwing, it has been calculated that a ball release window of less than 1 ms is needed for accuracy in long throws. The objective was to investigate the timing precision of ball release and finge opening for 100 overarm throws made using only the arm. Subjects sat with a fixed trunk and threw balls fast and accurately at a 6-cm-square target when it was 1.5, 3.0 and 4.5 m away. Three-dimensional angular positions in space of the clavicle, upper arm, forearm, hand and distal phalanx of the middle finger were simultaneously recorded at 1000 Hz using the magnetic-field search-coil technique. Ball release was determined by pressure-sensitive microswitches on the proximal and distal phalanges of the middle finger (proximal and distal triggers). Variability of ball release, defined in terms of the standard deviation (SD) of the means of release times, was different when synchronized to different hand kinematic parameters. It was highest to the start of movement (when the hand started rotating vertically forward and up around a space-fixed horizontal axis) and was lowest when synchronized to the moment near ball release when the hand was vertical. These values did not depend on target distance. When throws were synchronized to vertical hand position, and SDs were averaged across the 10 subjects, the average interval for 95% of the throws (4xSD) was 9.6 ms for ball release and 10.0 ms for onset of finger opening. Thus, two independent measures of timing precision gave similar results. It is concluded that for 100 fast and accurate throws made by male recreational ball players, timing of finger opening and ball release was controlled precisely but not to fractions of a millisecond.

Adult↗
PubMed1995

Schistosomiasis control through rural health units.

In Egypt the main effort in the campaign against schistosomiasis involves providing free diagnosis and treatment through primary care facilities, especially rural health units. The prospects for improving these services are considered below.

Child↗
PubMed1995

The public health implications of the increasing predominance of Schistosoma mansoni in Egypt: a pilot study in the Nile delta.

Over the past twenty years, Schistosoma mansoni has apparently replaced Schistosoma haematobium as the more prevalent species of schistosomiasis in the Nile delta. In this paper we show that this change has profound implications for public health strategies, in particular the provision and utilization of diagnostic and treatment services for the Egyptian rural population, and for health education programmes. The processes of providing and seeking treatment for the two forms of schistosomiasis are quite distinct as they have different signs and symptoms and are diagnosed in stool and urine samples respectively. In two Nile delta villages, where S. mansoni has almost completely replaced S. haematobium, we found that health services were geared primarily to S. haematobium, and hence many cases of S. mansoni remain undiagnosed and untreated. One reason for this is that health unit staff and local people lacked detailed knowledge of the two forms of schistosomiasis, indicating the need for health education.

Egypt↗
PubMed1994

The incidence of pressure sores within a National Health Service Trust hospital during 1991.

The prevalence of pressure sores has been frequently reported. However, such measures fail to identify how many patients develop sores, while longitudinal changes in prevalence rates are difficult to interpret. This paper provides the first report of the incidence of pressure sores across the population of a single NHS Trust hospital. During 1991, 360 patients developed sores, an incidence of 4.03 patients per 100 admissions. Within orthopaedic wards, the incidence was higher, with 10.3 patients per 100 admissions developing sores.

England↗
PubMed1994

Partners of problem drinkers: moving into the 1990s.

The literature on partners of problem drinkers is reviewed. Originally research and treatment viewed partners of problem drinkers from a pathological perspective. This paper suggests an alternative stress and coping perspective as less stigmatizing and more realistic in terms of the experiences of these individuals.

Journal Article↗