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S Coates

Publications and source records attributed to S Coates.

At least 19 recordsLinked to original sources
PubMed2006

Dissolved oxygen as a physico-chemical supporting element in the Water Framework Directive.

For transitional and coastal waters the Water Framework Directive identifies 5 "General chemical and physiochemical elements supporting the biological elements". The five elements are transparency, thermal conditions, oxygenation conditions, salinity and nutrient conditions. "Supporting" in the context of the directive means that the values of the physicochemical quality elements are such as to support a biological community of a certain ecological status, recognising the fact that biological communities are products of their physical and chemical environment. Physicochemical and hydromophological aspects fundamentally determine the type of water body and habitat, and hence the type specific biological community. The directive does not intended that these supporting elements should be used as surrogates for the biological elements in monitoring. The monitoring and assessment of the physical and physicochemical quality elements will support the interpretation, assessment and classification of the results arising from the monitoring of the biological quality elements. This paper considers the challenges involved in the development of oxygen standards for the directive, their relationship to the biological elements and normative conditions of the directive and to regulatory requirements.

Ecosystem↗
PubMed2000

The strength-duration curve and its importance in pacing efficiency: a study of 325 pacing leads in 229 patients.

Pacemaker battery life is dependent on programmable parameters, principally pulse amplitude and pulse duration. High factory default settings cause excessive current drain. The strength-duration curve relates pacing threshold to pulse duration. The most energy efficient pacing occurs at chronaxie, a value of pulse duration derived from the curve. Strength-duration curves were calculated for 325 acutely implanted pacing leads. Chronaxie and rheobase were compared for atrial and ventricular leads. Chronaxie was compared with actual programmed pulse duration. There were 101 atrial and 224 ventricular leads, all passive fixation. The curve fit was good, (mean error +/- SD) 0.024 +/- 0.06 V for atrial curves and 0.008 +/- 0.034 V for ventricular curves. Mean (+/- SD) atrial and ventricular chronaxies were 0.24 +/- 0.07 ms and 0.25 +/- 0.07 ms, respectively. A "Z" value of 1.4 indicated that chronaxies might have been from the same population. Mean (+/- SD) atrial and ventricular rheobases were 0.51 +/- 0.2 V and 0.35 +/- 0.13 V, respectively. A "Z" value of 7.1 (P < 0.001) suggested atrial and ventricular rheobases were from differing populations. All patients had factory default pulse durations of 0.45 ms or 0.5 ms, exceeding acute chronaxie by a factor of two, thus, demonstrating suboptimal pacing. We conclude that understanding the strength-duration curve is critical. Sensible programming of other pacing functions optimizes longevity. Battery drain is reduced by programming pulse duration to chronaxie with a doubling of voltage threshold at this point to achieve a safety margin. Further study of chronaxie drift with time is required.

Adult↗
PubMed2000

Evaluation of hepatitis C virus glycoprotein E2 for vaccine design: an endoplasmic reticulum-retained recombinant protein is superior to secreted recombinant protein and DNA-based vaccine candidates.

Hepatitis C virus (HCV) is the leading causative agent of blood-borne chronic hepatitis and is the target of intensive vaccine research. The virus genome encodes a number of structural and nonstructural antigens which could be used in a subunit vaccine. The HCV envelope glycoprotein E2 has recently been shown to bind CD81 on human cells and therefore is a prime candidate for inclusion in any such vaccine. The experiments presented here assessed the optimal form of HCV E2 antigen from the perspective of antibody generation. The quality of recombinant E2 protein was evaluated by both the capacity to bind its putative receptor CD81 on human cells and the ability to elicit antibodies that inhibited this binding (NOB antibodies). We show that truncated E2 proteins expressed in mammalian cells bind with high efficiency to human cells and elicit NOB antibodies in guinea pigs only when purified from the core-glycosylated intracellular fraction, whereas the complex-glycosylated secreted fraction does not bind and elicits no NOB antibodies. We also show that carbohydrate moieties are not necessary for E2 binding to human cells and that only the monomeric nonaggregated fraction can bind to CD81. Moreover, comparing recombinant intracellular E2 protein to several E2-encoding DNA vaccines in mice, we found that protein immunization is superior to DNA in both the quantity and quality of the antibody response elicited. Together, our data suggest that to elicit antibodies aimed at blocking HCV binding to CD81 on human cells, the antigen of choice is a mammalian cell-expressed, monomeric E2 protein purified from the intracellular fraction.

Animals↗
PubMed1999

Exposure of sows to Ascaris suum influences worm burden distributions in experimentally infected suckling piglets.

This paper reports on the influence of maternal exposure to Ascaris suum on worm burden distributions in experimentally infected piglets. In the first study, sows were inoculated before and during gestation (6 months, long-term exposure) with 10,000 A. suum eggs twice weekly. In a second study, sows were inoculated during gestation only (3 months, short-term exposure) with increasing doses of eggs (10,000-40,000 eggs twice weekly). Helminth-naive sows served as controls in both studies. The third study used the same design as the short-term exposure study, but piglets from exposed and control sows were cross-suckled within 4 h of birth before colostrum uptake. All piglets were inoculated 2 or 3 times with 50 A. suum eggs on days 4 and 7 (and 14) after birth, and left with the sows. At 10 weeks of age all piglets were necropsied, and liver lesions and worm burdens were recorded. Surprisingly, in piglets born to long-term exposed sows, the prevalence of A. suum infection and the mean worm burden were significantly higher than those in piglets from control sows. In contrast, neither worm burdens nor prevalence were significantly different between piglets from short-term exposed sows compared with their controls. In the cross-suckling experiment, 67% of piglets suckling control sows harboured worms at slaughter, compared with 15% of piglets suckling exposed sows. Maximum likelihood analysis of worm burden distribution and the degree of parasite aggregation showed 3 distinctly different types of overdispersed distributions: worm counts in piglets from control sows, in piglets from short-term exposed sows and in piglets from long-term exposed sows. When the worm burden data were analysed including the cross-suckled piglets by biological mother, it appeared that the control and short-term distributions converged and that only the long-term exposure was significantly different. Overall, the degree of parasite aggregation in piglets infected with A. suum decreased with exposure of the sows. A non-linear relationship was observed between prevalence of infection and mean worm burden, which was different for piglets from exposed and control sows, and similar to relationships of this type that previously have been found in human A. lumbricoides infections. It was concluded that in porcine A. suum infections maternal exposure alters the distribution of worms in their offspring, in which the duration of exposure appeared to be an important influence. The results of the cross-suckling further suggest that maternal factors, e.g. antibodies, are transferred via colostrum.

Animals↗
PubMed1998

A strategy for reducing the mortality rate from vasa previa using transvaginal sonography with color Doppler.

Vasa previa is a cause of sudden unanticipated fetal death, with a fetal mortality of 33-100%. Transvaginal sonography (TVS) and color Doppler may aid in making the diagnosis antenatally, allowing elective Cesarean delivery, thereby avoiding fetal death from exsanguination which would occur if the membranes were allowed to rupture in labor. Whilst it is not feasible to screen all pregnant women for vasa previa, antenatal examination with TVS and color Doppler of women at risk, specifically those with low-lying placentas, bi-lobed, multi-lobed and succenturiate-lobed placentas, multiple pregnancies and pregnancies resulting from in vitro fertilization may lead to antenatal diagnosis of the condition. We present the last three cases of vasa previa to have occurred in our institution, two of which were diagnosed antenatally using TVS and color Doppler. In all three cases, routine 20-week obstetric sonography revealed low-lying placentas; in only one of these did the placenta remain low at term. A low-lying placenta at 20 weeks may be a risk factor for vasa previa; we suggest that further studies be carried out to ascertain this. Judicious use of TVS and color Doppler in women considered at risk of vasa previa may help to reduce the mortality from this condition.

Cesarean Section↗
PubMed1997

Phase II trial of tirapazamine combined with cisplatin in chemotherapy of advanced malignant melanoma.

PURPOSE: A phase II study was undertaken to determine the efficacy of tirapazamine (TPZ) combined with cisplatin (cDDP) in patients with metastatic melanoma. PATIENTS AND METHODS: Between June 1994 and November 1995, 48 patients with metastatic melanoma were treated with TPZ (260 mg/m2, administered intravenously over two hours) followed in one-hour by cDDP (75 mg/m2 over one hour) every 21 days. Sixteen patients had received prior chemotherapy, and 13 of these had failed to respond to prior cDDP. None of the patients had symptomatic brain metastasis. RESULTS: Nine patients had partial responses, with an overall response rate of 19% (95% confidence interval (95% CI) of 9%-33%). The median duration of response was six months. None of the responders had received prior chemotherapy. Responses were seen in 8 (33%, confidence interval of 16%-55%) of 24 patients with primary cutaneous melanoma who had received no prior chemotherapy and in the only patient with previously untreated conjunctival melanoma. There were no responders among the seven patients with choroidal melanoma and 16 patients with previously treated cutaneous melanoma. Two patients with partial responses were rendered free of gross disease surgically three months after completing eight courses of TPZ-cDDP; they remain free of tumor recurrence. Responses were seen in lymph nodes (27%), lung (26%), skin (20%), adrenal gland (20%), soft tissues (17%) and liver (17%). Common toxicities included muscle cramps, fatigue, gastrointestinal effects and peripheral neuropathy. Fatigue, nausea, vomiting, anorexia, and muscle cramps were grade 3 or 4 in less than 10% of the courses. Neutropenia and thrombocytopenia were rare. CONCLUSION: The TPZ-cDDP combination has definite activity against chemotherapy-naïve patients with cutaneous melanoma and warrant further studies in combination with other cytotoxic agents.

Adult↗
PubMed1997

Sibling sex ratio of boys with gender identity disorder.

Sibling sex ratio (the ratio of brothers to sisters) was calculated for 444 boys with gender identity disorder (or with behaviors consistent with this diagnosis). The probands were ascertained from several researchers with expertise with this disorder and from the English language case report literature between 1938 and 1995. Among the probands with at least one sibling (N = 333), the results showed that boys with gender identity disorder had a significant excess of brothers to sisters, 131.1:100, when compared with the expected secondary sex ratio of 106:100. The excess of brothers replicated a previous study by Blanchard, Zucker, Bradley, and Hume (1995), in which the sibling sex ratio was 140.6:100. Further analyses showed that the probands were born later relative to their brothers than they were relative to their sisters. These findings are amenable to several psychosocial and biological explanations, which require further investigation.

Child↗
PubMed1996

Compelling evidence for discretionary brain computed tomographic imaging in those patients with mild cognitive impairment after blunt trauma.

OBJECTIVE: To identify computed tomographic-detected intracranial hemorrhage (CTIH) risk factors and outcome in mild cognitive impairment (MCI) blunt trauma patients. METHODS: In 2,587 consecutive patients, 251 (9.7%) had CTIH. RESULTS: Analysis is on 2,252 direct transports with 163 CTIH, because transfers were different (7.2 vs. 26.3%, p < 0.0001). CTIH rates for patients age 14-60 and > 60 years were 6.3 and 15.9%, p = 0.001. In those 14-60 years (n = 2,032), CTIH (n = 128) was independently related to arrival Glasgow Coma Scale (GCS) score and cranial soft tissue injury (CSTI) (p = 0.0001). [table: see text] Craniotomy was < or = 0.6% in each group except GCS score of 13 with CSTI, 7.4%. Of those with CTIH, 98.4% survived. Of those at low risk (GCS score of 14 without CSTI and GCS score of 15), 1,504 had no CTIH. Of these, 64.4% were available for serial cognitive evaluation (noncranial injuries mandated hospitalization; tracheal intubation was not required). In those > 60 years (n = 220), CTIH (n = 35) was independently related to GCS and CSTI (p = 0.003). CTIH for GCS score of 15 without CSTI was 5.8%, but > or = 16% for others. One craniotomy was required. Of those with CTIH, 91.4% survived. CONCLUSIONS: In mild cognitive impairment patients triaged directly to a Level I trauma center, age, arrival GCS score, and cranial soft tissue injury are risk factors for CT-detected intracranial hemorrhage. Neurologic deterioration and death are infrequent. These data strongly suggest that observation and discretionary brain CT imaging are a rational approach for blunt-injury mild cognitive impairment.

Adolescent↗
PubMed1993

Nonaffinity purification of recombinant gp120 for use in AIDS vaccine development.

The gene encoding the major envelope glycoprotein of the HIV-SF2 isolate was engineered for the secretion of recombinant gp120 (rgp120SF2) from permanent Chinese hamster ovary (CHO) cell lines. Cellular production methods were scaled up and a method for purification of the secreted glycoprotein was devised. Mild purification conditions were selected in order to preserve the native structure of the protein. rgp120SF2 exhibits a molecular weight of 120 kDa in reduced or nonreduced SDS gels; thus the polypeptide chain is intact. Deglycosylated rgp120SF2 has the predicted molecular weight of the polypeptide backbone, 54 kDa. Gel-filtration HPLC in a nondenaturing buffer at neutral pH yields a molecular weight estimate of approximately 120 kDa. Purified rgp120 closely resembles authentic viral gp120 by several physical, chemical, and immunochemical tests. rgp120SF2 reacts strongly with human HIV-positive sera, monoclonal antibodies reactive with HIV-SF2 and HIV-MN viral envelope, and a human virus-neutralizing monoclonal antibody that maps to a conserved discontinuous epitope on HIV-1 gp120. Purified rgp120SF2 forms a 1:1 molecular complex with soluble recombinant human CD4 (rCD4) receptor, as demonstrated by gel-filtration HPLC; binding is high affinity (Kd approximately 2 x 10(-9) M).

AIDS Vaccines↗
PubMed1991

Interim report of the DSM-IV Subcommittee on Gender Identity Disorders.

This article summarizes the discussions and recommendations of the DSM-IV Subcommittee on Gender Identity Disorders, a subcommittee of the Child Psychiatry Work Group, regarding diagnostic issues. The issues reviewed include placement in the nomenclature, the concept of a spectrum of gender dysphoria rather than discrete levels of symptomatology, criticisms of current diagnostic criteria, subtyping by sexual orientation, and proposed changes in diagnostic criteria for the current DSM-III-R diagnoses of Gender Identity Disorder of Childhood, Transsexualism, and Gender Identity Disorder of Adolescence or Adulthood, Nontranssexual Type.

Adolescent↗
PubMed1991

Mothers of boys with gender identity disorder: a comparison of matched controls.

This pilot study compared mothers of boys with gender identity disorder (GID) with mothers of normal boys to determine whether differences in psychopathology and child-rearing attitudes and practices could be identified. Results of the Diagnostic Interview for Borderlines and the Beck Depression Inventory revealed that mothers of boys with GID had more symptoms of depression and more often met the criteria for Borderline Personality Disorder than the controls. Fifty-three percent of the mothers of boys with GID compared with only 6% of controls met the diagnosis for Borderline Personality Disorder on the Diagnostic Interview for Borderlines or had symptoms of depression on the Beck Depression Inventory. Results of the Summers and Walsh Symbiosis Scale suggested that mothers of probands had child-rearing attitudes and practices that encouraged symbiosis and discouraged the development of autonomy.

Anxiety, Separation↗
PubMed1989

Indices of psychopathology in the Rorschachs of boys with severe gender identity disorder: a comparison with normal control subjects.

Recent clinical and empirical studies of boys with Gender Identity Disorder (GID) of Childhood suggest that severe behavioral disturbance exists beyond their feminine preoccupations. This study examines the thought organization and object representational paradigms of a sample of GID boys (n = 26) in a blind comparison with a normal subgroup (n = 18). Rorschach test protocols were used to compare the groups along these two more internal measures of personality organization. As hypothesized, the GIC group was found to have more pathological scores than the normal group on the Mutuality of Autonomy (MOA) Scale and a thought disorder hierarchy. The findings suggest that GID boys do not suffer solely from gender symptomatology but are disturbed in other aspects of their ego functioning as well.

Child↗
PubMed1989

Diagnosis of diaphragmatic injury using intraperitoneal technetium.

The diagnosis of diaphragmatic injury following blunt or penetrating trauma is often made after appreciable delay. The purpose of the present study was to evaluate the use of intraperitoneal technetium in diagnosing diaphragmatic tears in dogs. Six dogs were divided into two groups. In Group 1, thoracotomy was performed bilaterally and 1 cm diaphragmatic tears were made. Peritoneal lavage with technetium-99 sulphur colloid was then performed after closure of the thoracotomy sites. In Group 2 animals, only lavage instillation of technetium was done. Scans were then performed and counts recorded over the chest and abdomen. A ratio of two body areas was then computed and compared between the two groups of animals. There was a statistically significant difference in the ratio between the two groups (P less than 0.05). We conclude that intraperitoneal technetium is a sensitive test for diagnosing diaphragmatic injuries.

Animals↗
PubMed1987

Causes of delay in the adequate treatment of childhood illness in India.

A retrospective study of children attending a government hospital in Bangalore was performed to assess the causes of delay in providing appropriate treatment. Delay had occurred in 59% of children with significant illness, and in over half the cases the primary cause of delay was inappropriate treatment or delayed referral by a doctor trained in Western-style medicine. It is concluded that there are a large number of ill children in Bangalore whose parents are seeking the help of such doctors but where management is at fault.

Adolescent↗