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S Morris

Publications and source records attributed to S Morris.

At least 145 records · Page 8Linked to original sources
PubMed1995

Significant hemangiomas and vascular malformations of the head and neck: clinical management and treatment outcomes.

The treatment dilemmas and our institutional experience with head and neck hemangiomas and vascular malformations are reviewed. Fifty-eight patients (38 with hemangiomas, 20 with vascular malformations) aged from newborn to 78 years were treated from 1975 to 1993. Eighty-seven percent of patients provided up-to-date follow-up, yielding a median follow-up interval of 7.18 years from intervention. Only significantly sized tumors (minimum diameter > 4 cm) were studied. Sodium tetradecyl sulfate sclerotherapy (SDS) was a sole therapy in 12 patients (all with hemangiomas) and was used in combination with surgical ablation in 22 patients (16 with hemangiomas, 6 with vascular malformations). The minority of tumors from both categories were completely removed with ablative surgery (six hemangiomas [23%], eight vascular malformations [44%]). Significantly debilitating tumor postsurgical recurrence, which led to mortality in some patients, was unique to vascular malformations with high flow on the basis of increased arterial to venous shunting. Less alarming but significant functional and cosmetic challenges are created in primarily postadolescent patients with incompletely involuted hemangiomas and low-flow vascular malformations of the head and neck. We have had a favorable experience with the combined application of sclerotherapy and conservative ablative surgery in this group. Patient survey implied satisfaction with treatment in the majority: Nine indicated they benefited significantly (17%); 37 indicated they were generally improved (71%); and 6 stated they did not benefit (12%). Tumor-specific philosophy on ablative therapy, recurrence patterns, and associated complications are presented.

Adolescent↗
PubMed1995

Human cytomegalovirus (CMV) DNA in plasma reflects quantity of CMV DNA present in leukocytes.

A quantitative DNA amplification assay for human cytomegalovirus (CMV) DNA has been used to evaluate the relationship between quantities of CMV DNA in plasma and those in infected leukocytes (WBC) from human immunodeficiency virus-infected patients. The target sequence for DNA amplification was a region of the immediate-early 1 gene of CMV. The quantitation assay uses an internal control that is coamplified with each patient sample DNA and contains a sequence for detection by colorimetric hybridization with the same bases, but in different order than in the CMV immediate-early 1 region used for hybridization of amplified patient sample DNA. Results showed that patients with CMV disease had more CMV DNA in both WBC and plasma than those without disease. However, in this study, copy numbers of CMV DNA in WBC were higher than those in plasma. The gB and gH variants were the same in plasma and WBC.

Base Sequence↗
PubMed1995

Hereditary multi-infarct dementia unlinked to chromosome 19q12 in a large Scottish pedigree: evidence of probable locus heterogeneity.

Hereditary multi-infarct dementia is a rare autosomal dominant disorder that predominantly affects the cerebral white matter. A locus was recently mapped in French pedigrees to chromosome 19q12. We have examined a large Scottish pedigree with neuropathologically confirmed hereditary multi-infarct dementia using polymorphic DNA markers spanning the 19q12 region and found no evidence of linkage. This suggests that, as in familial Alzheimer's disease, there is more than one locus.

Adult↗
PubMed1995

TNF modulates endothelial properties by decreasing cAMP.

Tumor necrosis factor-alpha (TNF-alpha), a monokine that contributes to vascular dysfunction accompanying the host response to gram-negative sepsis, has been shown to increase vascular permeability in vivo and to diminish the barrier function of cultured endothelial cell (EC) monolayers. The studies reported here indicate that a mechanism through which TNF alters EC barrier function involves a reduction in intracellular adenosine 3',5'-cyclic monophosphate (cAMP) content, due in part to increased cyclic nucleotide phosphodiesterase (CNPDE) activities. TNF increased the diffusional transit of [3H]sorbitol, [3H]inulin, and 125I-labeled albumin across confluent bovine aortic EC monolayers. This effect of TNF was both time and dose dependent and occurred in parallel with a fall in EC cAMP. cAMP analogues, such as dibutyryl cAMP (DBcAMP), prevented TNF-induced perturbation of EC barrier function. TNF also mediated another important alteration in the EC phenotype, in that both mRNA and activity of the anticoagulant cofactor thrombomodulin were reduced after exposure of EC to TNF and were normalized by the addition of DBcAMP. EC monolayers exposed to TNF-alpha showed increased cAMP levels when exposed to 3-isobutyl-1-methylxanthine, a nonspecific CNPDE inhibitor. Ion exchange chromatography of cytosol derived from TNF-treated EC consistently showed an approximately 245% increase in phosphodiesterase (PDE) IV (high-affinity, cAMP-specific PDE) activity as identified by rolipram inhibition. PDE II activity was increased by 150% after TNF-alpha treatment of early passage EC, which was identified by cGMP-activated hydrolysis of cAMP. Western and Northern analyses, as well as activity studies, revealed that TNF treatment did not change the amount of PDE IV protein or mRNA but rather increased the specific activity of the isozyme, suggesting that a posttranslational modification had occurred. These data indicate that activation of EC CNPDE activity and decreased intracellular cAMP may represent a mechanism by which TNF increases EC permeability and promotes a procoagulant EC phenotype.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1995

Effects of extreme pH on the physiology of the Australian 'yabby' Cherax destructor: acute and chronic changes in haemolymph carbon dioxide, acid-base and ionic status

Freshwater habitats throughout the world are becoming increasingly threatened by the likelihood of acidification, but little consideration has been given to the importance of severe alkalization. Acute and chronic fluctuations in haemolymph acid­base status (PCO2, CCO2 and pH), [Na+] and [Ca2+] were monitored for up to 504 h (21 days) in the Australian freshwater crayfish Cherax destructor exposed to low- and high-pH water. The importance of carapace [Ca2+] during acid exposure was assessed. Crayfish were exposed to pH 7.1, pH 4.5 and pH 8.0 water containing calcium at 500 µmol l-1 while the effect of a lower calcium concentration (50 µmol l-1) was assessed in pH 4.5 water. Cherax in acid water containing 50 µmol l-1 Ca2+ exhibited a significant decrease in CO2 content after 2 h (mean decrease 1.13 mmol l-1, venous; 1.57 mmol l-1, arterial) and large ranges in PCO2 throughout the treatment (2.4­7.3 mmHg). The overall acid­base response was a metabolic acidosis compensated by a respiratory alkalosis. The haemolymph Na+ concentration in both control (pH 7.1, 50 µmol l-1) and acid-exposed animals in lower-Ca2+ water was up to 50 % reduced compared with that in animals in pH 7.1, 500 µmol l-1 Ca2+ water. Ion regulatory mechanisms, causing a subsequent increase in haemolymph [Na+] after 288 h, were implicated as an important component in acid­base homeostasis. Crayfish in acid, low-Ca2+ water also exhibited a 3.2 mmol l-1 increase in haemolymph [Ca2+] and showed a haemolymph alkalosis compared with animals in acid water with higher [Ca2+]. At higher water [Ca2+] in pH 4.5 water (500 µmol l-1 Ca2+), the haemolymph pH of Cherax was only 0.1 unit lower than that of animals in 50 µmol l-1 Ca2+ acid water after 96 h, and both CaCO2 and CvCO2 were unchanged compared with the initial condition. As with low-Ca2+ acid-exposure, the potential haemolymph acidosis appeared largely to be compensated by respiratory alkalosis. There was a transient 31 % reduction in haemolymph [Na+], although osmolality was unchanged (control 411±7.29 mosmol kg-1). Acid­base equilibrium recovered rapidly, probably in association with changes in ion flux and the re-establishment of normal haemolymph Na+ concentration. Alkaline-exposed Cherax destructor exhibited a mixed respiratory alkalosis and metabolic acidosis. Whereas haemolymph [Ca2+] increased by 1.8 mmol l-1 after only 1 h, haemolymph Na+ levels increased by 36 % after 2 h, possibly as part of a net H+ loss from the haemolymph. Increased HCO3-/Cl- exchange could contribute to the 4.3 mmol l-1 decrease in haemolymph CO2 level after 0.5 h of alkaline exposure. The responses of Cherax to extreme pH are different from those of the European and North American crayfish species studied to date.

Journal Article↗
PubMed1995

Effects of extreme pH on the physiology of the Australian 'yabby' Cherax destructor: acute and chronic changes in haemolymph oxygen levels, oxygen consumption and metabolic levels

Respiration and metabolism of the freshwater crayfish Cherax destructor were investigated with respect to the acidification and alkalization of its environment. Crayfish were exposed for up to 504 h (21 days) to pH 4.5, pH 7.1 (control) or pH 8.0 water and oxygen consumption rate, haemolymph oxygen transport and haemolymph glucose and lactate concentrations were determined. The effect of reducing environmental [Ca2+] in acid water from 500 to 50 µmol l-1 was also examined. In acid water (500 µmol l-1 Ca2+), oxygen uptake by Cherax was reduced by 79 % after 504 h (21 days) compared with 'control' animals (pH 7.1, 500 µmol l-1 Ca2+). Haemolymph lactate concentration (mean 0.6 mmol l-1) remained constant, indicating that anaerobiosis was not important, while glucose concentrations were regulated within the range of control values (0.32±0.01 mmol l-1). The arterial-venous CO2 difference of Cherax haemolymph decreased after 288 h and PaO2 increased from 11.1±0.5 mmHg to 42.4±1.0 mmHg between 96 h and 288 h. Decreased oxygen uptake and delivery without compensatory increases in anaerobiosis or glucose levels describe a hypometabolic response to low pH. The hypometabolic response of Cherax was greater in alkaline water as shown by a 53 % reduction in O2 uptake rate compared with a 44 % reduction in acid-exposed (500 µmol l-1 Ca2+) animals after 96 h. This decrease in M(dot)O2 of alkaline-exposed animals was correlated with decreased haemolymph glucose levels (from 0.32±0.01 at 0 h to 0.06±0.01 mmol l-1 at 96 h). Lowering the [Ca2+] of the water both increased the magnitude of the effects of acid exposure and elicited further changes in haemolymph oxygen transport. The maintenance of high haemolymph PO2 during pH stress appears to reduce the involvement of haemocyanin, since this promotes decreased a­v CO2. Hypometabolism probably permits Cherax to conserve resources that might otherwise be used, however, for growth and reproduction. The implications for the fitness of the animal are discussed.

Journal Article↗
PubMed1995

Bovine tuberculosis survey in the Molopo district of the North West Province.

A survey was conducted in the Molopo district of the North West Province to determine the prevalence of bovine tuberculosis in the cattle population of 57,000 grazing on communal and privately owned lands. Testing of cattle (n = 9,675) for tuberculosis was done by means of the comparative intradermal tuberculin test. The prevalence was found to be 0.062%. The significance of this result, when compared to the reported incidence of tuberculosis within the human population of the district, is discussed.

Animals↗
PubMed1995

Positive ageing.

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Adaptation, Psychological↗
PubMed1995

Care in action.

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Female↗
PubMed1994

The laryngeal mask airway: its features, effects and role.

The laryngeal mask airway was designed as a new concept in airway management and has been gaining a firm position in anaesthetic practice. Numerous articles and letters about the device have been published in the last decade, but few large controlled trials have been performed. Despite widespread use, the definitive role of the laryngeal mask has yet to be established. In some situations, such as after failed tracheal intubation or in anaesthesia for patients undergoing laparoscopic or oral surgery, its use is controversial. There are a number of unresolved issues, for example the effect of the laryngeal mask on regurgitation and whether or not cricoid pressure prevents placement of the mask. We review the techniques of insertion, details of misplacement, and complications associated with the use of the laryngeal mask. We discuss the features and physiological effects of the device, including the changes in intra-cuff pressure during anaesthesia and effects on blood pressure, heart rate and intra-ocular pressure. We then attempt to clarify the role of the laryngeal mask in airway management during anaesthesia, based on the current knowledge, by discussing the advantages and disadvantages as well as the indications and contraindications of its use. Lastly we describe the use of the laryngeal mask in circumstances other than airway maintenance during anaesthesia: fibreoptic bronchoscopy, tracheal intubation through the mask and its use in cardiopulmonary resuscitation.

Anesthesia↗
PubMed1994

Effect of ilioinguinal and iliohypogastric nerve block and wound infiltration with 0.5% bupivacaine on postoperative pain after hernia repair.

We have compared, in 40 adult males, the effect on pain in the first 24 h after herniorrhaphy of preincisional ilioinguinal and iliohypogastric nerve block and wound infiltration with 0.5% bupivacaine or saline. After operation, patients received morphine i.v. via a patient-controlled analgesia machine and visual analogue pain scores (VAS) at rest and on movement were recorded. The bupivacaine group consumed less morphine in the first 6 h after operation. There was no difference in morphine consumption between the two groups in the next 18 h. The time to first analgesia was delayed in the bupivacaine group and was not followed by a rebound increase in requirement for analgesia. There was no significant difference in VAS scores at rest but there was a significantly higher pain score with movement in the saline group. We have shown that the combination of nerve block and wound infiltration reduces consumption of morphine in the first 24 h after herniorrhaphy. We have failed to show any effect of 0.5% bupivacaine beyond the first 6 h after operation.

Adult↗
PubMed1994

Deficiency in antibody response to human cytomegalovirus glycoprotein gH in human immunodeficiency virus-infected patients at risk for cytomegalovirus retinitis.

Human immunodeficiency virus (HIV)-infected patients at risk for symptomatic human cytomegalovirus (CMV) infection were studied for serum antibody to CMV glycoproteins gH and gB. Antibody titers to gB in HIV-seropositive patients, irrespective of CD4 cell counts or presence of CMV retinitis, were significantly higher than titers in HIV-seronegative, CMV-seropositive patients but were comparable to titers detected in HIV-seronegative patients with CMV mononucleosis. In contrast, antibody to gH was rarely detected in HIV-seropositive patients with CD4 cell counts > 100/mm3 compared with patients with counts > 100/mm3. The inability to detect gH antibody at a time of high risk for symptomatic CMV retinitis suggests that immune intervention with either gH-specific vaccine or passive immunotherapy may benefit HIV-infected persons at risk for symptomatic CMV disease.

AIDS-Related Opportunistic Infections↗
PubMed1994

The through-and-through oromandibular defect: rationale for aggressive reconstruction.

Through-and-through oral cancer (T4+) involving contiguous mucosa, mandible, and skin is a devastating disease with poor prognosis and represents one of the most difficult reconstructive challenges in head and neck surgery. Thirty-eight patients underwent immediate microvascular reconstruction following surgical tumor ablation. The purpose of the present review was to assess the value of microvascular reconstruction in these essentially palliative reconstructive efforts. The iliac crest osteocutaneous flap was used in the majority of patients and was found to be ideal for the reconstruction of large bony and soft-tissue defects present in this group of patients. Other methods, including pectoralis major, forehead, and latissimus dorsi flaps, also were used in the soft-tissue reconstruction. The mean follow-up was 16 +/- 2 months, and the mean hospitalization was 43 +/- 22 days. The majority of patients succumbed to recurrent or related diseases, yet a few went on to survival despite the initial advanced stage of disease. A number of complications were observed. However, most patients developed normal or easily intelligible speech (65 percent), and most (78 percent) had their tracheostomies closed and sustained themselves on an oral soft diet (84 percent). Bony union was noted in the majority of patients (73 percent). Although the prognosis in full-thickness oral carcinoma is grim, it appears that palliative surgery in these cases is well justified. The goals are to shorten the duration of hospitalization, reduce morbidity, and improve the remaining quality of life. Microvascular tissue transfer offers a means to achieve these goals in a single, reliable procedure. We feel that immediate one-stage bone and soft-tissue reconstruction restores dignity and relieves suffering in this unfortunate group of individuals.

Adult↗
PubMed1994

Screening schizophrenic patients for mutations in the amyloid precursor protein gene.

A limited number of rare missense mutations in exons 16 and 17 of the amyloid precursor protein (APP) gene have been reported. They are associated with a variety of phenotypes including cerebral haemorrhage, multi-infarct dementia and Alzheimer's disease. We recently reported an alanine to valine mutation in codon 713 in a single case of chronic familial schizophrenia with cognitive deficits. Using denaturing gradient gel electrophoresis (DGGE) we have screened a cohort of 250 chronic schizophrenics for further mutations of exons 7, 16 and 17. None were found. Nevertheless recent evidence suggests that the 713 mutation is indeed pathogenic for the clinical phenotype observed; the mechanisms involved are outlined.

Amyloid beta-Protein Precursor↗