PubMed Health⌕ Search

Biomedical subjects

M Tomlinson

Publications and source records attributed to M Tomlinson.

At least 19 recordsLinked to original sources
PubMed2006

Post-partum depression and infant growth in a South African peri-urban settlement.

AIM: To examine the association between maternal post-natal depression and infant growth. BACKGROUND: Infant growth has recently been shown, in two studies from South Asia, to be adversely affected by maternal depression in the early post-partum period. It is uncertain whether a similar association obtains in developing countries outside Asia. METHOD: A sample of 147 mother-infant dyads was recruited from a peri-urban settlement outside Cape Town and seen at 2 and 18 months post partum. RESULTS: No clear effect of post-partum depression on infant growth was found. Although maternal depression at 2 months was found to be associated with lower infant weight at 18 months, when birthweight was considered this effect disappeared. CONCLUSIONS: Possible explanations for the non-replication of the South Asian findings are considered.

Adult↗
PubMed2005

Endocarditis and ulnar artery aneurysm as presenting features of antiphospholipid syndrome and polyarteritis nodosa.

Antiphospholipid syndrome in association with vasculitis is highlighted in this report. The combination of thrombotic and inflammatory processes resulted in endocarditis, aneurysm formation and thrombosis. To our knowledge this is the first presentation of a large vessel aneurysm in these conditions. Anticoagulation and immunosuppression are the treatment modalities of choice.

Aneurysm↗
PubMed2004

Reduced senescence and retained nuclear DNA integrity in human spermatozoa prepared by density gradient centrifugation.

PURPOSE: To investigate whether removal of extraneous cells and immotile spermatozoa from a sperm preparation by density gradient centrifugation could help to maintain normal spermatozoa in a viable state and retain their deoxyribonucleic acid integrity. METHODS: Sperm motility was assessed on a daily basis in aliquots of neat semen, extended semen, and spermatozoa prepared on a PureSperm density gradient. At the same time, aliquots of each sperm sample were preserved for TUNEL assay and nick translation. RESULTS: Spermatozoa prepared using density gradient centrifugation survived three times as long as spermatozoa in neat semen or in extended semen. Both deoxyribonucleic acid integrity and sperm motility were retained in the gradient preparations. CONCLUSIONS: Preparing spermatozoa by density gradient centrifugation is advantageous in prolonging sperm survival and maintaining deoxyribonucleic acid integrity, presumably by removing sources of reactive oxygen species. Stored spermatozoa could be used for a second attempt at fertilization if oocyte immaturity was suspected.

Adult↗
PubMed2002

Aminolaevulinic acid-induced photodynamic therapy: cellular responses to glucose starvation.

Photodynamic therapy is a cancer treatment based on the interaction of light, oxygen and a photosensitiser. Protoporphyrin. IX is an endogenous photosensitiser derived from the pro-drug aminolaevulinic acid. Tumours contain areas of hypoxia and hypoglycaemia. Tumour cells adapt to these conditions by stress protein induction which may induce resistance to cancer therapies. The effect of chronic hypoglycaemia on sensitivity to aminolaevulinic acid-induced photodynamic therapy in vitro was studied in MCF-7, human breast cancer cells. Following chronic exposure to 0, 1 or 25 mM, glucose, cells were treated with aminolaevulinic acid and the generation of intracellular protoporphyrin. IX measured by spectrofluorimetry. Aminolaevulinic acid-induced photodynamic therapy sensitivity was compared between cells following chronic exposure to 0, 1 or 25 mM glucose. Percentage cell survival was determined by clonogenic assay. Cells cultured in low glucose generated higher levels of protoporphyrin IX compared to standard glucose medium (0 mM glucose: 0.88 x 10(-5) ng cell(-1), 1 mM: 0.86 x 10(-5) ng cell(-1), 25 mM: 0.60 5x 10(-5) ng cell(-1), P<0.05). However, photodynamic therapy sensitivity was reduced in glucose deprived cells (0 mM glucose: 61% survival, 1 mM: 80.5% and 25 mM: 39.6%, P<0.05). Chronic exposure to low glucose induces photodynamic therapy resistance despite increased intracellular concentrations of protoporphyrin IX and may reflect cellular adaptation to chronic glucose deprivation.

Aminolevulinic Acid↗
PubMed2002

Severe pre-eclampsia remote from term: what to expect of expectant management.

OBJECTIVE: To describe the duration of expectant management and the indications for termination of expectant management of pregnancies complicated by severe pre-eclampsia remote from term. STUDY DESIGN: We identified pregnancies complicated by severe pre-eclampsia diagnosed between 24 weeks and 31 weeks 6 days at our institution in 1991-98. Pertinent clinical data were obtained from review of maternal and neonatal charts. Comparison of patients was based on the duration of time from admission to delivery: < 48 h (group 1), 48 h to 7 days (group 2), and > or = 7 days (group 3). RESULTS: A total of 142 women met all study criteria. Seventy-nine (55.6%) women were delivered within 48 h, 42 (29.6%) between 48 h and 7 days, and 21 (14.8%) at > or = 7 days from diagnosis. Of group 1 patients (< 48 h), 59 (74.7%) were delivered for maternal indications while 20 (25.3%) were delivered for fetal indications. Of group 2 patients (48 h to 7 days), 35 (83.3%) were delivered for maternal indications while seven (16.7%) were delivered for fetal indications. Of group 3 patients (> or = 7 days), 16 (76.2%) were delivered for maternal indications while five (23.8%) were delivered for fetal indications. There were no significant differences in the indications for delivery based on the duration from admission to delivery. CONCLUSIONS: Despite an aggressive approach towards expectant management of preterm pregnancies complicated by severe pre-eclampsia, most patients were delivered within 48 h for maternal indications.

Adult↗
PubMed2001

Does cervical cerclage prevent preterm delivery in patients with a short cervix?

OBJECTIVE: Our purpose was to determine whether cerclage placement in women with a short cervix on transvaginal ultrasonography reduces the rate of preterm delivery. STUDY DESIGN: A retrospective cohort study identified patients with an ultrasonographic short cervix (cervical length < or =15 mm) between 14 and 24 weeks' gestation. Cerclage placement was performed at the discretion of the attending physician. Clinical characteristics and outcome with and without cerclage were compared. RESULTS: Seventy patients met inclusion criteria; 25 (36%) underwent cerclage placement. Patients managed with cerclage had a lower gestational age at diagnosis (19.6 weeks vs 21.3 weeks, P <.01) but had a similar median cervical length, presence of funneling, and a history of cervical surgery, in comparison with those managed without cerclage. The rate of spontaneous preterm delivery was not different between groups. Patients with cerclage had a higher rate of preterm premature rupture of membranes than those without cerclage (65.2% vs 36.4%, P <.05). CONCLUSION: Cervical cerclage in patients with a short cervix did not reduce the rate of spontaneous preterm delivery and increased the risk of preterm premature rupture of membranes.

Adolescent↗
PubMed2001

Labor induction for the preterm severe pre-eclamptic patient: is it worth the effort?

OBJECTIVE: The purpose of this study was to examine the success rate of labor induction in patients with severe pre-eclampsia delivered at < or = 34 weeks' gestation; to identify factors associated with its success; and to evaluate neonatal outcomes based on induction success or failure. METHODS: We identified pregnancies complicated by severe pre-eclampsia delivered at < or = 34 weeks' at our institution from 1991 to 1998. Women who underwent labor induction and had successful vaginal delivery were compared to those who underwent labor induction, but required Cesarean delivery. Multiple logistic regression analyses were performed to assess factors associated with successful induction and neonatal outcome. RESULTS: Over the 7-year study period, there were 215 patients meeting the criteria. Sixty-four (29.8%) did not undergo a labor attempt; 69 of 151 (46%) women who underwent labor induction achieved vaginal delivery. Labor induction was successful in 0%, 6.6%, 35.3% and 68.5% of cases at 24-26, 27-28, 29-31 and 32-34 weeks' gestation, respectively. By logistic regression the only factor positively associated with successful induction was gestational age at delivery (p = 0.001), while induction for non-reassuring fetal testing was inversely associated (p = 0.02). Induction attempt, failed induction and delivery mode were not associated with increased neonatal morbidity. CONCLUSIONS: In women with severe pre-eclampsia remote from term, attempted labor induction did not appear to increase neonatal morbidity, but was rarely successful at < 28 weeks.

Adult↗
PubMed2001

One-step disposable chambers for sperm concentration and motility assessment: how do they compare with the World Health Organization's recommended methods?

The World Health Organization suggests that 'one-step' type disposable chambers lack the accuracy and precision of the haemocytometer method for assessing sperm concentration. The purpose of this particular study was to compare sperm concentration measurements and motility using the Neubauer((R)) haemocytometer with those obtained using three 'one-step' methods: the Microcell((R)) slide, Leja((R)) slide and a plain glass slide with a 22x22 mm coverslip. A total of 200 sperm concentration measurements and 100 motility assessments were performed on all chambers. Paired comparisons showed enormous discrepancies between the counts, particularly between the Neubauer((R)) and other chambers (P < 0.0001). This discrepancy was less pronounced in oligozoospermic samples, and samples with low (<30% progression) motility but more pronounced in normozoospermic samples and those with good motility (>50% progression). In addition, concentration assessments from a fresh undiluted and unfixed semen sample on the Microcell((R)) slide were found to be significantly lower than both fixed counts on the same slide (P = 0.011) and the initial laboratory reading on the Neubauer((R)) chamber (P = 0.009). No differences were observed in progressive motility between the different chambers and a plain glass slide. There appears to be little comparison between the haemocytometer and either re-useable or disposable one-step chambers. The unfortunate consequence of this is that diagnostic semen analysis and guidelines for allocation of patients to appropriate treatment groups will vary from centre to centre, depending on the method used and may, on occasion, be erroneous.

Humans↗
PubMed2001

Paradoxical embolus: an unusual indication for upper limb amputation.

Paradoxical emboli occur when venous embolic material passes into the arterial circulation (via a right-to-left cardiac shunt). The association of paradoxical emboli and arterial ischaemia has been described previously, especially with respect to cerebral infarcts. We describe a case in which double paradoxical emboli following a long haul flight, resulted in emergency amputation of an upper limb. Amputation resulting from a paradoxical embolus has not previously been described.

Aerospace Medicine↗
PubMed2000

Assessment of sperm competence.

The predictive values of four categories of established sperm function assays--computer-assisted semen analysis (CASA), induced-acrosome reaction testing, sperm penetration assay, and sperm-zona pellucida binding assays--are still unsure. In this article we examine the evaluation of sperm competence. We propose that assessment of sperm competence should include investigations at the nuclear, organelle, and cytoskeletal levels. In light of this, we discuss the assessment of sperm nuclear integrity as an alternative new method of analysis. We also question the merit of having such tests, whereby it may be an easier choice to direct these patients straight to an assisted reproduction treatment.

Acrosome Reaction↗
PubMed2000

Is a review of standard procedures for cryopreservation needed?: safe and effective cryopreservation-should sperm banks and fertility centres move toward storage in nitrogen vapour?

A recent consultation documentation by the Human Fertilisation and Embryology Authority (HFEA) which focused on the safe cryopreservation of gametes and embryos highlighted the need for a review of the way that fertility clinics in the UK store potentially infective material. The main points for consideration were to: (i) ensure containers used for cryopreservation are guaranteed by manufacturers to withstand low temperatures; (ii) use secondary containers, i.e. 'double bagging' of samples if stored in the liquid phase; and (iii) store in nitrogen vapour as a 'safer' alternative. In this article we examine a number of issues related to vapour storage which need careful consideration, including safety, cost and the effectiveness of various storage techniques in maintaining gamete and embryo viability. We also discuss the effectiveness of vapour storage in comparison with current liquid nitrogen storage techniques. In conclusion, we propose that fertility clinics should be compelled to review their cryopreservation procedures, not just because of new legislation or indeed fear of litigation but by a moral obligation.

Bacterial Infections↗
PubMed2000

The use of two density gradient centrifugation techniques and the swim-up method to separate spermatozoa with chromatin and nuclear DNA anomalies.

Human semen is heterogeneous in quality, not only between males but also within a single ejaculate. Differences in quality are evident, both when examining the classical parameters of sperm number, motility and morphology and in the integrity of the sperm nucleus. The aim of this study was to determine the efficiency of the PureSperm((R)), Percoll((R)) and swim-up preparation techniques to eliminate spermatozoa with nuclear anomalies. Semen samples were collected, washed and one part of the semen spread on a slide, the remainder was prepared using the swim-up, PureSperm((R)) or Percoll((R)) techniques. Spermatozoa from different fractions were fixed on slides and assessed. Sperm samples (n) from different men were stained using the chromomycin A(3) (CMA(3)) fluorochrome, which indirectly demonstrates a decreased presence of protamine (n = 31 for swim-up; n = 45 for PureSperm((R)); n = 39 for Percoll((R))). Spermatozoa prepared using PureSperm((R)) (n = 35) and Percoll((R)) (n = 37) were also examined for the presence of endogenous DNA nicks. Good quality spermatozoa should not possess DNA nicks and not stain (i.e. fluoresce) with CMA(3). When prepared using the swim-up technique the spermatozoa recovered showed no significant improvement with the CMA(3) staining. When spermatozoa were prepared using the PureSperm((R)) and Percoll((R)) techniques, a significant (P < 0.001) decrease in both CMA(3) positivity and DNA strand breakage was observed. These results indicate that both the PureSperm((R)) and Percoll((R)) techniques can enrich the sperm population by separating out those with nicked DNA and with poorly condensed chromatin.

Centrifugation, Density Gradient↗
PubMed1999

Risk factors for ankle fracture requiring operative fixation.

BACKGROUND: Ankle fractures are common and expensive injuries, particularly the injuries that require operative intervention. However, epidemiological research on the causative factors is sparse. This study aims to identify the groups at risk of ankle fracture requiring operative fixation, and to suggest directions for further study. METHODS: The clinical data on 336 patients with ankle fractures admitted to an urban hospital in New Zealand in 1994 were reviewed. Statistical analysis was carried out on the 252 patients with ankle fractures requiring operative fixation. RESULTS: Those at highest risk of ankle fracture are young male rugby players and middle-aged women who sustain injury while walking. Young males have a similar incidence of AO Type B and C fractures, while Type B fractures predominate strongly in older women. CONCLUSIONS: The groups at risk of ankle fracture requiring operative fixation, and the activities predisposing these groups to injury have been identified. More work is required to define the specific risk factors and biomechanical mechanisms that lead to these debilitating injuries.

Adolescent↗
PubMed1999

Post-partum depression and the mother-infant relationship in a South African peri-urban settlement.

BACKGROUND: Post-partum depression in the developing world has received little research attention, and its association with disturbances in the mother-infant relationship is unknown. AIMS: To determine the prevalence of post-partum depression and associated disturbances in the mother-infant relationship in Khayelitsha, a South African peri-urban settlement. METHOD: The mental state of 147 women who had delivered two months previously was assessed, and the quality of their engagement with their infants was determined. RESULTS: The point prevalence of DSM-IV major depression was found to be 34.7%. Maternal depression was associated with poor emotional and practical support from the partner. It was also associated with insensitive engagement with the infants. CONCLUSIONS: The rate of post-partum depression in Khayelitsha was around three times that found in British post-partum samples, and these depressions were strongly associated with disturbances in the mother-infant relationship.

Adult↗
PubMed1997

Combined radiotherapy and medical immunosuppression in the management of thyroid eye disease.

Although systemic steroids or orbital radiotherapy are effective in limiting the inflammatory response in thyroid eye disease (TED), there are reports of over 70% of treated patients requiring subsequent rehabilitative surgery: either orbital decompression or strabismus correction. This study investigated whether combined immunosuppression with primary orbital radiotherapy together with azathioprine and low-dose prednisolone, applied early in the active disease state, was more effective in treating TED. Forty consecutive patients with active TED were recruited. Orbital MRI (STIR sequence) was used to assess disease activity. Median duration of symptoms was 1.0 year. Subjects were treated with bilateral orbital radiotherapy (20 Gy in 10 fractions) and oral prednisolone and azathioprine. Pre- and post-treatment activity was measured clinically, including uniocular field of fixation, Mourits score and total eye score, until TED became inactive off all treatment. Before treatment, 15 subjects had signs of dysthyroid optic neuropathy, 35 had significant motility restriction and 38 had marked soft tissue signs. On average TED became inactive after 1.2 years (SD 0.7) of immunosuppression, and treatment was well tolerated. One patient required subsequent cosmetic orbital decompression, 6 had successful strabismus surgery and 13 required minor cosmetic lid surgery. Compared with previously reported treatment regimes we think that combined orbital radiotherapy and medical immunosuppression is far more effective than either treatment alone in the management of active TED, and led to fewer side effects of high-dose steroids. In particular there was more than a four-fold reduction in the requirement for orbital decompression and strabismus surgery.

Adult↗