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Biomedical subjects

P J Moore

Publications and source records attributed to P J Moore.

At least 19 recordsLinked to original sources
PubMed2005

Sperm competition and male ejaculate investment in Nauphoeta cinerea: effects of social environment during development.

Selective pressure arising from sperm competition has been predicted to influence evolutionary and behavioural adjustment of ejaculate investment, but also may influence developmental adjustment of ejaculate investment. Immature males able to target resources strategically based on the competitive environment they will experience when they become sexually mature should be at a selective advantage. In our study we investigated how the presence of potential competitors or mates affects ejaculate and testes investment during development in the cockroach Nauphoeta cinerea, a species where males control female remating via their ejaculate size (large spermatophores prevent females from remating and therefore function to avoid sperm competition for males) and females store sperm. Our aim was to determine whether the social environment influences developmental adjustment of ejaculate investment and the relative importance of ejaculate components with different functions; avoidance of or engagement in sperm competition. We conclude that the social environment can influence developmental and behavioural flexibility in specific ejaculate components that may function to avoid or engage in sperm competition.

Analysis of Variance↗
PubMed2005

Comparison of rigid vs flexible sigmoidoscopy in detection of significant anorectal lesions.

OBJECTIVE: Sigmoidoscopy is an essential tool in colorectal clinics in the detection of anorectal lesions including rectosigmoid adenomas and carcinomas. However, rigid sigmoidoscope (RS) is still more widely used than flexible sigmoidoscope (FS) as the primary investigation, despite the fact that the latter is more comfortable to the patient and has greater diagnostic yield. Hence we wanted to compare the two modalities in terms of diagnostic use for picking up significant anorectal lesions. METHODS: A retrospective review of all patients referred to the colorectal clinic who had undergone both rigid and flexible sigmoidoscopy for investigation of colorectal symptoms in 2001 was done. Findings recorded during rigid and flexible sigmoidoscopy including depth of insertion, site of lesion and complications were analysed. RESULTS: 152 patients underwent both rigid and flexible sigmoidoscopy as part of investigation of colorectal symptoms. Of the 115 (75.6%) declared normal by RS, 39 (33.9%) had significant lesions including 7 polyps and 4 malignant lesions within 20 cm of the anal verge during FS. Of the 31 patients (20.4%) in whom RS was not helpful due to faecal loading, 15 (48.4%) had significant lesions including 4 malignancies and 1 polyp --all within 20 cm of the anal verge during FS. Only 2 polyps and 1 malignant lesion were picked up by both flexible and rigid sigmoidoscopy. There were no complications in both procedures. CONCLUSION: Since flexible sigmoidoscopy is superior to rigid sigmoidoscopy in terms of patient comfort, diagnostic value and ease of doing procedures like biopsy and polypectomy; it can be used as a front line investigation to exclude colorectal pathology in out patient clinics. The utility of rigid sigmoidoscope is in question and in view of obvious shortcomings, may be replaced by flexible sigmoidoscopy, though obvious resource constraints need to be considered.

Humans↗
PubMed2005

Endoscopic laser ablation of advanced rectal carcinoma--a DGH experience.

BACKGROUND: Patients with inoperable advanced rectal carcinoma require palliation for local symptoms. Endoscopic Nd-Yag laser ablation is a valid palliative treatment option in patients with advanced rectal carcinoma who are poor operative risks due to coexistent multiple comorbidities. METHODS: All patients who cannot undergo radical surgery due to various factors such as tumour size, poor risk patients, distant metastasis and refusal to undergo surgery were offered palliation with endoscopic Nd-YAG laser ablation. Indications included troublesome bleeding, local recurrence, mucous discharge and impending obstruction. Patients were admitted on the day of treatment, phosphate enema given for bowel preparation and endoscopic ablation done through a flexible sigmoidoscope under intravenous sedation with midazolam. All patients were discharged the next day after overnight observation. Patients were reviewed every 3 months and laser ablation repeated if deemed necessary. RESULTS: Eleven patients (7 males, 4 females; mean age 83.6 years, range 77-90 years) underwent endoscopic laser ablation in a District General Hospital --8 for rectal carcinoma, 2 for rectosigmoid tumour and 1 for recurrent tubulovillous adenoma. The number of treatment episodes varied from 1 to 12 with symptom free interval from 2 to 18 months between treatment episodes. There were 3 failures, one patient required defunctioning colostomy, one patient was referred for radiotherapy due to persistent symptoms and in one patient laser treatment had to be abandoned due to local extent. There were no immediate post-treatment complications, but one patient developed incontinence after 5 episodes which might be attributable to tumour infiltration. DISCUSSION: Endoscopic laser ablation is a practical and feasible alternative to other palliative treatment modalities in the management of this unfortunate category of patients due to low morbidity and mortality, short hospitalization and low complication rates.

Adenoma, Villous↗
PubMed2004

Sexual conflict and cooperation under naturally occurring male enforced monogamy.

An evolutionary conflict often exists between the sexes in regard to female mating patterns. Females can benefit from polyandry, whereas males mating with polyandrous females lose reproductive opportunities because of sperm competition. Where this conflict occurs, the evolution of mechanisms whereby males can control female remating, often at a fitness cost to the female, are expected to evolve. The fitness cost to the female will be increased in systems where a few high status males monopolise mating opportunities and thus have limited sperm supplies. Here we show that in the cockroach Nauphoeta cinerea, a species where males enforce female monogamy in the first reproductive cycle, males that have become sperm depleted continue to be able to manipulate female remating behaviour. Although the manipulation severely decreases fecundity in females mated to sperm-depleted males, males benefit, increasing their relative fitness by preventing other males from reproducing. Our results suggest that there is selection on maintaining the mechanism of manipulation rather than maintaining sperm numbers. Taken with previous research on sexual conflict in N. cinerea, this study suggests that the causes and consequences of sexual conflict are complex and can change across the life history of an individual.

Analysis of Variance↗
PubMed2003

Females avoid manipulative males and live longer.

Female mate choice has been demonstrated in a wide variety of species and is now accepted as an important factor in sexual selection. One of the remaining questions, however, is why females prefer specific males. Do females or their offspring benefit from their choice? Or do females choose mates to minimize costs of mating? Here we show that, in the ovoviviparous cockroach Nauphoeta cinerea, where sexual selection has been well documented, females chose mates to avoid costly male manipulation. Females were partnered with preferred or nonpreferred mates, and fitness of the females measured. We found that females lived longer when they mated with preferred males. Female lifespan depended on the rate at which offspring developed from egg to parturition: slower development led to longer life. We manipulated the male pheromone and showed that the component of the pheromone blend that makes males attractive to females also delayed parturition. Thus, like other aspects of sexual conflict in this species, offspring development and thereby the mother's lifespan depended on exposure of females to specific components of the male pheromone. Males benefit from manipulating offspring development because females with accelerated parturition remained unreceptive whereas females with slower developing offspring readily remated after giving birth to their offspring. Our results suggest a hormone-like role for the male pheromone in N. cinerea and provide the first direct evidence of mate choice to avoid male manipulation. This study shows that dominant males may not be preferred males if they are manipulating females, why multiple components with contrasting effects can exist in a sexual signal, and emphasizes the complex fitness relationships that can arise in species with sexual conflict.

Animals↗
PubMed2001

Clinical value of postnatal autopsy and genetics consultation in fetal death.

The aim of the present study was to investigate the clinical use of postnatal autopsy and genetics consultation in cases of fetal death in a teaching hospital. A retrospective analysis of medical records including pathology and genetics reports was performed in all cases of fetal death in which a woman delivered at Ben Taub General Hospital, Houston, Texas over a 2-year period. Cases were excluded when gestational age of the fetus was less than 20 weeks. Fetuses were only included when the 1- and 5-min Apgar scores were 0 and 0, respectively. There were 139 fetal deaths and 12,209 live born infants during the study period (stillbirth rate 1.125%). Although pathology services were used in 96.2%, a genetics consultation was obtained in only 12% of cases. Fetal autopsy provided a certain cause of fetal death in 19.4%, a probable cause for death in 36.3%, and was inconclusive in 44.3%. Among the cases in which a genetics consultation was obtained, a certain and probable cause for fetal death was found in 20% and 20% of cases, respectively. The utilization of genetics consultation was found to be independent of multiple clinical variables examined including ultrasound data, identification of maceration, and training level of resident. Our data show a frequent use of pathologic examination in cases of fetal death and an infrequent use of genetics consultation services. The request for genetics consultation seemed to have been made at random.

Autopsy↗
PubMed2001

Reproductive aging and mating: the ticking of the biological clock in female cockroaches.

Females are expected to have different mating preferences because of the variation in costs and benefits of mate choice both between females and within individual females over a lifetime. Workers have begun to look for, and find, the expected variation among females in expressed mating preferences. However, variation within females caused by changes in intrinsic influences has not been examined in detail. Here we show that reproductive aging caused by delayed mating resulted in reduced choosiness by female Nauphoeta cinerea, a cockroach that has reproductive cycles and gives live birth. Male willingness to mate was unaffected by variation in female age. Females who were beyond the optimal mating age, 6 days postadult molt, required considerably less courtship than their younger counterparts. Females who were older when they mated had fewer offspring per clutch and fewer clutches than females who mated young. Thus, reduced choosiness was correlated with a permanent reduction in fertility. There was no difference in overall senescence among females, and thus the reduction in clutch size did not result in the expected increased lifespan. We suggest that reproductive aging in N. cinerea, similar to aging in general, occurs because the maintenance of oocytes is costly, and selection is relaxed after the optimal mating period. Our results further suggest that selection for continued choosiness is also relaxed and supports direct selection on female choosiness and a cost to choosiness.

Aging↗
PubMed2001

Sexual conflict and the evolution of female mate choice and male social dominance.

Conflicts between the sexes over control of reproduction are thought to lead to a cost of sexual selection through the evolution of male traits that manipulate female reproductive physiology and behaviour, and female traits that resist this manipulation. Although studies have begun to document negative fitness effects of sexual conflict, studies showing the expected association between sexual conflict and the specific behavioural mechanisms of sexual selection are lacking. Here we experimentally manipulated the opportunity for sexual conflict in the cockroach. Nauphoeta cinerea and showed that, for this species, odour cues in the social environment influence the behavioural strategies and fitness of males and females during sexual selection. Females provided with the opportunity for discriminating between males but not necessarily mating with preferred males produced fewer male offspring than females mated at random. The number of female offspring produced was not affected, nor was the viability of the offspring. Experimental modification of the composition of the males' pheromone showed that the fecundity effects were caused by exposure to the pheromone component that makes males attractive to females but also makes males less likely to be dominant. Female mate choice therefore carries a demographic cost but functions to avoid male manipulation and aggression. Male-male competition appears to function to circumvent mate choice rather than directly manipulating females, as the mate choice can be cryptic. The dynamic struggle between the sexes for control of mating opportunities and outcomes in N. cinerea therefore reveals a unique role for sexual conflict in the evolution of the behavioural components of sexual selection.

Animals↗
PubMed2001

The relationship between fatigue and sleep in cancer patients: a review.

Fatigue is a major complaint among cancer patients, yet it is unknown whether cancer-related fatigue experienced during the day relates to sleep/wake cycles or to the quality and quantity of sleep obtained at night. Although it is not well defined or well understood at present, cancer-related fatigue is generally regarded as a form of tiredness that does not improve following rest or sleep. Objectively recorded sleep and biological rhythms have not been well investigated in these patients, but it appears that most cancer patients may in fact not be getting a good night's sleep. Evidence is accumulating that sleep is often disturbed in cancer patients, probably owing to a variety of causes. We posit that some degree of cancer-related fatigue experienced during the day may relate to sleep/wake cycles or to the quality and quantity of sleep obtained at night. Different components or dimensions of fatigue (physical, attentional/cognitive, emotional/affective, etc.) are probably associated in some way with disrupted sleep and desynchronized sleep/wake rhythms. These associations may change in measurable ways prior to treatment, during treatment and after treatment completion. In cancer patients, as in other medically ill patients, sleep that is inadequate or unrefreshing may be important not only to the expression of fatigue, but to the patients' quality of life and their tolerance to treatment, and may influence the development of mood disorders and clinical depression. This review summarizes the state of the literature on fatigue, sleep and circadian rhythms.

Circadian Rhythm↗
PubMed2000

The role of photodynamic therapy (PDT) in inoperable oesophageal cancer.

OBJECTIVE: To evaluate the role of PDT in palliation of patients with inoperable oesophageal cancer and to identify subgroups in which this role is of particular significance. METHODS: Sixty-five patients (37 male, 28 female) aged 42-89 (mean 65.6) with advanced and inoperable oesophageal cancer were the subjects of this study. Inoperability was due to advanced stage of the disease in 61 and because of general condition in 4. Fifty-eight (89%) had previous treatments, other than PDT. All patients had dysphagia of whom 20 could not swallow fluid. Pre-PDT clinical, radiological and endoscopic examinations were carried out. Performance status (PS) and clinical staging was assessed. PDT protocol consisted of: intravenous injection of 2 mg/kg; photofrin (or equivalent polyhaematoporphyrin) followed 24-72 h later by endoscopic illumination using 630 nm laser light. MAIN OUTCOME MEASUREMENTS: (1) Relief of dysphagia generally and specifically in those with cervical and post-cricoid carcinoma who were previously treated by external beam radiotherapy (EBR) (n=6) and those with previous intubation or stent (n=9); (2) Survival. RESULTS: There was no PDT related mortality. Three patients (4.6%) developed a mild skin photosensitivity reaction. Dysphagia was relieved in all patients. The mean and median survival of the 58 patients who have died was 7. 7 and 6 months respectively. Seven patients are alive from 2-30 months (mean 16). Survival was not significantly influenced by tumour histology, location in the oesophagus, severity of dysphagia on admission, or by previous therapy. Survival was significantly influenced by Performance Status prior to treatment (P=0.03 log rank, for PS < or =2 vs. PS=3), an most significantly by the stage of the disease (P=0.0001 log rank, for Stage III vs. Stage IV). CONCLUSIONS: (1) PDT is safe and effective for palliation of dysphagia in inoperable oesophageal cancer. This is particularly important in post-cricoid and cervical oesophageal cancer previously treated by other methods and for patients with recurrent malignant obstruction who previously had intubation or stent placement. (2) Survival is influenced by better PS (< or =2) and in those with disease Stage III rather than patients in Stage IV. This study has not been able to determine the influence of complete tumour staging on survival because, apart from four patients, all others were Stages III and IV cancer.

Aged↗
PubMed2000

Medical malpractice: the effect of doctor-patient relations on medical patient perceptions and malpractice intentions.

OBJECTIVE: To examine the causal effects of doctor-patient relations and the severity of a medical outcome on medical patient perceptions and malpractice intentions in the event of an adverse medical outcome. DESIGN: Randomized between-subjects experimental design. Patients were given scenarios depicting interactions between an obstetric patient and her physician throughout the patient's pregnancy, labor, and delivery. PARTICIPANTS: One hundred twenty-eight postpartum obstetric patients were approached for participation, of whom 104 completed the study. Main outcome measures Patients' perceptions of physician competence and intentions to file a malpractice claim. RESULTS: Positive physician communication behaviors increased patients' perceptions of physician competence and decreased malpractice claim intentions toward both the physician and the hospital. A more severe outcome increased only patients' intentions to sue the hospital. CONCLUSION: These results provide empiric evidence for a direct, causal effect of the doctor-patient relationship on medical patients' treatment perceptions and malpractice claim intentions in the event of an adverse medical outcome.

Adolescent↗
PubMed1999

Severe hypertensive sequelae in a child with Seckel syndrome (bird-like dwarfism).

We report a 19-year-old male with Seckel syndrome (bird-like dwarfism) who presents with malignant hypertension associated with hypertensive nephrosclerosis, dilated cardiomyopathy, and a ruptured cerebral artery aneurysm. Although end-organ injury due to chronic hypertension occurs frequently in adults, no previous reports of renal insufficiency due to hypertension exist in children or adolescents. We speculate that this patient may have been particularly prone to hypertensive end-organ injury due to his extreme short stature.

Adult↗
PubMed1998

Correlation of ultrasound with postmortem neuropathologic studies in neonates.

We examined the correlation between cranial sonogram and postmortem examination neurodiagnoses in 51 infants (30 boys and 21 girls) who underwent cranial sonogram before death. The mean gestation of the infants at birth was 32 weeks 6 days; the mean birth weight, 1,992 gm; and the mean survival, 27 days. Most infants had several postmortem examination neurodiagnoses; therefore the postmortem examination diagnosis considered to be most significant in terms of clinical management and long-term neurologic function was chosen for each infant and designated as the primary diagnosis. The ability of the cranial sonogram to diagnose the primary diagnosis was then evaluated. The accuracy of the cranial sonogram in defining primary diagnoses was 59%. There were 21 cases (41%) in which cranial sonogram failed to define the primary diagnosis; nine of these could be explained on the basis of the timing of the ultrasound in relation to the age of the lesion or to the microscopic nature of the lesion. In 12 patients the factors causing the failure of cranial sonogram to define primary postmortem examination diagnoses could not be identified. The positive predictive value of a cranial sonogram diagnosis was 77%; the negative predictive value was 19%.

Brain↗
PubMed1997

Predicting contraceptive vigilance in adolescent females: a projective method for assessing ego development.

PURPOSE: To test the hypothesis that ego development would predict contraceptive use. Problems in ego development were defined in terms of three factors: (1) realism, (2) complexity, and (3) discontinuity. METHODS: Forty-one respondents aged 14-17 years were selected from a group of 233 adolescents who were administered a projective pregnancy scenario and participated in a 12-month follow-up. Twenty of these adolescents were randomly selected from the group determined to be effective contraceptive users, while 21 were randomly selected from the group of poor contraceptors. RESULTS: Chi-square test revealed a significant association (p < .0005) between the composite ego maturity (EM) measure and contraceptive outcome (chi 2 = 13.82, with df-1). Low scores on the ego maturity measure predicted poor contraceptive use. EM was unrelated to age but was associated with race (chi 2 = 7.535, .025 < p < .05). However, EM predicted contraceptive use when controlling for the effects of race. CONCLUSIONS: A simple, time-efficient projective pregnancy scenario is an effective way of determining adolescent females at risk for poor contraceptive effectiveness and, therefore, untimely pregnancy. These stories are analyzed using factors related to the ego development of the adolescent. Subjects who scored lower on this measure have poor contraceptive effectiveness while subjects with higher levels demonstrated effective contraception use, at 1-year follow-up.

Adolescent↗
PubMed1997

The roles of constructive thinking and optimism in psychological and behavioral adjustment during pregnancy.

This study examined the impact of constructive thinking on the anxiety, positive states of mind, and substance use of 221 women during pregnancy and the influence of optimism and perceived stress on these relationships. Participants were interviewed both early and late in pregnancy. Constructive thinking predicted both psychological and behavioral adjustment later in pregnancy, independent of age and social desirability. Subsequent path analyses indicated that constructive thinking mediated the impact of optimism on anxiety, positive states of mind, and substance use during pregnancy. In turn, the effect of constructive thinking on women's adjustment during pregnancy was itself mediated by their perceived stress. Implications for constructive thinking and optimism as independent constructs relevant to adjustment and their potential importance for future research and clinical applications are discussed.

Adaptation, Psychological↗