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1.
Trials ; 23(1): 660, 2022 Aug 15.
Article in English | MEDLINE | ID: mdl-35971155

ABSTRACT

BACKGROUND: Coronavirus disease-19 (COVID-19) infection causes persistent health problems such as breathlessness, chest pain and fatigue, and therapies for the prevention and early treatment of post-COVID-19 syndromes are needed. Accordingly, we are investigating the effect of a resistance exercise intervention on exercise capacity and health status following COVID-19 infection. METHODS: A two-arm randomised, controlled clinical trial including 220 adults with a diagnosis of COVID-19 in the preceding 6 months. Participants will be classified according to clinical presentation: Group A, not hospitalised due to COVID but persisting symptoms for at least 4 weeks leading to medical review; Group B, discharged after an admission for COVID and with persistent symptoms for at least 4 weeks; or Group C, convalescing in hospital after an admission for COVID. Participants will be randomised to usual care or usual care plus a personalised and pragmatic resistance exercise intervention for 12 weeks. The primary outcome is the incremental shuttle walks test (ISWT) 3 months after randomisation with secondary outcomes including spirometry, grip strength, short performance physical battery (SPPB), frailty status, contacts with healthcare professionals, hospitalisation and questionnaires assessing health-related quality of life, physical activity, fatigue and dyspnoea. DISCUSSION: Ethical approval has been granted by the National Health Service (NHS) West of Scotland Research Ethics Committee (REC) (reference: GN20CA537) and recruitment is ongoing. Trial findings will be disseminated through patient and public forums, scientific conferences and journals. TRIAL REGISTRATION: ClinicialTrials.gov NCT04900961 . Prospectively registered on 25 May 2021.


Subject(s)
COVID-19/complications , Resistance Training , SARS-CoV-2 , Adult , COVID-19/therapy , Chest Pain , Dyspnea , Fatigue , Humans , Quality of Life , Treatment Outcome , Post-Acute COVID-19 Syndrome
2.
J Parasitol ; 104(1): 31-38, 2018 02.
Article in English | MEDLINE | ID: mdl-29119858

ABSTRACT

A novel coccidian species was discovered in the prostate of an Antechinus flavipes (yellow-footed antechinus) in South Australia during the period of postmating male antechinus immunosuppression and mortality. This novel coccidian is unusual because it develops extraintestinally and sporulates endogenously within the prostate gland of its mammalian host. Histological examination of prostatic tissue revealed dense aggregations of spherical and thin-walled tetrasporocystic, dizoic, sporulated coccidian oocysts within tubular lumina, with unsporulated oocysts and gamogonic stages within the cytoplasm of glandular epithelial cells. This coccidian was observed occurring concurrently with dasyurid gammaherpesvirus 1 infection of the antechinus' prostate. Eimeria-specific 18S small-subunit ribosomal (r)DNA polymerase chain reaction amplification was used to obtain a partial 18S rDNA nucleotide sequence from the antechinus coccidian. Bayesian phylogenetic analysis based on 18S rDNA gene sequences revealed that the novel coccidian clusters with reptile-host coccidians, forming an ancestral basal lineage of the eimeriid clade. The species has been named Eimeria taggarti n. sp. on the basis of both sporulated oocyst morphology and molecular characterization. It is suspected that E. taggarti is sexually transmitted via excretion of sporulated oocysts or free sporocysts with prostatic secretions in semen.


Subject(s)
Coccidiosis/veterinary , Eimeria/isolation & purification , Marsupialia/parasitology , Prostate/parasitology , Prostatic Diseases/veterinary , Animals , Base Sequence , Coccidiosis/parasitology , DNA, Protozoan/chemistry , DNA, Protozoan/isolation & purification , DNA, Ribosomal/chemistry , DNA, Ribosomal/isolation & purification , Eimeria/classification , Eimeria/genetics , Eimeria/ultrastructure , Immune Tolerance , Male , Marsupialia/immunology , Microscopy, Electron, Transmission/veterinary , Oocysts/growth & development , Oocysts/ultrastructure , Phylogeny , Prostatic Diseases/parasitology , RNA, Protozoan/genetics , RNA, Ribosomal, 18S/genetics , Sequence Alignment/veterinary , South Australia
3.
Clin Pharmacol Ther ; 100(1): 88-101, 2016 07.
Article in English | MEDLINE | ID: mdl-26818743

ABSTRACT

Meta-analyses of cell therapy trials for heart disease have yielded discrepant results. To resolve limitations associated with meta-analyses, such as imprecision and accumulation of random errors, we conducted trial sequential analysis (TSA). Randomized controlled trials that administered autologous bone marrow-derived cells to patients who suffered acute myocardial infarction (AMI) or heart failure (HF) were included. TSA has been applied to two clinical outcomes, all-cause mortality and hospitalization for HF, and to left ventricular ejection fraction (LVEF), as a surrogate of heart function. The results suggest that there is evidence of reduction of the risk of mortality and hospitalization in HF, but insufficient evidence to determine treatment effect in AMI. Moreover, the treatment does not improve LVEF by more than a mean difference of 4% when administered to either AMI or HF patients. The required number of participants to include in a meta-analysis to detect treatment effect was also estimated.


Subject(s)
Bone Marrow Transplantation/methods , Heart Failure/therapy , Myocardial Infarction/therapy , Heart Failure/mortality , Hospitalization , Humans , Meta-Analysis as Topic , Myocardial Infarction/mortality , Randomized Controlled Trials as Topic , Research Design , Transplantation, Autologous , Treatment Outcome , Ventricular Function, Left
4.
Anal Bioanal Chem ; 406(19): 4571-83, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24980599

ABSTRACT

The surface chemistry of gold nanowires (AuNWs) has been systematically assessed in terms of contamination and cleaning processes. The nanomaterial's surface quality was correlated to its performance in the matrix-free laser desorption ionization mass spectrometry (LDI-MS) analysis of low molecular weight analytes. Arrays of AuNWs were deposited on glass slides by means of the lithographically patterned nanowire electrodeposition technique. AuNWs were then characterized in terms of surface chemical composition and morphology using X-ray photoelectron spectroscopy, scanning electron microscopy and atomic force microscopy. AuNWs were subjected to a series of well-known cleaning procedures with the aim of producing the best performing surfaces for the LDI-MS detection of leucine enkephalin, chosen as a model analyte with a molar mass below 1,000 g/mol. Prolonged cyclic voltammetry in 2 M sulfuric acid and, most of all, oxygen plasma cleaning for 5 min provided the best results in terms of simpler (interference-free) and more intense mass spectrometry spectra of the reference compound. The analyte always ionized as the sodiated adduct, and leucine enkephalin limits of detection of 0.5 and 2.5 pmol were estimated for the positive and negative analysis modes, respectively. This study points out the tight correlation existing between the chemical status of the nanostructure surface and the AuNW-assisted LDI-MS performance in terms of reproducibility of spectra, intensity of analyte ions and reduction of interferences.


Subject(s)
Enkephalin, Leucine/analysis , Gold/chemistry , Nanowires/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Nanowires/ultrastructure , Photoelectron Spectroscopy
5.
Environ Res ; 133: 388-95, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24948546

ABSTRACT

Several polycyclic aromatic hydrocarbons (PAHs) are known or probable human carcinogens. We evaluated the relationship between PAH exposure and risk of childhood acute lymphoblastic leukemia (ALL) using concentrations in residential dust as an exposure indicator. We conducted a population-based case-control study (251 ALL cases, 306 birth-certificate controls) in Northern and Central California from 2001 to 2007. We collected residential dust using a high volume small surface sampler (HVS3) (n=185 cases, 212 controls) or by sampling from participants' household vacuum cleaners (n=66 cases, 94 controls). We evaluated log-transformed concentrations of 9 individual PAHs, the summed PAHs, and the summed PAHs weighted by their carcinogenic potency (the toxic equivalence). We calculated odds ratios (ORs) and 95% confidence intervals (CI) using logistic regression adjusting for demographic characteristics and duration between diagnosis/reference date and dust collection. Among participants with HVS3 dust, risk of ALL was not associated with increasing concentration of any PAHs based on OR perln(ng/g). Among participants with vacuum dust, we observed positive associations between ALL risk and increasing concentrations of benzo[a]pyrene (OR perln[ng/g]=1.42, 95% CI=0.95, 2.12), dibenzo[a,h]anthracene (OR=1.98, 95% CI=1.11, 3.55), benzo[k]fluoranthene (OR=1.71, 95% CI=0.91, 3.22), indeno[1,2,3-cd]pyrene (OR=1.81, 95% CI=1.04, 3.16), and the toxic equivalence (OR=2.35, 95% CI=1.18, 4.69). The increased ALL risk among participants with vacuum dust suggests that PAH exposure may increase the risk of childhood ALL; however, reasons for the different results based on HVS3 dust samples deserve further study.


Subject(s)
Dust/analysis , Polycyclic Aromatic Hydrocarbons/poisoning , Precursor Cell Lymphoblastic Leukemia-Lymphoma/chemically induced , California/epidemiology , Case-Control Studies , Child , Child, Preschool , Female , Housing , Humans , Infant , Male , Polycyclic Aromatic Hydrocarbons/analysis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/epidemiology
6.
Vet Pathol ; 50(2): 299-307, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22855413

ABSTRACT

The wild and captive koala population of the Mt Lofty Ranges in South Australia has a high level of renal dysfunction in which crystals consistent with calcium oxalate have been observed in the kidneys. This study aimed to describe the pathological features of the renal disease in this population, confirm the composition of renal crystals as calcium oxalate, and determine whether any age or sex predispositions exist for this disease. A total of 51 koalas (28 wild rescues, 23 captive) were examined at necropsy, of which 28 (55%) were found to have gross and/or histological evidence of oxalate nephrosis. Histopathological features included intratubular and interstitial inflammation, tubule dilation, glomerular atrophy, tubule loss, and cortical fibrosis. Calcium oxalate crystals were demonstrated using a combination of polarization microscopy, alizarin red S staining, infrared spectroscopy, and energy-dispersive X-ray analysis with scanning electron microscopy. Uric acid and phosphate deposits were also shown to be present but were associated with minimal histopathological changes. No significant differences were found between the numbers of affected captive and wild rescued koalas; also, there were no sex or age predispositions identified, but it was found that oxalate nephrosis may affect koalas <2 years of age. The findings of this study suggest that oxalate nephrosis is a leading disease in this koala population. Possible causes of this disease are currently under investigation.


Subject(s)
Animals, Wild/metabolism , Animals, Zoo/metabolism , Calcium Oxalate/metabolism , Nephrosis/epidemiology , Nephrosis/veterinary , Phascolarctidae , Age Factors , Animals , Anthraquinones , Kidney/metabolism , Kidney/ultrastructure , Microscopy, Electron, Scanning/veterinary , Nephrosis/metabolism , Nephrosis/pathology , South Australia/epidemiology , Spectrometry, X-Ray Emission/veterinary , Spectrophotometry, Infrared/veterinary
8.
Perfusion ; 27(2): 127-31, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22115880

ABSTRACT

OBJECTIVES: A number of risk factors have been recognised for postoperative renal dysfunction following on-pump coronary artery bypass surgery (CABG). There are, however, few studies that have evaluated the potential reno-protective effects of off-pump CABG in the presence of other confounding risk factors. The aim of this study was to determine if off-pump CABG reduces the risk of renal injury. METHODS: Serum creatinine values (preoperatively and day 1, 2 and 4 postoperatively) and other clinical data were prospectively collected on 1580 consecutive patients who underwent first-time CABG from 2002 to 2005. Creatinine clearance was calculated using the Cockcroft and Gault equation. The effect of on-pump vs. off-pump CABG on renal function was analysed, adjusting for age, gender, diabetes mellitus, left ventricular (LV) function and preoperative creatinine clearance, using multiple regression analysis. RESULTS: One thousand one hundred and forty-five (73%) patients underwent on-pump CABG and 435 (27%) underwent off-pump CABG. The two groups were similar with respect to age, gender and diabetes. Two hundred and seventy-four (17%) patients were females and 274 (17%) patients had diabetes. Multivariate analysis demonstrated significantly lower creatinine clearance postoperatively in patients with diabetes (P<0.001) and advanced age (P<0.001). The on-pump group had significantly lower postoperative creatinine clearance in comparison to the off-pump group (P= 0.01). The effect remained consistent after adjusting for potential risk factors (age, diabetes, gender, LV function and preoperative creatinine clearance) in the multivariate analysis. CONCLUSION: Off-pump surgery is associated with a reduction in postoperative renal injury.


Subject(s)
Coronary Artery Bypass/adverse effects , Creatinine/blood , Kidney Diseases/etiology , Kidney/physiopathology , Postoperative Complications/etiology , Aged , Cardiopulmonary Bypass , Coronary Artery Bypass, Off-Pump/adverse effects , Female , Humans , Male , Middle Aged , Postoperative Period , Risk Factors
9.
Heart ; 95(23): 1937-43, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19687014

ABSTRACT

AIMS: Myocardial revascularisation improves outcomes in patients with coronary artery disease. However, these procedures may themselves cause irreversible myocardial injury. The prognostic value of procedural myocardial injury is uncertain. METHODS AND RESULTS: We quantified procedural myocardial necrosis using delayed enhancement cardiovascular magnetic resonance imaging (DE-CMR) in 152 consecutive patients before and shortly after percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The primary endpoint was defined as death, non-fatal myocardial infarction, sustained ventricular arrhythmia, unstable angina or heart failure requiring hospitalisation. During a median follow-up of 2.9 years, 27 patients (18%) reached the primary endpoint. 49 patients (32%) had evidence of new procedure-related myocardial hyperenhancement with a median mass of 5.0 g (interquartile range 2.7-9.8). After adjustment for age and sex, these patients had a 3.1-fold (95% confidence interval 1.4 to 6.8; p = 0.004) higher risk of adverse outcome than patients without new hyperenhancement. Cardiac troponin levels and quantitative measures of left ventricular function after procedure did not show any significant independent association with the primary endpoint and they did not alter the independent association of new hyperenhancement. CONCLUSIONS: Myocardial injury during PCI or CABG, identified by DE-CMR, adversely affects clinical outcome. This suggests the benefits from revascularisation could partially be offset by new myocardial injury caused by the intervention itself.


Subject(s)
Acute Coronary Syndrome/therapy , Angina Pectoris/therapy , Angioplasty, Balloon, Coronary/adverse effects , Coronary Artery Bypass/adverse effects , Myocardial Reperfusion Injury/diagnosis , Acute Coronary Syndrome/mortality , Angina Pectoris/mortality , Angioplasty, Balloon, Coronary/mortality , Coronary Artery Bypass/mortality , Female , Humans , Kaplan-Meier Estimate , Magnetic Resonance Angiography/methods , Magnetic Resonance Angiography/mortality , Male , Middle Aged , Myocardial Infarction/diagnosis , Myocardial Infarction/mortality , Myocardial Infarction/therapy , Myocardial Reperfusion Injury/etiology , Myocardial Reperfusion Injury/mortality , Prognosis
10.
Q J Nucl Med Mol Imaging ; 52(4): 403-18, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19088694

ABSTRACT

Neuroblastoma is an embryonic tumor of the peripheral sympathetic nervous system, and is able to take up, store and secrete catecholamine metabolites. Neuro-blastoma is metastatic or otherwise high risk for relapse in nearly 50% of cases, with a long-term survival of <40%, necessitating new approaches to therapy. The tumor cells express the norepinephrine transporter, which makes metaiodobenzylguanidine (MIBG), an analogue of norepinephrine, an ideal tumor specific agent for imaging and therapy, when labeled with (123)I or (131)I. This article will briefly review the use of [(123)I]MIBG imaging for monitoring therapy in neuroblastoma, and concentrate on the past, current and planned clinical trials using [(131)I]MIBG as targeted radiotherapy. The administration guidelines, toxicity, response and survival are discussed. Various therapeutic approaches include MIBG monotherapy, sequential infusion, and combination therapy. Treatment with MIBG has been tested as induction therapy, part of consolidation, and as treatment for relapse. The high response rates of 30-40% using MIBG monotherapy in relapsed neuroblastoma, and the low non-hematologic toxicity make this an ideal agent for incorporation into standard therapy of high-risk neuroblastoma.


Subject(s)
3-Iodobenzylguanidine/therapeutic use , Neuroblastoma/diagnosis , Neuroblastoma/radiotherapy , 3-Iodobenzylguanidine/administration & dosage , 3-Iodobenzylguanidine/adverse effects , Humans , Neuroblastoma/pathology , Radiation-Sensitizing Agents/administration & dosage , Radiation-Sensitizing Agents/therapeutic use , Radiometry , Recurrence , Staining and Labeling
11.
Nano Lett ; 8(8): 2447-51, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18624390

ABSTRACT

We describe the preparation by electrodeposition of arrays of lead telluride (PbTe) nanowires using the lithographically patterned nanowire electrodeposition (LPNE) method. PbTe nanowires had a rectangular cross-section with adjustable width and height ranging between 60-400 nm (w) and 20-100 nm (h). The characterization of these nanowire arrays using X-ray diffraction, transmission electron microscopy and electron diffraction, scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy (XPS) is reported. PbTe nanowires were electrodeposited using a cyclic electrodeposition-stripping technique that produced polycrystalline, stoichiometric, face-centered cubic PbTe with a mean grain diameter of 10-20 nm. These nanowires were more than 1 mm in length and two additional processing steps permitted their suspension across 25 microm air gaps microfabricated on these surfaces. The LPNE synthesis of lithographically patterned PbTe nanowires was carried out in unfiltered laboratory air. Nanowires with lengths of 70-100 microm showed an electrical resistivity comparable to bulk PbTe. XPS reveals that exposure of PbTe nanowires to air causes the formation on the nanowire surface of approximately one monolayer of a mixed lead oxide and tellurium oxide within a few minutes.

12.
Reprod Fertil Dev ; 20(2): 275-80, 2008.
Article in English | MEDLINE | ID: mdl-18255017

ABSTRACT

Male semelparous dasyurid species are annual breeders that use a promiscuous mating system. These species have shown biases in litter sex ratios and, with females producing more young than they have available teats, this provides an opportunity for the manipulation of the sex ratio at birth. The sex ratio of embryos and pouch young, and the degree of embryonic overproduction, in red-tailed phascogales (Phascogale calura) was investigated to gain an understanding of the mechanism by which sex biases may be generated. The sex ratio of embryos did not differ from parity, but a male bias was observed in young attaching to teats. Females produced an average of 15.1 +/- 1.9 corpora lutea and 10.5 +/- 3.5 viable embryos, with no difference in fecundity observed with female age or weight. Because females only have eight teats, the overproduction of young, and male-biased attachment, was sufficient to explain the observed male bias in pouch young. No relationship was observed between maternal weight and sex ratio, but heavier females did tend to produce more ova. Meta-analysis of studies providing information on litter sex ratios in male semelparous dasyurid species did not show any consistent trend.


Subject(s)
Animals, Suckling/physiology , Competitive Behavior/physiology , Marsupialia/physiology , Sex Ratio , Analysis of Variance , Animals , Body Weight , Corpus Luteum/physiology , DNA Primers/genetics , Female , Male , Northern Territory , Sex Determination Analysis
13.
Anim Reprod Sci ; 99(3-4): 363-76, 2007 Jun.
Article in English | MEDLINE | ID: mdl-16884866

ABSTRACT

This study investigates the effect of three exogenous gonadotrophin regimens on ovarian follicular development in southern hairy-nosed wombats during the non-breeding season. Females were given either porcine follicle stimulating hormone (pFSH; total of 200 mg at 12 h intervals over 7 (Group 1), or 4 days (Group 2)), or pregnant mares' serum gonadotrophin (PMSG; single dose of 150 I.U. (Group 3)). In all treatment groups 25 mg of porcine luteinising hormone (pLH) was used to trigger maturation; Groups 1 and 2 received pLH 12 h after the final pFSH injection and Group 3 received pLH 72 h after PMSG. The results showed Group 1 produced significantly more follicles per ovary (5.91+/-1.28) than Group 2 (1.67+/-0.62), or Group 3 (2.17+/-1.16) at p<0.05. Control females received saline injections concurrently with the three treatment groups (n=6; 2 control animals for each treatment group). No follicular development occurred in any control female. Analysis of oocyte nuclear status revealed that while oocytes from all three treatment groups had resumed meiosis, only those in Group 1 (7-day pFSH/pLH treatment) progressed to metaphase II. These results have implications for the development of assisted breeding strategies in this species.


Subject(s)
Anestrus/drug effects , Marsupialia/physiology , Oocytes/drug effects , Ovarian Follicle/drug effects , Superovulation/drug effects , Anestrus/physiology , Animals , Female , Follicle Stimulating Hormone/pharmacology , Gonadotropins, Equine/pharmacology , Hormones/pharmacology , Luteinizing Hormone/pharmacology , Oocytes/cytology
14.
Anim Reprod Sci ; 100(1-2): 216-22, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17023125

ABSTRACT

The southern hairy-nosed wombat (Lasiorhinus latifrons) is a seasonal breeding, burrowing marsupial adapted to a semi-arid environment and the closest relative of the endangered northern hairy-nosed wombat (Lasiorhinus krefftii). Females typically give birth to one to two young every 3 years with young weaned at 360-400 days. This study examined the occurrence of polyoestry in a wild population of southern hairy-nosed wombats, and in particular the ability of this species to produce additional offspring in the same breeding season if a young was prematurely lost or removed. Pouch young were removed during the breeding seasons of 1996/1997 and 2003. No females from the 1996 (n=3)/1997 (n=3) group gave birth to a second pouch young in the same breeding season. However, two females in this group gave birth to young the following season. In contrast, all the 2003 group of females (n=6) produced a second offspring in the same breeding season after removal of pouch young (RPY). The reason for the different response to RPY between the two groups is unknown. These studies confirm that southern hairy-nosed wombats are polyoestrus in the wild and are capable of producing more than one offspring in a single breeding season. Females that failed to return to oestrus in the breeding season that pouch young were removed bred again in the following season. Rapid replacement of southern hairy-nosed wombat pouch young in the same breeding season as RPY suggests that this procedure, linked to either hand-rearing or interspecific cross-fostering, should be seriously considered as a priority conservation action to increase the population size of the critically endangered sister species, the northern hairy-nosed wombat.


Subject(s)
Estrous Cycle/physiology , Marsupialia/physiology , Animals , Female
16.
Gen Comp Endocrinol ; 149(3): 236-43, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16884721

ABSTRACT

The semelparous dasyurids display a unique life history, in that all males die within a few weeks of the completion of the breeding season. Studies of several semelparous species have revealed that the male die-off is stress-related, and accompanied by increased plasma androgen and cortisol levels and decreased corticosteroid binding capacity, resulting in suppression of immune and inflammatory responses. This study examines the endocrine profile of male brush-tailed phascogales (Phascogale tapoatafa) that survive beyond the breeding season in captivity. Plasma cortisol, corticosteroid binding globulin and albumin levels were monitored in both males and females and steroid partitioning calculated. Captive males surviving beyond the breeding season did not show the elevation in plasma cortisol and decrease in corticosteroid binding capacity reported in wild males. Plasma albumin concentrations also remained constant during the sampling period. These data indicate that captive males do not undergo the same stress response described in wild populations.


Subject(s)
Breeding , Hydrocortisone/blood , Marsupialia/physiology , Transcortin/metabolism , Animals , Feedback, Physiological , Female , Male , Marsupialia/blood , Serum Albumin/metabolism
17.
Reprod Fertil Dev ; 18(4): 477-84, 2006.
Article in English | MEDLINE | ID: mdl-16737641

ABSTRACT

The effect of the exogenous administration of porcine follicle-stimulating hormone (pFSH) and pregnant mare serum gonadotrophin (PMSG) on ovarian follicular development and oocyte maturation in the southern hairy nosed wombat Lasiorhinus latifrons was investigated. Three experimental groups were administered pFSH at various doses and for different treatment lengths, followed by 25 mg porcine luteinising hormone (pLH) 12 h after the last dose of pFSH. Another group was given PMSG followed 72 h later by 25 mg pLH. Animals were killed 24 h after pLH. The left ovary was fixed for histology and the morphology of the antral follicles was determined, whereas follicular oocytes in the right ovary were aspirated, fixed, stained with 42,62-diamidino-2-phenylindole, and viewed for nuclear maturation. There was no significant difference in the mean number of ovarian follicles >1 mm, or in the size class of follicles assessed between control and experimental groups. However, a trend was observed suggesting a possible increase in follicles >3.0 mm in experimental groups compared with control animals. In all females administered exogenous porcine gonadotrophins, but not controls, some of the mural granulosa cells of large tertiary antral follicles had markedly enlarged nuclei (approximately 14 microm in diameter). All oocytes from the control group remained at the germinal vesicle stage, whereas approximately 40% of oocytes retrieved from the pFSH groups and 82.4% retrieved from the PMSG-primed animals had undergone germinal vesicle break down, with a small number reaching meiosis II. The present study shows that exogenous administration of either pFSH or PMSG to hairy nosed wombats can induce follicular growth and oocyte maturation. Such findings could be useful in the development of reproductive technology in this species.


Subject(s)
Gonadotropins, Pituitary/pharmacology , Marsupialia , Oocytes/drug effects , Ovary/drug effects , Seasons , Animals , Breeding , Female , Follicle Stimulating Hormone/pharmacology , Gonadotropins, Equine/pharmacology , Granulosa Cells/cytology , Granulosa Cells/drug effects , Luteinizing Hormone/pharmacology , Oocytes/physiology , Ovarian Follicle/anatomy & histology , Ovarian Follicle/physiology , Ovary/anatomy & histology
18.
Anim Reprod Sci ; 95(3-4): 295-306, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16289971

ABSTRACT

There is limited information available on the oestrous cycle of female southern hairy-nosed wombats (Lasiorhinus latifrons). This is mainly due to an extremely poor breeding success in captivity and the difficulty in routine recapturing of these cryptic, semi-fossorial animals in the wild. The aim of this study was to characterise the oestrous cycle of this species by monitoring peripheral plasma concentrations of progesterone and oestradiol, assessing changes in vaginal cytology, pouch condition and the urogenital sinus. Eight adult female wombats were monitored during the breeding season (July-December) over 2 years (2002-2003). Samples were collected up to three times a week. Vaginal smears contained several cell types, categorised by morphology, as either superficial epithelial cells or parabasal-intermediate cells. Leucocytes were also counted. Plasma progesterone profiles showed a mean oestrous cycle length of 36.33+/-0.67 days with a peak progesterone concentration of 139.53+/-10.62nmol/L. Levels of oestradiol peaked at a mean level of 467.33+/-44.32pmol/L on average 5 days before a rise in plasma progesterone values. The proportion of epithelial cells in vaginal smears varied throughout the cycle, with a high percentage of superficial epithelial cells observed during the follicular phase. During periods when progesterone concentrations were high, a greater percentage of parabasal-intermediate cells was observed. In conclusion, this study has characterised the oestrous cycle of the southern hairy-nosed wombat and confirmed that changes in vaginal smears together with pouch and urogenital sinus details could be used to determine signs of oestrus in this species.


Subject(s)
Estrous Cycle/physiology , Marsupialia/physiology , Animals , Breeding , Epithelial Cells , Estradiol/blood , Female , Leukocyte Count , Marsupialia/anatomy & histology , Progesterone/blood , Seasons , South Australia , Time Factors , Urogenital System/anatomy & histology , Vagina/cytology , Vaginal Smears/veterinary
19.
Reproduction ; 130(3): 367-78, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16123244

ABSTRACT

Changes in semen quality and morphology of the male reproductive tract were studied throughout the year in the highly promiscuous tammar wallaby. Body size, semen quality and gross morphology of the reproductive organs were assessed in adult males each month from January to November. The mean weight of males was similar in most periods sampled, but males were slightly heavier in the minor (P < 0.05) than the non-breeding season. Since body weight was correlated with weights of the testes, epididymides and accessory sex glands, organ weights were adjusted for body weight in subsequent analyses. In the major breeding season (late January/early February), when most females go through a brief, highly synchronized oestrus, the testes, prostate, Cowper's glands, crus penis and urethral bulb were heaviest, volume and coagulation of ejaculates were greatest, and sperm motility had increased. Semen samples collected by electroejaculation at this time contained low numbers of spermatozoa, possibly as a result of dilution and entrapment by the seminal coagulum or depletion of epididymal stores during intense multiple mating activity. In the non-breeding season (late May-July), when mating does not normally occur in the wild, there was a significant decrease in the relative weight of nearly all male reproductive organs and a decline in most semen parameters. In the minor breeding season (September-November), when pubertal females undergo their first oestrus and mating, the weights of testes, epididymides and most accessory sex glands had significantly increased similar to those of males in the major breeding season. The total number and motility of ejaculated spermatozoa were highest during this period, but the volume and coagulation of ejaculates and weight of the prostate had only increased to levels that were intermediate between the major and non-breeding seasons. Ejaculate volume was strongly correlated with prostate weight, and % motile spermatozoa was strongly correlated with epididymis weight. Semen quality thus varied seasonally with changes in androgen-dependent reproductive organs in the male tammar wallaby and appeared to be influenced by the seasonal timing of oestrus in females. Semen quality may also improve in response to an increase in the number of available oestrous females.


Subject(s)
Estrus/physiology , Genitalia, Male/anatomy & histology , Macropodidae/anatomy & histology , Seasons , Semen/physiology , Animals , Body Weight , Epididymis/anatomy & histology , Female , Macropodidae/physiology , Male , Organ Size , Prostate/anatomy & histology , Sperm Motility , Testis/anatomy & histology
20.
J Thorac Cardiovasc Surg ; 126(4): 1061-4, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14566247

ABSTRACT

OBJECTIVE: Cognitive dysfunction and postoperative hypoxia are common sequelae of coronary artery bypass grafting, but there has been no study to determine whether there is any relationship between them. METHODS: Arterial blood gas measurements were performed before surgical intervention and on the second and fifth postoperative day, and neuropsychological assessments were performed before surgical intervention and 5 days and 3 months postoperatively by using a battery of 10 psychometric tests in 175 patients undergoing coronary artery bypass grafting. An estimate of overall performance on the battery at each assessment point was provided by a simple aggregate cognitive index score calculated from the mean z scores of 4 normally distributed test variables. Multiple regression analysis was performed by using the cognitive index score at day 5 as the dependent variable, with age, sex, duration of the operation, presence or absence of cardiopulmonary bypass, preoperative cognitive index score, and arterial oxygenation and percentage of saturation at day 5 as independent variables. RESULTS: The mean cognitive index score decreased significantly in 115 (66%) patients who agreed to neuropsychological test battery assessment on the fifth postoperative day but improved significantly beyond baseline at 3 months. Mean arterial oxygen tension and percentage of saturation decreased significantly 2 days after the operation and, although improving over the following 3 days, remained decreased at day 5. Decreased cognitive index scores at day 5 strongly predicted cognitive impairment at 3 months (r = 0.36). The only significant independent predictors of the day 5 cognitive index score in the multiple regression analysis were preoperative cognitive index score and arterial oxygenation tension at day 5 (r = 0.24, P <.03). CONCLUSIONS: We report a significant correlation between postoperative cognitive dysfunction and hypoxia 5 days after coronary artery bypass grafting. This finding might have therapeutic implications because early postoperative cognitive dysfunction influences long-term impairment.


Subject(s)
Cognition Disorders/etiology , Coronary Artery Bypass , Hypoxia/complications , Humans , Neuropsychological Tests , Oxygen/blood , Postoperative Complications , Psychometrics , Regression Analysis
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