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2.
Aust Vet J ; 102(3): 51-59, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38148575

ABSTRACT

This was a prospective cohort study to determine how events from birth until first calving affect reproductive performance in the first lactation in pasture-based dairy herds in Victoria, Australia. Events during the preweaning (0 to 84 days), weaning to first breeding (85 to 473 days) and first breeding to first calving periods (474 to 804 days) were recorded and their association with reproductive performance during the first lactation was quantified. Reproductive performance outcomes included the number of days from first mating start date to first service (MSD-S1) and the number of days from first mating start date to first conception (MSD-CON). Predictors for reproductive performance included: passive transfer status as a calf; season of birth; age and breed of the dam; breed; the presence or absence of dystocia at the time of the heifer's birth; active feeding of colostrum versus being left on the dam for colostrum intake; presence of twinning; the presence or absence of preweaning diarrhoea; preweaning, prepubertal and postpubertal average daily gain; the presence or absence of periparturient disease at first calving; age at first calving; body condition score at first calving; sex of the first-born calf; the presence or absence of a stillborn calf at the first calving and requirement of assistance at first calving. Two Cox proportional hazards regression models were developed: the first for early life event variables associated with MSD-S1 and the second for early life events associated with MSD-CON. Heifers born in autumn and winter had 2.89 (95% CI 1.50 to 5.59, P = 0.002) times and 1.97 (95% CI 1.12 to 3.44, P = 0.018) times the daily hazard of being inseminated compared with heifers born in spring, respectively. For the MSD-S1 analyses heifers that gave birth to a live calf had 1.64 (95% CI 1.14 to 2.36, P = 0.008) times the daily hazard of being inseminated compared with heifers that had a stillborn calf. Increases in weight gain during the first breeding to first calving period by 0.1 kg/day increments increased the daily hazard of first insemination by a factor of 1.10 (95% CI 1.00 to 1.22, P = 0.043). Heifers that experienced periparturient disease had a significantly lower hazard of conception per day compared with heifers that did not experience periparturient disease at the first calving (HR 0.67, 95% CI 0.50 to 0.91, P = 0.009). Increases in weight gain during the first breeding to first calving period by 0.1 kg/day increased the daily hazard of conception by a factor of 1.10 (95% CI 1.01 to 1.21, P = 0.038). We conclude that of all the growth periods assessed in this study, events that occurred during the first breeding to first calving period (474 to 804 days) had the greatest association with reproductive performance in the first lactation. There should be a focus on increasing growth rates during this period and reducing the risk of stillbirth and periparturient disease to improve reproductive performance in the subsequent mating period after calving.


Subject(s)
Lactation , Reproduction , Humans , Pregnancy , Cattle , Animals , Female , Prospective Studies , Weight Gain , Victoria
3.
Eur Rev Med Pharmacol Sci ; 26(22): 8481-8501, 2022 11.
Article in English | MEDLINE | ID: mdl-36459030

ABSTRACT

In recent years, the advanced knowledge of clinical, biological and molecular features of prostate cancer have led to the introduction of new drugs and have allowed the relocation of old drugs in different settings. In this way, the new concepts of systemic disease arise: high risk or high volume vs. low risk and low volume disease castration sensitive prostate cancer (CSPC), diversifying the use of previously approved drugs (CRPC) and opening new scenarios for sequence therapy. The aim of this review is to integrate new developments into the medical management of systemic prostate cancer.


Subject(s)
Prostatic Neoplasms , Male , Humans , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/surgery , Immunotherapy , Algorithms , Knowledge , Castration
4.
G Chir ; 39(3): 158-165, 2018.
Article in English | MEDLINE | ID: mdl-29923485

ABSTRACT

OBJECTIVE: This study aims to evaluate the percentage of cyto-histologic correlation in patients with a thyroid disease documented through clinical-instrumental, cytological (FNAB), histological and surgical examinations. The purpose of this study is also to determine the percentage of disease incidence and evaluating any surgical indication in relation to biological behavior (benign, malignant or indeterminate lesions, occult carcinomas), sex, and age. BACKGROUND: Almost all of thyroid neoplasms is manifested through thyroid nodule. Therefore, clinical evidence of the thyroid nodule analysis is primarily related to the need to exclude malignant pathology or carcinoma of the thyroid, present in 4-6.5% of cases. PATIENTS AND METHODS: The trial was conducted analyzing the data including cytological and histology thyroid reports recorded from 1 March 2010 to 1 March 2016, for a total of 5,956 reports. To determine the cyto-histological correlations, have been considered eligible all patients of both sexes, that have performed at least one cytologic exam followed by an histologic exam. Thus, the total number of the cases studied is 554 cases. RESULTS: Cyto-histologic compliance was 93% with a diagnostic accuracy of 4% higher than the literature examined. CONCLUSIONS: The results thus obtained show, furthermore, that there is a non-negligible percentage of thyroid disease with malignant biological behavior and involvement of male individuals. Therefore, the execution of the FNAB is of utmost importance for the purpose of a correct surgical indication.


Subject(s)
Thyroid Neoplasms/pathology , Thyroidectomy , Adenocarcinoma, Follicular/pathology , Adenocarcinoma, Follicular/surgery , Adenoma/pathology , Adenoma/surgery , Adenoma, Oxyphilic/pathology , Adenoma, Oxyphilic/surgery , Adult , Age Distribution , Aged , Biopsy, Fine-Needle , Carcinoma, Papillary/pathology , Carcinoma, Papillary/surgery , Databases, Factual , Female , Humans , Incidence , Male , Middle Aged , Retrospective Studies , Sex Distribution , Thyroid Diseases/pathology , Thyroid Diseases/surgery , Thyroid Neoplasms/classification , Thyroid Neoplasms/surgery , Thyroid Nodule/pathology , Thyroid Nodule/surgery
5.
Aust Vet J ; 96(4): 111-119, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29577251

ABSTRACT

OBJECTIVE: To describe reproductive performance of lactating dairy cows after fixed-time artificial insemination (FTAI) with ovulation synchronisation and re-synchrony in Australian dairy herds, and to compare reproductive outcomes with those of conventional mating programs. METHODS: The study was conducted in two seasonally calving dairy herds in which lactating dairy cows (n = 675) were enrolled into three treatment groups: group 1, oestrus detection and AI for 34 days followed by a natural service period; group 2, FTAI on day 1 followed by re-synchrony of all cows prior to ultrasound pregnancy diagnosis at day 31 and FTAI of cows diagnosed not pregnant at day 34, then a natural service period; group 3, FTAI on day 1 followed by oestrus detection and AI for 34 days, then a natural service period. First-service conception rate (FSCR), 6-week in-calf (6WIC) rate and proportions pregnant at the end of mating were compared using logistic regression with farm fitted as a fixed effect. Times from mating start date to conception were described using survival analysis with Kaplan-Meier failure functions. RESULTS: FSCRs (45.3%, 49.1% and 45.6% for groups 1, 2 and 3, respectively) and proportions pregnant at the end of mating (77.6%, 76.0% and 76.8% for groups 1, 2 and 3, respectively) were similar for all groups. The 6WIC rate in group 2 was similar to that in group 3 (70.4% vs. 67.2%; P = 0.486), but tended to be higher than in group 1 (70.4% vs. 62.0%, P = 0.066). The median days to pregnancy for cows that conceived was 1 day in groups 2 and 3 and 10 days in group 1. CONCLUSION: Mating plans that use FTAI with ovulation synchronisation and re-synchrony during the AI period can achieve comparable reproductive performance to conventional mating programs in seasonally calving dairy herds.


Subject(s)
Cattle/physiology , Dairying/methods , Estrus Synchronization , Insemination, Artificial/veterinary , Pregnancy, Animal , Animals , Australia , Dairying/statistics & numerical data , Estrus Detection/methods , Female , Insemination, Artificial/methods , Pregnancy
6.
J Dairy Sci ; 101(4): 3488-3500, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29395140

ABSTRACT

This was a prospective cohort study to determine how events from birth until first calving affect performance during the first lactation in pasture-based dairy herds in Victoria, Australia. Events during the preweaning (0-84 d), prepubertal (85-473 d), and postpubertal (474-804 d) periods were recorded in 6 herds, and their association with first-lactation 100-d and 250-d total milk, fat, and protein yields was quantified. Predictors of first-lactation performance included passive transfer status as a calf; season of birth; age of dam; the presence or absence of dystocia at the time of the heifer's birth; the presence or absence of preweaning diarrhea; preweaning, prepubertal, and postpubertal average daily weight gain; age at first calving; the presence or absence of periparturient disease at first calving; sex of the first-born calf; the presence or absence of a stillborn calf at the first calving; and requirement of assistance at the first calving. Lactation performance was quantified using cumulative 100-d and 250-d milk, fat, and protein yields estimated from herd recording. A multivariable linear regression model was developed for each outcome: cumulative 100-d milk, fat, and protein yield and cumulative 250-d milk, fat, and protein yield. Heifers that experienced dystocia at the time of their birth produced 7.6 kg [95% confidence interval (CI): 1.8-13.3] less fat and 4.8 kg (95% CI: 0.6-8.9) less protein at 100 d in milk in the first lactation compared with heifers that were delivered without dystocia. Heifers born in the summer and autumn produced 20 L (95% CI: 0.8-40) more milk and 20 kg (95% CI: 5.9-33) more protein at 250 d in milk in the first lactation compared with heifers born in the spring. For 100 g/d increases in prepubertal average daily gain, heifers produced an additional 182 L (95% CI: 149-216) of milk, 4.1 kg (95% CI: 2.8-5.5) of fat, and 4.0 kg (95% CI 3.1-5.0) of protein at 100 d in milk and an additional 345 L (95% CI 264-425) of milk, 6.1 kg (95% CI 3.2-9.0) of fat, and 7.5 kg (95% CI 5.3-9.7) of protein at 250 d in milk. Postpubertal average daily gain was positively associated with 100-d milk yield and 250-d milk yield and protein production. We conclude that of all the growth periods assessed in this study, events that occurred during the prepubertal period (85-473 d of age) had the greatest effect on first-lactation performance.


Subject(s)
Cattle/physiology , Lactation , Animal Husbandry , Animals , Female , Parturition , Pregnancy , Prospective Studies , Victoria
7.
Aust Vet J ; 95(11): 421-426, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29076220

ABSTRACT

OBJECTIVE: The aim of this study was to identify factors affecting colostrum quality in dairy cattle. METHODS: Colostrum samples were collected from lactating dairy cows (n = 990) from nine commercial dairy herds in south-west Victoria. Colostrum quality was measured using an optical Brix refractometer. Cow-level factors thought to influence colostrum quality included season of calving, dam breed and age, volume of first-milking colostrum produced and whether the dam leaked colostrum prior to calving. Multivariable logistic regression was used to quantify the association between each cow-level factor and whether or not colostrum was assessed to be of poor quality. RESULTS: Cows older than 5 years of age were less likely to have poor-quality colostrum compared with primiparous heifers (odds ratio (OR) 0.62, 95% confidence interval (CI) 0.11-0.89, P = 0.009). The odds of having poor-quality colostrum was increased in cows and primiparous heifers that leaked colostrum prior to calving (OR 2.06, 95% CI, 1.33-3.17, P = 0.001). Cows and primiparous heifers that produced ≥ 8.5 L of colostrum were 1.76 times as likely to have poor-quality colostrum as individuals that produced < 8.5 L (95% CI, 1.10-2.82, P = 0.018). Visual assessment of colostrum by the herd manager was moderately correlated with colostrum quality, with 69% of poor-quality samples being correctly classified. CONCLUSION: Although this study identified factors that increase the risk of poor-quality colostrum, we concluded that objective assessment using a Brix refractometer is a more reliable means of assessing colostrum quality.


Subject(s)
Cattle/physiology , Colostrum/immunology , Immunoglobulin G/analysis , Animals , Dairying , Female , Lactation , Logistic Models , Pregnancy , Refractometry/veterinary , Victoria
8.
Faraday Discuss ; 194: 283-303, 2016 12 16.
Article in English | MEDLINE | ID: mdl-27711831

ABSTRACT

The development of free electron laser (FEL) sources has provided an unprecedented bridge between the scientific communities working with ultrafast lasers and extreme ultraviolet (XUV) and X-ray radiation. Indeed, in recent years an increasing number of FEL-based applications have exploited methods and concepts typical of advanced optical approaches. In this context, we recently used a seeded FEL to demonstrate a four-wave-mixing (FWM) process stimulated by coherent XUV radiation, namely the XUV transient grating (X-TG). We hereby report on X-TG measurements carried out on a sample of silicon nitride (Si3N4). The recorded data bears evidence for two distinct signal decay mechanisms: one occurring on a sub-ps timescale and one following slower dynamics extending throughout and beyond the probed timescale range (100 ps). The latter is compatible with a slower relaxation (time decay > ns), that may be interpreted as the signature of thermal diffusion modes. From the peak intensity of the X-TG signal we could estimate a value of the effective third-order susceptibility which is substantially larger than that found in SiO2, so far the only sample with available X-TG data. Furthermore, the intensity of the time-coincidence peak shows a linear dependence on the intensity of the three input beams, indicating that the measurements were performed in the weak field regime. However, the timescale of the ultrafast relaxation exhibits a dependence on the intensity of the XUV radiation. We interpreted the observed behaviour as the generation of a population grating of free-electrons and holes that, on the sub-ps timescale, relaxes to generate lattice excitations. The background free detection inherent to the X-TG approach allowed the determination of FEL-induced electron dynamics with a sensitivity largely exceeding that of transient reflectivity and transmissivity measurements, usually employed for this purpose.

9.
Med. infant ; 23(3): 199-205, Sept.2016. tab, ilus
Article in Spanish | LILACS | ID: biblio-883936

ABSTRACT

El periodo post operatorio a la cirugía cardiaca es complejo y la nutrición juega un rol fundamental dentro de los cuidados. Luego de una cirugía que requiere bypass cardiopulmonar, los neonatos experimentan una profunda respuesta metabólica al stress. Si esta respuesta ocurre sin un soporte nutricional adecuado, la malnutrición lleva a la pérdida de masa magra y al deterioro de la función de órganos vitales. Objetivo: Describir el estado nutricional y el aporte nutricional alcanzado en niños menores de 3 meses con cirugía cardiovascular durante la implementación de un programa de soporte nutricional intensivo evaluado al ingreso, al tercer y séptimo día post operatorio. Resultados: Se estudiaron 64 pacientes. Se logró la implementación de nutrición parenteral total (NPT) en todos los pacientes que ingresaron al protocolo y que requirieron nutrición parenteral. El promedio de volumen recibido en este periodo fue de 50 ml/kg/día (rango entre 25 y 80 ml/kg/día).Las evaluaciones al ingreso, a las 72 hs. y a la semana post operatoria mostraron que el 70%, 69%y 62,7% respectivamente de los pacientes no llegaron a las 67 kcal/kg/ día propuestas para la intervención nutricional para nuestro objetivos. Por el contrario se encontró que el aporte energético enteral y parenteral administrado en los 3 tiempos estudiados logró cubrir el 100% de los requerimientos metabólicos en reposo (REE) estimados por las fórmulas de Schofield y WHO con resultados similares sin diferencias significativas entre ambas. Conclusión: a pesar de no haber logrado cumplir con el objetivo nutricional calórico propuesto por nuestra intervención nutricional, el mismo logro cubrir el 100% del REE calculado por fórmulas (AU)


The postoperative period after heart surgery is complex and nutrition has a key role in the care process. After a surgery that requires cardiopulmonary bypass, neonates have a severe metabolic response to stress. If this response occurs without adequate nutritional support, malnourishment leads to loss of lean body mass and deterioration of vital organ function. Aim: To describe the nutritional status and nutritional support achieved in infants under 3 months of age who underwent cardiovascular surgery during the implementation of an intensive nutritional support program evaluated on admission and on the third and seventh day postoperatively. Results: Overall, 64 patients were studied. The implementation of total parenteral nutrition (TPN) was achieved in all patients that were included in the protocol and required parenteral nutrition. Median volume administered in this period was 50 ml/kg/day (range, from 25 and 80 ml/kg/day). Evaluation on admission, at 72 hs. and at 1 week postoperatively showed that 70%, 69%, and 62.7% of the patients, respectively, did not achieve the 67 kcal/kg/day proposed as the aim for the nutritional intervention. Conversely, it was found that enteral and parenteral energy delivery administered in the three time points was able to cover 100% of the resting energy expenditure (REE) calculated by the Schofield and WHO formalas with similar results without significant differences. Conclusion: Although the nutritional caloric aim a proposed by our nutritional intervention could not be reached, it was able to cover 100% of the REE calculated using the formulas (AU)


Subject(s)
Humans , Infant, Newborn , Infant , Enteral Nutrition , Heart Defects, Congenital/surgery , Intensive Care Units, Pediatric , Nutritional Requirements , Nutritional Support , Parenteral Nutrition , Postoperative Care , Prospective Studies
11.
Aust Vet J ; 90(4): 122-9, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22443326

ABSTRACT

OBJECTIVE: Compare real-time reverse transcription polymerase chain reaction (qRT-PCR), a commercially available enzyme-linked immunosorbent assay (ELISA) and lateral flow immunochromatography assay (LAT) for the detection of rotavirus and coronavirus in faecal samples collected from diarrhoeic calves. DESIGN: Prospective survey. METHOD: Samples were tested at two separate facilities using a commercial ELISA and an in-house qRT-PCR. Simple logistic regression was performed to examine the relationship between the two tests. A subset of samples was screened using qRT-PCR, ELISA and a commercial LAT dipstick (132 faecal samples were tested for coronavirus and 122 samples for rotavirus). RESULTS: Of the 586 samples tested, 131 (22.39%) and 468 (79.86%) were positive for coronavirus and group A rotavirus, respectively, using qRT-PCR. The number of samples positive on ELISA for coronavirus and rotavirus was 73 (12.46%) and 225 (38.40%), respectively. Using LAT, 30 (22.73%) and 43 (35.35%) samples were positive for coronavirus and rotavirus, respectively. Simple linear regression revealed a statistically significant (P < 0.05) but weak (r(2) =-0.07 and -0.40) correlation between the rotavirus/coronavirus qRT-PCR and ELISA, respectively. There was also poor agreement between the LAT and qRT-PCR assays. CONCLUSION: The sensitivity and specificity of the commercial ELISA and LAT assays evaluated in this study were low compared with qRT-PCR. The low positive and negative predictive values of the assays suggests that they were of limited diagnostic benefit in the population sampled.


Subject(s)
Cattle Diseases/diagnosis , Coronavirus Infections/veterinary , Feces/virology , Rotavirus Infections/veterinary , Animals , Animals, Newborn , Australia , Cattle , Coronavirus/isolation & purification , Coronavirus Infections/diagnosis , Dairying , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Prospective Studies , Real-Time Polymerase Chain Reaction/veterinary , Reproducibility of Results , Rotavirus/isolation & purification , Rotavirus Infections/diagnosis , Sensitivity and Specificity
12.
Aust Vet J ; 89(5): 167-73, 2011 May.
Article in English | MEDLINE | ID: mdl-21495987

ABSTRACT

OBJECTIVE: Determine the prevalence of the major enteric pathogens in dairy and dairy beef calves with diarrhoea in Australia. DESIGN: Cross-sectional study. METHODS: Faecal samples from 84 Australian dairy and dairy beef properties (597 samples) were screened for rotavirus and coronavirus using real-time reverse transcription polymerase chain reaction, for Salmonella spp. using selective enrichment faecal culture, and for enterotoxigenic Escherichia coli (K99) and Cryptosporidium parvum using a commercial enzyme-linked immunosorbent assay. A logistic regression with random effects model was used to compare prevalence of pathogens in dairy and dairy beef operations. RESULTS: Enteric pathogens were isolated from 97.6% of outbreaks and 95.0% of samples. Rotavirus was the most common pathogen identified (477/597, 79.9%) followed by C. parvum (349/597, 58.5%), Salmonella spp. (142/597, 23.8%), coronavirus (129/597, 21.6%) and E. coli K99 (104/597, 17.4%). Multiple pathogens were identified on 96.4% of farms and from 71.0% of samples. Samples from dairy beef properties were more likely to have multiple pathogens than dairy properties (P < 0.05), whereas rotavirus and Salmonella spp. were more likely to be identified in samples collected from dairy beef than dairy properties (P < 0.05). CONCLUSION: Most outbreaks of calf diarrhoea in dairy and dairy beef operations involve multiple pathogens. Rotavirus and C. parvum were the most frequently identified pathogens across production systems. Salmonella spp. and rotavirus were more frequently identified in dairy beef operations.


Subject(s)
Cattle Diseases/epidemiology , Cattle Diseases/microbiology , Diarrhea/veterinary , Feces/microbiology , Animals , Animals, Newborn , Australia/epidemiology , Cattle , Cattle Diseases/virology , Coronavirus/isolation & purification , Cross-Sectional Studies , Cryptosporidium parvum/isolation & purification , Dairying , Diarrhea/epidemiology , Diarrhea/microbiology , Diarrhea/virology , Disease Outbreaks/veterinary , Feces/virology , Female , Logistic Models , Prevalence , Rotavirus/isolation & purification , Salmonella/isolation & purification
13.
Infez Med ; 19(4): 257-61, 2011 Dec.
Article in Italian | MEDLINE | ID: mdl-22212166

ABSTRACT

Chronic bacterial osteomyelitis requires long-term antibiotic treatment (at least 6-8 weeks). After in-hospital management, patients are usually discharged and treated in outpatient settings. However, when the aetiology is represented by Gram-negative microorganisms, outpatient treatment could be difficult. Beta-lactam administration by means of an elastomeric infusor may represent an attractive approach. We report two cases of osteomyelitis due to Pseudomonas aeruginosa successfully treated with continuous ceftazidime administration via an elastomeric infusor in outpatient settings. In both cases the patients were free from clinical and laboratory signs of osteomyelitis at the end of treatment and after 12 months follow-up.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Ceftazidime/therapeutic use , Diabetes Complications , Osteomyelitis/microbiology , Pseudomonas Infections/complications , Pseudomonas aeruginosa/drug effects , Chronic Disease , Diabetes Complications/drug therapy , Diabetes Complications/microbiology , Elastomers , Equipment Design , Follow-Up Studies , Humans , Infusion Pumps , Infusions, Parenteral/methods , Male , Middle Aged , Osteomyelitis/drug therapy , Outpatients , Pseudomonas Infections/drug therapy , Risk Factors , Treatment Outcome
14.
J Chem Phys ; 133(12): 124514, 2010 Sep 28.
Article in English | MEDLINE | ID: mdl-20886957

ABSTRACT

The high frequency dynamics of liquid iodine has been investigated by deep inelastic x-ray scattering at exchanged wave-vectors (q) ranging from 2.5 to 15 Å(-1). The experimental data have been analyzed in the frame of the Sachs-Teller theory of the molecular spectrum while accounting for final state corrections to the lineshape. The performed data analysis carries insights on physical quantities as relevant as the mean rototranslational kinetic energy and the mean square Laplacian of the intermolecular potential. In both cases the measured values are consistent with corresponding theoretical expectations.

15.
Aust Vet J ; 88(1-2): 45-51, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20148827

ABSTRACT

Several outbreaks of anaemia, jaundice, abortion and mortality in cattle in New South Wales were attributed to the intracellular parasite, Theileria buffeli. Disease occurred predominantly in periparturient animals that had been moved from inland to coastal areas. Diagnosis was made via exclusion of other causes of haemolytic anaemia and observation of the parasite in blood smears. Treatments included both registered and non-registered products. There is a possibility of a new strain of Theileria sp. in Australia and the possible vectors encountered in NSW are discussed.


Subject(s)
Anemia, Hemolytic/veterinary , Cattle Diseases/epidemiology , Theileriasis/epidemiology , Abortion, Veterinary/parasitology , Anemia, Hemolytic/epidemiology , Anemia, Hemolytic/etiology , Animals , Cattle , Disease Outbreaks/veterinary , Female , Male , New South Wales/epidemiology , Pregnancy , Pregnancy Complications, Parasitic/veterinary , Theileriasis/complications
16.
J Chem Phys ; 131(14): 144502, 2009 Oct 14.
Article in English | MEDLINE | ID: mdl-19831447

ABSTRACT

The density and temperature dependence of the structural relaxation time (tau) in water was determined by inelastic ultraviolet scattering spectroscopy in the thermodynamic range (P=1-4000 bars, T=253-323 K), where several water anomalies take place. We observed an activation (Arrhenius) temperature dependence of tau at constant density and a monotonic density decrease at constant temperature. The latter trend was accounted for by introducing a density-dependent activation entropy associated to water local structure. The combined temperature and density behavior of tau indicates that differently from previous results, in the probed thermodynamic range, the relaxation process is ruled by a density-dependent activation Helmholtz free energy rather than a simple activation energy. Finally, the extrapolation of the observed phenomenology at lower temperature suggests a substantial agreement with the liquid-liquid phase transition hypothesis.


Subject(s)
Elasticity , Scattering, Radiation , Temperature , Ultraviolet Rays , Water/chemistry , Spectrophotometry, Ultraviolet , Thermodynamics , Time Factors , X-Ray Diffraction
17.
Osteoarthritis Cartilage ; 10(1): 23-33, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11795980

ABSTRACT

OBJECTIVE: This study aims to apply gene expression profiling technology to gain insight into the molecular regulation of mesenchymal chondrogenesis. METHODS: The experimental system consists of micromass cultures of C3H10T1/2 cells, a murine multipotential embryonic cell line, treated with the chondroinductive growth factor, bone morphogenetic factor-2 (BMP-2). In this system, chondrogenic differentiation characterized by both morphological changes and cartilage matrix gene expression has been shown to be completely dependent upon BMP-2 treatment and the high cell plating density of micromass cultures. To identify candidate genes that may have key functional roles in chondrogenesis, we have applied subtractive hybridization to isolate genes whose expression is significantly up- or down-regulated during chondrogenesis. RNA was isolated from micromass cultures treated with BMP-2 for 24 h and analysed for representational differences by means of a subtractive hybridization screening method. RESULTS: Sixteen different genes were identified whose expression was up-regulated between two- and 12-fold by B,P-2, and twelve different genes were identified whose expression was down-regulated between two- and seven-fold by BMP-2. CONCLUSIONS: The potential of this screening methodology to identify new BMP-2 regulated genes is suggested by the fact that a majority of the identified genes are indeed novel. Identification and characterization of these genes should provide insight as to how chondrogenesis is regulated and also should provide important new markers for the study of osteoarthritis.


Subject(s)
Bone Morphogenetic Proteins/physiology , Cell Differentiation/physiology , Chondrocytes/cytology , Gene Expression Profiling , Transforming Growth Factor beta , Animals , Bone Morphogenetic Protein 2 , Down-Regulation , Mice , Nucleic Acid Hybridization , RNA/analysis , Reverse Transcriptase Polymerase Chain Reaction , Up-Regulation
18.
Rev. panam. flebol. linfol ; 41: 57-63, jun. 2001. tab
Article in Spanish | LILACS | ID: lil-299103

ABSTRACT

La pigmentación residual debido a un acto escleroterápico a lo largo de la várice y/o telangiectasia de los miembros inferiores, sea primaria o secundaria ("finissage") debido a una corrección quirúrgica, siempre representó un problema para el flebólogo y para el dermatólogo. Ese tipo de inestetismo, aunque temporario, no es aceptado por la paciente que, a veces, rehusa la misma escleroterapia o pasa a no creer en tal método, desaconsejándolo a sus amigas o conocidas. Actualmente, la imagen es cada vez más sinónimo de bienestar psíquico-físico, de allí la necesidad de contar con una flebología que sea "estética"; ello más que una exigencia es un deber para el flebólogo


Subject(s)
Humans , Adult , Female , Sclerosis , Sulfur , Varicose Veins , Skin Pigmentation , Lymphatic System
19.
Biochem Cell Biol ; 78(4): 477-85, 2000.
Article in English | MEDLINE | ID: mdl-11012087

ABSTRACT

ZF87/MAZ is a zinc finger transcription factor that activates expression of tissue-specific genes and represses expression of the c-myc proto-oncogene. Infection of NIH3T3 fibroblasts with a retrovirus expressing ZF87/MAZ leads to a significant reduction in G418-resistant colonies, compared to cells infected with a retroviral control. Further, only a small fraction of the G418-resistant colonies express ZF87/MAZ. When the ZF87/MAZ-expressing colonies are expanded, they demonstrate a slow growth phenotype, a delayed transit through G1 phase and a decrease in endogenous c-myc gene expression and cyclin A and cyclin E protein levels. Consistent with a partial G1 arrest, the ZF87/MAZ-expressing cells show a reduced sensitivity to the S phase specific chemotherapeutic agent camptothecin. These data indicate that ZF87/MAZ is a growth suppressor protein in nontransformed cells, in part, by affecting the levels of key cell cycle regulatory proteins.


Subject(s)
Cell Division , Transcription Factors/metabolism , Zinc Fingers , 3T3 Cells , Animals , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Camptothecin/pharmacology , Cell Division/drug effects , Culture Media , Cyclin A/genetics , Cyclin A/metabolism , Cyclin E/genetics , Cyclin E/metabolism , DNA-Binding Proteins , G1 Phase , Gene Expression , Genes, Reporter , Genes, myc/genetics , Gentamicins/pharmacology , Immunoblotting , Mice , Retroviridae/genetics , S Phase , Transcription Factors/genetics , Transfection
20.
J Infect Dis ; 182(4): 1109-16, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10979907

ABSTRACT

Disease caused by group A streptococci (GAS) in tropical regions often takes the form of impetigo, whereas pharyngitis tends to predominate in temperate zones. GAS derived from asymptomatic throat infections and pyoderma lesions of rural Aboriginal Australians were evaluated for phylogenetic distant emm genes, which represent ecological markers for tissue site preference. On the basis of the percentage of total isolates from a given tissue, emm pattern A-C organisms exhibited a stronger predilection for the throat, whereas pattern D organisms preferred the skin. Only 16% of isolates collected by active surveillance displayed pattern A-C, which reflects the low incidence of oropharyngeal infection. Importantly, most (70%) pattern A-C organisms were isolated from skin sores, despite their innate tendency to infect the throat. Combined with findings from nontropical populations, analysis of the data supports the hypothesis that GAS tissue preferences are genetically predetermined and that host risk factors for infection strongly influence the differential reproduction of individual clones.


Subject(s)
Antigens, Bacterial , Bacterial Outer Membrane Proteins , Pharyngitis/epidemiology , Pharyngitis/microbiology , Skin Diseases, Bacterial/epidemiology , Streptococcal Infections/epidemiology , Streptococcus pyogenes/genetics , Adult , Australia/epidemiology , Bacterial Proteins/genetics , Carrier Proteins/genetics , Carrier State/epidemiology , Carrier State/microbiology , Child , Humans , Impetigo/epidemiology , Impetigo/microbiology , Molecular Epidemiology , Native Hawaiian or Other Pacific Islander , Phylogeny , Pyoderma/epidemiology , Pyoderma/microbiology , Rural Population , Streptococcus pyogenes/isolation & purification , Tropical Climate
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