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1.
Artículo en Inglés | MEDLINE | ID: mdl-36874189

RESUMEN

Background: Asthma medication prescription trends, including those of short-acting ß2 -agonists (SABAs), are not well documented for South Africa (SA). Objectives: To describe demographics, disease characteristics and asthma prescription patterns in the SA cohort of the SABA use IN Asthma (SABINA) III study. Methods: An observational, cross-sectional study conducted at 12 sites across SA. Patients with asthma (aged ≥12 years) were classified by investigator-defined asthma severity, guided by the Global Initiative for Asthma (GINA) 2017 recommendations, and practice type (primary/ specialist care). Data were collected using electronic case report forms. Results: Overall, 501 patients were analysed - mean (standard deviation) age, 48.4 (16.6) years; 68.3% female - of whom 70.6% and 29.4% were enrolled by primary care physicians and specialists, respectively. Most patients were classified with moderate-to-severe asthma (55.7%; GINA treatment steps 3 - 5), were overweight or obese (70.7%) and reported full healthcare reimbursement (55.5%). Asthma was partly controlled/uncontrolled in 60.3% of patients, with 46.1% experiencing ≥1 severe exacerbations in the 12 months before the study visit. Overall, 74.9% of patients were prescribed ≥3 SABA canisters in the previous 12 months (over-prescription); 56.5% were prescribed ≥10 SABA canisters. Additionally, 27.1% of patients reported purchasing SABA over-the-counter (OTC); among patients with both SABA purchase and prescriptions, 75.4% and 51.5% already received prescriptions for ≥3 and ≥10 SABA canisters, respectively, in the preceding 12 months. Conclusion: SABA over-prescription and OTC purchase were common in SA, demonstrating an urgent need to align clinical practices with the latest evidence-based recommendations and regulate SABA OTC purchase to improve asthma outcomes. Study synopsis: What the study adds. This study provides valuable insights into asthma medication prescription patterns, particularly SABAs, across SA. Collection of this real-world data in patients treated in primary and specialty care demonstrates that SABA over-prescription and SABA OTC purchase are common, even in patients with mild asthma. These findings will enable clinicians and policymakers to make targeted changes to optimise asthma outcomes across the country Implications of the findings. SABA over-prescription represents a major public health concern in SA. Healthcare providers and policymakers will need to work together to promote educational initiatives aimed at patients, pharmacists and physicians, align clinical practices with the latest evidence-based recommendations, improve access to affordable medications and regulate SABA purchase without prescription.

2.
FEBS Lett ; 581(22): 4309-17, 2007 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-17716670

RESUMEN

The GTPase RhoA is essential for the development of pre-T cells in the thymus. To investigate the mechanisms used by RhoA to control thymocyte development we have used Affymetrix gene profiling to identify RhoA regulated genes in T cell progenitors. The data show that RhoA plays a specific and essential role in pre-T cells because it is required for the expression of transcription factors of the Egr-1 and AP-1 families that have critical functions in thymocyte development. Loss of RhoA function in T cell progenitors causes a developmental block that pheno-copies the consequence of losing pre-TCR expression in Recombinase gene 2 (Rag2) null mice. Transcriptional profiling reveals both common and unique gene targets for RhoA and the pre-TCR indicating that RhoA participates in the pre-TCR induced transcriptional program but also mediates pre-TCR independent gene transcription.


Asunto(s)
Células Madre/metabolismo , Linfocitos T/metabolismo , Transcripción Genética , Proteína de Unión al GTP rhoA/metabolismo , ADP Ribosa Transferasas/metabolismo , Animales , Biomarcadores/metabolismo , Toxinas Botulínicas/metabolismo , Perfilación de la Expresión Génica , Ratones , Ratones Endogámicos C57BL , Fosforilación , Receptores de Antígenos de Linfocitos T/metabolismo , Proteína S6 Ribosómica/metabolismo , Células Madre/enzimología , Linfocitos T/enzimología , Timo/enzimología , Regulación hacia Arriba/genética
3.
Int J Oncol ; 7(5): 1185-91, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21552950

RESUMEN

The Drosophila ras2 and rop gene pair are governed by a common promoter. Characterisation of the Drosophila ras2/rop bidirectional promoter has revealed that a single major protein complex (M), composed of two subunits (factors A and B) interacts with two central promoter domains (regions A and B). To define the transcriptional control elements contained within region A (-58 to -39) we performed mutational analysis on several putative elements. This approach has revealed that the conserved TATA-like, SRE-like and GATA-like sequences do not interact with factor A and are not regulatory elements of this promoter. Nucleotides -56 to -49 bear perfect homology to the Drosophila DNA replication-related element (DRE, TATCGATA) found in two genes involved in DNA replication and cell proliferation, the Drosophila proliferating cell nuclear antigen (PCNA) and DNA polymerase a. A CG pair (-53 and -52) has been pinpointed as cardinal for factor A binding. Factor A has been partially purified and identified as a 20 kDa polypeptide by photo-chemical crosslinking analysis.

4.
Int J Oncol ; 7(5): 1193-201, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21552951

RESUMEN

The Drosophila ras2 promoter is an authentic bidirectional promoter governing the expression of both the Dras2 and rop genes by a single mechanism. Characterisation of the Dras2/rop promoter has revealed that a unitary complex (M) interacts with two promoter sub-domains (regions A and B). Two distinct transcription factors (factors A and B),which make up the major complex (M), bind regions A and B, respectively. We have analyzed the putative CACCC element and AP-1-Iike sequence contained within region B (-41 to -20) of the Dras2/rop promoter. It was found that AP-1 is not involved in Dras2 expression as is the case for the human Ha-ras1 gene. The entire CACCC motif (-34 to -21) shares 83% homology with the conserved mammalian element. Detailed mutational analysis has however revealed that the CACCC core sequence (-27 to -23) is vital for Dras2/rop recognition by factor B. The cytosine residues at positions -27, -25, -24 and -23 were observed to play a critical role in factor B recognition. Factor B has been purified as a 43 kD polypeptide as measured by SDS-PAGE and the relative mass was confirmed by photo-chemical crosslinking. Our findings are the first report of the conservation of the mammalian CACCC motif in Drosophila.

5.
J Invest Surg ; 13(6): 349-58, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11202012

RESUMEN

The goal was to develop a clinically relevant animal model that could be used to assess the efficacy of therapeutic interventions in lung cancer. Two cell lines, noncancerous control (BEAS2-B, immortalized human bronchial-epithelial cell line) and cancerous (BZR-T33, H-ras transformed BEAS2-B) were implanted into nude (athymic) mice. Two groups (n = 10 each) received dorsoscapular subcutaneous injection of 10(6) cells from either cell line. BEAS2-B cells were nontumorigenic, whereas mice with BZR-T33 cells had tumors (9,510 +/- 4,307 mm3) confirmed by histology, and a significantly smaller body weight (BZR-T33, 28.5 +/- 0.49 vs. BEAS2-B, 30.7 +/- 0.75 g, p < .05). The next phase evaluated invasion/metastasis. Two groups (n = 10 each) received 10(6) cells from either cell line injected into tail veins. Animals receiving BZR-T33 cells had a smaller body weight, palpable lung masses (67%), obvious tail masses (44%), and average tumor burden (1,120 +/- 115 mm3), and histology revealed invasion of lung tissue and interstitial hemorrhage. In development of the orthotopic xenotransplanted model, mice (2 groups, n = 10 each) received 10(6) cells from either cell line implanted into the lungs through a tracheotomy. Animals with BZR-T33 cells did not survive past 59 days and had a smaller body weight, increased lung weight, lung masses (100%), and metastatic loci (30%). Magnetic resonance imaging (MRI) confirmed the presence of masses in intubated live mice, later confirmed by histology. In summary, the H-ras transfected cell line developed lung masses following tail-vein injection and endotracheal seeding. Evaluation by MRI allows for a comprehensive model with significant potential in the study of lung cancer.


Asunto(s)
Neoplasias Pulmonares/cirugía , Trasplante de Neoplasias/métodos , Trasplante Heterólogo/métodos , Animales , Bronquios/citología , Pruebas de Carcinogenicidad , Línea Celular Transformada/trasplante , Modelos Animales de Enfermedad , Femenino , Hemorragia/patología , Humanos , Neoplasias Pulmonares/secundario , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Desnudos , Invasividad Neoplásica
6.
Theriogenology ; 42(6): 895-907, 1994 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-16727595

RESUMEN

In Experiments 1 and 2, ultrasound-guided transvaginal follicle aspiration was used as a method of follicle ablation to induce and synchronize subsequent follicular wave emergence and enhance ovulation synchrony following PGF2alpha administration. Heifers were at unknown stages of the estrous cycle at the start of both experiments in which all follicles>or=5 mm in diameter were ablated; luteolysis was induced 4 d later with cloprostenol (500 ug/dose, im). In Experiment 1, heifers were randomly assigned to either an ablation (n=17) or a procedural control (no follicle ablation, n=17) group. Ablation-induced wave emergence was indicated by a significant increase in the total number of follicles>or=5 mm within 2 d of ablation (mean, 1.5 d), which was preceded by a significant surge in circulating FSH. Although the mean (+/-SEM) interval from PGF2alpha administration to ovulation did not differ between follicle-ablated heifers (5.1+/-0.5 d range, 3 to 9 d) and control heifers (5.1+/-1.0 d; range, 1 to 5 d), the variability of the interval was different (P<0.05). Inequality of variance between the 2 groups was attributed to a greater (P<0.08) degree of ovulation synchrony in the ablation group than in the control group; 13/16 (81%) versus 9/17 (53%), respectively, ovulated within 5 d of cloprostenol administration. Relative asynchrony of ovulations in control heifers was associated with the status of the follicular wave at the time of PGF2alpha administration and, in part, to incomplete luteolysis following a single dose of PGF2alpha. Experiment 2 was designed to examine the efficacy of 2 doses of cloprostenol 12 h apart (n=7) versus a single dose (n=8) to induce complete luteolysis subsequent to follicle ablation-induced wave emergence. Two doses of cloprostenol potentiated ovulation synchrony; more (P<0.05) 2-dose heifers (7/7, 100%) than single-dose heifers (4/8, 50%) ovulated within 5 d after PGF2alpha administration. In summary, ultrasound-guided transvaginal follicle ablation, done at random during the estrous cycle, induced and synchronized subsequent follicular wave emergence, and resulted in a high degree of ovulation synchrony among heifers after PGF2alpha induced luteolysis, especially when 2 doses of PGF2alpha were administered 12 h apart.

7.
Equine Vet J ; 31(2): 153-9, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10213428

RESUMEN

Historical, clinical and experimental data were collected from 9 horses homozygous for HYPP (H/H). All showed episodes of respiratory stertor, described as a rattling or honking sound, usually within the first week post partum. Five horses had one or more episodes of dysphagia, in 3 horses this was accompanied by drooling and in 3 by weight loss. In comparison, only one of 35 contemporaneous half siblings (of which approximately half would be expected to be of the H/N genotype and half N/N) was observed to have respiratory stertor prior to weaning and none had problems with dysphagia. One mature homozygous stallion was infertile secondary to urospermia. Six homozygous horses died or were subjected to euthanasia; 4 age less than a year, one age 20 months and one age 5 years. The remaining 3 cases were still alive at the end of the study. A comparison of homozygous and heterozygous horses using standardised potassium chloride challenge testing indicated that during attacks homozygotes showed significantly more frequent signs of drooling, prolapse of the third eyelid, respiratory stridor and weakness than heterozygous horses. Homozygotes also had significantly more total abnormalities (including myotonic discharges, high frequency repetitive discharges, and spontaneous activity) on electromyographic examination than heterozygotes. These data imply that HYPP is inherited as a codominant genetic defect, because the homozygotes showed more severe clinical signs of disease than heterozygotes. Homozygous foals would be expected to be produced in 25% of matings in which both parents are heterozygous. Owners and veterinarians should be aware of the risks of this mating.


Asunto(s)
Enfermedades de los Caballos/genética , Hiperpotasemia/veterinaria , Parálisis/veterinaria , Animales , Trastornos de Deglución/genética , Trastornos de Deglución/veterinaria , Electromiografía/veterinaria , Femenino , Genotipo , Heterocigoto , Homocigoto , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Caballos/fisiopatología , Caballos , Hiperpotasemia/diagnóstico , Hiperpotasemia/genética , Masculino , Parálisis/genética , Cloruro de Potasio , Ruidos Respiratorios/veterinaria
8.
Br J Cancer ; 69(2): 264-73, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8297724

RESUMEN

The Drosophila ras2 promoter region exhibits bidirectional activity, as has been demonstrated for the human c-Ha-ras1 and the mouse c-Ki-ras. Here we address a unique case of ras regulation, as Drosophila ras2 provides the only example to date in which the flanking gene (rop) and its product have been isolated. A linking mechanism of control suggests a mutual interaction between the two gene products. Our studies indicate that the Drosophila ras2 promoter region shares with the human c-Ha-ras1 promoter a CACCC box and an AP-1-like sequence. A 14 bp promoter fragment which holds a CACCC element is demonstrated to interact with a specific transcription factor (factor B). This CACCC promoter element represents a stretch of imperfect palindrome. We present evidence that this factor can form a complex with another specific DNA-binding protein (factor A). The binding sites (A + B) for these protein factors are essential for 95% expression of both genes flanking the promoter (ras2 and rop). Region A consists of four overlapping consensus sequences: a TATA-like element, a DSE-like motif (the core sequence of the serum response element), a DRE octamer, which has been shown to play a role in cell proliferation, and a 5 bp direct repeat representing the GATA consensus sequence. Factor A has a very weak affinity to the full promoter region, but when complexed with factor B binding efficiency is enhanced. We also show that alterations of DNA-protein binding specificities can be achieved by supplementing the growth media with different sera.


Asunto(s)
Secuencia Conservada/genética , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica/genética , Genes ras/genética , Regiones Promotoras Genéticas/fisiología , Animales , Secuencia de Bases , Proteínas de Unión al ADN/fisiología , Drosophila/genética , Datos de Secuencia Molecular , Transcripción Genética
9.
Biol Bull ; 181(2): 307-311, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29304623

RESUMEN

Thin sections of a compact, internal structure projecting from the hinge region of the bivalve Mya arenaria reveal the presence of tidal and seasonal patterns. This is the first demonstration that microgrowth increments are formed in a stucture not associated with the growing edge of the shell. The clarity and simple orientation of these extensive patterns, combined with the hinge region to disturbance and damage, suggests that detailed examinations of internal shell structures will prove valuable in ecological, archaeological, and paleoecological studies.

10.
Hepatology ; 26(3): 740-2, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9303506

RESUMEN

The newly cloned and characterized hepatitis GB virus-C (HGBV-C), which is the same virus as the independently discovered hepatitis G virus, has a global distribution, is transmitted parenterally, and causes chronic viremia. The pathological consequences of infection with HGBV-C are uncertain, and its hepatocarcinogenic potential is unknown. We used a case-control format to compare the prevalence of HGBV-C infection in 167 southern African blacks with hepatocellular carcinoma (HCC) and 167 race-, age-, and sex-matched hospital-based control subjects, and to test for possible interactive effects between this virus and hepatitis B and C viruses in the development of the tumor. The presence of HGBV-C ribonucleic acid was detected in serum samples by reverse transcription, amplification of the resulting complementary deoxyribonucleic acid by the polymerase chain reaction (PCR), and Southern hybridization using a probe from the NS3/helicase region of the genome. Serum samples were also tested for the presence of hepatitis B virus surface antigen, antibodies to hepatitis C virus, and hepatitis C virus ribonucleic acid. Individuals infected with HGBV-C did not have an increased relative risk of developing HCC (relative risk 0.9; 95% confidence limits 0.5, 1.7). Moreover, co-infection with HGBV-C did not further increase the risk of tumor development in patients who were chronically infected with hepatitis B and/or C viruses. HGBV-C is unrelated to hepatocellular carcinoma development in black Africans.


Asunto(s)
Población Negra , Carcinoma Hepatocelular/epidemiología , Flaviviridae , Hepatitis Viral Humana/complicaciones , Neoplasias Hepáticas/epidemiología , Negro o Afroamericano , Carcinoma Hepatocelular/virología , Estudios de Casos y Controles , Intervalos de Confianza , ADN Viral/sangre , Etnicidad , Femenino , Flaviviridae/aislamiento & purificación , Hepatitis B/complicaciones , Hepatitis C/complicaciones , Humanos , Neoplasias Hepáticas/virología , Masculino , Reacción en Cadena de la Polimerasa , ARN Viral/sangre , Medición de Riesgo , Factores de Riesgo , Sudáfrica
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