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1.
Front Physiol ; 13: 772313, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35464086

RESUMEN

Mitochondrial malfunction is a hallmark of many diseases, including neurodegenerative disorders, cardiovascular and lung diseases, and cancers. We previously found that alveolar progenitor cells, which are more resistant to cigarette smoke-induced injury than the other cells of the lung parenchyma, upregulate the mtDNA-encoded small non-coding RNA mito-ncR-805 after exposure to smoke. The mito-ncR-805 acts as a retrograde signal between the mitochondria and the nucleus. Here, we identified a region of mito-ncR-805 that is conserved in the mammalian mitochondrial genomes and generated shorter versions of mouse and human transcripts (mmu-CR805 and hsa-LDL1, respectively), which differ in a few nucleotides and which we refer to as the "functional bit". Overexpression of mouse and human functional bits in either the mouse or the human lung epithelial cells led to an increase in the activity of the Krebs cycle and oxidative phosphorylation, stabilized the mitochondrial potential, conferred faster cell division, and lowered the levels of proapoptotic pseudokinase, TRIB3. Both oligos, mmu-CR805 and hsa-LDL1 conferred cross-species beneficial effects. Our data indicate a high degree of evolutionary conservation of retrograde signaling via a functional bit of the D-loop transcript, mito-ncR-805, in the mammals. This emphasizes the importance of the pathway and suggests a potential to develop this functional bit into a therapeutic agent that enhances mitochondrial bioenergetics.

2.
Am Surg ; 86(8): 1005-1009, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32997953

RESUMEN

INTRODUCTION: Interteam performance and Clavien-Dindo (C-D) complications in renal cell carcinoma with inferior vena cava thrombectomy (RCC-IVCT) have not been reported. We aimed to describe complications by the degree of complexity and surgical teams in a collaborative effort between a National Cancer Institute-designated Comprehensive Cancer Center and a Quaternary Care Teaching Hospital. METHODS: Between January 2011 and May 2019, 73 consecutive RCC-IVCT were included. C-D grades III or higher were captured. Teams involved were urologic-oncology, vascular, hepatobiliary/transplant, and cardiothoracic. The Mayo Clinic tumor thrombus classification was used. RESULTS: Overall complication rate was 42% (n = 31). Nineteen percent had grade III, 18% had grade IV, and 6% had grade V complications. Patients with level IV thrombus had the highest in-hospital mortality rate (75%). Thrombus level did not show a correlation to complication rates (14% level I, 45% level II, 32% level III, 42% level IV). A positive correlation found between the number of teams involved and complication rates (35% with 2-team, 59% with 3-team, P = .059). Thromboembolic events (6% vs 24%, P = .02) and disposition other than home (22% vs 48%, P = .01) were statistically lower for the 2-team groups. Two-team in-hospital mortality was 1/51 (2%) versus 3-team (3/22,14%, (P = .07). No statistical differences were found in infections, thromboembolic events, and grades of complications between surgical teams. CONCLUSIONS: Despite similar interteam performance, the consistency of surgeons in high complexity cases could improve outcomes further. Complexity was higher for hepatobiliary/transplant and cardiothoracic teams. A combination of intraoperative events and patient selection (comorbidities and age) contributed to death. Overall, in-hospital mortality was lower than in most reported series.


Asunto(s)
Carcinoma de Células Renales/complicaciones , Neoplasias Renales/complicaciones , Grupo de Atención al Paciente , Trombectomía , Vena Cava Inferior/cirugía , Trombosis de la Vena/cirugía , Adulto , Anciano , Instituciones Oncológicas , Florida , Mortalidad Hospitalaria , Hospitales de Enseñanza , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos , Resultado del Tratamiento , Trombosis de la Vena/etiología
3.
Can J Urol ; 27(1): 10118-10124, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32065869

RESUMEN

INTRODUCTION: To describe the incidence, contemporary management, risk factors and outcomes of urinary leak following open and robotic partial nephrectomy at a tertiary care, comprehensive cancer center. MATERIALS AND METHODS: We reviewed 975 patients who underwent partial nephrectomy at Moffitt Cancer Center from January 2009 to May 2017. Patient demographic, perioperative and follow up data was recorded and compared stratified for postoperative urine leak. Fisher's exact and Wilcoxon sum-rank testing were performed for categorical and continuous variables as indicated. RESULTS: Twenty-three of 975 (2.3%) patients experienced a urine leak after partial nephrectomy. Median nephrometry score for urine leak patients was 8 (SD +/- 1.3). Median postoperative days to detection was 3.5 and most leaks were discovered due to high drain output. Operative factors associated with urinary leak included open surgery, estimated blood loss, and not using a sliding-clip renorrhaphy (p < 0.05). Ten (44%) were managed conservatively, 9 (39%) patients required ureteral stent placement, 3 (13%) needed a percutaneous nephrostomy tube, one patient (4%) required percutaneous drainage for urinoma (4%). One patient ultimately failed conservative management and required nephrectomy 45 days after the original surgery. Mean time to stent and drain removal was 40 +/- 17 and 24 +/- 7 days, respectively. Five patients with symptomatic leaks were readmitted with a mean length of stay of 3.2 +/- 1.8 days. CONCLUSIONS: The overall incidence of urinary leak after partial nephrectomy remains low regardless of surgical approach. Perioperative characteristics such as tumor complexity and high blood loss, in addition to open surgery and not using a sliding-clip bolstered renorrhaphy are associated with urine leak.


Asunto(s)
Neoplasias Renales/cirugía , Nefrectomía/métodos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/cirugía , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Nefrectomía/efectos adversos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Riesgo , Procedimientos Quirúrgicos Robotizados , Incontinencia Urinaria/etiología
4.
World J Surg ; 42(9): 2701-2707, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29750321

RESUMEN

INTRODUCTION: Although enhanced recovery after surgery (ERAS) components include both anesthesia and surgical care processes, it is unclear whether a multidisciplinary approach to implementing ERAS care processes improves clinical outcomes. The addition of multidisciplinary care with anesthesiology-related components to an existing ERAS protocol for radical cystectomy at a US comprehensive cancer center provided an opportunity to compare short- and long-term outcomes. METHODS: We retrospectively compared the outcomes of 116 consecutive patients who underwent cystectomy after implementation of a multidisciplinary ERAS protocol with those of a historical control group of 143 consecutive patients who had been treated with a surgical ERAS protocol. Length of stay, return of bowel function, rate of blood transfusion, nausea, pain, and readmission rates were examined. RESULTS: Implementation of a multidisciplinary ERAS protocol was associated with better postsurgical symptom control, as indicated by lower rates of patient-reported nausea (P < .05). Multivariate Poisson regression analysis showed a decrease in estimated intraoperative transfusions (P ≤ .001) after adjusting for the effects of potential confounding variables. There were no statistically significant differences noted in length of stay, return of bowel function, 30- and 90-day complications, or readmissions. CONCLUSION: This is the first study to investigate the effects of adding anesthesia ERAS components to an existing surgical ERAS protocol for radical cystectomy. We found that with the addition of anesthesia-related interventions, there was a decrease in transfusions and nausea.


Asunto(s)
Instituciones Oncológicas , Protocolos Clínicos , Cistectomía , Atención Perioperativa , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Grupo de Atención al Paciente , Estudios Retrospectivos , Resultado del Tratamiento , Estados Unidos
5.
Arch Environ Contam Toxicol ; 74(3): 414-430, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28687868

RESUMEN

Chemical dispersants can be a useful tool to mitigate oil spills. This study examined potential risks to sensitive estuarine species by comparing the toxicity of two dispersants (Corexit® EC9500A and Finasol® OSR 52) individually and in chemically enhanced water-accommodated fractions (CEWAFs) of Louisiana Sweet Crude oil. Acute toxicity thresholds and sublethal biomarker responses were determined in seven species (sheepshead minnow, grass shrimp, mysid, amphipod, polychaete, hard clam, mud snail). Comparing median lethal (LC50) values for the dispersants, Finasol was generally more toxic than Corexit and had greater sublethal toxicity (impaired embryonic hatching, increased lipid peroxidation, decreased acetylcholinesterase activity). The nominal concentration-based mean LC50 for all species tested with Corexit was 150.31 mg/L compared with 43.27 mg/L with Finasol. Comparing the toxicity of the CEWAFs using the nominal concentrations (% CEWAF), Corexit-CEWAFs appeared more toxic than Finasol-CEWAFs; however, when LC50 values were calculated using measured hydrocarbon concentrations, the Finasol-CEWAFs were more toxic. There was greater dispersion efficiency leading to greater hydrocarbon concentrations measured in the Corexit-CEWAF solutions than in equivalent Finasol-CEWAF solutions. The measured concentration-based mean LC50 values for all species tested with Corexit-CEWAF were 261.96 mg/L total extractable hydrocarbons (TEH) and 2.95 mg/L total polycyclic aromatic hydrocarbons (PAH), whereas the mean LC50 values for all species tested with Finasol-CEWAF were 23.19 mg/L TEH and 0.49 mg/L total PAH. Larval life stages were generally more sensitive to dispersants and dispersed oil than adult life stages within a species. These results will help to inform management decisions regarding the use of oil-spill dispersants.


Asunto(s)
Ecotoxicología/métodos , Contaminantes Químicos del Agua/toxicidad , Anfípodos/efectos de los fármacos , Animales , Crustáceos/efectos de los fármacos , Cyprinidae/embriología , Embrión no Mamífero , Estuarios , Larva , Louisiana , Compuestos Orgánicos/toxicidad , Petróleo , Contaminación por Petróleo , Hidrocarburos Policíclicos Aromáticos/toxicidad , Caracoles/efectos de los fármacos , Pruebas de Toxicidad/métodos
6.
Urology ; 93: 130-4, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27041469

RESUMEN

OBJECTIVE: To evaluate the incidence and degree of change from a pathologic second opinion of bladder biopsies at a Comprehensive Cancer Center that were initially performed at referring community hospitals. The secondary objective was to determine the impact the potential changes would have on a patient's treatment. MATERIALS AND METHODS: Dedicated genitourinary pathologists reviewed 1191 transurethral biopsies of the bladder and/or prostatic urethra from 2008 to 2013. Major and minor treatment changes were defined as altering recommendations for cystectomy, systemic chemotherapy, or primary cancer diagnosis, and alterations in intravesical regimens, respectively. RESULTS: There were 326/1191 patients (27.4%) with a pathologic change on second opinion: grade (62/1191, 5.2%), stage (115/1191, 9.7%), muscle in the specimen (29/1191, 2.4%), presence or absence of carcinoma in situ (34/1191, 2.9%). Outside pathology did not address the presence or absence of lymphovascular invasion in 620/759 (81.7%) of invasive cases (≥cT1), of which 35/620 (5.6%) had lymphovascular invasion. There were 212 mixed, variant, or nonurothelial histologies detected in 199/1191 (16.7%) patients, with 114/212 (53.7%) resulting in reclassification by our pathologists. Potential treatment alterations accounted for 182/1191 (15.3%) of cases, with 141/1191 (11.8%) imparting major changes. There were 82/1191 (6.8%) changes in recommendation for a radical cystectomy, 38/1191 (3.2%) had a complete change in primary tumor type, and 21/1191 (1.8%) for change in chemotherapy regimen. CONCLUSION: The amount and degree of pathologic changes and its potential impact on treatment emphasize the importance of bladder cancer patients having their histology reviewed by genitourinary-dedicated pathologists. In our cohort, 15.3% of patients could see a treatment alteration, with 11.8% being a major change.


Asunto(s)
Toma de Decisiones Clínicas , Derivación y Consulta , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/terapia , Instituciones Oncológicas , Humanos
7.
Lancet ; 387(10032): 2008-16, 2016 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-26969090

RESUMEN

BACKGROUND: Renal-cell carcinoma is highly vascular, and proliferates primarily through dysregulation of the vascular endothelial growth factor (VEGF) pathway. We tested sunitinib and sorafenib, two oral anti-angiogenic agents that are effective in advanced renal-cell carcinoma, in patients with resected local disease at high risk for recurrence. METHODS: In this double-blind, placebo-controlled, randomised, phase 3 trial, we enrolled patients at 226 study centres in the USA and Canada. Eligible patients had pathological stage high-grade T1b or greater with completely resected non-metastatic renal-cell carcinoma and adequate cardiac, renal, and hepatic function. Patients were stratified by recurrence risk, histology, Eastern Cooperative Oncology Group (ECOG) performance status, and surgical approach, and computerised double-blind randomisation was done centrally with permuted blocks. Patients were randomly assigned (1:1:1) to receive 54 weeks of sunitinib 50 mg per day orally throughout the first 4 weeks of each 6 week cycle, sorafenib 400 mg twice per day orally throughout each cycle, or placebo. Placebo could be sunitinib placebo given continuously for 4 weeks of every 6 week cycle or sorafenib placebo given twice per day throughout the study. The primary objective was to compare disease-free survival between each experimental group and placebo in the intention-to-treat population. All treated patients with at least one follow-up assessment were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT00326898. FINDINGS: Between April 24, 2006, and Sept 1, 2010, 1943 patients from the National Clinical Trials Network were randomly assigned to sunitinib (n=647), sorafenib (n=649), or placebo (n=647). Following high rates of toxicity-related discontinuation after 1323 patients had enrolled (treatment discontinued by 193 [44%] of 438 patients on sunitinib, 199 [45%] of 441 patients on sorafenib), the starting dose of each drug was reduced and then individually titrated up to the original full doses. On Oct 16, 2014, because of low conditional power for the primary endpoint, the ECOG-ACRIN Data Safety Monitoring Committee recommended that blinded follow-up cease and the results be released. The primary analysis showed no significant differences in disease-free survival. Median disease-free survival was 5·8 years (IQR 1·6-8·2) for sunitinib (hazard ratio [HR] 1·02, 97·5% CI 0·85-1·23, p=0·8038), 6·1 years (IQR 1·7-not estimable [NE]) for sorafenib (HR 0·97, 97·5% CI 0·80-1·17, p=0·7184), and 6·6 years (IQR 1·5-NE) for placebo. The most common grade 3 or worse adverse events were hypertension (105 [17%] patients on sunitinib and 102 [16%] patients on sorafenib), hand-foot syndrome (94 [15%] patients on sunitinib and 208 [33%] patients on sorafenib), rash (15 [2%] patients on sunitinib and 95 [15%] patients on sorafenib), and fatigue 110 [18%] patients on sunitinib [corrected]. There were five deaths related to treatment or occurring within 30 days of the end of treatment; one patient receiving sorafenib died from infectious colitis while on treatment and four patients receiving sunitinib died, with one death due to each of neurological sequelae, sequelae of gastric perforation, pulmonary embolus, and disease progression. Revised dosing still resulted in high toxicity. INTERPRETATION: Adjuvant treatment with the VEGF receptor tyrosine kinase inhibitors sorafenib or sunitinib showed no survival benefit relative to placebo in a definitive phase 3 study. Furthermore, substantial treatment discontinuation occurred because of excessive toxicity, despite dose reductions. These results provide a strong rationale against the use of these drugs for high-risk kidney cancer in the adjuvant setting and suggest that the biology of cancer recurrence might be independent of angiogenesis. FUNDING: US National Cancer Institute and ECOG-ACRIN Cancer Research Group, Pfizer, and Bayer.


Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma de Células Renales/tratamiento farmacológico , Indoles/administración & dosificación , Neoplasias Renales/tratamiento farmacológico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Pirroles/administración & dosificación , Administración Oral , Antineoplásicos/efectos adversos , Carcinoma de Células Renales/mortalidad , Quimioterapia Adyuvante/mortalidad , Supervivencia sin Enfermedad , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Indoles/efectos adversos , Neoplasias Renales/mortalidad , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/efectos adversos , Compuestos de Fenilurea/efectos adversos , Pirroles/efectos adversos , Sorafenib , Sunitinib , Resultado del Tratamiento
8.
J Agric Food Chem ; 63(48): 10355-65, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26550846

RESUMEN

Widespread infection of Epichloë occultans in annual ryegrass in Australia suggests that infection provides its weedy host, Lolium rigidum, some ecological advantage. Initial studies determined the distribution and profiles of known Epichloë alkaloids (epoxy-janthitrems, ergovaline, lolines, lolitrem B, and peramine) in plant extracts using a combination of GC-FID and HPLC techniques utilizing a single accession of Australian L. rigidum. However, the lolines N-acetylnorloline (NANL) and N-formylloline (NFL) were the only alkaloids detected and were highly concentrated in the immature inflorescences of mature plants. Additional glasshouse studies subjected a wide range of Australian L. rigidum haplotypes and international annual Lolium accessions to a suite of analyses to determine alkaloid levels and profiles. Again, NFL and NANL were the key lolines produced, with NFL consistently predominating. Considerable variation in alkaloid production was found both within and between biotypes and accessions evaluated under identical conditions, at the same maturation stage and on the same tissue type. The pyrrolopyrazine alkaloid peramine was also present in 8 out of 17 Australian biotypes of L. rigidum and 7 out of 33 international accessions infected with Epichloë spp.; the highest peramine concentrations were observed in seed extracts from L. rigidum collected from Australia. This study represents the first report of alkaloids from a geographically diverse collection of annual ryegrass germplasm infected with Epichloë spp. when grown under identical controlled conditions.


Asunto(s)
Alcaloides/análisis , Epichloe/fisiología , Lolium/química , Lolium/microbiología , Enfermedades de las Plantas/microbiología , Alcaloides/metabolismo , Australia , Lolium/genética , Lolium/metabolismo , Enfermedades de las Plantas/genética
9.
Neuroscience ; 160(3): 577-86, 2009 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-19272420

RESUMEN

Steroid hormones, especially estradiol, facilitate reproductive behaviors in male and female rodents and birds. In green anole lizards estradiol facilitates receptivity in females but, unlike in some other species, is not the activating hormone for courtship and copulatory behavior in males. Instead, testicular androgens directly facilitate male courtship and copulation. Yet, activity of the estradiol synthesizing enzyme aromatase is higher in the brain of male than female green anoles, and it is increased during the breeding compared to the non-breeding season. The functional relevance of these differences in local estradiol production is unknown. They might prime the male forebrain to facilitate production of appropriate sexual behaviors, perhaps by modifying morphology of relevant brain regions. In addition, we recently reported increased expression of estrogen receptor alpha (ERalpha) in selected brain regions in females compared to males [Beck LA, Wade J (2009b) Sexually dimorphic estrogen receptor alpha mRNA expression in the preoptic area and ventromedial hypothalamus of green anole lizards. 55:398-403]. Thus, it is possible that the hormone serves to downregulate its receptor in males to inhibit the expression of estradiol-dependent receptive behaviors. To begin to address these ideas, the present study examines the effects of estradiol treatment, sex, and season on forebrain morphology and ERalpha mRNA abundance in three regions important for anole reproductive behavior-the preoptic area, ventromedial amygdala, and ventromedial hypothalamus. While a number of effects of sex and season on forebrain morphology were detected, direct effects of estradiol treatment on these measures were minimal. ERalpha expression was greatest in the ventromedial hypothalamus, and a large female-biased sex difference was detected in this area alone; it resulted from estradiol-treated animals. These results indicate a sex- and region-specific mechanism by which estradiol can modify ERalpha expression in the green anole and could impact the expression of female-typical receptivity.


Asunto(s)
Estradiol/metabolismo , Receptor alfa de Estrógeno/metabolismo , Lagartos/fisiología , Prosencéfalo/fisiología , Reproducción/fisiología , Caracteres Sexuales , Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/fisiología , Análisis de Varianza , Animales , Castración , Recuento de Células , Estradiol/análogos & derivados , Estradiol/farmacología , Estrógenos/farmacología , Femenino , Hipotálamo/anatomía & histología , Hipotálamo/efectos de los fármacos , Hipotálamo/fisiología , Hibridación in Situ , Lagartos/anatomía & histología , Masculino , Tamaño de los Órganos , Área Preóptica/anatomía & histología , Área Preóptica/efectos de los fármacos , Área Preóptica/fisiología , Prosencéfalo/anatomía & histología , Prosencéfalo/efectos de los fármacos , ARN Mensajero/metabolismo , Radioinmunoensayo
10.
J Neuroendocrinol ; 16(4): 340-7, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15089972

RESUMEN

The lamina terminalis, located in the anterior wall of the third ventricle, is comprised of the subfornical organ, median preoptic nucleus (MnPO) and organum vasculosum of the lamina terminalis (OVLT). The subfornical organ and OVLT are two of the brain's circumventricular organs that lack the blood-brain barrier, and are therefore exposed to the ionic and hormonal environment of the systemic circulation. Previous investigations in sheep and rats show that this region of the brain has a crucial role in osmoregulatory vasopressin secretion and thirst. The effects of lesions of the lamina terminalis, studies of immediate-early gene expression and electrophysiological data show that all three regions of the lamina terminalis are involved in osmoregulation. There is considerable evidence that physiological osmoreceptors subserving vasopressin release are located in the dorsal cap region of the OVLT and possibly also around the periphery of the subfornical organ and in the MnPO. The circulating peptide hormones angiotensin II and relaxin also have access to peptide specific receptors (AT(1) and LGR7 receptors, respectively) in the subfornical organ and OVLT, and both angiotensin II and relaxin act on the subfornical organ to stimulate water drinking in the rat. Studies that combined neuroanatomical tracing and detection of c-fos expression in response to angiotensin II or relaxin suggest that both of these circulating peptides act on neurones within the dorsal cap of the OVLT and the periphery of the subfornical organ to stimulate vasopressin release.


Asunto(s)
Hipotálamo/metabolismo , Hipotálamo/fisiología , Vasopresinas/metabolismo , Equilibrio Hidroelectrolítico/fisiología , Animales , Órgano Subfornical/metabolismo , Órgano Subfornical/fisiología
11.
Clin Endocrinol (Oxf) ; 57(3): 391-9, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12201833

RESUMEN

OBJECTIVE: Zinc may be a limiting factor in restricting catch-up growth in severely malnourished children. This study had two aims: (i) to examine the effect of different zinc supplementation regimens on IGF-I, its binding proteins and on markers of bone and collagen turnover in severely malnourished children and (ii) to investigate mechanisms underlying catch-up growth by examining changes in these markers during nutritional rehabilitation, their inter-relationships and their relationships with ponderal and linear growth. DESIGN: Double-blind randomized intervention study of three regimens of oral zinc supplementation. PATIENTS: One hundred and forty-one children, aged 6-36 months, mean (SD) age 15.4 (8.7) months, with day 1 weight-for-height SD score (whz) -2.6 (0.93) and height-for-age SD score (haz) -3.79 (1.29). MEASUREMENTS: Weight, height, lower leg length (by knemometry) at 15-day intervals from day 1 to day 90 of nutritional rehabilitation. Blood collection on days 1, 15 and 30 for IGF-I, IGFBP3, IGFBP2, bone alkaline phosphatase (BAP, osteoblast marker), procollagen type I C-terminal propeptide (PICP, marker of type I collagen synthesis), procollagen type III N-terminal propeptide (P3NP, marker of soft tissue type III collagen synthesis) and type I collagen telopeptide (ICTP, marker of type I collagen breakdown). RESULTS: There was early rapid weight gain during refeeding, whereas height gain occurred later in the trial. IGF-I, IGFBP3, BAP, PICP and P3NP were low or very low on day 1 compared to well-nourished age-matched European children, and all increased within 15 days (P < 0.001), with PICP and P3NP reaching levels higher than European norms. IGFBP2 and ICTP were high on day 1 and decreased over the same period (P < 0.001). There were no differences in anthropometric outcome or marker responses among zinc regimens. Day 1 whz was correlated with BAP, PICP and P3NP (P < 0.001). Changes in IGF-I, IGFBP3, BAP, PICP and P3NP over 30 days correlated with ponderal growth (whz change) over the same period (all P < 0.01). However, changes in these markers over 30 days correlated better with lower leg growth (all P < 0.01) and linear growth (haz change, P < 0.01 for PICP and P3NP, P < 0.05 for IGFBP3) measured over 90 compared with 30 days. At most time points, there were strong positive correlations (i) among IGF-I, IGFBP3, BAP, PICP and P3NP (P < 0.01) and (ii) between IGFBP2 and ICTP (P < 0.01). Conversely, IGFBP2 was negatively correlated with IGF-I, IGFBP3, BAP, PICP and P3NP at most time points (P < 0.01). CONCLUSIONS: We found no difference among zinc regimens in growth, IGF-I and its binding proteins or markers of bone and collagen turnover. Severe malnutrition was associated with low rates of bone and collagen synthesis and high rates of collagen degradation, and nutritional rehabilitation was associated with full or partial 'normalization' of the markers studied. Early weight gain and subsequent linear growth were associated with early increments in IGF-I, IGFBP3 and markers of bone and collagen formation. The study of these markers has provided additional insights into the mechanisms of the effects of malnutrition and refeeding on growth.


Asunto(s)
Suplementos Dietéticos , Trastornos del Crecimiento/tratamiento farmacológico , Trastornos Nutricionales/tratamiento farmacológico , Osteogénesis/efectos de los fármacos , Zinc/uso terapéutico , Antropometría , Estatura/efectos de los fármacos , Preescolar , Colágeno/metabolismo , Método Doble Ciego , Estudios de Seguimiento , Crecimiento/efectos de los fármacos , Trastornos del Crecimiento/etiología , Trastornos del Crecimiento/fisiopatología , Humanos , Lactante , Factor I del Crecimiento Similar a la Insulina/metabolismo , Trastornos Nutricionales/complicaciones , Trastornos Nutricionales/fisiopatología
12.
J Pept Sci ; 7(9): 495-501, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11587188

RESUMEN

The recently identified protein, insulin 3 (INSL3), has structural features that make it a bona fide member of the insulin superfamily. Its predicted amino acid sequence contains the classic two-peptide chain (A- and B-) structure with conserved cysteine residues that results in a disulphide bond disposition identical to that of insulin. Recently, the generation of insl3 knockout mice has demonstrated that testicular descent is blocked due to the failure of a specific ligament, the gubernaculum, to develop. The mechanism by which INSL3 exerts its action on the gubernaculum is currently unknown. The purpose of this study was to, for the first time, synthesize rat INSL3 and test its action on organ cultures of foetal rat gubernaculum. INSL3 also contains a cassette of residues Arg-X-X-X-Arg within the B-chain, a motif that is essential for characteristic activity of another related member of the superfamily, relaxin. Hence, the relaxin activity of rat INSL3 was also tested in two different relaxin bioassays. The primary structure of rat INSL3 was determined by deduction from its cDNA sequence and successfully prepared by solid phase peptide synthesis of the two constituent chains followed by their combination in solution. Following confirmation of its chemical integrity by a variety of analytical techniques, circular dichroism spectroscopy confirmed the presence of high beta-turn and alpha-helical content, with a remarkable spectral similarity to the synthetic ovine INSL3 peptide and to synthetic rat relaxin. The synthetic rat INSL3 bound with very low affinity to rat relaxin receptors and had no activity in a relaxin bioassay. Furthermore, it did not augment or antagonize relaxin activity. The rat INSL3 did however induce growth of foetal rat gubernaculum in whole organ cultures demonstrating that INSL3 has a direct action on this structure.


Asunto(s)
Proteínas/síntesis química , Proteínas/metabolismo , Secuencia de Aminoácidos , Animales , Bioensayo , Dicroismo Circular , Secuencia Conservada , AMP Cíclico/metabolismo , Cisteína/química , ADN Complementario/metabolismo , Relación Dosis-Respuesta a Droga , Insulina , Ligandos , Masculino , Datos de Secuencia Molecular , Péptidos/química , Unión Proteica , Estructura Terciaria de Proteína , Ratas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Testículo/embriología , Factores de Tiempo
14.
Pediatr Res ; 46(5): 581-7, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10541322

RESUMEN

In a longitudinal study of 25 preterm infants, we have examined the relationship of bone-specific alkaline phosphatase (ALP), C-terminal propeptide of type I collagen (PICP), N-terminal propeptide of type III procollagen (P3NP), C-terminal telopeptide of type I collagen, urinary pyridinoline (Pyd) and deoxypyridinoline (Dpd), with rates of gain in weight, length, and lower leg length and with bone mineral content (BMC), all measured at weekly intervals over the first 10 wk of life. Concentrations of all collagen markers were 10-fold higher than in older children. Each marker showed a distinctive pattern of postnatal change, with early increases in PICP and P3NP and decreases in ICTP reflecting postnatal growth. Once markers had reached a plateau during weeks 4-10, P3NP was positively correlated, whereas Pyd and Dpd were negatively correlated with rate of weight gain (r = +0.44, -0.46, and -0.40, respectively, p < 0.05). P3NP was also positively correlated with overall linear growth (r = +0.44, p < 0.05). PICP was strongly correlated with mean BMC (r = +0.63,p < 0.01) and with total BMC attained by the end of the study period (r = +0.81, p < 0.001). Bone ALP was positively correlated with the rate of bone mineral accretion (r = +0.55, p = 0.01). We conclude that the marker of soft-tissue collagen formation, P3NP, is a good marker for overall ponderal and linear growth in preterm infants, whereas the markers of collagen breakdown, Pyd and Dpd, have inverse relationships with weight gain. The osteoblast markers, PICP and bone ALP, seem to be good surrogate markers for bone mineralization in preterm infants. Markers may provide information on whole-body turnover of bone and collagen that is complementary to traditional physical measures of growth and bone mineralization.


Asunto(s)
Densidad Ósea/fisiología , Huesos/metabolismo , Colágeno/metabolismo , Recien Nacido Prematuro/metabolismo , Fosfatasa Alcalina/metabolismo , Biomarcadores , Peso al Nacer/fisiología , Enfermedad Crónica , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro/crecimiento & desarrollo , Enfermedades Pulmonares/metabolismo , Masculino , Caracteres Sexuales
15.
Endocrinology ; 140(1): 112-7, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9886814

RESUMEN

Doses of testosterone that fully activate male reproductive behavior in castrated adult male hamsters fail to elicit mounting and intromissions in prepubertal castrates, even when circulating levels of testosterone are equivalent in the two age groups. We hypothesize that this differential responsiveness to testosterone is mediated at least in part by the efficacy with which testosterone in the hypothalamus is aromatized to estradiol, an important hormone mediating male sexual behavior. Therefore, hypothalamic aromatase activity, as measured by the conversion of [3H]testosterone to [3H]estradiol in tissue homogenates, was assessed in four separate experiments: 1) intact prepubertal and adult male golden hamsters, 2 and 3) castrated adult or prepubertal males that received either a 0- or 2.5-mg dose of testosterone, and 4) castrated adult and prepubertal males treated with the 2.5-mg dose oftestosterone. These studies demonstrate that hypothalamic aromatase activity is significantly higher in adult males compared with prepubertal males, and that hypothalamic aromatase activity is increased by testosterone to the same extent in both the adult and prepubertal male hamster. Therefore, the failure of testosterone-treated castrated prepubertal male hamsters to engage in the full suite of male reproductive behaviors is not due to the inability of testosterone to be converted into estradiol in the hypothalamus. Differences in the ability of testosterone to increase aromatase activity in other brain regions, or differences in the action of testosterone and/or estradiol on other cellular processes must account for the inability of testosterone to facilitate male reproductive behavior in juvenile males.


Asunto(s)
Aromatasa/metabolismo , Hipotálamo/enzimología , Maduración Sexual/fisiología , Testosterona/fisiología , Envejecimiento/metabolismo , Animales , Castración , Cerebelo/enzimología , Cricetinae , Estradiol/sangre , Hipotálamo/efectos de los fármacos , Técnicas In Vitro , Cinética , Masculino , Mesocricetus , Testosterona/farmacología
17.
Artículo en Inglés | MEDLINE | ID: mdl-10177369

RESUMEN

The health care profession in the USA has traditionally attracted some of the best talent the country has to offer, with medical practitioners enjoying high incomes due to employer-paid medical indemnity insurance plans. There was no oversight process or quality standards governing the health care delivery process and no motivating factors to contain costs. Prior to the introduction of the Knox-Keene Act in the 1970s requiring employers to offer managed care as an alternative indemnity coverage, the only known managed care company was the Kaiser Permanente Medical Plan. Until just over a decade ago, the concept of managed care was stereotyped as a low quality method of health care delivery. Criticisms from providers themselves suggested managed care systems meant withholding medical care for the sake of profit; "production line" medicine, and compromise in the delivery of quality health care. In order to refute that notion and grow as an industry, managed health care companies were required to take steps to prove their integrity, high quality of care, and cost-effective methods. Today the industry is fast growing, setting management practices that are becoming benchmark standards for other industries too.


Asunto(s)
Benchmarking , Sistemas Prepagos de Salud/normas , Garantía de la Calidad de Atención de Salud , Prestación Integrada de Atención de Salud/normas , Competencia Económica , Humanos , Innovación Organizacional , Estados Unidos
19.
J Am Soc Nephrol ; 7(12): 2533-42, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8989731

RESUMEN

Two bumetanide-sensitive ion cotransporters that carry Na+, K+, and Cl- in a coupled fashion have been identified. One type, the "absorptive" isoform, carries these ions across the apical plasma membrane of the thick ascending limb of Henle's loop. Another isoform, the "secretory" cotransporter, has been identified in a number of epithelial tissues by physiological means, but its sites of expression in the kidney have not been fully characterized. Complementary DNA believed to code for the secretory isoform (called "BSC2" or "NKCC1") have recently been cloned. This study used a specific affinity-purified antipeptide antibody to this protein for immunolocalization in the rat kidney. Immunoblot studies using this antibody show abundant immunoreactivity against bands of 140-190 and 120 kd in the parotid gland, colon, and stomach, sites where the secretory form of the cotransporter has been identified by physiological techniques. This distribution supports the hypothesis that this isoform represents the secretory form of the cotransporter. Studies in the kidney revealed that the same bands are associated with membrane fractions chiefly in the outer medulla. Immunolocalizations show that immunoreactivity is selectively and intensely localized to the basolateral plasma membrane of a subfraction of outer medullary collecting duct cells. An independently produced monoclonal antibody (T4) specific for Na-K-Cl cotransporter displays the same localization. Dual localizations of cotransporter antibody with respect to antibody specific for principal cells (aquaporin-2) and intercalated cells (band 3 and H(+)-ATPase) show that cotransporter immunoreactivity is localized to alpha-intercalated cells of the outer medullary collecting duct in the rat. This distinctive localization suggests that the secretory form of the cotransporter may play a role in renal NH4+ and/or acid secretion by this cell type.


Asunto(s)
Proteínas Portadoras/metabolismo , Riñón/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Especificidad de Anticuerpos , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Membrana Celular/metabolismo , Cloruros/metabolismo , Immunoblotting , Inmunohistoquímica , Transporte Iónico , Riñón/citología , Corteza Renal/citología , Corteza Renal/metabolismo , Médula Renal/citología , Médula Renal/metabolismo , Túbulos Renales Colectores/citología , Túbulos Renales Colectores/metabolismo , Datos de Secuencia Molecular , Potasio/metabolismo , Ratas , Sodio/metabolismo , Simportadores de Cloruro de Sodio-Potasio
20.
Cancer ; 76(10): 1709-14, 1995 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8625038

RESUMEN

BACKGROUND: Metastatic colorectal cancer is generally incurable. The most active regimen available, 5-fluorouracil (5-FU) and folinic acid (Leucovorin), produces response rates of approximately 25% to 30%. Methyl-lomustine is a nitrosourea with modest activity against colorectal cancer. A randomized trial was undertaken to evaluate the impact the addition of methyl-lomustine would have on response, duration of survival, and survival rates in patients with advanced colorectal cancer. METHODS: The methyl-lomustine/5-FU/Leucovorin (MFL) regimen consisted of methyl-lomustine (110 mg/m2), administered on Day 1 of each 8-week cycle with six weekly boluses of 5-FU (600 mg/m2), and Leucovorin (500 mg/m2). The FL treatment arm consisted of the administration of 5-FU and Leucovorin as described above. Patients were evaluated for response and toxicity after each 8-week cycle. RESULTS: Of 319 patients included in this trial, 297 (93.1%) had disease evaluable for response and toxicity: 145 received MFL, and 152 received FL. In this trial, 526 courses of MFL and 529 courses of FL were administered. Methyl-lomustine/5-FU/Leucovorin treatment resulted in 4 complete and 30 partial responses (response rate, 21.9%), and FL treatment resulted in 9 complete and 33 partial responses (response rate, 26.4%). There was no significant difference in median survival duration between patients in the two arms (MFL = 48 weeks, FL = 51 weeks). However, MFL was significantly more toxic with greater myelosuppression than was FL (Grade 3-4 neutropenia: MFL = 56 patients, FL = 27 patients, P < 0.001; Grade 3-4 thrombocytopenia: MFL = 49 patients, FL = 2 patients, P < 0.001; Grade 3-4 anemia: MFL = 15 patients, FL = 6 patients, P < 0.001; and more prolonged median duration of granulocytopenia: MFL = 9 days, FL = 7 days, P < 0.001; and thrombocytopenia: MFL = 14 days, FL = 7.5 days, P < 0.001). CONCLUSION: Because the addition of methyl-lomustine in the MFL schedule markedly increased the toxicity of the regimen and because the FL regimen was as effective as MFL, the authors recommend that Leucovorin and 5-FU remain the treatment choice for treating patients with metastatic colorectal cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Colorrectales/mortalidad , Femenino , Fluorouracilo/administración & dosificación , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Semustina/administración & dosificación
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