RESUMO
Many patient-reported outcome measures (PROMs) have been used to study quality of life (QOL) in the skin cancer population. Advanced melanoma and non-melanoma skin cancer (NMSC) may be associated with increased morbidity, mortality, and treatment side effects; however, it is unclear which PROM is valid and appropriate to use in these populations for both clinical and research purposes. We aimed to identify the PROMs that have been used to measure QOL in advanced skin cancer patients and determine which of these PROMs have been validated to assess QOL outcomes in this population. A PubMed and EMBASE search was conducted from its inception to March 2021 according to PRISMA guidelines with a comprehensive list of search terms under three main topics: (1) PROM; (2) advanced skin cancer; and (3) staging and interventions. We included articles utilizing a PROM measuring QOL and having a patient population with advanced skin cancer defined as melanoma stage > T1a or non-melanoma AJCC stage T3 or greater. Advanced skin cancer patients were also defined as those with metastasis or requiring adjuvant therapy (systemic chemotherapy, radiation, and immunotherapy). Studies were excluded according to the following criteria: mix of low-risk and advanced skin cancer patients in the study population without stratification into low-risk and advanced groups, stage T1a melanoma or mix of stages without stratification, low-risk NMSC, no PROM (i.e., study specific questionnaires), non-English publication, review article or protocol paper, conference abstract, or populations including non-skin cancers. A total of 1,998 articles were identified. 82 met our inclusion criteria resulting in 22 PROMs: five generic health-related (QWB-SA, AQoL-8D, EQ-5D, SF-36, and PRISM), six general cancer (EORTC QLQ-C30, EORTC QLQ-C36, LASA, IOC, Rotterdam Symptom Checklist, and FACT-G), nine disease-focused or specialized (EORTC QLQ-H&N35, EORTC QLQ-MEL38, EORTC QLQ-BR23, Facial Disability Index, FACT-H&N, FACT-BRM, FACT-B, FACT-M, and scqolit), and two general dermatology (Skindex-16 and DLQI) PROMs. All PROMs have been generally validated except for EORTC QLQ-MEL38. Only two PROMs have been validated in the advanced melanoma population: FACT-M and EORTC QLQ-C36. No PROMS have been validated in the advanced NMSC population. The PROMs that were validated in the advanced melanoma population do not include QOL issues unique to advanced skin tumors such as odor, bleeding, itching, wound care burden, and public embarrassment. Breast cancer and head and neck cancer instruments were adapted but not validated for use in the advanced skin cancer population due to the lack of an adequate instrument for this population. This study highlights the need for PROM instrument validation or creation specifically geared toward the advanced skin cancer population. Future studies should aim to develop and validate a PROM to assess QOL in this population.
Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Qualidade de Vida , Neoplasias Cutâneas/terapia , Melanoma/terapia , Inquéritos e Questionários , Medidas de Resultados Relatados pelo PacienteRESUMO
Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder (PCSM-TCLPD) was reclassified in 2016 as a rare benign entity with an excellent prognosis, yet its clinical features and best treatments remain poorly defined. We collected clinical data, treatments, and treatment-responses from our institution's patients with PCSM-TCLPD through September 2018 and an identical PubMed review through June 2021. Among 36 cases (median-age 54 years; 58.3% head/neck), diagnostic biopsy resulted in sustained complete remission (CR) in 13/33 punch/shave biopsies and 3/3 excisional biopsies. The remaining 20 patients further required topical corticosteroids (n = 5); intralesional corticosteroids (n = 1); surgical-excision (n = 5); electron-beam-radiation (n = 6); or brachytherapy (n = 3). All patients ultimately achieved CR, excluding one patient continuing treatment at end-of-study. 57/59 (96.6%) of institutional and literature-reported radiation-treated patients experienced CR. No institutional cases progressed beyond skin; 5/209 (2.4%) literature-reported cases progressed to systemic/extracutaneous involvement, all pre-reclassification. PCSM-TCLPD responds well to local-directed therapy including radiation, and only rarely if ever progresses.
Assuntos
Linfoma Cutâneo de Células T , Transtornos Linfoproliferativos , Dermatopatias , Neoplasias Cutâneas , Humanos , Pessoa de Meia-Idade , Linfoma Cutâneo de Células T/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/patologia , Estudos Retrospectivos , Linfócitos T CD4-Positivos/patologia , Dermatopatias/patologia , Transtornos Linfoproliferativos/terapia , Resultado do TratamentoRESUMO
Plasmodium species produce an ortholog of the cytokine macrophage migration inhibitory factor, PMIF, which modulates the host inflammatory response to malaria. Using a novel RNA replicon-based vaccine, we show the impact of PMIF immunoneutralization on the host response and observed improved control of liver and blood-stage Plasmodium infection, and complete protection from re-infection. Vaccination against PMIF delayed blood-stage patency after sporozoite infection, reduced the expression of the Th1-associated inflammatory markers TNF-α, IL-12, and IFN-γ during blood-stage infection, augmented Tfh cell and germinal center responses, increased anti-Plasmodium antibody titers, and enhanced the differentiation of antigen-experienced memory CD4 T cells and liver-resident CD8 T cells. Protection from re-infection was recapitulated by the adoptive transfer of CD8 or CD4 T cells from PMIF RNA immunized hosts. Parasite MIF inhibition may be a useful approach to promote immunity to Plasmodium and potentially other parasite genera that produce MIF orthologous proteins.
Assuntos
Imunidade Adaptativa/efeitos dos fármacos , Anticorpos Antiprotozoários/biossíntese , Fatores Inibidores da Migração de Macrófagos/antagonistas & inibidores , Vacinas Antimaláricas/administração & dosagem , Malária/prevenção & controle , Proteínas de Protozoários/antagonistas & inibidores , Vacinas de DNA/administração & dosagem , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/parasitologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/parasitologia , Feminino , Expressão Gênica , Centro Germinativo/efeitos dos fármacos , Centro Germinativo/imunologia , Centro Germinativo/parasitologia , Memória Imunológica/efeitos dos fármacos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Fatores Inibidores da Migração de Macrófagos/genética , Fatores Inibidores da Migração de Macrófagos/imunologia , Malária/imunologia , Malária/parasitologia , Vacinas Antimaláricas/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Plasmodium berghei/efeitos dos fármacos , Plasmodium berghei/genética , Plasmodium berghei/imunologia , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , RNA de Protozoário/genética , RNA de Protozoário/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Vacinas de DNA/biossínteseRESUMO
Leishmania major encodes 2 orthologs of the cytokine macrophage migration inhibitory factor (MIF), whose functions in parasite growth or in the host-parasite interaction are unknown. To determine the importance of Leishmania-encoded MIF, both LmMIF genes were removed to produce an mif(-/-) strain of L. major This mutant strain replicated normally in vitro but had a 2-fold increased susceptibility to clearance by macrophages. Mice infected with mif(-/-) L. major, when compared to the wild-type strain, also showed a 3-fold reduction in parasite burden. Microarray and functional analyses revealed a reduced ability of mif(-/-) L. major to activate antigen-presenting cells, resulting in a 2-fold reduction in T-cell priming. In addition, there was a reduction in inflammation and effector CD4 T-cell formation in mif(-/-) L. major-infected mice when compared to mice infected with wild-type L. major Notably, effector CD4 T cells that developed during infection with mif(-/-) L. major demonstrated statistically significant differences in markers of functional exhaustion, including increased expression of IFN-γ and IL-7R, reduced expression of programmed death-1, and decreased apoptosis. These data support a role for LmMIF in promoting parasite persistence by manipulating the host response to increase the exhaustion and depletion of protective CD4 T cells.-Holowka, T., Castilho, T. M., Baeza Garcia, A., Sun, T., McMahon-Pratt, D., Bucala, R. Leishmania-encoded orthologs of macrophage migration inhibitory factor regulate host immunity to promote parasite persistence.
Assuntos
Regulação da Expressão Gênica/fisiologia , Leishmania major/metabolismo , Leishmaniose Cutânea/parasitologia , Fatores Inibidores da Migração de Macrófagos/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Diferenciação de Linfócitos B/metabolismo , Apoptose/fisiologia , Linfócitos T CD4-Positivos/fisiologia , Clonagem Molecular , Deleção de Genes , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Leishmaniose Cutânea/imunologia , Fatores Inibidores da Migração de Macrófagos/genética , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos SCID , Organismos Geneticamente Modificados , Análise Serial de Proteínas , Proteínas de Protozoários/genéticaRESUMO
BACKGROUND/PURPOSE: Bone resorption and soft-tissue defects are the typical physiologic responses after tooth extraction. Various dental ridge augmentation techniques have been applied and lack of the soft tissue is the major factor causing the failure. We propose that the adipose-derived stem cell can be useful in soft-tissue augmentation in dental applications. The objective of this study was to optimize the operation procedures for the isolation of adipose stem cells and tissues. Accelerated clinical protocols for effective transplantation of adipose tissue with high amount of adipose stem cells shall be developed. MATERIALS AND METHODS: Operation parameters were designed and optimized for the extraction of adipose tissue-derived stromal vascular cells. The optimized accelerated procedure was washing the lipoaspirate samples one time. Collagenase was then added and samples were incubated in a water bath for 30 minutes at 37°C and centrifuged at 1200g for 3 minutes. A mouse animal model was applied to evaluate the soft-tissue-filling effects using the optimized procedure. RESULTS: The animal model tests demonstrated the filling and regeneration of the soft tissues with significant angiogenesis. CONCLUSION: This pilot study demonstrated the feasibility of soft-tissue augmentation applications.
RESUMO
The inability to acquire protective immunity against Plasmodia is the chief obstacle to malaria control, and inadequate T-cell responses may facilitate persistent blood-stage infection. Malaria is characterized by a highly inflammatory cytokine milieu, and the lack of effective protection against infection suggests that memory T cells are not adequately formed or maintained. Using a genetically targeted strain of Plasmodium berghei, we observed that the Plasmodium ortholog of macrophage migration inhibitory factor enhanced inflammatory cytokine production and also induced antigen-experienced CD4 T cells to develop into short-lived effector cells rather than memory precursor cells. The short-lived effector CD4 T cells were more susceptible to Bcl-2-associated apoptosis, resulting in decreased CD4 T-cell recall responses against challenge infections. These findings indicate that Plasmodia actively interfere with the development of immunological memory and may account for the evolutionary conservation of parasite macrophage migration inhibitory factor orthologs.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Citocinas/imunologia , Malária Falciparum/imunologia , Plasmodium berghei/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Animais , Apoptose/imunologia , Citocinas/genética , Evolução Molecular , Humanos , Memória Imunológica/genética , Malária Falciparum/genética , Camundongos , Camundongos Endogâmicos BALB C , Plasmodium berghei/genética , Plasmodium falciparum/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Proteínas de Protozoários/genéticaRESUMO
Cells respond to defects in mitochondrial function by activating signaling pathways that restore homeostasis. The mitochondrial peptide exporter HAF-1 and the bZip transcription factor ATFS-1 represent one stress response pathway that regulates the transcription of mitochondrial chaperone genes during mitochondrial dysfunction. Here, we report that GCN-2, an eIF2α kinase that modulates cytosolic protein synthesis, functions in a complementary pathway to that of HAF-1 and ATFS-1. During mitochondrial dysfunction, GCN-2-dependent eIF2α phosphorylation is required for development as well as the lifespan extension observed in Caenorhabditis elegans. Reactive oxygen species (ROS) generated from dysfunctional mitochondria are required for GCN-2-dependent eIF2α phosphorylation but not ATFS-1 activation. Simultaneous deletion of ATFS-1 and GCN-2 compounds the developmental defects associated with mitochondrial stress, while stressed animals lacking GCN-2 display a greater dependence on ATFS-1 and stronger induction of mitochondrial chaperone genes. These findings are consistent with translational control and stress-dependent chaperone induction acting in complementary arms of the UPR(mt).
Assuntos
Transportadores de Cassetes de Ligação de ATP , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Mitocôndrias , Biossíntese de Proteínas , Fatores de Transcrição , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Chaperonas Moleculares , Fosforilação , Biossíntese de Proteínas/genética , Dobramento de Proteína , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismoRESUMO
The role of proinflammatory cytokine production in the pathogenesis of malaria is well established, but the identification of the parasite products that initiate inflammation is not complete. Hemozoin is a crystalline metabolite of hemoglobin digestion that is released during malaria infection. In the present study, we characterized the immunostimulatory activity of pure synthetic hemozoin (sHz) in vitro and in vivo. Stimulation of naive murine macrophages with sHz results in the MyD88-independent activation of NF-kappaB and ERK, as well as the release of the chemokine MCP-1; these responses are augmented by IFN-gamma. In macrophages prestimulated with IFN-gamma, sHz also results in a MyD88-dependent release of TNF-alpha. Endothelial cells, which encounter hemozoin after schizont rupture, respond to sHz by releasing IL-6 and the chemokines MCP-1 and IL-8. In vivo, the introduction of sHz into the peritoneal cavity produces an inflammatory response characterized by neutrophil recruitment and the production of MCP-1, KC, IL-6, IL-1alpha, and IL-1beta. MCP-1 and KC are produced independently of MyD88, TLR2/4 and TLR9, and components of the inflammasome; however, neutrophil recruitment, the localized production of IL-1beta, and the increase in circulating IL-6 require MyD88 signaling, the IL-1R pathway, and the inflammasome components ICE (IL-1beta-converting enzyme), ASC (apoptosis-associated, speck-like protein containing CARD), and NALP3. Of note, inflammasome activation by sHz is reduced by allopurinol, which is an inhibitor of uric acid synthesis. These data suggest that uric acid is released during malaria infection and may serve to augment the initial host response to hemozoin via activation of the NALP3 inflammasome.
Assuntos
Proteínas de Transporte/metabolismo , Hemeproteínas/imunologia , Inflamação/parasitologia , Malária Falciparum/imunologia , Plasmodium falciparum , Ácido Úrico/metabolismo , Alopurinol/farmacologia , Animais , Proteínas Reguladoras de Apoptose , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Transporte/imunologia , Quimiocina CCL2/imunologia , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/imunologia , Quimiocina CXCL1/metabolismo , Proteínas do Citoesqueleto/imunologia , Proteínas do Citoesqueleto/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Endoteliais/parasitologia , MAP Quinases Reguladas por Sinal Extracelular/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hemeproteínas/farmacologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Interferon gama/farmacologia , Interleucina-1alfa/imunologia , Interleucina-1alfa/metabolismo , Interleucina-1beta/imunologia , Interleucina-1beta/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Interleucina-8/imunologia , Interleucina-8/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/parasitologia , Malária Falciparum/parasitologia , Camundongos , Fator 88 de Diferenciação Mieloide/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/imunologia , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Receptores Toll-Like/imunologia , Receptores Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Ácido Úrico/antagonistas & inibidoresRESUMO
BACKGROUND: Postoperative nausea and vomiting (PONV) remain common complications after elective surgery. Prophylactic antiemetic drugs are frequently administered to patients with well known risk factors for developing PONV. We designed this prospective observational study to assess the relationship between common patient risk factors for developing PONV and the occurrence of early (0-24 h) versus late (24-72 h) emetic symptoms. METHODS: One hundred thirty patients undergoing elective laparoscopic (n = 88) or plastic (n = 42) surgery were assigned a risk score for developing PONV based on the Apfel risk scoring system, which assigns one point each for female gender, nonsmoking status, history of PONV or motion sickness, and postoperative opioid use. It was assumed that all patients would receive an opioid analgesic in the postoperative period. The patients received 0, 1, 2, or 3 antiemetic drugs for prophylaxis. The occurrence of nausea, vomiting, and need for rescue antiemetics was assessed at specific time intervals from 0 to 6, 6-24, and 24-72 h after surgery. In addition, the impact of PONV on recovery of normal activities of daily living was assessed using a standardized patient questionnaire. RESULTS: One or more prophylactic antiemetics were administered to 87%, 90%, and 95% of the patients in the two, three, and four Apfel risk-factor groups, respectively. In the presence of three or four risk factors, >/=2 antiemetics were administered to 56% and 75% of the patients, respectively. Vomiting was reported in 11% and 22% of patients in the three and four risk factor groups compared with 6% in the two risk factor group at 0-6 h, and 13% and 27% (vs 0%) at 6-24 h, respectively. However, in the 24-72 h postoperative period, the incidences of emesis were low and did not differ in the three risk groups (9%, 5%, and 11%, respectively). The occurrence of moderate-to-severe nausea was increased in the higher risk groups at 0-6 h and 6-24 h (19%-28% vs 6% and 20%-30% vs 9%, respectively). However, the incidences of nausea in the 24-72 h period in the three and four risk factor groups were not different from the two-risk factor group (5% and 8% vs 6%, respectively). The need for rescue antiemetics and interference of emetic symptoms with normal activities was greater in the four risk factor group compared with the two and three risk factor groups. CONCLUSION: Despite the frequent use of multiple antiemetic drugs for prophylaxis, an Apfel risk score of three or four (vs 2) was associated with a higher incidence of emetic sequelae in the first 24 h after surgery. However, the occurrence of late (24-72 h) emetic symptoms was low and appeared to be unrelated to the patient's Apfel risk score.
Assuntos
Náusea e Vômito Pós-Operatórios/etiologia , Adolescente , Adulto , Idoso , Antieméticos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Náusea e Vômito Pós-Operatórios/prevenção & controle , Fatores de RiscoRESUMO
BACKGROUND: Controversy continues to surround the use of cyclooxygenase (COX)-2 inhibitors in the perioperative period. We designed this randomized, double-blind, placebo-controlled study to examine the hypothesis that administration of celecoxib preoperatively or postoperatively and for 3 days after major plastic surgery would improve pain control and clinically important patient outcomes. Another objective of the study was to determine whether perioperative administration of celecoxib offered any advantages over postoperative administration alone. METHODS: One hundred and twenty healthy consenting patients undergoing major plastic surgery (e.g., breast augmentation, abdominoplasty procedures) using a standardized general anesthetic technique were randomized to one of three treatment groups: 1) control group (n = 40) received two placebos orally before and after surgery, as well as one placebo BID for 3 days after surgery; 2) postoperative group (n = 40) received two placebos before surgery and 2 celecoxib 200 mg p.o. after surgery, followed by one celecoxib 200 mg p.o. BID on postoperative day #1, #2 and #3; and 3) perioperative group (n = 40) received 2 celecoxib 200 mg p.o. 30-90 min before surgery, and two placebos after surgery, followed by one celecoxib 200 mg p.o. BID on postoperative day #1, #2, and #3. Pain scores, the need for rescue analgesics, and side effects were recorded at specific time intervals in the postoperative period. Follow-up evaluations were performed at 24, 48, 72 h, and 7 days after surgery to assess postdischarge pain, analgesic requirements, return of bowel function, resumption of normal daily activities, quality of recovery, as well as patient satisfaction with pain management. RESULTS: Compared with the control group, the two celecoxib groups had similar significant reductions in postoperative pain and need for opioid analgesics during the first three postoperative days (P < 0.01). Patients recovered bowel function 1 day earlier and resumed normal activities 2 days earlier in the celecoxib groups. In addition, patient satisfaction with pain management and quality of recovery were significantly improved in the celecoxib (versus control) groups (P < 0.05). CONCLUSION: Celecoxib (400 mg p.o.) administered on the day of surgery and for 3 days postoperatively is effective in improving postoperative pain management, as well as the speed and quality of recovery after major plastic surgery. However, perioperative administration offers no advantages over simply giving the drug after surgery.
Assuntos
Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Dor Pós-Operatória/prevenção & controle , Procedimentos de Cirurgia Plástica/efeitos adversos , Pirazóis/administração & dosagem , Sulfonamidas/administração & dosagem , Atividades Cotidianas , Adulto , Analgésicos Opioides/uso terapêutico , Celecoxib , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Defecação/efeitos dos fármacos , Método Duplo-Cego , Esquema de Medicação , Feminino , Motilidade Gastrointestinal/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Medição da Dor , Dor Pós-Operatória/etiologia , Satisfação do Paciente , Assistência Perioperatória , Cuidados Pós-Operatórios , Pirazóis/efeitos adversos , Sulfonamidas/efeitos adversos , Fatores de Tempo , Resultado do TratamentoRESUMO
An analysis of the protein profiles of intact worms and isolated tissues of adult male and female Toxocara canis worms was conducted. Soluble proteins recovered from homogenized whole specimens and dissected tissues (body wall, reproductive tract, esophagus and intestine) of T. canis adults from several different canine hosts were separated by size using gradient sodium dodecyl sulfate electrophoresis (SDS-PAGE) and visualized with silver staining. SDS-PAGE profiles of worms from different hosts were found to be virtually identical irrespective of sex or tissue type. Recovered proteins ranged in size from 3.4 to 325 kDa. As expected, variations existed between the protein profiles of different body tissues, with only slight variations between the sexes. The largest number of recovered proteins was present in the female reproductive tract extracts.
Assuntos
Proteínas de Helminto/metabolismo , Toxocara canis/metabolismo , Animais , Doenças do Cão/parasitologia , Cães , Feminino , Regulação da Expressão Gênica , Masculino , Toxocaríase/parasitologiaRESUMO
Normal aerobic metabolic rates persist in the early chicken embryo after elimination of cardiac output, but the dependence of tissue growth and differentiation on blood flow is unknown in these early stages. We partially ligated (25-50% occlusion) the ventricular outflow tract of Hamburger-Hamilton stage (HH) 16-18 embryos, producing a wide range of cardiac output. For the next approximately 48 h (to HH 24), we measured heart rate (HR), stroke volume (SV), and cardiac output (CO), as well as these growth indicators: eye diameter, chorioallantoic vessel density, and body mass. Acutely, HR declined with partial ligation (from 108 to 98 beats/min). Paradoxically, SV and CO decreased sharply in most embryos but increased in others, collectively producing the desired large variation (up to 25-fold) in CO and permitting assessment of tissue growth over a very large range of blood perfusion. Eye diameter doubled (from 0.6 to 1.2 mm) with development from HH 16 to HH 24, but within a developmental cohort there was no significant correlation between eye diameter and CO over a 25-fold range of CO. Similarly, chorioallantoic membrane vessel index was independent of CO over the CO range at all stages. Finally, body mass increase during development was not significantly affected by partial conal truncal ligation. Collectively, these data suggest that normal eye and vessel growth and body mass accumulation occur independent of their rate of blood perfusion, supporting the hypothesis of prosynchronotropy-that the heart begins to beat and generate blood flow in advance of the actual need for convective blood flow to tissues.