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1.
Math Biosci Eng ; 20(11): 19686-19709, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-38052620

RESUMO

Past works on partially diffusive models of diseases typically rely on a strong assumption regarding the initial data of their infection-related compartments in order to demonstrate uniform persistence in the case that the basic reproduction number $ \mathcal{R}_0 $ is above 1. Such a model for avian influenza was proposed, and its uniform persistence was proven for the case $ \mathcal{R}_0 > 1 $ when all of the infected bird population, recovered bird population and virus concentration in water do not initially vanish. Similarly, a work regarding a model of the Ebola virus disease required that the infected human population does not initially vanish to show an analogous result. We introduce a modification on the standard method of proving uniform persistence, extending both of these results by weakening their respective assumptions to requiring that only one (rather than all) infection-related compartment is initially non-vanishing. That is, we show that, given $ \mathcal{R}_0 > 1 $, if either the infected bird population or the viral concentration are initially nonzero anywhere in the case of avian influenza, or if any of the infected human population, viral concentration or population of deceased individuals who are under care are initially nonzero anywhere in the case of the Ebola virus disease, then their respective models predict uniform persistence. The difficulty which we overcome here is the lack of diffusion, and hence the inability to apply the minimum principle, in the equations of the avian influenza virus concentration in water and of the population of the individuals deceased due to the Ebola virus disease who are still in the process of caring.


Assuntos
Doenças Transmissíveis , Doença pelo Vírus Ebola , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Animais , Humanos , Influenza Aviária/epidemiologia , Doença pelo Vírus Ebola/veterinária , Aves , Água , Influenza Humana/epidemiologia
2.
Ecology ; 100(11): e02779, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31168782
5.
Math Med Biol ; 35(4): 427-445, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29088361

RESUMO

We study the systems of partial differential equations with diffusion that model the dynamics of infectious diseases without life-time immunity, in particular the cases of cholera from Wang & Wang (2015, J. Biol. Dyn., 9, 233-261) and avian influenza from Vaidya et al. (2012, Discrete Contin. Dyn. Syst. Ser. B, 17, 2829-2848). In both works, similarly to all others in the literature on various models of infectious diseases and more, it had to be assumed for a technical reason that the diffusivity coefficients of the susceptible, infected and recovered individuals, humans or birds, had to be identical in order to prove the existence of their unique solutions for all time. Considering that such uniform diffusivity strengths among the susceptible, infected and recovered hosts may not always be plausible in real world, we investigate the global well-posedness issue when such conditions are relaxed. In particular for the cholera model from Wang & Wang (2015, J. Biol. Dyn., 9, 233-261), we prove the global well-posedness with no condition on the diffusivity coefficients at all. For the avian influenza model from Vaidya et al. (2012, Discrete Contin. Dyn. Syst. Ser. B, 17, 2829-2848), we prove the global well-posedness with no condition on the diffusivity coefficients if the spatial dimension is one, and under a partial condition that the diffusivity coefficients of the susceptible and the infected hosts are same otherwise.


Assuntos
Cólera , Doenças Transmissíveis , Influenza Aviária , Modelos Teóricos , Animais , Aves , Humanos , Imunidade/imunologia
6.
Masui ; 66(3): 316-319, 2017 03.
Artigo em Japonês | MEDLINE | ID: mdl-30380227

RESUMO

A 97-year-old woman with severe back pain was transferred to our hospital. She was able to perform activities of daily living independently and had no neu- rological deficit or dementia before her admission. Con- trast-enhanced computed tomography revealed a rup- ture in the descending aorta and thrombosed type A aortic dissection. We carefully explained the need for and the risks associated with surgery to the patient and her family. After an informed consent had been obtained, she was taken to the operating room for an emergency surgery. Anesthetic management was uneventful. Trans- esophageal echocardiography was useful to evaluate her cardiac function and aortic dissection. We per- formed replacement of the total aortic arch and descending aorta successfully. On the 55th postopera- tive day, she was transferred to another hospital to undergo further physical therapy. The total hospital- ization cost was nearly 9.8 million yen. The medical cost was high in our case. In cases of nonagenarians who require an emergency cardiac surgery, we should consider the patients' age, preoperative activities of daily living, and postoperative quality of life when making decisions on surgery. The patient in our case needed to be carefully treated for airway and swallow- ing management in the early perioperative period.


Assuntos
Dissecção Aórtica/cirurgia , Atividades Cotidianas , Idoso de 80 Anos ou mais , Aorta Torácica/cirurgia , Ecocardiografia Transesofagiana , Feminino , Humanos , Período Perioperatório , Qualidade de Vida , Reimplante , Trombose , Tomografia Computadorizada por Raios X
8.
Math Biosci Eng ; 14(2): 559-579, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27879114

RESUMO

We study the global stability issue of the reaction-convection-diffusion cholera epidemic PDE model and show that the basic reproduction number serves as a threshold parameter that predicts whether cholera will persist or become globally extinct. Specifically, when the basic reproduction number is beneath one, we show that the disease-free-equilibrium is globally attractive. On the other hand, when the basic reproduction number exceeds one, if the infectious hosts or the concentration of bacteria in the contaminated water are not initially identically zero, we prove the uniform persistence result and that there exists at least one positive steady state.


Assuntos
Cólera/epidemiologia , Epidemias/estatística & dados numéricos , Modelos Biológicos , Número Básico de Reprodução , Humanos , Microbiologia da Água
9.
Endocr J ; 63(11): 1001-1006, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27523100

RESUMO

In cases of thyroid papillary carcinoma, a less aggressive cancer, surgeons may hesitate to perform total thyroidectomy on patients with poor general condition because these may experience longer survival without undergoing surgery. To investigate the influence of general patient condition on the patients' survival who received total thyroidectomy, we utilized the American Society of Anesthesiologists Physical Status (ASA-PS). We retrospectively reviewed all patients undergoing total thyroidectomy under general anesthesia and graded by ASA-PS between 2004 and 2014. Patients with anaplastic carcinoma and metastatic thyroid renal cell carcinoma were excluded. There were 77 (30%), 149 (58%), and 30 (12%) ASA-PS 1, 2, and 3 cases, respectively. Patient age increased significantly with increasing ASA-PS score (median age of 53, 64, and 71 years for ASA-PS 1, 2, and 3). Hospitalization periods extended significantly for patients with ASA-PS 3. Twenty patients died during the study (3.89 median years). Five-year overall survival rates were 100%, 93%, and 79% for ASA-PS 1, 2 and 3, respectively. Patients in the ASA-PS 1 group had significantly better prognosis by log-rank test. Univariate analysis showed an increased risk of death as ASA-PS score increased (hazard ratio: 3.03, 95% confidence interval: 1.55-5.92, p=0.00). In multivariate analysis, including patient age and presence of malignancy, patient age was the only significant predictor of overall survival (hazard ratio: 1.09 by year, 95% confidence interval: 1.03-1.14, p=0.00). We concluded that a high ASA-PS score should not inhibit performance of total thyroidectomy if a patient's age is suitable for the surgery.


Assuntos
Anestesia Geral/normas , Anestesiologistas/normas , Carcinoma , Indicadores Básicos de Saúde , Neoplasias da Glândula Tireoide , Tireoidectomia/efeitos adversos , Tireoidectomia/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral/mortalidade , Anestesiologistas/organização & administração , Carcinoma/epidemiologia , Carcinoma/mortalidade , Carcinoma/cirurgia , Carcinoma Papilar , Humanos , Pessoa de Meia-Idade , Morbidade , Prognóstico , Estudos Retrospectivos , Sociedades Médicas/normas , Taxa de Sobrevida , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/reabilitação , Estados Unidos/epidemiologia , Adulto Jovem
10.
J Theor Biol ; 404: 10-14, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27220745

RESUMO

Plant galls, induced by arthropods and various other organisms have an intimate relationship with host plants, and gall-inducers have limited mobility. In addition to their own photosynthesis, galls are resource sinks rich with nutrients, with neighboring plant organs commonly serving as external photosynthate sources. Galls, if not well defended, may therefore be attractive food sources for herbivores. Galls produced by some aphids, jumping plant lice, thrips, and gall midges in Japan, Palearctic region and in the Middle East visually resemble lepidopteran caterpillars. I propose that such visual resemblance may reduce herbivory of galls and surrounding plant tissues, resulting in an increase in galler survival due to reduced gall damage and in enhanced galler growth due to improved nutrient inflow to the galls, when herbivores avoid colonizing or consuming plant parts that look as if they have been occupied by other herbivores. Potential predators and parasitoids of caterpillars may be attracted to the caterpillar-like galls and then attack real caterpillars and other invertebrate herbivores, which would also be beneficial for both gallers and their hosts.


Assuntos
Mimetismo Biológico , Herbivoria/fisiologia , Tumores de Planta/parasitologia , Animais , Larva/fisiologia , Modelos Biológicos
11.
Masui ; 65(2): 168-71, 2016 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-27017774

RESUMO

Madelung's disease is a rare disorder characterized by multiple, symmetric fatty tissues. The patient, 72-year-old man was admitted to our hospital for abdominal surgery for liver cancer. He had extreme fatty accumulations involving head and neck. We expected difficult airway because of his fatty tissues, and we perfomed awake intubation by Airway Scope. We confirmed the airway by using tube exchanger at extubation. We should choose a proper airway management technique to reduce the incidences of airway complications.


Assuntos
Manuseio das Vias Aéreas/métodos , Lipomatose Simétrica Múltipla/complicações , Neoplasias Hepáticas/cirurgia , Assistência Perioperatória , Idoso , Extubação/métodos , Humanos , Intubação Intratraqueal/métodos , Masculino
13.
JA Clin Rep ; 2(1): 7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29497662

RESUMO

No successful resuscitation has ever been reported about intraoperative cardiopulmonary resuscitation (CPR) for an extended period of time in the lateral position. Here we report a case of successful resuscitation without any neurological complication after cardiac arrest due to massive hemorrhage and 25 min of CPR in the lateral position. The patient was a 65-year-old man. During open hemostasis for the postoperative hemorrhage, the patient's rhythm changed sinus to ventricular fibrillation (VF), followed by asystole. We started CPR immediately with the patient in the left lateral position. Chest compression was performed by two practitioners, one pressing patient's sternum and the other pressing simultaneously patient's mid-thoracic spine from his back. During CPR, though the value of end-tidal CO2 (EtCO2) was significantly low (around 5-20 mmHg), the value of systolic arterial pressure was kept about 35-50 mmHg, and diastolic pressure about 20-30 mmHg. After the 25 min of lateral CPR, he achieved the return of spontaneous circulation (ROSC). He was hemodynamically stable after ROSC. He regained his consciousness at the next postoperative day. He was discharged from our hospital on the 60th day of operation without any cardiac and neurological complication. Successful neurological outcome suggests that we may expect satisfactory neurological outcome even in the case of lateral position and prolonged CPR if we perform effective CPR with the feedback of arterial blood pressure and EtCO2 and with the immediate intervention to culprit injuries.

14.
J Theor Biol ; 364: 1-6, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25193285

RESUMO

Some spiders are well-known to mimic flowers or other plant surfaces in order to be cryptic to both their prey and their predators. We propose that dense, thread-like white trichomes of some plants from Estonia, Greece, Israel and Japan visually mimic spider webs, lepidopteran and spider-mite web nests and plant-pathogenic fungi, and that it may result in reduced herbivory, since various herbivores avoid spider- or other arthropod webs to circumvent predation or toxic attacks, or refrain from colonizing plants that have already been occupied by other herbivores and pathogens. Spiders and other web-forming arthropods are also the prey of certain vertebrate predators and wasps, and therefore such predators may be attracted to these web-like plant structures and prey on the invertebrate herbivores occupying them. We do not dismiss the possibility that these web-like structures may also have other defensive or physiological functions or that they are not classic mimics but rather exploit the herbivore׳s perceptual state concerning the avoidance of potentially risky objects.


Assuntos
Artrópodes/química , Herbivoria/fisiologia , Hifas/fisiologia , Plantas/anatomia & histologia , Seda/química , Tricomas/crescimento & desenvolvimento , Animais , Fungos/fisiologia , Modelos Biológicos , Tricomas/anatomia & histologia
15.
World J Clin Cases ; 2(9): 469-73, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25232553

RESUMO

Toxic epidermal necrolysis (TEN) is a severe adverse drug reaction, which is characterized by erythema, blisters, and/or erosions of the mucous membranes and skin, but intestinal involvement is rare. In contrast, pneumatosis cystoides intestinalis (PCI) is a rare condition associated with a wide variety of underlying diseases, but to date no patient has presented with PCI associated with TEN. A 55-year-old man was admitted to intensive care unit for treatment of TEN caused by phenobarbital. On day 8 after admission, he presented with progressive abdominal distention and hypotension. Computed tomography (CT) showed gas in the superior mesenteric vein and air filled cysts in the walls of the small intestine. He was suspected of having septic shock due to PCI. As there were no indications of bowel ischemia or necrosis, the patient was managed conservatively with antibiotics and oxygen therapy. On day 10 after admission, he was weaned off catecholamines, with CT on day 11 showing complete resolution of gas in the superior mesenteric vein and air filled cysts. To our knowledge, this article describes the first patient presenting with PCI associated with TEN.

16.
Korean J Anesthesiol ; 67(1): 52-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25097740

RESUMO

Unroofed coronary sinus (URCS) is a rare cardiac anomaly, in which communication occurs between the coronary sinus (CS) and the left atrium (LA) because of partial or complete absence of the CS roof. A 30-year-old woman was scheduled for surgical closure of atrial septal defect, mitral valve repair and tricuspid annuloplasty. The intraoperative transesophageal echocardiography (TEE) revealed left-to-right shunt between the CS and the LA. The three-dimensional (3D) TEE confirmed the diagnosis of partially URCS. This defect was repaired with a pericardial patch. In this case, the 3D images of URCS, which were a helpful supplement to the 2D images, providing better visualization of the wall defect and more information regarding the size and location of the defect. The combined use of 2D and 3D images provides valuable information to aid in understanding the anatomy and morphology of this rare anomaly.

18.
Circ J ; 78(2): 490-501, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24257136

RESUMO

BACKGROUND: A prior phase I/IIa clinical trial provided evidence for safety, feasibility and potential efficacy of i.m. injection of granulocyte colony-stimulating factor (G-CSF)-mobilized CD34+ cells in patients with critical limb ischemia (CLI). METHODS AND RESULTS: A phase II trial of CD34+ cell therapy was conducted in patients with CLI to explore endpoint selection and timing. No-option CLI patients (n=11) underwent i.m. transplantation of G-CSF-mobilized CD34+ cells isolated by magnetic sorting. Ischemic rest pain scales improved from week 2 vs. baseline (P<0.05). Skin perfusion pressure (P=0.0175), transcutaneous partial oxygen pressure (P=0.0446) and pain-free walking distance (P=0.0056) improved from week 2, total walking distance from week 8 (P=0.0182) and toe brachial pressure index from week 12 (P=0.0174) vs. baseline. These parameters peaked at week 36 or 52. Rutherford's category improved from week 24 vs. baseline (P=0.0065). CLI-free ratio serially increased and peaked (85.7%) at week 36. Serial change in Rutherford's category correlated with that in Rest Pain Scale (P=0.0374), but not with that in any physiological parameters. CONCLUSIONS: Ischemic rest pain scales and physiological parameters improved relatively early after cell therapy, then plateaued later accompanied by recovery from the CLI state. Rutherford's category and CLI-free ratio at week 36 or later may be suitable endpoints in cell therapy clinical trials for CLI. Functional parameters should be evaluated independently of such clinical endpoints for ischemia severity. ( CLINICAL TRIAL REGISTRATION: URL: https://dbcentre3.jmacct.med.or.jp/jmactr/Default.aspx. Unique identifier: JMA-IIA00022)


Assuntos
Antígenos CD34 , Isquemia , Extremidade Inferior , Manejo da Dor , Dor/fisiopatologia , Transplante de Células-Tronco , Células-Tronco , Adulto , Idoso , Autoenxertos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Feminino , Humanos , Isquemia/fisiopatologia , Isquemia/terapia , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/fisiopatologia , Masculino , Pessoa de Meia-Idade
19.
Masui ; 62(10): 1218-21, 2013 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-24228460

RESUMO

The perioperative management of pheochromocytoma is challenging for anesthesiologists and persistent hypotension secondary to cathecholamine depletion after tumor resection can be refractory to treatment. A 64-year-old man underwent right adrenalectomy for treatment of massive pheochromocytoma. Doxazosin administration was started and increased gradually to 12 mg daily. He was premedicated with doxazosin on the day of the surgery. Induction was uneventful but there was a sudden increase of blood pressure with tachycardia on handling of tumor which was controlled by intravenous remifentanil, landiolol, diltiazem, and magnesium sulfate. With dissection of the tumor, the blood pressure dropped to 65/40 mmHg, which was resistant to fluid and cathecholamine treatment. After commencement of low dose vasopressin administration (two boluses of 0.08 U followed by 1.6 U x hr(-1)), blood pressure gradually recovered to normal ranges. Low dose vasopressin can be safely used to treat postadrenalectomy hypotension and also can reduce the cathecholamine dose.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Hipotensão/tratamento farmacológico , Feocromocitoma/cirurgia , Vasopressinas/administração & dosagem , Adrenalectomia , Catecolaminas , Resistência a Medicamentos , Humanos , Hipotensão/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias
20.
J Anesth ; 27(5): 699-704, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23508279

RESUMO

PURPOSE: Left atrial enlargement correlates with the severity of diastolic dysfunction and is a predictor of cardiovascular complications such as atrial fibrillation. Aortic valve stenosis (AS) causes left atrial enlargement and progression of diastolic dysfunction. The aim of this study was to investigate the efficacy of the preoperative left atrial volume index (LAVI) in predicting postoperative outcome in patients with severe AS. METHODS: Forty-seven patients with severe AS who underwent aortic valve replacement were examined. Transthoracic echocardiography and LAVI measurement were performed on admission. Patients were divided into two groups according to optimal cut-off values of LAVI derived from receiver operating characteristic curves for postoperative atrial fibrillation (POAF) (group S: LAVI <52 ml/m(2), group L: LAVI ≥52 ml/m(2)). The incidence of POAF, ventilation time, inotropic support time, duration of stay in intensive care, and overall duration of hospital stay were evaluated. RESULTS: By univariate analysis, the incidence of POAF in group S was significantly lower than that in group L (25.9 and 65.0%, respectively; P < 0.01). Values for other parameters were higher in group L, although the differences were insignificant. CONCLUSION: In patients with severe AS, a preoperative LAVI of ≥52 ml/m(2) may be a useful predictor of POAF, although the efficacy of this index for predicting other postoperative outcomes has yet to be determined.


Assuntos
Estenose da Valva Aórtica/fisiopatologia , Valva Aórtica/fisiopatologia , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Coração/fisiopatologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ecocardiografia/métodos , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Átrios do Coração/cirurgia , Humanos , Incidência , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Período Pré-Operatório , Prognóstico , Curva ROC , Estudos Retrospectivos , Resultado do Tratamento
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