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2.
J Clin Med ; 13(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38892885

RESUMO

Background/Objectives: Bariatric surgery is a central cornerstone in obesity treatment. We aimed to assess the impact of diabetes on the postoperative outcomes of bariatric surgery and compare three techniques: sleeve gastrectomy, Roux-en-Y, and gastric banding. Methods: We extracted data from the National Inpatient Sample (2015-2019) using ICD codes. The primary outcome was postoperative mortality. Secondary outcomes were major bleeding, atrial fibrillation, and acute renal failure. Results: Among patients who underwent sleeve gastrectomy, diabetes was associated with a higher adjusted risk of mortality (aOR 2.07 [1.36-3.16]), atrial fibrillation, and acute renal failure, but a similar risk of bleeding. Among patients who underwent Roux-en-Y, diabetes did not increase mortality and bleeding risk. Still, it was associated with a higher risk of atrial fibrillation and acute renal failure. Among patients who underwent gastric banding, diabetes was only associated with a higher risk of bleeding. When comparing the three techniques in diabetes patients, Roux-en-Y was significantly associated with higher mortality and acute renal failure risk when compared to the other procedures. Bleeding was more common in Roux-en-Y than in Sleeve. Conclusions: In total, diabetes is associated with worse postoperative outcomes in bariatric surgery, regardless of the technique. Among diabetes patients, Roux-en-Y was associated with the highest mortality and morbidity.

3.
Ann Med Surg (Lond) ; 86(5): 3029-3035, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38694384

RESUMO

Introduction and importance: Brentuximab vedotin (BV) is an anti-CD30 antibody approved for various cancers, including refractory Hodgkin lymphoma (HL), anaplastic large-cell lymphoma (ALCL) among others. In general, BV has been found to be well-tolerated, with the most frequently reported side effects being peripheral neuropathy and neutropenia. BV-induced pneumonitis is extremely rare. To the best of our knowledge, this is the sixth reported instance of BV-induced lung toxicity. Case presentation: This case presents a female patient in her forties diagnosed with cutaneous T-cell lymphoma undergoing BV treatment. She developed acute hypoxic respiratory failure, ultimately, underwent a diagnostic evaluation including a computed tomography (CT) scan, which showed bilateral airspace consolidations and ground-glass opacities, suggestive of organizing pneumonia and diffuse alveolar damage. Bronchoscopy with bronchoalveolar lavage and transbronchial biopsy ruled out infection, and pulmonary lymphoma and confirmed the diagnosis of BV-induced pneumonitis. The patient had significant clinical improvement after stopping the offending agent, and starting steroids, with optimal clinical recovery at 8 weeks follow-up. Clinical discussion: Drug-related pneumonitis poses a significant concern in the management of cancer patients. Numerous chemotherapeutic agents, such as bleomycin, cyclophosphamide, methotrexate, thalidomide, and others, have been associated with pulmonary-related toxicities. These adverse effects primarily stem from direct toxicity or immunosuppression-related infections. Less commonly, immune-mediated injury may occur. Conclusion: Physicians must have a high index of suspicion for BV-induced pneumonitis, hence, early recognition with subsequent holding of the causative agent, initiation of immunosuppression with steroids, and occasionally steroid-sparing medications, prevent an otherwise fatal outcome.

4.
Cureus ; 16(4): e59041, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38800238

RESUMO

Epidural anesthesia (EA) involves reaching the spinal epidural space with an anesthetic drug injection. This procedure provides pain relief during labor. Although EA can lead to some complications, subdural hemorrhage (SDH) is a rare adverse event associated with it. We report the case of a 25-year-old female patient who presented to our emergency department with a one-month history of headaches and associated blurred vision following a normal vaginal delivery with EA. She was initially treated as a case of post-dural puncture headache (PDPH), with no improvement. Finally, the diagnosis of bilateral SDH was made based on a brain MRI. She required surgical intervention, which led to a positive prognosis and a full return of normal baseline neurological functions. Only a few reports in the literature have indicated the possibility of cranial subdural hematoma formation associated with spinal or epidural analgesia. Our patient experienced a delay in her diagnosis and treatment, as SDH following EA is a rare entity. It is important to follow up with such patients and consider other possibilities when symptoms fail to resolve. Also, reporting these cases is crucial to assist clinicians in early diagnosis and treatment, and to avoid disastrous outcomes.

5.
An Acad Bras Cienc ; 85(3): 1073-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23969852

RESUMO

Mushrooms possess nutritional and medicinal properties that have long been used for human health preservation and that have been considered by researchers as possible sources of free radical scavengers. In this work, the antioxidant properties of water extracts from Agaricus blazei Murill, produced by maceration and decoction, are demonstrated in vitro. Resistance to oxidation is demonstrated through three mechanisms: i) inhibition of enzymatic oxidative process, with 100% inhibition of HRP (horseradish peroxidase) and MPO (myeloperoxidase); ii) inhibition of cellular oxidative stress, with 80% inhibition of the oxidative burst of polymorphonuclear neutrophils (PMNs); and iii) direct action over reactive species, with 62% and 87% suppression of HOCl and superoxide anion radical (O2• -), respectively. From the data, it was concluded that the aqueous extract of A. blazei has significant antioxidant activity, indicating its possible application for nutraceutical and medicinal purposes.


Assuntos
Agaricus/química , Antioxidantes/farmacologia , Neutrófilos/enzimologia , Oxirredução , Agaricus/enzimologia , Antioxidantes/isolamento & purificação , Sequestradores de Radicais Livres , Luminescência , Estresse Oxidativo , Peroxidase/metabolismo , Fatores de Tempo
6.
Cureus ; 15(5): e39554, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37378113

RESUMO

Thyroid abscess is a rare but potentially serious condition that can affect young females. It is characterized by a localized collection of pus within the thyroid gland, often resulting from a bacterial infection. The occurrence of thyroid abscesses is a rare complication even in immune-compromised individuals. Nevertheless, when they do occur, they can present with symptoms such as neck swelling, pain, fever, and other systemic manifestations. The diagnostic tool of choice for thyroid abscess is ultrasound, and the mainstay of treatment involves a combination of abscess drainage and antibiotics. In this case report, we describe the case of an 11-year-old girl who presented with neck swelling and pain and was subsequently diagnosed with thyroid abscess. The patient was successfully managed with incision and drainage, followed by a course of antibiotics.

7.
Cureus ; 15(5): e39254, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37342730

RESUMO

Pulmonary alveolar proteinosis (PAP) is an extremely rare pulmonary disease that can be classified into primary, secondary, or congenital types. It typically presents with a pattern of interstitial lung disease. This rare condition is even rare in the adolescent or pediatric age group, making this case particularly rare and interesting. We report a case of a 15-year-old girl who presented with a four-month history of dry cough and exertional dyspnea. After performing a high-resolution computed tomography (HRCT) scan and bronchoalveolar lavage (BAL) with analysis of the BAL fluid, she was eventually diagnosed with PAP. She was then referred to a higher qualified center, where a whole lung lavage (WLL) was performed, resulting in significant improvement of her symptoms.

8.
Ann Med Surg (Lond) ; 85(7): 3634-3637, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37427231

RESUMO

Cardiac tumors are a rare condition that typically presents with nonspecific symptoms. Among the histologic patterns, myxoid sarcomas are rarely identified and may have a less favorable prognosis. Reporting a case of this type of cardiac tumor can increase awareness about this condition and aid in early diagnosis, potentially leading to better outcomes. Case presentation: We are presenting a case of a 41-year-old female with left atrial myxoid sarcoma, which was presented with a cardiogenic shock picture. She underwent surgical excision of the mass and was discharged in good condition. After discharge, she deteriorated and was found to have lung metastases. Clinical discussion: Primary cardiac sarcomas, due to their rarity and poor prognosis, are often diagnosed at an advanced stage of the disease and lack sufficient data to establish a standard course of treatment. The cornerstone of therapy is surgical resection. However, novel therapeutic approaches must be developed. Conclusions: Primary cardiac tumors should be suspected in adult patients with progressive dyspnea, and a biopsy should also be done to determine the histopathological pattern of the mass and estimate the overall prognosis and outcomes.

9.
Adv Med Educ Pract ; 14: 973-981, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37701425

RESUMO

Purpose: During the COVID-19 pandemic, teaching has required online-learning modalities to facilitate easily accessible yet high-quality education. However, since the nature of anatomy requires hands-on experience in laboratories with cadavers, teaching anatomy in an online setting has proven especially difficult. This matter may be resolved with the Anatomage Table, an advanced anatomy visualization tool, which several studies have suggested can augment learning experiences for students in anatomy courses. Our objective was to provide accessible online modules, through utilization of the Anatomage Table, for medical students to facilitate their learning and enhance online learning experience. Materials and Methods: Ten modules were designed, consisting of a presentation, a pre- and post-self-assessment, as well as anatomical images and radiographs taken from Anatomage Table. The modules were based on a single organ system, and a clinical case pertaining to that organ system was presented. Weill Cornell Medicine-Qatar (WCM-Q) second-year medical students contributed 102 responses in total throughout the 10 modules. Using a paired t-test, the study compared the students' pre- and post-assessment scores to determine how beneficial the modules were. Results: A significant difference in scores on the pre- and post-assessments was found for all 10 modules using a paired t-test. At the end of the modules, the students completed a feedback survey to assess the quality and convenience. Most of the students agreed or strongly agreed that the modules were beneficial to their online anatomy learning and wanted to see similar anatomical modules in the future. Conclusion: The Anatomage Table is an innovative virtual resource that can significantly contribute to a more engaging and productive experience for medical students.

10.
Cureus ; 15(9): e46112, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37900396

RESUMO

Cardiac myxomas are the most common primary cardiac neoplasms, with only a small percentage being found in the left ventricle. Herein, we describe a 25-year-old male who presented with a complaint of chest pain for almost three months and was found to have a 2x2 cm encapsulated tumor attached by a 2-3 mm stalk to the mid-septum, 5 cm below the aortic annulus, via echocardiography. Additionally, a chest CT angiography was performed and revealed a small defect in the left ventricle with a low attenuation density originating from the septum. The tumor was later managed surgically with a median sternotomy approach, and left ventricular myxoma was confirmed histopathologically. Even though cardiac myxomas are incredibly uncommon, they are usually located in the left and right atria and are very unlikely to present in the left ventricle. This incident highlights the importance of taking cardiac myxoma into account as a potential differential diagnosis in cases of chest pain to prevent any further complications.

11.
Cureus ; 15(12): e49958, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38179378

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease that can cause various health problems, including issues with the blood. One common blood-related symptom in SLE is immune thrombocytopenia (ITP), which leads to low platelet counts. In some cases, SLE patients with ITP may develop a rare but serious complication called subdural hematoma (SDH), which is a type of bleeding in the brain. This combination of conditions can be challenging to manage and has a high mortality rate. In a specific case, a 14-year-old girl with chronic ITP developed a sudden headache and was diagnosed with childhood-onset SLE, leading to the development of SDH. The treatment plan had to be adjusted, and a splenectomy was considered. It's important to be aware of the association between SLE, ITP, and SDH, especially in pediatric patients, and to conduct appropriate investigations in cases of severe headaches, to rule out life-threatening causes.

12.
Hum Vaccin Immunother ; 19(1): 2167410, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36915960

RESUMO

Despite widespread mass rollout programs, the rapid spread of the SARS-CoV-2 Omicron variant called into question the effectiveness of the existing vaccines against infection, hospitalization, severity, and mortality compared to previous variants. This systematic review summarizes and compares the effectiveness of the COVID-19 vaccines, with respect to the above outcomes in adults, children, and adolescents. A comprehensive literature search was undertaken on several databases. Only 51 studies met our inclusion criteria, revealing that the protection from primary vaccination against Omicron infection is inferior to protection against Delta and Alpha infections and wanes faster over time. However, mRNA vaccine boosters were reported to reestablish effectiveness, although to a lower extent against Omicron. Nonetheless, primary vaccination was shown to preserve strong protection against Omicron-associated hospitalization, severity, and death, even months after last dose. However, boosters provide more robust and longer-lasting protection against hospitalizations due to Omicron as compared to only primary series.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adolescente , Adulto , Criança , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Hospitalização
13.
J Smok Cessat ; 2022: 1879270, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159221

RESUMO

Introduction: To find genetic variants in the DRD4 and HTR2A genes' promoter regions and exons that are associated with tobacco smoking and nicotine addiction in Egyptian university students as well as to study the association between personality traits and smoking status. Methods: A self-administered questionnaire about cigarette smoking and personality attributes (Big Five Inventory, ESPAD Questionnaire on Substance Abuse, and Buss-Perry Aggression Questionnaire). The participants in the study were 90 nonsmokers (NS) and 88 current smokers (CS), who were divided into two groups depending on their cigarette consumption per day (cpd): 55 heavy smokers (HS, >20 cpd) and 33 light smokers (LS, 1-10 cpd). Four and eight single nucleotide polymorphisms (SNPs) in the DRD4, HTR2A, and MOA genes, respectively, were genotyped. Results: Smokers scored lower on neuroticism, agreeableness, conscientiousness, openness, and extraversion than nonsmokers, but higher on aggression. Furthermore, the C allele of rs1800955 in DRD4 was associated with cigarette smoking in the HS vs. NS and LS vs. NS studies. The T allele of the HTR2A rs6313 gene was discovered to be strongly associated with cigarette smoking. There was no link discovered between MOA rs1137070 and MOA rs1137070. Conclusions: Using a comprehensive personality model (FFM), this study repeats and extends earlier research. Personality and genetic studies may aid in the development of a more complete and conclusive understanding of cigarette smoking, as well as more precise policies and guidelines for smoking cessation and quitting.

14.
PLoS One ; 15(10): e0241179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33108373

RESUMO

INTRODUCTION: In Switzerland, a nationwide Swiss Diagnosis related Groups (Swiss DRG) system for hospital reimbursement was introduced in 2012. However, the impact of DRG systems on primary care is still unclear with respect to number of consultations and costs. The aim of this study was to investigate the effect of the implementation of DRG on costs and volumes in the primary care sector, on a nationwide basis in Switzerland. METHODS: The study retrospectively analysed yearly data, from 2008 to 2014, of almost 60 Swiss health insurers that covered almost all Swiss general practitioners, with a total number of patients which represented approximately 76% of the Swiss population. GP consultations, total numbers and rates, and the relative costs reimbursed (TARMED tariff values) in the Swiss federal states, cantons, which already introduced a DRG-like system before 2012 (AP-DRG), were compared to the GP consultations and costs reimbursed in the other cantons (DRG-naive). Regression discontinuity design analysis and mixed regression models, at cantonal level, were performed to evaluate the effect of the nationwide implementation of the Swiss DRG on health care demand and costs in the primary care setting. Change in outcome level and yearly trend pattern difference between groups (AP-DRG vs. DRG-naive) were examined. RESULTS: Overall, the total number of GP consultations and the relative TARMED values increased from 2008 to 2014. In the DRG naive, 15 cantons: in 2008, the number of GP consultations were 13,114,126, with a TARMED value of 1,194,957,157 CHF, and in 2014, the GP consultation were 13,752,511, with a TARMED value of 1,513,861,260 CHF. In the AP-DRG group, 11 cantons, the total number of GP consultations increased from 8,787,646, in 2008, to 9,347,168 in 2014 and the TARMED value increased from 896,673,657 CHF in 2008, to 1,100,203,508 CHF in 2014. The yearly trend pattern of GP consultations and TARMED values, in the AP-DRG group, were not significantly different from the respective trends in the DRG- naive and, overall, no significant change was detected in consultations and costs trends before and after 2012. DISCUSSION/CONCLUSION: This study found no evidence of any effect of the introduction of the SwissDRG on the yearly trend of primary care consultations and costs. Nevertheless, potential negative impacts on vulnerable patients, as chronically ill patients, could not be excluded and further investigation is required.


Assuntos
Doença Crônica/economia , Custos e Análise de Custo , Grupos Diagnósticos Relacionados/organização & administração , Custos de Cuidados de Saúde , Hospitalização/economia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Atenção Primária à Saúde/economia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Doença Crônica/epidemiologia , Doença Crônica/terapia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados não Aleatórios como Assunto , Estudos Retrospectivos , Suíça/epidemiologia , Adulto Jovem
15.
Int Angiol ; 38(6): 466-473, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31580041

RESUMO

BACKGROUND: Chronic mesenteric ischemia (CMI) is a rare, but potentially fatal condition, which is becoming increasingly prevalent in elderly patients. This study investigated the impact of endovascular intervention on patient symptomology and the influence of extent of mesenteric disease on patient morbidity and mortality. METHODS: All patients who underwent primary angioplasty (±stenting) to the mesenteric vessels for CMI between July 2008 to July 2017 were retrospectively identified. Patient data relating to comorbidities, clinical presentation, disease burden, procedural details, symptomatology, reintervention and mortality were collected. Mortality was assessed using regression analysis, which was adjusted for age and gender. RESULTS: Overall, 38 patients were included in the study. The median age was 73.5 years (interquartile range, 70.0-77.8). Abdominal pain (N.=36), postprandial pain (N.=32) and weight loss (N.=32) were the most common symptoms reported at presentation. Technical success was achieved in 37 patients. Thirty-two patients were symptom free at 6 weeks and 29 patients were symptom free at 2 years. Overall 5 patients required reintervention. At 30 days and 2 years one and seven patients were deceased, respectively. Significant association was observed between three vessel intervention and overall mortality (adjusted odds ratio 14.5, 95% confidence interval: 1.28-165.86, P=0.031). Majority of patients died of a cause unrelated to their CMI. CONCLUSIONS: Endovascular intervention for CMI is safe and provides satisfactory short-term and intermediate term symptom resolution in majority of patients. This study supports the routine use of endovascular intervention in the management of this complex disease.


Assuntos
Angioplastia com Balão , Isquemia Mesentérica/terapia , Stents , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Isquemia Mesentérica/mortalidade , Isquemia Mesentérica/fisiopatologia , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Reino Unido , Grau de Desobstrução Vascular
16.
J Biomed Opt ; 11(5): 054029, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17092178

RESUMO

We used the effect of temperature on the localized reflectance of human skin to assess the role of noise sources on the correlation between temperature-induced fractional change in optical density of human skin (DeltaOD(T)) and blood glucose concentration [BG]. Two temperature-controlled optical probes at 30 degrees C contacted the skin, one was then cooled by -10 degrees C; the other was heated by +10 degrees C. DeltaOD(T) upon cooling or heating was correlated with capillary [BG] of diabetic volunteers over a period of three days. Calibration models in the first two days were used to predict [BG] in the third day. We examined the conditions where the correlation coefficient (R2) for predicting [BG] in a third day ranked higher than R2 values resulting from fitting permutations of randomized [BG] to the same DeltaOD(T) values. It was possible to establish a four-term linear regression correlation between DeltaOD(T) upon cooling and [BG] with a correlation coefficient higher than that of an established noise threshold in diabetic patients that were mostly females with less than 20 years of diabetes duration. The ability to predict [BG] values with a correlation coefficient above biological and body-interface noise varied between the cases of cooling and heating.


Assuntos
Artefatos , Glicemia/análise , Glicemia/metabolismo , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/fisiopatologia , Fotometria/métodos , Pele/fisiopatologia , Adolescente , Adulto , Idoso , Temperatura Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Am J Infect Control ; 43(8): e39-41, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26234221

RESUMO

In a retrospective study about the epidemiology of exposure to bloodborne pathogens among health care providers, 71.10% of the analyzed events occurred among health professionals, mainly auxiliary nurses. Percutaneous exposure (83.04%) was the most frequent. Greater advances are necessary in the development of public policies for this issue in terms of inspection of regulatory norms and raising the professionals' awareness through policy and education.


Assuntos
Patógenos Transmitidos pelo Sangue , Pessoal de Saúde , Ferimentos Penetrantes Produzidos por Agulha/epidemiologia , Exposição Ocupacional , Adulto , Brasil/epidemiologia , Educação Médica , Feminino , Humanos , Controle de Infecções/métodos , Masculino , Pessoa de Meia-Idade , Ferimentos Penetrantes Produzidos por Agulha/prevenção & controle , Estudos Retrospectivos , Adulto Jovem
18.
J Biomed Opt ; 8(3): 534-44, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12880361

RESUMO

We observed a difference in the thermal response of localized reflectance signal of human skin between type 2 diabetics and nondiabetics. We investigated the use of this thermo-optical behavior as the basis for a noninvasive method for the determination of the diabetic status of a subject. We used a two-site temperature differential method, which is predicated upon the measurement of localized reflectance from two areas on the surface of the skin. Each of these areas is subjected to a different thermal perturbation. The response of localized reflectance to temperature perturbation was measured and used in a classification algorithm. We used a discriminant function to classify subjects as diabetic or nondiabetic. In a prediction set of twenty-four noninvasive tests collected from six diabetic and six nondiabetic subjects, the sensitivity ranged between 73 and 100%, and the specificity ranged between 75 and 100%, depending on the thermal conditions and the probe-skin contact time. The difference in the thermo-optical response of the skin of the two groups is explained in terms of a difference in the response of cutaneous microcirculation, which is manifested as a difference in the near-infrared light absorption. Another factor is the difference in the temperature response of the scattering coefficient between the two groups, which may be caused by cutaneous structural differences induced by nonenzymatic glycation of skin protein fibers, and possibly by the difference in blood cell aggregation.


Assuntos
Temperatura Baixa , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Diagnóstico por Computador/métodos , Temperatura Alta , Temperatura Cutânea/efeitos da radiação , Espectrofotometria Infravermelho/métodos , Algoritmos , Antebraço/efeitos da radiação , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura , Tomografia Óptica/métodos
19.
J Biomed Opt ; 8(2): 191-205, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12683845

RESUMO

We determine temperature effect on the absorption and reduced scattering coefficients (mu(a) and mu(s)(')) of human forearm skin. Optical and thermal simulation data suggest that mu( a) and mu(s)(') are determined within a temperature-controlled depth of approximately 2 mm. Cutaneous mu(s)(') change linearly with temperature. Change in mu(a) was complex and irreversible above body normal temperatures. Light penetration depth (delta) in skin increased on cooling, with considerable person-to-person variations. We attribute the effect of temperature on mu(s)(') to change in refractive index mismatch, and its effect on mu(a) to perfusion changes. The reversible temperature effect on mu (s)(' ) was maintained during more than 90 min. contact between skin and the measuring probe, where temperature was modulated between 38 and 22 degrees C for multiple cycles While temperature modulated mu(s)(' ) instantaneously and reversibly, mu(a) exhibited slower response time and consistent drift. There was a statistically significant upward drift in mu(a) and a mostly downward drift in mu( s)(') over the contact period. The drift in temperature-induced fractional change in mu(s)(') was less statistically significant than the drift in mu(s)('). Deltamu( s)(') values determined under temperature modulation conditions may have less nonspecific drift than mu(s)(') which may have significance for noninvasive determination of analytes in human tissue.


Assuntos
Luz , Modelos Biológicos , Fenômenos Fisiológicos da Pele/efeitos da radiação , Pele/efeitos da radiação , Temperatura , Tomografia Óptica/métodos , Absorção , Simulação por Computador , Relação Dose-Resposta à Radiação , Antebraço/patologia , Antebraço/fisiologia , Antebraço/efeitos da radiação , Temperatura Alta , Humanos , Raios Infravermelhos , Imagens de Fantasmas , Espalhamento de Radiação , Pele/citologia , Temperatura Cutânea/fisiologia , Temperatura Cutânea/efeitos da radiação
20.
Diabetes Technol Ther ; 6(5): 660-97, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15628820

RESUMO

There are three main issues in non-invasive (NI) glucose measurements: namely, specificity, compartmentalization of glucose values, and calibration. There has been progress in the use of near-infrared and mid-infrared spectroscopy. Recently new glucose measurement methods have been developed, exploiting the effect of glucose on erythrocyte scattering, new photoacoustic phenomenon, optical coherence tomography, thermo-optical studies on human skin, Raman spectroscopy studies, fluorescence measurements, and use of photonic crystals. In addition to optical methods, in vivo electrical impedance results have been reported. Some of these methods measure intrinsic properties of glucose; others deal with its effect on tissue or blood properties. Recent studies on skin from individuals with diabetes and its response to stimuli, skin thermo-optical response, peripheral blood flow, and red blood cell rheology in diabetes shed new light on physical and physiological changes resulting from the disease that can affect NI glucose measurements. There have been advances in understanding compartmentalization of glucose values by targeting certain regions of human tissue. Calibration of NI measurements and devices is still an open question. More studies are needed to understand the specific glucose signals and signals that are due to the effect of glucose on blood and tissue properties. These studies should be performed under normal physiological conditions and in the presence of other co-morbidities.


Assuntos
Glicemia/análise , Calibragem , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Humanos , Hiperglicemia/sangue , Microcirculação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Pele/irrigação sanguínea , Estados Unidos , United States Food and Drug Administration
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