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1.
Qual Life Res ; 32(5): 1427-1446, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36441383

RESUMO

BACKGROUND: Clinical data on the modern topic fasting among cancer patients are rare. This review aimed to summarise published clinical data on fasting and its effects on patients undergoing chemotherapy and therefore to give some directions in advising patients with the desire to fast. METHOD: A systematic search was conducted searching five electronic databases (Embase, Cochrane, PsychInfo, CINAHL and Medline) to find studies concerning the use, effectiveness and potential harm of fasting during therapy on cancer patients. The main endpoints were quality of life, side effects and toxicities of the fasting intervention. RESULTS: The search results totaled 3983 hits. After systematic sorting according to standardised pre-defined criteria, nine publications which covered eight studies with 379 patients were included in this systematic review. The majority of the patients included were diagnosed with breast- and gynaecological cancers. Fasting duration and timepoints ranged significantly (24-140 h before, and on the day of, chemotherapy to 56 h after chemotherapy). In one study patients were fasting before cancer surgery. The studies were mostly low to moderate quality and reported heterogeneous results. Overall, the studies were insufficiently powered to detect significant effects on the predefined endpoints. CONCLUSION: Fasting for short periods does not have any beneficial effect on the quality of life of cancer patients during treatment. Evidence on fasting regimes reducing side effects and toxicities of chemotherapy is missing. In contrast, as the negative effects of unintentional weight loss are known to impact clinical outcomes severely, fasting is not indicated in this context.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Qualidade de Vida/psicologia , Neoplasias/tratamento farmacológico , Jejum
2.
Sci Rep ; 12(1): 2907, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35190584

RESUMO

Physical activity (PA) helps prevention and aftercare of sporadic breast cancer (BC), cardiopulmonary fitness (CPF) being an age-independent predictor of tumor-specific mortality. Therefore, we wanted to identify predictors of CPF (represented by peak oxygen uptake: VO2peak) in BRCA1/2 mutation carriers whose risk of developing BC is high. We used cross-sectional data from 68 BRCA1/2 germline mutation carrying women participating in the randomized, prospective, controlled clinical study LIBRE-1. Assessments included cardiopulmonary exercise testing, medical and lifestyle history plus socioeconomic status. Additionally, the participants completed a psychological questionnaire regarding their attitude, subjective norms, perceived behavior control and intention towards PA. A multivariate logistic regression model was used to identify predictors for participants reaching their age- and sex-adjusted VO2peak reference values. 22 participants (median age: 40 years, interquartile range (IQR) 33-46) were cancer-unaffected and 46 cancer-affected (median age: 44 years, IQR 35-50). The strongest predictor for reaching the reference VO2peak value was attitude towards PA (Odds Ratio 3.0; 95% Confidence Interval 1.3-8.4; p = 0.021). None of the other predictors showed a significant association. A positive attitude towards PA seems to be associated with VO2peak, which should be considered in developing therapeutic and preventive strategies.Trial registrations: NCT02087592; DRKS00005736.


Assuntos
Atitude Frente a Saúde , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/prevenção & controle , Teste de Esforço , Exercício Físico/psicologia , Mutação em Linhagem Germinativa , Consumo de Oxigênio , Adulto , Neoplasias da Mama/etiologia , Neoplasias da Mama/psicologia , Estudos Transversais , Feminino , Heterozigoto , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários
3.
J Comp Pathol ; 174: 39-53, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31955802

RESUMO

Members of the chloride channel regulator, calcium-activated (CLCA) family are considered to be modifiers in inflammatory, mucus-based respiratory conditions such as asthma and cystic fibrosis. Previous work has shown substantial differences between human and murine CLCA orthologues that limit the value of mouse models. As an alternative, the cat is an unfamiliar but powerful model of human asthma. We therefore characterized the expression profiles of CLCA proteins in the feline respiratory tract. Identical to other species, the feline CLCA1 protein was immunohistochemically localized to virtually all goblet cells and found to be secreted into the mucus. However, it was not detected in submucosal glands where it is expressed in other species. In contrast to all other species studied to date, feline CLCA2 was not found in submucosal glands or any other airway cells. Similar to mice, but in contrast to man and pigs, the feline respiratory tract was devoid of CLCA4 expression. In the airways of asthmatic cats, CLCA1 was strongly overexpressed, similar to human patients. Therefore, despite some similarities in CLCA1 protein expression and secretion, substantial differences were identified between several feline CLCA family members and their respective orthologues in man, mice and pigs, which must be considered in comparative medicine.


Assuntos
Gatos , Canais de Cloreto , Sistema Respiratório , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Suínos
5.
Eur J Cancer Care (Engl) ; 27(4): e12855, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29767834

RESUMO

In order to quantify gaps in the provision of medical nutrition care in Germany and pinpoint specific areas of need, we collected data from patients, nurses and physicians. The results from the patient survey were published separately. A total of 506 participants from 69 certified centers answered the questions developed in cooperation with representatives from different professional groups (physicians, nurses and dietitians). Only about a third of participants reported that their institution provides structured pathways to nutritional counseling. 70.1% of those physicians reported that there was a specialist in nutrition available at their center while only 55.8% of nurses agreed. Only a quarter (24.2% and 26.9%) of physicians and nurses reported that their institution provided continuation of nutrition care after dismissal. A gap exists between need and consistent delivery of nutrition care services. Structured nutrition care pathways provided by legally certified nutrition professionals pathways are lacking. Cancer organizations may support this process by requiring documented nutrition care pathways and provision of services on a need based system into guidelines and certification criteria.


Assuntos
Acessibilidade aos Serviços de Saúde , Neoplasias/terapia , Enfermeiras e Enfermeiros , Terapia Nutricional/estatística & dados numéricos , Médicos , Alemanha , Humanos , Inquéritos e Questionários
6.
Clin Nutr ; 36(5): 1187-1196, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28689670

RESUMO

Patients with cancer are at particularly high risk for malnutrition because both the disease and its treatments threaten their nutritional status. Yet cancer-related nutritional risk is sometimes overlooked or under-treated by clinicians, patients, and their families. The European Society for Clinical Nutrition and Metabolism (ESPEN) recently published evidence-based guidelines for nutritional care in patients with cancer. In further support of these guidelines, an ESPEN oncology expert group met for a Cancer and Nutrition Workshop in Berlin on October 24 and 25, 2016. The group examined the causes and consequences of cancer-related malnutrition, reviewed treatment approaches currently available, and built the rationale and impetus for clinicians involved with care of patients with cancer to take actions that facilitate nutrition support in practice. The content of this position paper is based on presentations and discussions at the Berlin meeting. The expert group emphasized 3 key steps to update nutritional care for people with cancer: (1) screen all patients with cancer for nutritional risk early in the course of their care, regardless of body mass index and weight history; (2) expand nutrition-related assessment practices to include measures of anorexia, body composition, inflammatory biomarkers, resting energy expenditure, and physical function; (3) use multimodal nutritional interventions with individualized plans, including care focused on increasing nutritional intake, lessening inflammation and hypermetabolic stress, and increasing physical activity.


Assuntos
Desnutrição/diagnóstico , Desnutrição/terapia , Neoplasias/terapia , Composição Corporal , Índice de Massa Corporal , Dieta , Exercício Físico , Custos de Cuidados de Saúde , Humanos , Avaliação Nutricional , Necessidades Nutricionais , Estado Nutricional , Apoio Nutricional , Prevalência , Terminologia como Assunto
7.
Med Oncol ; 34(5): 72, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28353094

RESUMO

The efficacy and benefits of ketogenic diets (KD) have recently been gaining worldwide and remain a controversial topic in oncology. This systematic review therefore presents and evaluates the clinical evidence on isocaloric KD dietary regimes and reveals that evidence supporting the effects of isocaloric ketogenic dietary regimes on tumor development and progression as well as reduction in side effects of cancer therapy is missing. Furthermore, an array of potential side effects should be carefully considered before applying KD to cancer patients. In regard to counseling cancer patients considering a KD, more robust and consistent clinical evidence is necessary before the KD can be recommended for any single cancer diagnosis or as an adjunct therapy.


Assuntos
Dieta Cetogênica/métodos , Neoplasias/dietoterapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Int J Clin Oncol ; 22(1): 200-206, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27485457

RESUMO

PURPOSE: Cancer patients represent a patient group with a wide-range of nutrition related problems which are often under-recognized and undertreated. In order to assess the status quo of nutritional care in Germany, we conducted a survey among patients with different types of cancer. METHODS: A standardized questionnaire was distributed online by two national umbrella organizations for self-help groups. RESULTS: 1335 participants completed the questionnaire. 69 % of the participants reported having received information on nutrition and/or specific nutrition-related symptoms. Most often this information was derived from print media (68.5 %) or from within self-help groups (58.7 %). 57.0 % of participants reported having had questions concerning nutrition and/or problems with food intake. most frequently named topics of interest were "healthy diet" (35.0 %) weakness/fatigue (24.3 %), dietary supplements (21.3 %) and taste changes (19.8 %). Nutrition information was most often provided by dietitians (38.7 %) followed by physicians (9.8 %). Women reported receiving nutrition counseling in the hospital nearly twice as often as men (12.5 % versus 5.7 %; p < 0.001). A quarter of the patients (24.1 %) reported using dietary supplements and patients who had received some sort of nutrition information more often reported using supplements (p < 0.001). CONCLUSION: Nutrition is an essential element in cancer care and patients report a high interest and need: Yet, many patients do not have access to high quality nutrition therapy during and after cancer therapy. IMPLICATIONS FOR CANCER SURVIVORS: With respect to survival and quality of life, increasing the availability and resources for provision of evidence based nutrition information seems mandatory.


Assuntos
Dieta , Neoplasias/terapia , Apoio Nutricional , Educação de Pacientes como Assunto , Adulto , Idoso , Idoso de 80 Anos ou mais , Suplementos Nutricionais , Aconselhamento Diretivo , Fadiga/etiologia , Feminino , Alemanha , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Neoplasias/complicações , Avaliação Nutricional , Estado Nutricional , Qualidade de Vida , Fatores Sexuais , Distúrbios do Paladar/etiologia
9.
Appl Opt ; 54(35): 10494-7, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26836876

RESUMO

Measurements of the frequency stability of a far-infrared molecular laser have been made by mixing the harmonic of an ultrastable microwave source with a portion of the laser output signal in a terahertz (THz) Schottky diode balanced mixer. A 3 GHz difference-frequency signal was used in a frequency discriminator circuit to lock the laser to the microwave source. Comparisons of the short- and long-term laser frequency stability under free-running and locked conditions show a significant improvement with locking. Short-term frequency jitter was reduced by an order of magnitude, from approximately 40 to 4 kHz, and long-term drift was reduced by more than three orders of magnitude, from approximately 250 kHz to 80 Hz. The results, enabled by the efficient Schottky diode balanced mixer downconverter, demonstrate that ultrastable microwave-based frequency stabilization of THz optically pumped lasers (OPLs) will now be possible at frequencies extending well above 4.0 THz.

10.
Biochim Biophys Acta ; 1526(1): 5-9, 2001 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-11287115

RESUMO

A method has been devised for the quantitative analysis of cyanophycin, based on (1)H nuclear magnetic resonance (NMR) spectroscopy, allowing determination of the nitrogen status of cyanobacteria. Cyanophycin is extracted with minimal washing from small volumes of cells and quantified by integration of the NMR peak attributed to the protons attached to the delta-carbon of arginine. Linear relationships were found between the amount of cyanophycin determined by this method and both known concentrations of cyanophycin solutions and the amount of cyanophycin determined using the standard chemical arginine assay.


Assuntos
Cianobactérias/química , Proteínas de Plantas/análise , Proteínas de Bactérias , Espectroscopia de Ressonância Magnética , Proteínas de Plantas/isolamento & purificação , Reprodutibilidade dos Testes
11.
J Chromatogr B Biomed Appl ; 685(2): 370-4, 1996 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-8953182

RESUMO

A high-performance liquid chromatography procedure for detection and quantitation of ethylene glycol in serum is described. Ethylene glycol and internal standard are derivatized with benzoyl chloride under alkaline conditions, purified by solid-phase extraction and analyzed by HPLC with UV detection. Analytical recovery of ethylene glycol ranges between 96 and 103%. The calibration curve is linear from 20 to 2000 mg/l. The limits of detection and quantitation are 10 and 20 mg/l, respectively. Assay imprecision is 4.8% or less. The assay is free from common interferences and provides increased sensitivity, improved precision and extended linearity.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Etilenoglicóis/sangue , Animais , Benzoatos/química , Calibragem , Bovinos , Etilenoglicóis/química , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
12.
Arch Otolaryngol Head Neck Surg ; 121(7): 790-4, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7598859

RESUMO

OBJECTIVE: To determine the clinical and prognostic significance of chromosome 11q13 amplification in squamous cell carcinoma of the head and neck. DESIGN: Retrospective clinical analysis. SETTING: University and private cancer centers. PATIENTS: Fifty-six patients with pathologically confirmed head and neck squamous cell carcinoma whose tumors had been assayed for the presence or absence of chromosome 11q13 amplification. MEASUREMENTS: The degree of DNA amplification in each tumor was determined using chromosome 11q13 probes for the bcl-1 major translocation cluster, PRAD1/cyclin D1 (CCND1), the fibroblast growth factor gene HST1, EMS1, and glutathione-S-transferase-pi-1. The presence or absence of amplification in each patient was correlated with primary site, tumor stage, nodal status, presence or absence of distant metastasis, disease recurrence, time to recurrence, clinical outcome (disease status), and overall survival. RESULTS: Amplification of chromosome 11q13 was identified in 39% (22/56) of patients. Recurrent or persistent disease was identified in 82% (18/22) of cases with amplification and 50% (14/28) of nonamplified cases (P = .04). Mean time to recurrence was shorter in cases with amplification (6.2 months) than those without amplification (10.1 months) (P = .01). Eighteen patients (82%) with amplification and 10 patients (38%) without amplification died of disease or are alive with disease (P = .001). The mean follow-up period was 15.8 months for patients with amplification and 18.6 months for patients without amplification. Overall survival was significantly diminished in patients with amplification (P = .002). Amplification was not related to nodal status, distant metastases, or initial disease stage. CONCLUSIONS: Amplification of chromosome 11q13 loci may be an important biologic marker indicating poor prognosis, independent of clinical stage in head and neck squamous cell carcinoma, and it should be assessed in prospective trials to determine its utility for stratifying treatment and determining prognosis.


Assuntos
Carcinoma de Células Escamosas/genética , Cromossomos Humanos Par 11/genética , Amplificação de Genes , Neoplasias de Cabeça e Pescoço/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Estatísticas não Paramétricas , Análise de Sobrevida
13.
Ann Thorac Surg ; 58(6): 1762-4, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7979756

RESUMO

The use of indwelling central catheters for hyperalimentation, chemotherapy, and long-term venous access is increasing. We report the successful removal of an infected right atrial mass associated with the use of a central catheter in an adult with sickle cell disease. The clinical options for the treatment of infected atrial thrombus as well as the challenge of performing cardiopulmonary bypass in patients with sickle cell disease are briefly discussed.


Assuntos
Ponte Cardiopulmonar , Trombose Coronária/complicações , Trombose Coronária/cirurgia , Traço Falciforme/complicações , Infecções Estafilocócicas/complicações , Staphylococcus epidermidis , Adulto , Cateteres de Demora/efeitos adversos , Átrios do Coração , Humanos , Masculino , Traço Falciforme/etiologia , Infecções Estafilocócicas/etiologia
14.
Med Clin North Am ; 76(3): 745-55, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1578968

RESUMO

Erythropoiesis involves a cascade of differentiation steps that are driven by a variety of glycoproteins. The authors discuss erythropoietin, interleukin-3, and granulocyte macrophage colony-stimulating factor, the best understood of the growth factors regulating erythropoiesis, as well as tumor necrosis factor and other cytokines.


Assuntos
Eritropoese/fisiologia , Substâncias de Crescimento/fisiologia , Eritropoetina/fisiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/fisiologia , Humanos , Interleucina-3/fisiologia , Fator de Necrose Tumoral alfa/fisiologia
15.
Thorac Cardiovasc Surg ; 34(4): 217-22, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2429387

RESUMO

Median nerve somatosensory evoked potentials were recorded in 21 patients undergoing cardiac surgical procedures utilizing cardiopulmonary bypass, in order to establish the effects of hypothermia, reductions in mean arterial pressure, and alterations in cardiopulmonary bypass flows on evoked potential latency. Induction and maintenance of anesthesia with fentanyl caused a significant prolongation of latency of the first cortical peak. Temperature changes were linearly correlated with changes in latency for peaks recorded from Erb's point (r = -0.843, p less than 0.01) and the contralateral cortex (r = 0.843, p less than 0.01). There was no significant effect of mean arterial pressure or cardiopulmonary bypass flow reductions on latencies under the conditions of this study. Our results emphasize the importance of monitoring peripheral and first cortical peak latencies in evaluating somatosensory evoked potentials. It is suggested that peak latency prolongations beyond those predicted by temperature alterations may be indicative of hypoperfusion.


Assuntos
Pressão Sanguínea , Temperatura Corporal , Ponte Cardiopulmonar , Potenciais Somatossensoriais Evocados , Tempo de Reação/fisiologia , Adulto , Idoso , Anestesia Intravenosa , Pressão Sanguínea/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Ponte Cardiopulmonar/efeitos adversos , Eletrocardiografia , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Feminino , Fentanila , Humanos , Masculino , Nervo Mediano/fisiologia , Pessoa de Meia-Idade , Tempo de Reação/efeitos dos fármacos
16.
Astrophys J ; 289: 613-7, 1985 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11542019

RESUMO

We have carried out a search for the 234 GHz N = 2 --> 0, J = 1 --> 1 transition of 16O18O using the 13.7 m FCRAO radio telescope. No emission was detected toward six giant molecular clouds. Observations of the 220 GHz J = 2 --> 1 transition of C18O yield column densities for this species 1-3 x 10(16) cm-2; the resulting limits on the [O2]/[CO] ratio lie between <0.5 and <4. According to various chemical models, the ratio of molecular oxygen to carbon monoxide is primarily sensitive to the age of a cloud and to its carbon to oxygen ratio. For ages exceeding 3 x 10(6) yr and total carbon-to-oxygen ratio < 1, [O2]/[CO] can approach unity. Our best limits can be interpreted as indicating that the observed clouds are not chemically "mature" or that [carbon]/[oxygen] > 1. However, significant exploitation of molecular oxygen as a tracer of cloud structure and evolution will require more sensitive observations, which may be best carried out from above Earth's atmosphere.


Assuntos
Astronomia , Poeira Cósmica/análise , Meio Ambiente Extraterreno , Oxigênio/análise , Fenômenos Astronômicos , Monóxido de Carbono/análise , Modelos Químicos , Oxigênio/química , Análise Espectral
17.
Infect Immun ; 38(1): 292-7, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7141693

RESUMO

Clinicopathological correlations from human cases and experimental animal studies suggest that neutrophils are critical components of the host response to mucormycosis but that other cellular defense mechanisms appear to be important as well. Since our previous studies demonstrated that Rhizopus oryzae hyphae which are too large to be ingested completely can be damaged and probably killed by human neutrophils, we studied the antihyphal activity of human monocytes. As with neutrophils, light and electron microscopic studies indicated that monocytes attached to hyphae and appeared to destroy them in the absence of serum. As judged by our previously described assay for the leukocyte-induced inhibition of [14C]uracil uptake by hyphae, quantitative damage to hyphae by monocytes was 40.8 +/- 2.2% in 54 experiments. Neither attachment to nor damage of hyphae by monocytes was augmented by the presence of 10% human serum. As with neutrophils, monocyte-mediated damage of R. oryzae was significantly decreased by some inhibitors of oxidative metabolism and scavengers of the potentially microbicidal oxidative leukocyte products, which included 10(-4)M sodium azide, 10 (-3) M sodium cyanide, catalase, 10(-3) M histidine, 10(-3) M tryptophan, and 10(-4) M 1,4-diazobicyclo[2.2.2]octane but not superoxide dismutase, 1.4 X 10(-2) M dimethyl sulfoxide, and 4.0 X 10(-1) M mannitol. Moreover, monocytes from three patients with chronic granulomatous disease failed to damage hyphae at all. In contrast to our previous data for neutrophils, polyanions (10(-5) M polyaspartic or polyglutamic acid) did not inhibit monocyte-mediated hyphal damage. Thus, monocytes can damage and probably kill R. oryzae hyphae by oxidative mechanisms and so may be involved in host defense mechanisms against mucormycosis.


Assuntos
Monócitos/fisiologia , Rhizopus/fisiologia , Azidas/farmacologia , Catalase/farmacologia , Doença Granulomatosa Crônica/sangue , Histidina/farmacologia , Humanos , Técnicas In Vitro , Monócitos/microbiologia , Monócitos/ultraestrutura , Piperazinas/farmacologia , Rhizopus/ultraestrutura , Azida Sódica , Cianeto de Sódio/farmacologia , Triptofano/farmacologia
18.
Infect Immun ; 38(1): 380-2, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6754617

RESUMO

Chemotaxis of human neutrophils and monocytes was stimulated by sera activated with greater than or equal to 1.25 x 10(6) Cryptococcus neoformans. Leukocytes from five renal transplant recipients had depressed chemotactic responses to C. neoformans-activated sera when compared with normal subjects (P less than 0.05). Concentrations of cryptococcal capsular polysaccharide less than 1 mg/ml failed to generate chemotactic factors from sera.


Assuntos
Fatores Quimiotáticos/fisiologia , Quimiotaxia de Leucócito , Cryptococcus neoformans/fisiologia , Cryptococcus/fisiologia , Humanos , Hidrocortisona/farmacologia , Terapia de Imunossupressão , Transplante de Rim , Linfoma/sangue , Monócitos/fisiologia , Neutrófilos/fisiologia , Polissacarídeos Bacterianos/fisiologia
20.
Science ; 211(4482): 580-2, 1981 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-17840958

RESUMO

A submillimeter heterodyne radiometer, developed for astronomical applications, uses an optically pumped laser local oscillator and a quasi-optical Schottky diode mixer. The resultant telescope-mounted system, which has a noise temperature less than 4000 K (double sideband) and high frequency and spatial resolution, has been used to detect the J = 6 --> 5 rotational transition of carbon monoxide at 434 micrometers in the Orion molecular cloud. The measurements, when compared with previous millimeter-wave data, indicate that the broad carbon monoxide emission feature is produced by an optically thin gas whose temperature exceeds 180 K.

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