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1.
J Environ Manage ; 254: 109810, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31698300

RESUMEN

In order to predict the effects of climate change on the global carbon cycle, it is crucial to understand the environmental factors that affect soil carbon storage in grasslands. In the present study, we attempted to explain the relationships between the distribution of soil carbon storage with climate, soil types, soil properties and topographical factors across different types of grasslands with different grazing regimes. We measured soil organic carbon in 92 locations at different soil depth increments, from 0 to 100 cm in southwestern China. Among soil types, brown earth soils (Luvisols) had the highest carbon storage with 19.5 ±â€¯2.5 kg m-2, while chernozem soils had the lowest with 6.8 ±â€¯1.2 kg m-2. Mean annual temperature and precipitation, exerted a significant, but, contrasting effects on soil carbon storage. Soil carbon storage increased as mean annual temperature decreased and as mean annual precipitation increased. Across different grassland types, the mean carbon storage for the top 100 cm varied from 7.6 ±â€¯1.3 kg m-2 for temperate desert to 17.3 ±â€¯2.9 kg m-2 for alpine meadow. Grazing/cutting regimes significantly affected soil carbon storage with lowest value (7.9 ±â€¯1.5 kg m-2) recorded for cutting grass, while seasonal (11.4 ±â€¯1.3 kg m-2) and year-long (12.2 ±â€¯1.9 kg m-2) grazing increased carbon storage. The highest carbon storage was found in the completely ungrazed areas (16.7 ±â€¯2.9 kg m-2). Climatic factors, along with soil types and topographical factors, controlled soil carbon density along a soil depth in grasslands. Environmental factors alone explained about 60% of the total variation in soil carbon storage. The actual depth-wise distribution of soil carbon contents was significantly influenced by the grazing intensity and topographical factors. Overall, policy-makers should focus on reducing the grazing intensity and land conversion for the sustainable management of grasslands and C sequestration.


Asunto(s)
Carbono , Suelo , Ciclo del Carbono , China , Pradera , Poaceae
3.
Bioengineering (Basel) ; 10(1)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36671686

RESUMEN

Owing to the demand for the consumption of healthy extrudates, this study explored the infusion of neera (coconut inflorescence sap) honey in rice flour, corn flour and coconut milk residue blend-based extrudates. Neera honey, the concentrated coconut inflorescence sap, has numerous nutrients and a natural source of essential vitamins. Hence, the potential of neera honey as a biofortifying compound for the production of healthy extrudates was investigated. The rice and corn based extrudates supplemented with different concentration of neera honey have been prepared until the mix reaches 16 and 20% (w.b.) of feed moisture. Effect of addition of neera honey on the physical properties (expansion ratio, bulk density, specific length), functional properties (water absorption, water solubility, oil absorption), biochemical properties (total carbohydrates, total sugar, reducing sugar, phenolics, flavonoids, antioxidants), color parameters(L*, a*, b*), proximate compositions (moisture content, ash, protein, fat) and mineral profile of extrudates were recorded. Results suggest that addition of neera honey had a significant (p ˂ 0.05) impact on all the physico-chemical parameters evaluated. Incorporation of neera honey (feed moisture -20%) resulted in extrudates with less expansion, high bulk density and specific length, having high sugar, protein, phenolics, vitamin C and antioxidant activity. The combination of 60% rice flour + 25% corn flour +15% coconut milk residue samples infused with neera honey upto 16% feed moisture was found suitable for the preparation of nutritious extrudates based on functional characterization and minerals evaluation.

4.
J Texture Stud ; 53(6): 870-882, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35583967

RESUMEN

The impacts of cocoa solids and coconut sugar on the sensory perception of bean-to-bar dark chocolate were investigated with mixture design using response surface methodology. The maximum and minimum levels of cocoa nib, cocoa butter, and coconut sugar for the preparation of chocolate were 35-50%, 15-30%, and 20-35%, respectively. A suitable mathematical model was used to evaluate each response. Maximum and minimum levels of components caused a poor sensory acceptance of the resultant dark chocolate. The optimum level of independent variables, for the best set of responses, was 44.7% cocoa nib, 25.2% cocoa butter, and 30.2% coconut sugar, with a hedonic score of 8.28 for appearance, 8.64 for mouth feel, 8.71 for texture, 8.68 for taste, and 8.51 for overall acceptability, at a desirability of 0.86. The minimum time for grinding the chocolate mix was 24 hour, which was evident from the microscopic analysis of the chocolate mix. The optimized chocolate (70% dark) per 100 g constitutes 1.06 g moisture, 50.09 g crude fat, 10.37 g crude protein, 35.90 g carbohydrates, and 2.55 g ash content. The L, a, b values indicated a darker color and was stable under ambient condition with a hardness value of 59.52 N, which significantly decreased to 16.23 N within 10 min at ambient temperature (30 ± 2°C). The addition of coconut sugar along with cocoa solids incorporates polyphenols, flavonoids, antioxidant potential, and minerals into bean-to-bar dark chocolate and hence offers a commercial value and health potential for stakeholders.


Asunto(s)
Cocos , Azúcares
5.
Front Med (Lausanne) ; 8: 690594, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34485332

RESUMEN

Background: The failure of the embryonic hyaloid vascular system to regress naturally causes persistent hyperplastic primary vitreous (PHPV), a congenital eye disease. PHPVs molecular pathway, candidate genes, and drug targets are unknown. The current paper describes a comprehensive analysis using bioinformatics to identify the key genes and molecular pathways associated with PHPV, and to evaluate potential therapeutic agents for disease management. Methods: The genes associated with PHPV were identified using the pubmed2ensembl text mining platform. GeneCodis was employed to evaluate the Gene Ontology (GO) biological process terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Search Tool for the Retrieval of Interacting Genes (STRING) constructed a protein-protein interaction (PPI) network from the text mining genes (TMGs) in Cytoscape. The significant modules were clustered using Molecular Complex Detection (MCODE), and the GO and KEGG analysis for the hub genes were analyzed with the Database of Annotation, Visualization and Integrated Discovery (DAVID) tool. ClueGO, CluePedia, and ShinyGo were used to illustrate the functions and pathways of the clustered hub genes in a significant module. The Drug-Gene Interaction database (DGIdb) was used to evaluate drug-gene interactions of the hub genes to identify potential PHPV drug candidates. Results: A total of 50 genes associated with PHPV were identified. Overall, 35 enriched GO terms and 15 KEGG pathways were discovered by the gene functional enrichment analysis. Two gene modules were obtained from the PPI network constructed with 31 nodes with 42 edges using MCODE. We selected 14 hub genes as core candidate genes: TP53, VEGFA, SMAD2, CDKN2A, FOXC, FZD4, LRP5, KDR, FZD5, PAX6, MYCN, NDP, PITX2, and PAX2, primarily associated with camera-type eye morphogenesis, pancreatic cancer, the apoptotic process involved in morphogenesis, and the VEGF receptor signaling pathway. We discovered that 26 Food and Drug Administration (FDA)-approved drugs could target 7 of the 14 hub genes. Conclusions: In conclusion, the results revealed a total of 14 potential genes, 4 major pathways, 7 drug gene targets, and 26 candidate drugs that could provide the basis of novel targeted therapies for targeted treatment and management of PHPV.

6.
Int J Oral Maxillofac Surg ; 50(12): 1533-1539, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33714613

RESUMEN

The evaluation of speech outcomes after resection and reconstruction of the oral tongue remains largely unsystematic. A cross-sectional study was performed to analyse the speech outcomes of patients who underwent curative treatment with appropriate reconstruction. Sixty-nine patients were assessed for speech intelligibility and phonetics using a validated speech intelligibility assessment tool in the local language. Volume defects were classified as class I (less than one third), II (one third to half), III (half to two-thirds), or IV (two-thirds to total glossectomy). Defect location was defined as lateral, tip, or sulcus. The χ2 test and Kruskal-Wallis test were used to test volume and location as predictors. Twenty-six patients had class I defects, 29 had class II defects, seven had class III defects, and seven had class IV defects. Twenty-two patients (31.9%) received adjuvant radiotherapy. Mean vowel, consonant, word, and paragraph intelligibility were 99.27%, 86.86%, 85.52%, and 88.72%, respectively. The incremental volume of the glossectomy defect was significantly correlated with speech intelligibility scores and phonatory alterations. In classes II and III, tip resection significantly affected interdental sounds. All patients in class III had affected alveolar and alveo-palatal sounds. The results positively corroborated the volume and location of the glossectomy defect to a classification system.


Asunto(s)
Procedimientos de Cirugía Plástica , Neoplasias de la Lengua , Estudios Transversales , Glosectomía , Humanos , Inteligibilidad del Habla , Neoplasias de la Lengua/cirugía
7.
Br J Oral Maxillofac Surg ; 59(10): 1157-1165, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34281738

RESUMEN

Due to the risk of occult cervical metastasis, elective neck dissection (END) is recommended in the management of patients with early oral cavity squamous cell carcinoma (OSCC) and a clinically node-negative (cN0) neck. This paper presents a systematic review and meta-analysis of studies that recorded isolated regional recurrence (RR) in the pathologically node-negative neck dissection (pN0) neck following END in order to quantify the failure rate. Pubmed and Ovid databases were systematically searched for relevant articles published between January 2009 and January 2019. Studies reporting RR following END in patients with OSCC who had no pathological evidence of lymph node metastasis were eligible for inclusion in this meta-analysis. In addition, a selection of large head and neck units were invited to submit unpublished data. Search criteria produced a list of 5448 papers, of which 18 studies met the inclusion criteria. Three institutions contributed unpublished data. This included a total of 4824 patients with median follow-up of 34 months (2.8 years). Eight datasets included patients staged T1-T4 with RR 17.3% (469/2711), 13 datasets included patients staged T1-T2 with RR 7.5% (158/2113). Overall across all 21 studies, isolated neck recurrence was identified in 627 cases giving a RR of 13.0% (627/4824) on meta-analysis. Understanding the therapeutic effectiveness of END provides context for evaluation of clinical management of the cN0 in these patients. A pathologically negative neck does not guarantee against future recurrence.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Disección del Cuello , Estadificación de Neoplasias , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello
8.
Neurol India ; 68(6): 1418-1422, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33342879

RESUMEN

CONTEXT: Neurosurgical training in India. AIMS: To establish a sustainable, functional, and relatively inexpensive neurosurgical training system. METHODS AND MATERIALS: The training system involved using a relatively inexpensive stereoscopic microscope and ophthalmological microinstruments , including two jewellers' forceps and a microscissors. Training modules were designed using commonly available materials such as gauze, latex gloves, and chicken wings. STATISTICAL ANALYSIS USED: None. RESULTS: The system proved to be easy to construct, easy-to-use, and highly compact. This system allowed for residents to practice microsuturing and vessel anastomosis and allows the resident to be familiarized with operating under the microscope. Thereby , developing the hand-eye coordination and precise motor control required for neurosurgery as well as the art of appropriate tissue handling. CONCLUSIONS: The inexpensive nature of this training system and its inherent simplicity allows for a larger portion of neurosurgical residents in India, without access to sophisticated skills labs, to practice their skills in a controlled environment, without compromising on their ward duties.


Asunto(s)
Internado y Residencia , Neurocirugia , Animales , Competencia Clínica , India , Neurocirugia/educación , Procedimientos Neuroquirúrgicos
9.
J Laryngol Otol ; 134(4): 350-353, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32172698

RESUMEN

OBJECTIVES: Pharyngocutaneous fistulae are dreaded complications following total laryngectomy. This paper presents our experience using 3-5 ml gastrografin to detect pharyngeal leaks following total laryngectomy, and compares post-operative videofluoroscopy with clinical follow-up findings in the detection of pharyngocutaneous fistulae. METHODS: A retrospective case-control study was conducted of total laryngectomy patients. The control group (n = 85) was assessed clinically for development of pharyngocutaneous fistulae, while the study group (n = 52) underwent small-volume (3-5 ml) post-operative gastrografin videofluoroscopy. RESULTS: In the control group, 24 of 85 patients (28 per cent) developed pharyngocutaneous fistulae, with 6 requiring surgical correction. In the study group, 24 of 52 patients (46 per cent) had videofluoroscopy-detected pharyngeal leaks; 4 patients (8 per cent) developed pharyngocutaneous fistulae, but all cases resolved following non-surgical management. Patients who underwent videofluoroscopy had a significantly lower risk of developing pharyngocutaneous fistulae; sensitivity and specificity in the detection of pharyngocutaneous fistulae were 58 per cent and 100 per cent respectively. CONCLUSION: Small-volume gastrografin videofluoroscopy reliably identified small pharyngeal leaks. Routine use in total laryngectomy combined with withholding feeds in cases of early leaks may prevent the development of pharyngocutaneous fistulae.


Asunto(s)
Fístula Cutánea/diagnóstico por imagen , Diatrizoato de Meglumina/administración & dosificación , Fluoroscopía/métodos , Laringectomía/efectos adversos , Enfermedades Faríngeas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Fístula Cutánea/prevención & control , Fístula Cutánea/terapia , Femenino , Fluoroscopía/tendencias , Humanos , Masculino , Tamizaje Masivo/instrumentación , Persona de Mediana Edad , Faringe/diagnóstico por imagen , Faringe/patología , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Sensibilidad y Especificidad
10.
Science ; 223(4638): 828-30, 1984 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-6695185

RESUMEN

Noninvasive photoacoustic spectroscopy was used to study the malaria parasites Plasmodium chabaudi and Plasmodium berghei, their pigment, and ferriprotoporphyrin IX, which is a by-product of the hemoglobin that the parasite ingests. The results indicate that the pigment consists of ferriprotophorphyrin self-aggregates and a noncovalent complex of ferriprotoporphyrin and protein. Spectra of chloroquine-treated parasites reveal in situ interaction between the drug and ferriprotoporphyrin. Chloroquine-resistant parasites, readily distinguishable by this method, appear to degrade hemoglobin only partially.


Asunto(s)
Eritrocitos/parasitología , Plasmodium/fisiología , Análisis Espectral/métodos , Animales , Cloroquina/farmacología , Resistencia a Medicamentos , Hemoproteínas/metabolismo , Hemina/metabolismo , Hemoglobinas/metabolismo , Ratones , Protoporfirinas/metabolismo
11.
Int J Oral Maxillofac Surg ; 48(2): 152-156, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30243830

RESUMEN

According to the eighth edition of the AJCC Cancer Staging Manual (AJCC8), a depth of invasion (DOI) >10mm is classified as pT3, representing a locally advanced tumour requiring postoperative radiotherapy (PORT). When node-negative, however, evidence regarding whether PORT improves loco-regional control or survival is unclear. To clarify this, two cohorts of patients were studied: (1) patients classified as pT3N0 by the seventh edition of the AJCC manual (AJCC7), with DOI >10mm and a tumour diameter >4cm (17 patients who received PORT), and (2) patients classified as pT1N0 and pT2N0 by AJCC7, with DOI >10mm and a tumour diameter <4cm (55 patients who did not receive PORT). Loco-regional control and survival were analysed. PORT was found not to impact overall survival or disease-free survival. It was also found not to impact local, regional, or distant recurrence. Although the two subsets of patients considered here (DOI >10mm with tumour diameter below or above 4cm) were previously distinct, they are both considered pT3 in AJCC8. Data from this study indicate that the routine administration of PORT to patients with a DOI >10mm may not be warranted in the absence of other risk features such as nodal disease or close margins.


Asunto(s)
Neoplasias de la Boca/patología , Neoplasias de la Boca/radioterapia , Adulto , Anciano , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/diagnóstico por imagen , Neoplasias de la Boca/cirugía , Clasificación del Tumor , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Estudios Prospectivos , Dosificación Radioterapéutica , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Tasa de Supervivencia , Resultado del Tratamiento
12.
Int J Oral Maxillofac Surg ; 47(12): 1507-1510, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30401471

RESUMEN

Traditional neck dissection for oral squamous cell carcinoma (OSCC) involves removal of the submandibular salivary gland. Several studies have cited the low incidence of direct gland invasion by tumours and have recommended gland-sparing neck dissection. In this study, a detailed audit of level Ib involvement in OSCC was performed in order to assess the feasibility of submandibular gland-sparing in neck dissection; the rate of direct involvement by the primary tumours, the involvement of periglandular level Ib nodes, and their determinants were investigated. A total of 586 neck dissection specimens obtained between 2005 and 2014 from patients operated on at the study institution for floor of mouth, tongue, and buccal primaries, were evaluated for direct invasion of the gland and periglandular lymphadenopathy. Of 226 node-positive patients, 21 (9.3%) had direct gland invasion by tumour. Risk factors were tumour diameter >4cm (P=0.002) and depth of invasion >10mm (P=0.003). Determinants of periglandular lymphadenopathy were depth of invasion >10mm (P<0.001), perineural invasion (P=0.02), lymphovascular invasion (P=0.014), and moderate/poor differentiation (P<0.0001). Gland-sparing neck dissection is safe in early tumours (pT1pN0-1), with a good chance of minimizing xerostomia without radiotherapy. Larger tumours without clear evidence of submandibular gland invasion or suspicious level Ib lymphadenopathy may be considered for gland preservation, however the oncological safety is unclear.


Asunto(s)
Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Neoplasias de la Boca/patología , Neoplasias de la Boca/cirugía , Disección del Cuello/métodos , Glándula Submandibular/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
13.
Lymphology ; 51(3): 109-118, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30422433

RESUMEN

Secondary head and neck lymphedema (SHNL) is a chronic condition affecting patients who have undergone treatment for head and neck cancers. It results from the disruption of normal lymphatic flow by surgery and/or radiation. The incidence of secondary head and neck lymphedema varies anywhere between 12 and 54% of all patients treated for head and neck cancer, but it is still commonly under-diagnosed in routine clinical practice. In spite of awareness of this condition, treatment has been difficult as definitive staging, diagnostic, and assessment tools are still under development. This review article is aimed at looking at the evidence, standards of management, and deficiencies in current literature related to SHNL to optimize management of these patients and improve their quality of life.


Asunto(s)
Terapia Combinada/efectos adversos , Neoplasias de Cabeza y Cuello/terapia , Linfedema/etiología , Humanos , Linfedema/patología , Pronóstico
14.
J Laryngol Otol ; 132(8): 742-747, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30073942

RESUMEN

OBJECTIVE: Elderly patients have been consistently shown to receive suboptimal therapy for cancers of the head and neck. This study was performed to determine the peri-operative outcomes of these patients and compare them with those of younger patients. METHODS: In this retrospective analysis, 115 patients aged 70 years or more undergoing major surgery for head and neck cancers were matched with 115 patients aged 50-60 years, and univariate analysis was performed. RESULTS: Elderly patients had a reduced performance status (p < 0.001) and more co-morbid illnesses (p = 0.007), but a comparable intra-operative course. They had a longer median hospital stay (p = 0.016), longer intensive care unit stay (p = 0.04), longer median tracheostomy dependence (p = 0.04) and were more often discharged with feeding tubes (p < 0.001). They also had a higher incidence of post-operative non-fatal cardiac events (p = 0.045). CONCLUSION: Elderly patients with good performance status should receive curative-intent surgery. Although hospital stay and tube dependence are longer, morbidity and mortality are comparable with younger patients.


Asunto(s)
Carcinoma/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Complicaciones Posoperatorias/epidemiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Carcinoma/mortalidad , Carcinoma/patología , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Estado de Salud , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
15.
Indian J Tuberc ; 65(4): 280-284, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30522613

RESUMEN

BACKGROUND: Tuberculosis (TB) is one of world's oldest infectious disease and ranks alongside HIV as leading infectious killer. Tuberculosis infection control especially in HIV and TB care facilities has warranted attention after the recent health care-associated outbreaks in South Africa. The aim of this study was to describe the tuberculosis infection control measures implemented by HIV and TB care facilities in five high HIV burden provinces in India. METHODS: Baseline assessment of 30 high burden Antiretroviral centers and TB facilities was conducted during Oct 2015-Dec 2015 by AIC trained staff using a structured format. RESULTS: Thirty HIV and TB care facilities in five high HIV burden provinces were enrolled. Facility infrastructure and airborne infection control practices were highly varied between facilities. TB screening and fast tracking at ART centers is happening at majority of centers however inadequate TB infection control training, poor compliance to administrative and personal protective measures and lack of mechanism for health care workers surveillance need attention. CONCLUSIONS: Local specific TB infection control interventions to be designed and implemented at HIV and TB care facilities including implementation of administrative, environmental and use of personal protective equipment's with the training of staff members. Health care workers surveillance needs to be prioritized considering the rising instances of tuberculosis among Health care workers.


Asunto(s)
Infección Hospitalaria/epidemiología , Brotes de Enfermedades , Infecciones por VIH/epidemiología , Control de Infecciones , Tuberculosis Pulmonar/epidemiología , Infección Hospitalaria/complicaciones , Infección Hospitalaria/prevención & control , Infecciones por VIH/complicaciones , Infecciones por VIH/prevención & control , Instituciones de Salud , Humanos , India/epidemiología , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/prevención & control
16.
Surg Neurol Int ; 8: 126, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28713630

RESUMEN

BACKGROUND: Tuberculosis is a very common disease in India. Its prevalence, capacity to affect every other organ, and atypical presentations make it an important part of the differential diagnosis for cases presenting in the rural setup. Primary tuberculous caries of the calvarium is a rare manifestation of this common entity. CASE DESCRIPTION: A young lady presented with headache and discharging sinus of the scalp. Imaging revealed epidural abscess with midline shift. She underwent surgery, and histopathological diagnosis of tuberculous etiology was made. The pre and intraoperative images, radiological images, and histopathological images are reported and discussed. CONCLUSION: Tuberculosis should be included in the differential diagnosis of the osteolytic lesions of skull with discharging sinus. A high degree of suspicion, especially in patients from low socioeconomic status, is warranted in managing such cases.

17.
Indian J Cancer ; 54(1): 2-5, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29199651

RESUMEN

Metastatic head and neck squamous cell carcinoma (HNSCC) has traditionally carried a dismal prognosis; however with advances in care, it has been shown that pulmonary metastasectomy is a viable therapeutic option in selected patients, palliating symptoms and improving survival. With the increasing incidence of human papilloma virus-related HNSCC and better availability of minimal access surgery, there is a need to better understand the role of pulmonary metastasectomy in the treatment of HNSCC. This article summarizes the literature on indications, results, surgical options and approaches, clinical dilemmas, and controversies associated with pulmonary metastasectomy in HNSCC, to identify suitable candidates and optimize outcomes.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Metastasectomía/métodos , Neumonectomía , Pronóstico , Carcinoma de Células Escamosas de Cabeza y Cuello
18.
Biochim Biophys Acta ; 1294(1): 8-14, 1996 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-8639718

RESUMEN

We have monitored the molecular conformation, stability, interaction and dynamics of keratan sulfate proteoglycan, the major structural protein component of the cornea, in solution, by studying the fluorescence spectral features of its tryptophan residues as component-specific intrinsic spectral probes (collagen, the other structural component of the cornea, has no tryptophans). Our study suggests that the Trp region of the molecule is in a motionally restricted environment as it exhibits a fluorescence red-edge effect and shows dipole relaxation. The extrinsic spectral probe 8-anilinonaphthalene 1-sulfonate reveals keratan sulfate proteoglycan to possess significant surface hydrophobicity. This dual character of keratan sulfate proteoglycan allows us to label it as an 'ambidextran' proteoglycan. The molecule is stable between pH 5-8 and has a Tm value of 72 degrees C. Disulfide bonds play a role in the stability of the molecule. KSPG is seen to interact with collagen and the model compound, poly(L-proline). Interaction of the proteoglycan with unilamellar vesicles appears to be more interfacial than penetrative. This dual interaction displayed by KSPG with collagen and with lipid assemblages suggests that it plays the role of a 'filler' in the extracellular matrix of the cornea.


Asunto(s)
Proteoglicanos Tipo Condroitín Sulfato/química , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Córnea/química , Sulfato de Queratano/química , Sulfato de Queratano/metabolismo , Animales , Bovinos , Cesio/metabolismo , Dicroismo Circular , Colágeno/metabolismo , Guanidina , Guanidinas/farmacología , Concentración de Iones de Hidrógeno , Liposomas , Lumican , Fosfatidilcolinas/metabolismo , Conformación Proteica , Espectrometría de Fluorescencia , Temperatura , Triptófano/metabolismo
19.
Biochim Biophys Acta ; 1065(1): 35-41, 1991 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-1710497

RESUMEN

Polysaccharide chains are usually considered to be highly hydrophilic, since they have no obvious nonpolar moieties in them. Yet, it is possible to realise conformations in these chains wherein all the hydroxy groups are disposed in one side or face of the chain and the hydrogens disposed in the other. We experimentally demonstrate that such an amphiphilic surface is present in linear oligomeric dextrins, i.e., alpha-1,4-linked D-glucosides, but not in alpha-1,6-D-glucosides (dextrans) or in beta-1,4-D-glucosides (cellulose). This amphiphilicity is generated as a consequence of the stereochemical constraints, which vary with the structure of the sugar and with the type of linkage. Oligosaccharide chains that can adopt incipient helical structures might display amphiphilicity. This property might be relevant to intermolecular recognition on cell surfaces, lectin-sugar binding, antigen-antibody interactions and the like, and might be manifested more in heteromolecular recognition process than as homomolecular self-aggregation.


Asunto(s)
Dextranos/química , Oligosacáridos/química , Conformación de Carbohidratos , Cetrimonio , Compuestos de Cetrimonio , Detergentes , Transferencia de Energía , Colorantes Fluorescentes , Glucosa/química , Modelos Moleculares , Relación Estructura-Actividad , Propiedades de Superficie , Termodinámica , Xilanos/química
20.
Photochem Photobiol ; 81(3): 498-501, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15623354

RESUMEN

Cataract of the eye lens is characterized by (1) progressive opacification or loss of transparency; (2) accumulation of molecules that absorb in the UV-visible range of the spectrum; and (3) formation of fluid-filled vacuoles, particularly in diabetics when sugar levels in the lens are high. Of the various causative factors for cataract, light is an important one. Because the level of light below 320 nm reaching the lens is quite low, photodynamic effects of endogenous compounds absorbing in the UV-A-visible region become important in this connection. In this update we summarize a list of accumulant chromophores that have been identified in aging and cataract human lenses and their roles as potential sensitizers, antioxidants or as benign filters. Because such photodynamic cataractogenesis is oxidative in nature, we also cite examples where administration of antioxidants could help delay cataract progression.


Asunto(s)
Antioxidantes/farmacología , Catarata/metabolismo , Cristalino/efectos de los fármacos , Fármacos Fotosensibilizantes/farmacología , Protección Radiológica , Envejecimiento/metabolismo , Antioxidantes/uso terapéutico , Catarata/etiología , Catarata/prevención & control , Filtración , Humanos , Cristalino/metabolismo , Rayos Ultravioleta/efectos adversos
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