Mechanism of UV-related carcinogenesis and its contribution to nevi/melanoma

Melanoma consists 4-5 % of all skin cancers, but it contributes to 71-80 % of skin cancers deaths. UV light affects cell and tissue homeostasis due to its damaging effects on DNA integrity and modification of expression of a plethora of genes. DNA repair systems protect cells from UV-induced lesions. Several animal models of melanoma have been developed (Xiphophorus, Opossum Monodelphis domestica, mouse models and human skin engrafts into other animals). This review discusses possible links between UV and genes significantly related to melanoma but does not discuss melanoma genetics. These include oncogenes, tumor suppressor genes, genes related to melanocyte-keratinocyte and melanocyte-matrix interaction, growth factors and their receptors, CRH, ACTH, α-MSH, glucocorticoids, ID1, NF-kappaB and vitamin D3.     

A midface swelling in a child – A possible diagnostic dilemma

A lump on the midface of a child can pose as a diagnostic dilemma. There is a wide variety of possible differential diagnoses, ranging from simple benign conditions such as a sebaceous cyst, dermoid cyst, lipoma, neuroma and neurofibroma, to potentially devastating conditions such as odontogenic myxoma.A case of a child in which the formulation of a definite diagnosis was clinically and histologically challenging is presented.     

Comparison of pressure ulcer treatments in long-term care facilities: clinical outcomes and impact on cost.

This study compared clinical outcomes and nursing labor costs associated with (a) balsam Peru, hydrogenated castor oil, and trypsin (BCT) ointment; (b) BCT + Other; and (c) Other treatments in 2014 wound episodes occurring in 861 patients (mean 2.34 wounds/patient). Treatment with BCT ointment or BCT + Other was associated with a higher healing rate (P < .05). No Stage 1 or 2 ulcer treated with BCT ointment progressed, compared with 13.8% treated with BCT + Other and 13.4% treated with Other. The reported mean duration of treatment and time to heal were shorter for ulcers treated with BCT ointment, but differences did not reach significance, possibly because of the variability in reported treatment times. Mean daily nursing labor costs were lower for treatment with BCT than Other ($50.8 vs $61.7, P < .05). These data suggest that treatment of Stage 1 or 2 ulcers with BCT may be associated with shorter treatment time and time to heal and a potential reduction in treatment-related nursing labor costs.     

Left ventricular fibroma: echocardiographic diagnosis and successful surgical excision in three cases

The management of three patients with left ventricular fibromas is outlined. All were asymptomatic children. Routine chest radiography suggested cardiac masses. M-mode and two-dimensional echocardiography were valuable adjuncts to conventional angiography in assessing these children. Electrocardiographic changes, present in all cases, were shown to regress postoperatively. We stress the importance of these noninvasive aids in the initial investigation and outline our operative methods of reconstruction.     

New approaches to QSAR: Neural networks and machine learning

Summary Neural networks and machine learning are two methods that are increasingly being used to model QSARs. They make few statistical assumptions and are nonlinear and nonparametric. We describe back-propagation from the field of neural networks, and GOLEM from machine learning, and illustrate their learning mechanisms using a simple expository problem. Back-propagation and GOLEM are then compared with multiple linear regression (using the parameters and their squares) on two real drug design problems: the inhibition ofEscherichia coli dihydrofolate reductase (DHFR) by pyrimidines and the inhibition of rat/mouse tumour DHFR by triazines.     

Effect of hepatic artery chemotherapy on survival of patients with hepatic metastases from colorectal carcinoma treated with cryotherapy

Thirty-eight patients with unresectable multiple liver metastases from colorectal carcinoma were treated with either hepatic artery chemotherapy (HAC) and cryotherapy (n=27) or cryotherapy alone (n=11). Follow-up survival data were summarized using Cox regression. Allowing for the effect of the pathology of the primary tumor and the preoperative carcinoembryonic antigen (CEA) level, those patients who did not receive HAC after cytoreduction were three times as likely to die as those given HAC (RR 3.3, 95%; CI 1.2–9.3). The estimated median survival of patients treated with cryotherapy alone was 245 days, whereas for those given more than 3 months of HAC plus cytoreduction therapy it was 570 days. It is recommended that all patients who receive cryotherapy for multiple liver metastases from colorectal rectal carcinoma be given subsequent hepatic artery chemotherapy.

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Resumen En el presente estudio, 38 pacientes con metástasis hepáticas múltiples y no resecables de carcinoma colo-rectal fueron tratados con quimioterapia administrada en la arteria hepática (HAC) y crioterapia (n=27) o crioterapia sola (n=11). Los datos del seguimiento fueron resumidos según el método de regresión de Cox. Teniendo en cuenta el efecto de la patología del tumor primario y el nivel preoperatorio de antígeno carcino-embrionario, se halló que aquellos pacientes que no recibieron HAC luego de la citorreducción tuvieron una probabilidad de muerte 3 veces mayor que los que recibieron HAC (RR 3.3, 95% CI 1.2 a 9.3). La sobrevida media estimada de los pacientes tratados con crioterapia sola fue de 245 días, en tanto que aquellos que recibieron HAC por tres meses y terapia de citorreducción fue de 570 días. Se recomienda que todos los pacientes que reciben crioterapia para metástasis hepáticas múltiples de carcinoma colo-rectal reciban luego quimioterapia por vía de la arteria hepática.

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Résumé Trente-huit patients ayant des métastases hépatiques multiples non reséquables d'origine colorectale ont été traités soit par chimiothérapie par voie artérielle (CVA) associée à la cryothérapie (n=27) soit par cryothérapie seule (n=11). Les survies ont été analysées selon la méthode d'analyse du Modèle de Cox. En tenant compte de l'effet de la pathologie de la tumeur primitive et du niveau préopératoire de l'ACE, les patients n'ayant pas eu de de décéder que ceux qui en ont eu (RR 3.3, 95% IC 12 à 9.3). L'estimation de la survie médiane des patients traités par la cytoréduction seule a été de 245 jours, alors que celle des patients traités par les deux avec une CVA d'au moins trois mois, a été de 570 jours. On recommande que tous les patients ayant des métastases multiples du foie à partir des cancers colorectaux aient une CVA par la suite.