Central transcriptional regulator controls photosynthetic growth and carbon storage in response to high light.

Carbon capture and biochemical storage are some of the primary drivers of photosynthetic yield and productivity. To elucidate the mechanisms governing carbon allocation, we designed a photosynthetic light response test system for genetic and metabolic carbon assimilation tracking, using microalgae as simplified plant models. The systems biology mapping of high light-responsive photophysiology and carbon utilization dynamics between two variants of the same Picochlorum celeri species, TG1 and TG2 elucidated metabolic bottlenecks and transport rates of intermediates using instationary 13C-fluxomics. Simultaneous global gene expression dynamics showed 73% of the annotated genes responding within one hour, elucidating a singular, diel-responsive transcription factor, closely related to the CCA1/LHY clock genes in plants, with significantly altered expression in TG2. Transgenic P. celeri TG1 cells expressing the TG2 CCA1/LHY gene, showed 15% increase in growth rates and 25% increase in storage carbohydrate content, supporting a coordinating regulatory function for a single transcription factor.

Variation of δ18O in otoliths of Stellifer lanceolatus and Eucinostomus gula environmental change indicator in Terminos Lagoon, Mexico.

Environmental changes have been associated with natural climatic variability or human activity. Water resources management is, perhaps, the most drastic change observed in the coastal environment. However, external forcings such as the El Niño event have important implications in the global and regional hydrological balance. These environmental changes have an impact on the density and biomass of the ichthyofauna in the Terminos Lagoon (TL) for the past 30 years, presumably, associated with variations in the temperature and surface salinity of the sea. Therefore, in the present study, δ18O was quantified in otoliths of two important species due to their dominance: Stellifer lanceolatus and Eucinostomus gula, and to understand the environmental changes reflected in both species. The δ18O was analyzed in otoliths of these two species captured in 1998/1997, 2006/2007 and 2016/2017 and were compared with in situ temperature and salinity data. Sea surface temperature and salinity increased by 2 °C and 9, respectively, between 1997 and 2017. Stellifer lanceolatus δ18O values was in isotopic equilibrium with seawater calcite; while, E. gula is not in isotopic equilibrium. The δ18O of S. lanceolatus and E. gula varied significantly with the increase in salinity (R2 = 0.8987 and R2 = -0.2964) and not with the sea surface temperature. S. lanceolatus is an excellent bioindicator of changes in sea surface salinity in this region of the Gulf of Mexico.

Resonancia magnética funcional de reposo en el trastorno por déficit de atención e hiperactividad / Resting state functional magnetic resonance imaging in attention deficit hyperactivity disorder

OBJETIVOS: Explorar si los niños y adolescentes con trastorno por déficit de atención e hiperactividad (TDAH) tienen alterada la conectividad funcional entre la red de control ejecutivo y la red neuronal por defecto. MATERIAL Y MÉTODOS: Estudio exploratorio de prueba diagnóstica, prospectivo, con diseño de casos y controles. Se reclutaron consecutivamente 56 participantes (29 con TDAH de tipo inatento o combinado y 27 controles) entre 7 y 16 años, de sexo masculino, dominancia derecha. Se aplicaron los criterios diagnósticos del DSM-5 como prueba de referencia y una batería de pruebas neuropsicológicas para confirmar el diagnóstico y evaluar comorbilidades. Se les realizó resonancia magnética funcional de reposo como prueba índice. La aplicación y evaluación de las pruebas fue ciega. Las regiones cerebrales se escogieron a priori y se usó técnica de región de interés. Se evaluó la conectividad funcional de la corteza del cíngulo anterior (CCA) con el precuneus (P), la corteza del cíngulo posterior (CCP) y la corteza prefrontal dorsomedial (CPDM). RESULTADOS: Las conectividades funcionales en cada una de las asociaciones evaluadas en los pacientes con TDAH comparado con los controles fueron: P_D=0,41 vs. 0,44; CCP_D=0,43 vs. 0,53; CPDM_D=0,75 vs. 0,79; P_I=0,40 vs. 0,41; CCP_I=0,48 vs. 0,53; CPDM_I=0,76 vs. 0,72). D: lado derecho I: lado izquierdo. Valor de p> 0,05. CONCLUSIÓN: La conectividad funcional cerebral en estado de reposo es menor en los pacientes con TDAH cuando se compara con controles sanos; sin embargo, la diferencia no fue estadísticamente significativa

OBJECTIVE: To explore whether children and adolescents with attention deficit/hyperactivity disorder (ADHD) have altered the functional connectivity between the executive control network and the default mode network. METHODS: Exploratory study of a diagnostic test, prospective, case and control design. A total of 56 participants were recruited consecutively (29 inattentive or combined ADHD subtype and 27 controls) between 7 and 16 years old, male, right dominance. DSM-5 was applied as reference test and a battery of neuropsychological tests to confirm the diagnosis and assess comorbidities. Resting state functional magnetic resonance imaging was performed as an index test. The application and evaluation of the tests was blind. The brain regions were chosen a priori and the region of interest technique was used. The functional connectivity of the anterior cingulate cortex (ACC) was evaluated with: the precuneus (P), the posterior cingulate cortex (PCC) and the dorsomedial prefrontal cortex (DMPC). RESULTS: The functional connectivity in each of the associations evaluated in the patients with ADHD compared with the controls were: P_D=0.41 vs 0.44; CCP_D=0.43 vs 0.53; CPDM_D=0.75 vs. 0.79; P_I=0.40 vs 0.41; CCP_I=0.48 vs 0.53; CPDM_I=0.76 vs. 0.72). D: right side I: left side. Value of p> 0.05. CONCLUSION: Cerebral functional connectivity at rest is lower in ADHD patients when compared with healthy controls, however, the difference was not statistically significant

Resting state functional magnetic resonance imaging in attention deficit hyperactivity disorder. / Resonancia magnética funcional de reposo en el trastorno por déficit de atención e hiperactividad.

OBJECTIVE: To explore whether children and adolescents with attention deficit/hyperactivity disorder (ADHD) have altered the functional connectivity between the executive control network and the default mode network. METHODS: Exploratory study of a diagnostic test, prospective, case and control design. A total of 56 participants were recruited consecutively (29 inattentive or combined ADHD subtype and 27 controls) between 7 and 16 years old, male, right dominance. DSM-5 was applied as reference test and a battery of neuropsychological tests to confirm the diagnosis and assess comorbidities. Resting state functional magnetic resonance imaging was performed as an index test. The application and evaluation of the tests was blind. The brain regions were chosen a priori and the region of interest technique was used. The functional connectivity of the anterior cingulate cortex (ACC) was evaluated with: the precuneus (P), the posterior cingulate cortex (PCC) and the dorsomedial prefrontal cortex (DMPC). RESULTS: The functional connectivity in each of the associations evaluated in the patients with ADHD compared with the controls were: P_D=0.41 vs 0.44; CCP_D=0.43 vs 0.53; CPDM_D=0.75 vs. 0.79; P_I=0.40 vs 0.41; CCP_I=0.48 vs 0.53; CPDM_I=0.76 vs. 0.72). D: right side I: left side. Value of p> 0.05. CONCLUSION: Cerebral functional connectivity at rest is lower in ADHD patients when compared with healthy controls, however, the difference was not statistically significant.

[Injury of the anterior branch of the posterior interosseous nerve]. / Lesión de la rama anterior del nervio interóseo posterior.

INTRODUCTION: Posterior interosseous nerve syndrome, a branch of the radial nerve at the level of the forearm, is characterized by the motor function loss of some or all of the muscles innervated distally. CLINICAL CASE: A 26-year-old male with a history of proximal radius fracture associated to radial nerve injury, treated with osteosynthesis 7 years earlier, with full recovery, who currently presented intense pain 4 cm distal to the radial head, accompanied by paralysis of Extensor pollicis longus, Extesnor pollicis brevis and Abductor pollicis longus, with paresis of the Extensor indicis propius, in which a diagnosis of entrapment syndrome of the anterior descending branch of the posterior interosseous nerve (SNIP) was performed. DISCUSSION: The conservative management of SNIP is indicated during the first 8-12 weeks, if no improvement is found, the indication for surgical exploration is indicated, and the removal of osteosynthesis material is controversial.

INTRODUCCIÓN: El síndrome del nervio interóseo posterior, rama del nervio radial a nivel del antebrazo se caracteriza por la pérdida de función motora de algunos o todos los músculos inervados distalmente. CASO CLÍNICO: Masculino de 26 años con antecedente de fractura de radio proximal manejado con osteosíntesis que cursó con lesión del nervio radial siete años antes con recuperación completa, acude con dolor intenso a 4 cm distal a cabeza radial, acompañado de parálisis del extensor largo y corto del pulgar y del abductor del pulgar, con paresia del extensor propio del índice, en el que se efectúa diagnóstico de síndrome de atrapamiento de la rama anterior descendente del nervio interóseo posterior (SNIP). DISCUSIÓN: El manejo conservador del SNIP está indicado durante las primeras ocho a 12 semanas, de no mostrar mejoría la indicación de exploración quirúrgica está indicada, siendo el retiro de material de osteosíntesis controvertido.

Automated method for the determination of the band gap energy of pure and mixed powder samples using diffuse reflectance spectroscopy.

An automated method to determine the band gap energy (E g ) of pure and mixed powder compounds using diffuse reflectance spectroscopy is presented. This method is based on a five-step algorithm that mimics the judgment made by an expert analyst in identifying the linear segments in Tauc plots and subsequent estimation of the E g value. It is demonstrated that the method to estimate E g by intersecting the straight-line fit of the Tauc segment with the photon energy axis is not appropriate for those samples containing more than one optical absorbing phase because systematic underestimation of the E g value results. The automated method accounts for such cases by introducing a base line function. The robustness of the implemented algorithm was tested using three model systems, ZnO-Al2O3, ZnO-CoO and ZnO-CdO. The estimated E g 's using the automated method differ in less than 1% than those obtained by its manual counterpart.

Dam implications on salt-water intrusion and land use within a tropical estuarine environment of the Gulf of Mexico.

Estuaries are highly productive ecosystems, defined by salt-freshwater exchanges that are significantly altered by changes upstream and in adjacent coastal areas. Tropical estuaries are characterized by the periodic advance and retreat of saline intrusion, depending on seasonality, episodic river flows and flooding events. Salt-water intrusion due to the estuarine dynamics might be affected by dam systems, which could modify the hydrological regime of the estuary in relation to other stressors, such as land use changes. For this purpose, field measurements of salinity, temperature, river-discharge and flow velocities were conducted over a year to analyze the current hydrological regime in the upper estuary of the Grijalva River in the southern Gulf of Mexico, part of the Biosphere Reserve "Pantanos de Centla", one of the most biodiverse areas in the world. Analysis of land use and vegetation cover was performed. Historical implications of the hydrological performance of the four-dam system (1957 to 2014) are presented, together with the upstream-induced changes (i.e. discharge and seasonal water volumes variations): before, between and after the full operation of the dam system. A general loss of seasonality in the river discharge was identified (1974-1987), when critical mean annual water discharges were registered (Qmean from 263.56 to 126.49 m3/s). Chronological changes in the estuary and in the surrounding area due to the introduction of large extensions of cultivated grassland (~1020 km2), reduction in mangrove cover (~223 km2) and tular (~1340 km2) were noticed. These modifications mostly occurred before conservation strategies were implemented, such as the designation of the Biosphere Reserve (1992). This study contributes to a better understanding of the response of estuarine systems to anthropic perturbations and the development of long-term management plans that could take into account climate change and the increase of hydropower development.

[Parathyroid carcinoma: diagnosis by a femur fracture]. / Carcinoma de paratiroides: diagnóstico por fractura de fémur.

BACKGROUND: Carcinoma of the parathyroid gland (PC) described by De Quervain since 1909, it represents the least common neoplasm, with an incidence of 1,25/10,000,000 peoples. It has been reported approximately 1,000 cases of CP in world literature. There are two series in Mexico, one of eight patients and other with four cases. Because CP is functionally active, its early clinical behavior is similar to that of parathyroid benign neoplasms. CLINICAL CASE: A 66-year-old female with history of thighbone pain and spontaneous femoral fracture, osteolytic lesions, hypercalcemia, elevated levels of alkaline phosphatase and parathyroid hormone detected; the scintigraphy showed a functioning tumor located in upper mediastinum. By hemithyroidectomy in block, the tumor was resected. Histopathological study reported parathyroid carcinoma. DISCUSSION: PC is the least common neoplasia, in patients with parathyroid hormone levels greater than 1,000 pg/ml and hypercalcemia upper of 14 mg/dl this disease should be suspected.

ANTECEDENTES: El carcinoma de las glándulas paratiroides (CP) descrito por De Quervain en 1909 representa la neoplasia menos frecuente, siendo su incidencia de 1.25/10,000,000 personas. Se han reportado aproximadamente 1,000 casos de carcinoma paratiroideo en la literatura mundial. En México existen dos series, una de ocho pacientes y otra de cuatro, además de tres reportes de casos aislados. Dado que el CP es funcionalmente activo el comportamiento clínico inicial es similar a las neoplasias paratiroideas benignas. CASO CLÍNICO: Femenino de 66 años de edad con dolor óseo en muslo y fractura espontánea de fémur, en la que se detectaron lesiones osteolíticas, hipercalcemia, niveles elevados de fosfatasa alcalina y de paratohormona; con gammagrama que mostró un tumor funcionante localizado en mediastino superior, fue sometida a extirpación en bloque con hemitiroidectomía derecha con tumor de la glándula paratiroides. El estudio histopatológico reportó CP. DISCUSIÓN: El CP representa la neoplasia menos común; en pacientes con niveles de paratohormona mayores de 1,000 pg/ml e hipercalcemia mayor de 14 mg/dl debe sospecharse dicha patología.

[Shoulder injuries in the elderly and their functional impact on the DASH scale]. / Lesiones de hombro en la tercera edad y su repercusión funcional en escala de DASH.

INTRODUCTION: Disabling shoulder problems in the elderly are common. OBJECTIVE: To quantify the diagnoses found in 100 consecutive shoulders cases in rehabilitation and its functional impact on the DASH scale. MATERIAL AND METHODS: 100 consecutive patients with age 65 years received in the Rehabilitation Department, performing diagnosis and functional assessment in the DASH scale. RESULTS: Distribution by gender with predominance of the female (67%); the age showed variation from 65 to 98 years with average and SD 78 ± 12. Ten different diagnoses were found: supraspinatus tendon rupture (58%); gleno-humeral osteoarthritis (11%); impingement syndrome (9%); proximal humeral fracture (9%); acromio-clavicular osteoarthritis (7%); long biceps tendon rupture (2%); scapula fracture (1%); humeral head avascular necrosis (1%); neglected gleno-humeral dislocation (1%) and circumflex nerve injury (1%). The distribution corresponded to 52% right, 40% left and 8% bilateral. The DASH scale showed variation from 94 to 52% with mean and SD 71 ± 22.3. Elderly shoulder problems are associated with disability, its relation with DASH is not clear.

INTRODUCCIÓN: Los problemas discapacitantes de hombro en la tercera edad son frecuentes. OBJETIVO: Cuantificar los diagnósticos encontrados en 100 casos consecutivos en rehabilitación y su repercusión funcional en la escala de DASH. MATERIAL Y MÉTODOS: 100 pacientes consecutivos con edad 65 años recibidos en rehabilitación, se efectuó diagnóstico y valoración funcional en la escala de DASH. RESULTADOS: La distribución por género con predominio del femenino (67%); la edad mostró variación de 65 a 98 años con promedio y DE 78 ± 12; los 10 diferentes diagnósticos correspondieron a ruptura del tendón supraespino (58%); artrosis glenohumeral (11%); síndrome de pinzamiento (9%); secuelas de fractura de tercio proximal de húmero (9%); artrosis acromioclavicular (7%); ruptura del tendón de la porción larga del bíceps (2%); fractura de la escápula (1%); necrosis avascular de cabeza humeral (1%); luxación escápulo- humeral recidivante inveterada (1%) y lesión del nervio circunflejo (1%). La distribución correspondió a 52% derechas, 40% izquierdas y 8% bilaterales. La escala de DASH mostró variación de 94 a 52% con promedio y DE 71 ± 22.3. Los problemas de hombro en la tercera edad se asocian siempre a discapacidad importante.

Spatial and trophic preferences of jumbo squid Dosidicus gigas (D'Orbigny, 1835) in the central Gulf of California: ecological inferences using stable isotopes.

RATIONALE: The jumbo squid Dosidicus gigas is a fishery resource of considerable economic and ecological importance in the Mexican Pacific. Studies on its habitat preferences are needed to understand recent fluctuations in the abundance and availability of the species. Stable isotope analysis allows us to infer ecological aspects such as spatial distribution and trophic preferences. METHODS: We used an isotope ratio mass spectrometer, automated for carbonate analysis, and coupled to an elemental analyzer, to determine the isotopic composition of statoliths (δ18 O and δ13 C values) and beaks (δ13 C and δ15 N values) from 219 individuals caught over two fishing seasons (2007 and 2009) off the coast of Santa Rosalía, in the central Gulf of California. We used these isotopic ratios to assess variation in spatial and trophic preferences by sex, size, and fishing season. RESULTS: In the 2009 group, we observed significant differences in statolith δ13 C values and beak δ13 C and δ15 N values between males and females. Between size groups, we observed significant differences in statolith δ18 O and δ13 C values in 2007 and in beak δ13 C and δ15 N values during both seasons. Both seasons were characterized by high overlap in δ18 O and δ13 C values between sexes and in 2009 between size groups. We observed low trophic overlap between sexes in 2009 and between size groups during both seasons. CONCLUSIONS: The isotopic ratios from statoliths and beaks indicate that D. gigas has changed its spatial and trophic preferences, a shift that is probably related to changes in the species' diet. This intraspecific variation in preferences could be related to characteristics such as size, which may influence squid distribution preferences.

Cirugía endoscópica nasosinusal: ¿un procedimiento ambulatorio? / Endoscopic sinus surgery: a day surgery?

RESUMEN Introducción: La cirugía endoscópica nasosinusal (CEN) ha aumentado progresivamente debido a que brinda un gran acceso quirúrgico mediante un abordaje mínimamente invasivo. Debido a que tiene un posoperatorio reducido y con pocas complicaciones se puede realizar como cirugía ambulatoria (CA). Esta modalidad es ampliamente aceptada a nivel internacional, sin embargo, no se ha masificado en nuestra realidad nacional. Objetivo: Describir la incidencia y causas de estadía no programada pos CEN ambulatoria en el Servicio de Otorrinolaringología del Hospital del Salvador. Material y método: Revisión retrospectiva de fichas de pacientes operados de CEN por el mismo equipo quirúrgico (Dra. Constanza J. Valdés y Dra. Paula Ruz) entre agosto 2013 y diciembre 2015. Se registraron datos demográficos, cirugías y complicaciones perioperatorias. Resultados: De un total de 75 CEN programadas para realizarse en forma ambulatoria, la incidencia de estadía no programada fue de 15%. Las principales causas fueron problemas administrativos (6 casos) seguido de complicaciones perioperatorias (5 casos). Conclusión: Excluyendo causas administrativas de estadía no programada, el 93% de los procedimientos lograron realizarse como CA. Esta modalidad es plausible y recomendable en el sistema de salud donde los recursos son escasos.

ABSTRACT Introduction: Endoscopic sinus surgery (ESS) has an increase trend because it provides wide surgical access through a minimally invasive approach. It can be performed on a day surgery basis because it has a fast postoperative recovery and a low complication rate. This method has worldwide acceptance, however it has not been established in our national practice. Aim: Describe incidence and unplanned admission causes of ESS in the Otolaryngology service of the Hospital del Salvador. Material and method: Retrospective review of patient medical records undergoing ESS by the same surgical team (Dra. Constanza J. Valdés y Dra. Paula Ruz) between August 2013 and December 2015. Patient demographic information, surgery and perioperative complications were recorded. Results: 75 ESS procedures were scheduled to be performed on an outpatient basis. The incidence of unplanned stay was 15%. Fifteen patients had an unplanned admission, due to administrative problems (6) and perioperative complications (5). Conclusions: Fifteen percent of the patients who underwent ESS on a day surgery basis had an unplanned stay; its main cause is due to administrative problems. Excluding administrative causes of unplanned admission, 93% of the procedures performed were ambulatory procedures. This mode is plausible and desirable in the health system where resources are scarce.

Hadamard circular masks: high focal depth with high throughput.

We present a class of binary masks that encode, in polar coordinates, the values of a Hadamard matrix of order N. For order N ≥ 2, the binary masks increase the Strehl ratio vs. focus error by the factor N, with the highest possible light throughput. Since a Strehl ratio with high tolerance to defocus does not guarantee a modulation transfer function (MTF) with low sensitivity to focus errors, then, we show that for N = 16 the binary mask reduces also the impact of focus error on the MTF. Equivalently, the discrete binary mask has Fisher information with low variations to defocus.

[Iliacus muscle injury caused by inadequate exercise]. / Lesión del músculo ilíaco por ejercicio inadecuado.

BACKGROUND: Traumatic iliacus muscle injury is rare; it is usually caused by trauma or intense exercise involving the pelvic girdle; it can produce a hematoma with femoral nerve neuropathy. Spontaneous muscle hematomas occur in patients with coagulation disorders. CLINICAL CASE: A 45-year-old male with 18 days of evolution, with an intense pain in the right buttock, groin and iliac fossa, with an inability for hip flexion and ambulation caused by inadequate exercise (supine double leg lifts). On the physical examination: intense pain with bending and/or internal rotation of the right hip, positive Thomas maneuver, quadriceps rated 3/5; area of paresthesia in the right femoral nerve territory. Pelvic magnetic resonance imaging showed: right iliacus muscle tear with blood between its fibers. Initial treatment was rest and analgesics for eight days and gradual extension of the hip, axillary crutches with partial weight bearing and diathermy on the right abdominal lower quadrant, active hip exercises, bicycle and right quadriceps strengthening. The evolution was satisfactory, with full recovery in six weeks.

La lesión traumática del músculo ilíaco es rara; generalmente es causada por trauma o ejercicio intenso, que ocasiona hematoma del músculo con neuropatía del nervio femoral como complicación. Los hematomas espontáneos del mismo ocurren en pacientes con trastornos de la coagulación.

Identifying pelagic fish eggs in the southeast Yucatan Peninsula using DNA barcodes.

In the waters surrounding Banco Chinchorro in the Mexican Caribbean are spawning and nursery areas for many types of fish. In this natural environment, as opposed to under controlled laboratory conditions, it is almost impossible to link an individual egg to the adult that laid it. This makes identifying the species of the eggs difficult. However, DNA barcodes have made this easier. In the present study, 300 eggs were processed for molecular analysis, from which 139 sequences were obtained. We identified 42 taxa (33 species with their binomial names), 35 genera, and 24 families. The identified eggs included those from Ariomma melanum, which is the first recording of this species in the Mexican Caribbean. Eggs from economically important fish species were also identified, including frigate tuna (Auxis thazard), crevalle jack (Caranx hippos), common dolphinfish (Coryphaena hippurus), sailfish (Istiophorus platypterus), white marlin (Kajikia albida), skipjack tuna (Katsuwonus pelamis), blackfin tuna (Thunnus atlanticus), and swordfish (Xiphias gladius). We have also described new morphological characteristics and captured photographs for 21 species, as well as obtained new information about spawning locality and time for 16 species. This valuable information will provide the basis to develop more effective conservation measures for sustainable fisheries and protection of the Mesoamerican Barrier Reef System.

Epidemiological Characteristics of the Largest Kidney Transplant Program in Mexico: Western National Medical Center, Mexican Institute of Social Security.

BACKGROUND: According to the National Transplant Center (CENATRA), in 2013, a total of 2707 transplantations were performed in Mexico; of them, 10% (270 transplantations) were done in our Tertiary Care Hospital (Western National Medical Center). This means that one in 10 transplant recipients undergoes transplantation at our medical center. The aim of our study was to describe the characteristics of and to compare changes in the kidney transplantation program over time. MATERIALS AND METHODS: This was a cross-sectional study. Data were collected from the hospital transplant registry from January 1994 to December 2014. RESULTS: During the study period, 3643 kidney transplantations were conducted; most were living donor 3236 (89%), and only 407 patients (11%) received a graft from a deceased donor. Of living donors, 2786 (87%) were related, and 450 (13%) were genetically unrelated. The average recipient age was 28 years, and the average age of the donor was 34 years. It was observed that siblings donated more frequently (51%), followed by parents (34%). Among unrelated donors, spouses donated the most (66%). In 80% of cases, the cause of end-stage renal disease (ESRD) was unknown (80%). The most frequent renal replacement therapy was peritoneal dialysis (54%), followed by hemodialysis (18%); only 5% of patients received preemptive kidney transplant. The most frequent immunosuppression scheme was tacrolimus, mycophenolate mofetil, and prednisone in 70% of patients. CONCLUSION: The Western National Medical Center is the largest kidney transplantation program in Mexico. The main activity is living donor transplantation. Recipients are relatively young persons with unknown etiology of ESRD.

The impact of treatment on quality of life of patients with head and neck cancer and its association with prognosis.

BACKGROUND: Information is scarce regarding the impact of treatment on Health-Related Quality of Life (HRQL) of patients with Head and Neck (H&N) cancers. We assessed the effect of treatment on HRQL and its association with prognosis in H&N cancer. PATIENTS AND METHODS: Patients with H&N cancer in whom HRQL was assessed before and after treatment. The European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and QLQ-H&N35 instruments were used. Association of changes in patients' HRQL after treatment with Loco-Regional Recurrence (LRR) and Overall Survival (OS) was investigated. RESULTS: One hundred sixty patients were included; scales of the baseline assessment of HRQL were moderately associated with LRR and OS, but the impact of treatment on most HRQL scales was strongly associated with OS. By multivariate analysis, baseline assessment of Global Health, Physical, HN Teeth, HN Dry mouth, and HN Cough scales, and impact of treatment on the Physical and Pain scales comprised independent variables associated with LRR. Male gender, positive lymph nodes, baseline assessment of Role, HN Pain, HN Cough, and impact of treatment on Emotion, Pain, Financial, HN Swallowing, HN Social contact, and the interaction of HN Pain-change in Pain scales were associated with OS. Both multivariate models were adjusted by the neoplasm's site of origin. CONCLUSION: Aside from well-known clinical-pathologic prognostic factors in H&N cancers, HRQL assessment, both prior to and after treatment, provides significant prognostic information and should be measured. Design of therapeutic clinical trials in patients with H&N cancers should consider these novel prognostic factors.

Multi-level regulation of the chloroplast ATP synthase: the chloroplast NADPH thioredoxin reductase C (NTRC) is required for redox modulation specifically under low irradiance.

The chloroplast ATP synthase is known to be regulated by redox modulation of a disulfide bridge on the γ-subunit through the ferredoxin-thioredoxin regulatory system. We show that a second enzyme, the recently identified chloroplast NADPH thioredoxin reductase C (NTRC), plays a role specifically at low irradiance. Arabidopsis mutants lacking NTRC (ntrc) displayed a striking photosynthetic phenotype in which feedback regulation of the light reactions was strongly activated at low light, but returned to wild-type levels as irradiance was increased. This effect was caused by an altered redox state of the γ-subunit under low, but not high, light. The low light-specific decrease in ATP synthase activity in ntrc resulted in a buildup of the thylakoid proton motive force with subsequent activation of non-photochemical quenching and downregulation of linear electron flow. We conclude that NTRC provides redox modulation at low light using the relatively oxidizing substrate NADPH, whereas the canonical ferredoxin-thioredoxin system can take over at higher light, when reduced ferredoxin can accumulate. Based on these results, we reassess previous models for ATP synthase regulation and propose that NTRC is most likely regulated by light. We also find that ntrc is highly sensitive to rapidly changing light intensities that probably do not involve the chloroplast ATP synthase, implicating this system in multiple photosynthetic processes, particularly under fluctuating environmental conditions.