Assessing the exposure risk of large pelagic fish to oil spills scenarios in the deep waters of the Gulf of Mexico.

Exposure risk is assessed based on modeling suitable habitat of large pelagic fish and oil spill scenarios originating at three wells located in the western GM's deep waters. Since the fate of the oil depends on the oceanographic conditions present during the accident, as well as the magnitude and duration of the spill, which are not known a priori, the scenarios used are a statistical representation of the area in which oil spilled from the well could be found, given all possible outcomes. The ecological vulnerability assessment identified a subset of bony fish with low-medium vulnerability and elasmobranchs with medium-high vulnerability. The oiling probability and exposure risk of both bony fish and elasmobranchs hotspots vary by well analyzed. Thus, these results provide essential information for a risk management plan for the assessed species and others with economic or conservation importance distributed in the GM and worldwide.

Reproductive cycle and maternal-embryonic nutritional relationship of shovelnose guitarfish Pseudobatos productus in the Gulf of California.

Samples of the shovelnose guitarfish Pseudobatos productus were collected on board a vessel and at landings of artisanal commercial fisheries in the Gulf of California from May 2004 to June 2007. Samples of 650 females, 2047 embryos and 484 uterine eggs were examined. The reproductive cycle is annual, ovulation and parturition occur in July, the uterine eggs are in diapause for 9 months (July-March) before an accelerated growth of embryos of 3 months. Histological analyses of the uterine wall of pregnant females suggested that no secretions were used for embryo nourishment. The standard percentage of water content was 48·6% in fertilized eggs and 80·75% in full-term embryos. Dry mass loss during embryonic development was 16·3% and the chemical balance of development was 0·84. This indicates that P. productus is a strictly lecithotrophic, viviparous species, that makes no maternal contribution of nutrients during embryonic development.

Mercury and arsenic in muscle and liver of the golden cownose ray, Rhinoptera steindachneri, Evermann and Jenkins, 1891, from the upper Gulf of California, México.

Mercury and arsenic levels in muscle and liver of Rhinoptera steindachneri were determined in organisms collected in 2006. Element concentrations in both tissues were directly related to size. Maxima mean concentrations of Hg and As (0.41 and 59.9 microg g(-1) dry wt, respectively) were found in adults muscle. Mercury concentrations were significantly different between juveniles and adults in muscle and liver. For As concentrations, differences between juveniles and adults were found only in muscle. Mercury concentrations were higher in muscle of juveniles and adults. Arsenic concentrations were higher in liver of juveniles, and in muscle of adults. Maximum Hg concentration in muscle (0.65 microg g(-1) dry wt) was below the safe limit established by Mexican regulations for seafood.

The fish species composition and variation of catch from the small-scale gillnet fishery before, during and after the 1997-1998 ENSO event, central Mexican Pacific.

In the tropical and subtropical coastal zone, were highly diverse fish communities occur, it is important to study the small scale fisheries exploiting these communities. For this study, 219 fishing days were carried out in Bahia de Navidad, Jalisco, Mexico. Four gillnets with different mesh sizes (76.2, 88.9, 101.6 and 114.3 mm) were used for the fishing operations, from April 1994 to March 1995 and from January 1998 to December 2000. A total of 26126 organisms weighting 11680 kg were caught. One hundred and eighty three species belonging to 57 families and 19 orders were identified. Ten species accumulated more than 60% of the total abundance and biomass, the remaining species (173) individually contributed with less than 2% of the total abundance and biomass. The most important species in the catch were Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Scomberomorus sierra, C. caninus, C. sexfjasciatus, Lutjanus guttatus and L. argentiventris. The catch per unit of effort showed a large variation during the study, both in number and biomass. On average, 110 fishes and 48.5 kg fishing day(-1) were caught. The maximum values were recorded during January and October 1998 (250 fishes and 100 kg fishing day(-1)), and the minimum values were recorded during September and November 1994 (25 org. and 10 kg fishing day(-1)). The total abundance and biomass was lower during the 1994-95 period (F=6.16, 8.32, P<0.05). There were statistically significant differences among the annual catch from each gillnet. All the environmental changes caused by the ENSO event had ecological and economic effects that can be rated from moderate to severe.

The fish species composition and variation of catch from the small-scale gillnet fishery before, during and after the 1997-1998 ENSO event, central Mexican Pacific

In the tropical and subtropical coastal zone, were highly diverse fish communities occur, it is important to study the small scale fisheries exploiting these communities. For this study, 219 fishing days were carried out in Bahia de Navidad, Jalisco, Mexico. Four gillnets with different mesh sizes (76.2, 88.9, 101.6 and 114.3 mm) were used for the fishing operations, from April 1994 to March 1995 and from January 1998 to December 2000. A total of 26126 organisms weighting 11680 kg were caught. One hundred and eighty three species belonging to 57 families and 19 orders were identified. Ten species accumulated more than 60% of the total abundance and biomass, the remaining species (173) individually contributed with less than 2% of the total abundance and biomass. The most important species in the catch were Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Scomberomorus sierra, C. caninus, C. sexfjasciatus, Lutjanus guttatus and L. argentiventris. The catch per unit of effort showed a large variation during the study, both in number and biomass. On average, 110 fishes and 48.5 kg fishing day(-1) were caught. The maximum values were recorded during January and October 1998 (250 fishes and 100 kg fishing day(-1)), and the minimum values were recorded during September and November 1994 (25 org. and 10 kg fishing day(-1)). The total abundance and biomass was lower during the 1994-95 period (F=6.16, 8.32, P<0.05). There were statistically significant differences among the annual catch from each gillnet. All the environmental changes caused by the ENSO event had ecological and economic effects that can be rated from moderate to severe.

Se llevaron a cabo 219 días de pesca experimental en la Bahía de Navidad, Jalisco, México. Se utilizaron cuatro redes de enmalle de diferente luz de malla (76.2, 88.9, 101.6 and 114.3 mm de luz de malla), de abril de 1994 a marzo de 1995 y de enero de 1998 a diciembre de 2000. En total se capturaron 26126 organismos que pesaron 11680 kg. Fueron identificadas 183 especies pertenecientes a 57 familias y 19 órdenes. Diez especies acumularon más del 60% de la abundancia y biomasa total, el resto de las especies (173) individualmente aportaron menos del 2% de la abundancia y biomasa total. Las especies más importantes en la captura fueron Microlepidotus brevipinnis, Caranx caballus, Haemulon flaviguttatum, Scomberomorus sierra, C. caninus, C. sexfasciatus, Lutjanus guttatus y L. argentiventris. La captura por unidad de esfuerzo mostró una gran variación durante todo el periodo de estudio, tanto en número de organismos como en biomasa. En promedio se capturaron 110 organismos/día de pesca (48.5 kg/día de pesca). Los valores máximos se registraron durante enero y octubre de 1998 (250 peces y 100 kg por día de pesca), y el mínimo se registró durante septiembre y noviembre de 1994 (25 organismos y 10 kg por día de pesca). La abundancia y biomasa total fue menor durante el periodo 1994-1995 (F=6.16, 8.32, P<0.05). Se encontraron diferencias estadísticamente significativas entre la captura anual de las diferentes redes. Los cambios ambientales provocados por el evento ENOS tuvo efectos que pudieran considerarse de moderados a severos, tanto ecológicos como económicos.

Usefulness of neuroendoscopy in treating supracollicular arachnoid cysts--case report.

A 12-year-old girl presented with a supracollicular arachnoid cyst manifesting as a compressive headache. Neurological examination on admission revealed no deficit except bilateral papilledema. Stereotactic cyst puncture failed to perforate the cyst wall. The wall was then punctured using microforceps under neuroendoscopic guidance, followed by cystoperitoneal shunting. Her headache disappeared immediately after surgery. Neuroendoscopy is useful in treating a deep-seated arachnoid cyst.

[A case of cranial osteomyelitis after head injury with exaggeration and remission for thirty years].

We report a case of cranial osteomyelitis after head injury with exaggeration and remission for 30 years. A 41-year-old man was referred to our hospital with redness, swelling and pain in the left frontal region. He had noted a hard mass in the same region after an injury at the age of 12 years, and local heat and redness again in the same region which had disappeared without definite treatment at the age of 20 years. Presently, skull roentogenogram showed an erosive lesion in the left frontal bone. Plain CT revealed bone defect, epidural mass lesion, calcification of the dura mater and thickness of the extracranial soft tissue in the left frontal region. T1-weighted MR images showed an isointense lesion and T2-weighted MR images showed a high intensity lesion in the inner table and a diploic layer in the left frontal bone. 99thTc MDP bone scinntigram showed abnormal uptake in the same region. Operation performed through a left frontotemporal craniotomy revealed a degeneration of temporal muscle and frontal bone, and granulation tissue and pus in the subcutaneous and epidural spaces. These were removed together with the calcified dura mater. The subdural space was intact. Dural plasty was performed using fascia lata, but the craniotomied bone was replaced. Histological examination revealed typical findings of osteomyelitis. Postoperative course was uneventful, and he was discharged without neurological deficit. Cranioplasty was performed 8 months after the first surgery. The mechanism by which osteomyelitis continued over a long course of time was suspected to be the formation of a focus of recurrent inflammation due to the head injury 30 years earlier.

Comparing postgraduate medical education at university and non-university hospitals in Japan.

In 1988 the authors surveyed all the teaching hospitals in Japan to evaluate the present status of postgraduate medical education (PGME); they received responses from 67 (84%) of the university and 172 (89%) of the non-university teaching hospitals. It was found that a large proportion of residents had spent two years in a residency without having had a single experience of some of the basic clinical skills. Consequently the residents' confidence in their abilities to perform these skills was low. The residents at the university hospitals, in particular, had had fewer experiences and were less confident about their clinical skills than were the residents at the non-university hospitals. The lack of standard and minimum requirements for PGME in Japan may be the cause of the poor level of acquisition of clinical skills of residents during PGME. Other possible causes are the tendency in Japanese medical society to attach greater importance to academic attainment than to clinical competence and the excessive gravitation of residents toward university hospitals. The authors suggest their results show the necessity to improve the training in basic clinical skills in PGME in Japan, especially in university hospitals.

Glycated hemoglobin in fractionated erythrocytes.

Erythrocytes were fractionated, by centrifugation, on the basis of cell density, which is proportional to cell age. Glycated hemoglobin (Hb A1c) in the fractionated cells was measured and compared with the Hb A1c in whole blood and with the fructosamine concentrations in plasma of normal and diabetic subjects. In normal subjects, Hb A1c increased according to the age of the erythrocytes, but hyperbolically rather than linearly, indicating the slow conversion of Hb A to Hb A1c with saturability. The greatest correlation of Hb A1c with plasma fructosamine was in younger middle-aged cells. A subgroup of subjects with impaired glucose tolerance had high Hb A1c in older cells. Hb A1c of the young cells reflects recent glycemic status, for monitoring the initial stage of the treatment of diabetics, whereas Hb A1c of the older middle-aged cells more specifically reflects the longer term glycemic status, for screening and for the long-term monitoring index for treatment of diabetes.