13 research outputs found
Mortality of emergency abdominal surgery in high-, middle- and low-income countries
Background: Surgical mortality data are collected routinely in high-income countries, yet virtually no low- or middle-income countries have outcome surveillance in place. The aim was prospectively to collect worldwide mortality data following emergency abdominal surgery, comparing findings across countries with a low, middle or high Human Development Index (HDI).
Methods: This was a prospective, multicentre, cohort study. Self-selected hospitals performing emergency surgery submitted prespecified data for consecutive patients from at least one 2-week interval during July to December 2014. Postoperative mortality was analysed by hierarchical multivariable logistic regression.
Results: Data were obtained for 10 745 patients from 357 centres in 58 countries; 6538 were from high-, 2889 from middle- and 1318 from low-HDI settings. The overall mortality rate was 1⋅6 per cent at 24 h (high 1⋅1 per cent, middle 1⋅9 per cent, low 3⋅4 per cent; P < 0⋅001), increasing to 5⋅4 per cent by 30 days (high 4⋅5 per cent, middle 6⋅0 per cent, low 8⋅6 per cent; P < 0⋅001). Of the 578 patients who died, 404 (69⋅9 per cent) did so between 24 h and 30 days following surgery (high 74⋅2 per cent, middle 68⋅8 per cent, low 60⋅5 per cent). After adjustment, 30-day mortality remained higher in middle-income (odds ratio (OR) 2⋅78, 95 per cent c.i. 1⋅84 to 4⋅20) and low-income (OR 2⋅97, 1⋅84 to 4⋅81) countries. Surgical safety checklist use was less frequent in low- and middle-income countries, but when used was associated with reduced mortality at 30 days.
Conclusion: Mortality is three times higher in low- compared with high-HDI countries even when adjusted for prognostic factors. Patient safety factors may have an important role. Registration number: NCT02179112 (http://www.clinicaltrials.gov)
Size and degeneration increase in herring bodies during aging in hamsters
The hypothalamo-neurohypophysial tract of young, adult and aged male hamsters was studied at lateral and ventral regions of hypothalamus by means of electron microscopy. Neurosecretory swelling axons (Herring bodies) were usually found as classically described containing abundant neurosecretory granules, mitochondria, few microtubules and profiles of smooth endoplasmic reticulum in al1 groups of age. However, in aged hamsters, starting at 18-month-old subjects, we observed that the size of some neurosecretory axons was highly increased. Autophagic and degenerative features were seen in the larger ones. These data could suggest abnormal axonal storage or axonal transport blocked during aging. The implications in the role of hypothalamus- neurohypophysial system during aging are discussed
Size and degeneration increase in herring bodies during aging in hamsters
The hypothalamo-neurohypophysial tract of
young, adult and aged male hamsters was studied at
lateral and ventral regions of hypothalamus by means of
electron microscopy. Neurosecretory swelling axons
(Herring bodies) were usually found as classically
described containing abundant neurosecretory granules,
mitochondria, few microtubules and profiles of smooth
endoplasmic reticulum in al1 groups of age. However, in
aged hamsters, starting at 18-month-old subjects, we
observed that the size of some neurosecretory axons was
highly increased. Autophagic and degenerative features
were seen in the larger ones. These data could suggest
abnormal axonal storage or axonal transport blocked
during aging. The implications in the role of hypothalamus-
neurohypophysial system during aging are
discussed
Ultrastructural study of a special type of ependymal cell at paraventricular level of the golden hamster third ventricle
The present paper describes the presence of a
special cell located in the ependymal wall at the level of
the paraventricular nucleus. At this level, ultrastructural
obsewation of these ependymal cells, unlike most other
mammalian species, shows the presence of nucleoluslike
bodies in their cytoplasm and occasionally basal
processes. These processes appear perpendicular to the
ependymal surface and end in contact with the basal
membrane of hypothalamic capillaries. Mitochondria,
endoplasmic reticulum and numerous filaments are
present in the basal processes. Nucleolus-like bodies or
nematosomes consist of round or ovoid unbound masses
of granular appearing material of variable density
located in the apical cytoplasm of the cells. Some of
their ultrastructural characteristics are similar to other
ependymal specialized cells which are classically termed
tanycytes. These findings point out the possibility that
those special cells may also be implicated in a ventricleblood
vessel communication
Cell populations in the pineal gland of the viscacha (Lagostomus maximus). Seasonal variations
Pineal samples of the viscacha, which were
taken in winter and in summer, were analysed using both
light and electron microscopy. The differences found
between the two seasons were few in number but
significant. The parenchyma showed two main cell
populations. Type I cells occupied the largest volume of
the pineal and showed the characteristics of typical
pinealocytes. Many processes, some of which were filled
with vesicles, could be seen in intimate contact with the
neighbouring cells. The presence in the winter samples
of “synaptic” ribbons and spherules, which were almost
absent in the summer pineals, suggests a seasonal
rhythm. These synaptic-like structures, as well as the
abundant subsurface cisterns present in type I cells,
appeared as basic differential features which allowed
these cells to be distinguished from type II cells. These
latter cells, which can be classified as interstitial cells,
showed some other distinguishing features, such as
irregular-shaped nuclei, abundant deposits of glycogenlike
particles and structures of unknown function
consisting of concentric cisterns surrounding a dense
body. In the summer, interstitial cells displayed
numerous large round bodies, which contributed to
increase the cellular volume slightly. Regarding other
constituents, like glial cell processes, vessels of nonfenestrated
endothelium and sympathetic innervation, no
qualitative differences were observed between the two
seasons studied.
We have presented here some morphological evidences of the circannual rhythm of the viscacha
pineal, as well as ultrastructural criteria for
distinguishing the main cell populations of this organ,
which could be useful for studies carried out in other
mammals
New insights into the cytodynamics of the hamster Harderian gland as provided by the bromodeoxyuridine-labelling met hod
The fourth week of postnatal life is a critica1
point in the development of the hamster Harderian
gland. During this week, cells with large lipid vacuoles
(type-11 cells) appear in the male gland, marking a
morphological sex difference that is notorius in adult
animals. The origin and fate of type-11 cells are
controversial. To gain insight into the mechanisms by
which type-11 cells become a major cell type in the gland
of adult male hamsters, bromodeoxyuridine (BrdU)
labelling was used to assess the proliferative activity of
both types of glandular cells in 28-day-old animals. To
search for possible sex differences in the proliferative
activity of this gland, female animals of the same age as
the males were also studied. No difference was found in
the overall labelling index (BrdU-labelled cells/100
cells) between males (1.8f 0.1%) and females
(1.5+0.1%). In the gland of the males, the specific
labelling index of type-11 cells (3.4+0.4%) was
significantly higher than that of type-1 cells (0.9+0.2%).
Interestingly, the proportion of type-11 cells present in
the male glands at this age (36.6%) was significantly
lower than that of type-1 cells. Our results strongly
suggest that the proliferation of type-11 cells, rather than
a continuous differentiation of these cells from
preexisting type-1 cells, is a major event in the
achievement of the mature form of this gland. The
results reported here counsel a reappraisal of current
theories about the cytodynamics of the hamster
Harderian gland
Age-related morphometric changes in the pineal gland. A comparative study between C57BLI6J and CBA mice
Relatively little is known about the effects of
melatonin on the aging of the pineal, the organ which is
the main place for synthesis of this hormone. Using
simple morphometric methods, some parameters of the
pineal gland, such as total volume, number of
pinealocytes and pinealocyte volume were estimated in
two mice strains: normal CBA and melatonin-deficient
C57BLl6J. Two age groups, 6 weeks and 10 months,
were studied in order to evaluate possible differential
age-related changes between both strains. Pineals of both
strains have similar morphometric and morphological
features at 6 weeks of age. This suggests that pineal
development, which has already concluded at 6 weeks of
age, is not affected by the absence of melatonin
synthesis in the pinealocytes. Later on, CBA pineal
showed an increase in size caused by cellular
hypertrophy. In contrast, the C57BLl6J pineal volume
decreased by loss of pinealocytes in the same period of
time. Semithin sections analysed by light microscopy did
not show that this cell death was evident in the
C57BL16J strain at any of the ages studied. Thus, a
gradual loss of pinealocytes could be hypothesised in
these pineals. These results suggest that pineal melatonin
could have a role in the maintenance of pinealocyte
viability and the increase of pineal size which takes
place after development. The abnormal pattern observed
in the C57BL16J pineal should be taken into account in
future studies on this gland