Regional Variations In Distribution Research Articles

Regional Variations in Distribution, Diagnosis and Treatment of Chronic Pancreatitis in Mainland China: A Systematic Review of Case Articles Over 40 Years

Background: Epidemiological data regarding the regional differences in chronic pancreatitis (CP) from the mainland of China is lacking. We aimed to gather and combine the information concerning the regional distribution, diagnosis and treatment of CP, in addition to the risk factors associated with pancreatic cancer (PaCa) and death from published articles. Methods: Case articles on CP published in three English and four Chinese databases from January 1979 to December 2018 were analysed. Findings: A total of 4,452 cases articles (containing 161,243 CP cases) were included. Almost all relevant departments of 1,557 hospitals participated in the writing of CP articles and approximately 67.2% of hospitals wrote only one article. The etiologies, symptoms, treatments, and number of cases with PaCa varied from region to region. Surgical treatment was more common in underdeveloped areas. Endoscopic therapy was mainly concentrated in developed areas and was also associated with non-alcoholic CP. PaCa detected during hospitalization was mainly related to jaundice (r = 0.35, P = 0.000), pain (r = 0.31, P = 0.000), diabetes (r = 0.20, P = 0.000), biliary diseases (r = 0.36, P = 0.000), alcoholic CP (r = 0.30, P = 0.000), conservative treatment (r = 0.37, P = 0.000) and surgical treatment (r = 0.21, P = 0.000). PaCa detected during follow-up was primarily associated with idiopathic CP (r = 0.26, P = 0.000), alcoholic CP (r = 0.23, P = 0.000), endoscopy therapy (r = 0.3, P = 0.000) and surgical treatment (r = 0.24, P = 0.000). Death during hospitalization was only related to surgery. Interpretation: Many regions have gradually formed their own unique characteristics in terms of the diagnosis and treatment of CP. However, the level of diagnosis and treatment of CP in many areas still needs to be improved. The problem of uneven distribution of medical resources needs to be resolved. Funding Statement: None. Declaration of Interests: The authors declare that there are no competing interests associated with the manuscript.

Occurrence, composition profiles and risk assessment of polycyclic aromatic hydrocarbons in municipal sewage sludge in China

A nationwide survey, including 75 sludge samples and 18 wastewater samples taken from different wastewater treatment plants (WWTPs) from 23 cities, was carried out to investigate the occurrence and composition profiles of polycyclic aromatic hydrocarbons (PAHs) in China. In total, the concentrations of ∑16PAHs in sludge ranged from 565 to 280,000 ng/g (mean: 9340 ng/g) which was at a moderate level in the world. The composition profiles of PAHs were characterized by 3- and 4-ring PAHs in textile dyeing sludge and 4- and 5-ring PAHs in domestic sludge. Significant variations in regional distribution of PAHs were observed. Both the principal components analysis and diagnostic ratios revealed that vehicle exhaust, coal and natural gas combustion were the main sources of PAHs in China. The estimated concentrations of PAHs were 3820 ng/L and 1120 ng/L in influents and effluents of the WWTPs, respectively. The high toxic equivalent quantity (TEQ) values of PAHs are ascribed to the high PAH levels. Risk quotient values (RQs) in sludge indicated that there was low potential risk to soil ecosystem after sludge had been applied one year except for indeno [1,2,3-cd]pyrene (IcdP) detected in Huaibei, Anhui province.

Risk factors associated with breast cancer among women attending a tertiary care hospital in Bangalore: a case control study

Background: Breast cancer is one of the commonest cancers in both developing and developed countries. Owing to regional variations in distribution of risk factors, there is geographical variation in incidence of breast cancer. This study was attempted to assess the modifiable and non-modifiable risk factors associated with breast cancer among women attending a tertiary care hospital.Methods: A hospital based case-control study was carried out in KMIO, Bangalore, India from May 2013 to February 2014. Newly diagnosed primary cases of female breast cancer of any age and one control per case matched by 5 years age class interval were interviewed, using a questionnaire until required sample was met. Statistical analysis was performed using SPSS software version 18.0.Results: The study population consisted of 135 cases of breast cancer and 135 controls. The mean age was 50 years (SD±10.41) and 94 (34.8%) of them belonged to 45-54 years age group. After forward logistic regression, the risk factors significant at P<0.05 were age at first pregnancy >20 years OR 4.49 (95% CI 1.21-16.62), total duration of lactation <48 months OR 7.96 (95% CI 2.20-21.68), consumption of non-vegetarian diet OR 6.96 (95% CI 1.45-33.25), BMI ≥23 OR 4.91 (95% CI 1.25-19.23) and household physical activity ≤120 minutes/day OR 8.52 (95% CI 1.98-36.64), watching television during weekends >180 minutes/day OR 4.64(95%CI 2.71-7.78).Conclusions: The modifiable risk factors of breast cancer include age at first pregnancy, total duration of lactation, non-vegetarian diet, increased BMI and lower household physical activity and non-modifiable risk factor being age at menopause.

Histomorphometrical Study on Regional Variation in Distribution of Sweat Glands in Buffalo Skin.

The study was conducted on skin of 24 buffaloes collected from slaughter house. The skin tissues were collected from dorsal, lateral, and ventral parts of head, neck, thorax, abdomen, and tail regions and fixed in 10% neutral buffered formalin. The tissues were processed for paraffin blocks preparation by acetone benzene schedule. The paraffin sections of 5-6 μm were cut with rotary microtome and stained with hematoxylin and eosin. The sweat glands in buffaloes were of saccular and simple coiled tubular type. Most of the sweat glands were associated with hair follicles and consisted of a coiled secretory portion (body) and a straight duct. The secretory portion was made up of glandular tubules, myoepithelium, and basement membrane. The duct portion had a narrow lumen and was lined by simple cuboidal epithelium. The glandular epithelium was simple squamous, simple cuboidal, or low columnar type depending upon their stage of secretary activity. Two types of sweat glands were observed, i.e., apocrine and merocrine. Large number of blood vessels and nerve fibers were observed in the vicinity of the sweat glands. In head, neck, and tail regions the maximum number of sweat glands/mm2 was observed in dorsal side which did not vary significantly (p<0.05) from lateral and ventral side. In abdomen region the number of sweat glands/mm2 was maximum on lateral region which varied significantly from ventral region (p<0.05). Overall, the maximum number of sweat glands/mm2 was in head region followed by abdomen, thorax, neck, and tail but without any significant (p<0.05) difference. Maximum sweat gland diameter was found in abdomen region followed by thorax, head, neck, and tail region.

Regional economic growth disparities: A political economy perspective

Regional differences in economic growth have been observed within many countries. Our story emphasises three region-specific factors driving growth—capital, labour and political factors. Conditional on differences in production factor (i.e., labour and capital) variations across democratic states, what role do differences in underlying “political factors” across regions play in accounting for regional growth disparities? We build a political economy model of endogenous growth where regions have the same political institutions, but experience different (and estimable) distributions over voter political biases (i.e., our “political factors”). In our model, political factors affect regional productivity as a consequence of politico-economic equilibrium. We discipline our regional growth accounting exercises by calibrating/estimating each model to American state-level economic and political-survey data. We show that the capital factor is the predominant driving force behind growth in American states. Nevertheless, regional variations in distributions of voter's political biases also account a great deal for regional growth disparities. We also evaluate how much politics would have distorted agents' welfare and regional growth, were regional economies given the opportunity to live under an efficient social planner's allocation system; and, if agents were to live under the same democratic system but where all voters have equal voting influence.

Effects of Subanesthetic Dose of Nitrous Oxide on Cerebral Blood Flow and Metabolism

Nitrous oxide, in a concentration of 50% or more, is a known cerebral vasodilator. This study investigated whether a lower dose (30%) of nitrous oxide would also increase cerebral blood flow. In addition, the authors wished to study whether the increase in cerebral blood flow was accompanied by an increase in cerebral metabolism. Multimodal Magnetic Resonance Imaging at 3T was performed, and data were obtained in 17 healthy volunteers during three inhalation conditions: medical air, oxygen-enriched medical air (40% oxygen), and 30% nitrous oxide with oxygen-enriched medical air (40% oxygen). Arterial spin labeling was used to derive the primary tissue specific hemodynamic outcomes: cerebral blood flow, arterial blood volume and arterial transit times. Magnetic Resonance Susceptometry and proton Magnetic Resonance Spectroscopy were used for secondary metabolic outcomes: venous oxygenation, oxygen extraction fraction, cerebral metabolic oxygen rate and prefrontal metabolites. Nitrous oxide in 40% oxygen, but not 40% oxygen alone, significantly increased gray matter cerebral blood flow (22%; P < 0.05) and arterial blood volume (41%; P < 0.05). Venous oxygenation increased in both oxygen and nitrous oxide conditions. Compared with medical air inhalation, nitrous oxide condition caused a significantly larger decrease in oxygen extraction fraction than 40% oxygen alone (mean [SD] 11.3 [5.6]% vs. 8.3 [5.9]% P < 0.05), while global cerebral metabolic rate and prefrontal metabolites remained unchanged. This study demonstrates that 30% nitrous oxide in oxygen-enriched air (40% oxygen) significantly increases cerebral perfusion, and reduces oxygen extraction fraction, reflecting a strong arterial vasodilatory effect without associated increases in metabolism.

Low frequency fluctuations reveal integrated and segregated processing among the cerebral hemispheres

Resting-state functional magnetic resonance imaging (fMRI) has provided a novel approach for examining interhemispheric interaction, demonstrating a high degree of functional connectivity between homotopic regions in opposite hemispheres. However, heterotopic resting-state functional connectivity (RSFC) remains relatively uncharacterized. In the present study, we examine non-homotopic regions, characterizing heterotopic RSFC and comparing it to intrahemispheric RSFC, to examine the impact of hemispheric separation on the integration and segregation of processing in the brain. Resting-state fMRI scans were acquired from 59 healthy participants to examine inter-regional correlations in spontaneous low frequency fluctuations in BOLD signal. Using a probabilistic atlas, we correlated probability-weighted time series from 112 regions (56 per hemisphere) distributed throughout the entire cerebrum. We compared RSFC for pairings of non-homologous regions located in different hemispheres (heterotopic connectivity) to RSFC for the same pairings when located within hemisphere (intrahemispheric connectivity). For positive connections, connectivity strength was greater within each hemisphere, consistent with integrated intrahemispheric processing. However, for negative connections, RSFC strength was greater between the hemispheres, consistent with segregated interhemispheric processing. These patterns were particularly notable for connections involving frontal and heteromodal regions. The distribution of positive and negative connectivity was nearly identical within and between the hemispheres, though we demonstrated detailed regional variation in distribution. We discuss implications for leading models of interhemispheric interaction. The future application of our analyses may provide important insight into impaired interhemispheric processing in clinical and aging populations.

Geostatistical analysis of the distribution of Leptosphaeria species causing phoma stem canker on winter oilseed rape (Brassica napus) in England

In June/July 2001, 2002, 2003 and 2006, regional variation in distribution of the pathogens Leptosphaeria maculans and L. biglobosa that are causally associated with phoma stem canker was surveyed on winter oilseed rape crops in England. In 2001–2003, when isolates from basal cankers were visually identified as L. maculans or L. biglobosa based on cultural morphological characteristics, 70% were L. maculans and 30%L. biglobosa. In 2001, 2002, 2003 and 2006, when amounts of DNA of each species in basal cankers were determined by quantitative PCR, the abundance of L. maculans DNA was greater than that of L. biglobosa DNA in 77% of samples. When regional differences in amounts of L. maculans and L. biglobosa DNA were mapped geostatistically, quantities of L. maculans DNA were greater in cankers from southern England and those of L. biglobosa DNA were greater in northern England. A comparison with geostatistically mapped predictions made using a weather‐based model describing stages in development of phoma stem canker epidemics suggested that these differences in Leptosphaeria populations may have been a consequence of differences in temperature after onset of leaf spotting between northern and southern England. Both PCR and morphological evidence suggested that the abundance of L. maculans in England has increased since the last surveys in the 1980s. Implications of these surveys for control of phoma stem canker are discussed.

Harm reduction product distribution in British Columbia

The British Columbia Centre for Disease Control (BCCDC) tracks the distribution of all harm reduction products subsidized by the BC government, including needles and syringes, sterile water vials, alcohol swabs, condoms, and lubricant. This study measures the distribution of harm reduction products in BC, identifies regional variation in distribution, and estimates the supply/demand ratio for needle and syringe units. Using three years of administrative data (2004-2006) from the BCCDC, the quantity of harm reduction products distributed was calculated by Health Service Delivery Area (HSDA). Regional hepatitis C virus (HCV) case report rates were calculated to reflect potential variation in IDU populations at the HSDA-level and the number of needle and syringe units distributed per reported case of HCV was calculated and ranked by HSDA. To compare the demand for sterile injecting equipment to the distribution, the number of illicit drug injections per year was approximated using established estimates of IDU populations in BC and Vancouver. Marked regional variation exists in the rates of harm reduction product distribution per 100,000 residents aged 15-64. The average number of needle and syringe units distributed annually in BC from 2004-2006 was 5,382,933. The estimated number of injections per year in BC is 24,951,144, suggesting the province distributed 21.5% of the units required to cover all illicit drug injections in the province. Harm reduction product distribution is not equitable between BC HSDAs. The current level of distribution of sterile injecting equipment is inadequate to provide a clean needle for every injection.

A Population Study of Endomyocardial Fibrosis in a Rural Area of Mozambique

Endomyocardial fibrosis is the most common restrictive cardiomyopathy worldwide. It has no specific treatment and carries a poor prognosis, since most patients present with advanced heart failure. On the basis of clinical series, regional variations in distribution have been reported within several countries in Africa, Asia, and South America, but large-scale data are lacking on the epidemiologic features and early stages of the disease. We used transthoracic echocardiography to determine the prevalence of endomyocardial fibrosis in a rural area of Mozambique. We screened a random sample of 1063 subjects of all age groups selected by clustering. Major and minor diagnostic criteria were defined, and a severity score was developed and applied. Cases were classified according to the distribution and severity of the lesions in the heart. The estimated overall prevalence of endomyocardial fibrosis was 19.8%, or 211 of 1063 subjects (95% confidence interval [CI], 17.4 to 22.2). The prevalence was highest among persons 10 to 19 years of age (28.1%, or 73 of 260 subjects [95% CI, 22.6 to 33.6]) and was higher among male than among female subjects (23.0% vs. 17.5%, P=0.03). The most common form was biventricular endomyocardial fibrosis (a prevalence of 55.5%, or 117 of 211 subjects [95% CI, 48.8 to 62.2]), followed by right-sided endomyocardial fibrosis (a prevalence of 28.0%, or 59 of 211 subjects [95% CI, 21.9 to 34.1]). Most affected subjects had mild-to-moderate structural and functional echocardiographic abnormalities. Only 48 persons with endomyocardial fibrosis (22.7%) were symptomatic. The frequency of familial occurrence was high. Endomyocardial fibrosis is common in a rural area of Mozambique. By using echocardiography, we were able to detect early, asymptomatic stages of the disease. These findings may aid in the study of the pathogenesis of the disease and in the development of new management strategies.

Foraging ecology of the Swift Parrot Lathamus discolor in the box-ironbark forests and woodlands of Victoria

The foraging ecology of the Swift Parrot Lathamus discolor in the box-ironbark forests and woodlands of Victoria was investigated over three years. We sought to identify features that characterized Swift Parrot foraging habitats. A total of 159 foraging sites was found, mainly in box-ironbark forests or nearby woodlands, and were located at a disproportionately high frequency on drainage lines, and a correspondingly low frequency on ridges. The species was observed foraging on 12 eucalypt and one Acacia species, but more than 90% of observations were of birds using Red Ironbark Eucalyptus tricarpa, Mugga Ironbark E. sideroxylon, Yellow Gum E. leucoxylon or Grey Box E. microcarpa. Nectar, lerp and other food from eucalypt foliage were frequent dietary items. Foraging and random sites were broadly similar in tree size-class structure. However, Swift Parrots selected trees in larger size classes for foraging more often than expected given the relative abundance of such trees. Larger trees flowered more reliably across the study area in all years. The habitat of the Swift Parrot in the study area is extensively fragmented and degraded, and management to increase the density of larger trees is recommended. We found considerable between-year variation in regional distribution and relative use of prinCipal tree species. The five identified regions within the study area all supported a significant percentage of the population in at least one of the three years. As a result, recovery measures will need to target important sites across the geographical extent of the study area.

Épidémiologie de la flore nasopharyngée au cours des otites moyennes aiguës de l'enfant de décembre 2000 à mars 2001

Method. – A French multicentric survey was made between December 2000 and March 2001 on 734 children (6 months–6 years) presenting with acute otitis media (AOM). Results. – A total of 1133 bacterial strains were isolated from nasopharyngeal secretions, the 3 main pathogens were S. pneumoniae (409 isolates, 36%), H. influenzae (328 isolates, 29%) and M. catarrhalis (275 isolates, 24%). The overall NP carriage rate for S. pneumoniae reached 56%. Among the 409 pneumococcal strains, 63% showed reduced susceptibility to penicillin (PRSP). Thirty two percent of PRSP isolates belonged to serotype 19, the other predominant resistant serotypes were 23, 6, 14 and 9. The analysis of PRSP strain distribution showed that resistance concerned all of France and was homogeneous, with an incidence superior to 50% in all regions, except for Alsace. H. influenzae was isolated from nasopharyngeal flora in 45% of children. 43% of H. influenzae isolates produced a β-lactamase with large variations in regional distribution (13–64 % of isolates). The overall NP carriage rate for H. influenzae was 19%. Less than 1% of H. influenzae isolates were ampicillin-resistant without producing β-lactamase. Nasopharyngeal carriage rate for M. catarrhalis was 37%, with 97% of isolates producing β-lactamase. Conclusion. – Evidence of geographical variation in the incidence of PRSP and β-lactamase-producing H. influenzae stresses the need of therapeutic policies adapted to regional epidemiology. The introduction of the heptavalent pneumococcal conjugate vaccine and the diversification of first-line antibiotherapy can only have beneficial effects in terms of cost and bacterial epidemiology.

Epidemiological features of and risk factors for infection by Streptococcus pneumoniae strains with diminished susceptibility to penicillin: findings of a French survey.

A nationwide retrospective study was performed in France to describe the susceptibility of Streptococcus pneumoniae strains to penicillin G and to identify risk factors for infection with nonsusceptible strains. From January 1991 to May 1992, 10,350 S. pneumoniae strains were recorded. The overall rate of penicillin-nonsusceptible pneumococcal (PNSP) strains was 11%; specific prevalence rates, according to the sources of the isolates, were as follows: blood, 6%; cerebrospinal fluid, 10%; lower respiratory tract, 10%; and middle ear, 18%. Large variations in regional distribution were observed. In 85% of cases, PNSP strains belonged to serogroup 23, 19, 6, 14, or 9, by order of decreasing frequency. A logistic regression model identified the following factors as being associated with PNSP infections: age of < 15 years (OR = 2.01), isolation of the organisms from the upper respiratory tract (OR = 2.36) or from sinus and middle ear (OR = 1.63), HIV infection (OR = 2.01), beta-lactam antimicrobial therapy in the previous 6 months (OR = 1.99), and nosocomial acquisition (OR = 2.12). The attributable risk of beta-lactam antimicrobial therapy in the previous 6 months was 19%, showing that suppression of this factor alone could not eradicate PNSP infections.

The epidemiology of selenium deficiency in the etiological study of endemic diseases in China

The distribution of chemical elements in rocks and soils varies widely. Selenium is one of the elements that has remarkable regional variations in distribution and bioavailability. This paper reviews the epidemiology of selenium deficiency in China in connection with the etiology of human selenium-responsive diseases, the well-defined Keshan disease (KD) and the less-well-defined Kashin-Beck disease (KBD).

Regional variations in cortical cholinergic innervation: Chemoarchitectonics of acetylcholinesterase-containing fibers in the macaque brain

There are marked regional variations in the laminar distribution and intensity of acetylcholinesterase containing fibers in cortex. These fibers were particularly prominent in the 5 major paralimbic (mesocortical) regions of the brain: the insula, the caudal orbitofrontal cortex, the temporal pole, the cingulate gyrus and the parahippocampal region. Within these 5 areas, the part of cortex which is adjacent to allocortex has the most acetylcholinesterase and there is a gradual decline towards granular isocortex. The primary sensory-motor areas have distinctive laminar patterns of enzyme distribution. For example, primary visual, auditory and somesthetic koniocortices are characterized by a salient band in layer IV. On the other hand, motor and premotor areas are characterized by a concentration of radially arranged fibers within the deeper layers of cortex. High order sensory association areas throughout the cortical mantle consistently contain the least amount of acetylcholinesterase-positive fibers. It is conceivable that these patterns reflect regional variations in the distribution of cortical cholinergic innervation. The cortical topography of cholinergic markers may be relevant to the biological organization of mood and memory and also to the pathophysiology of Alzheimer's disease and of partial epilepsy.

'Free' postsynaptic-like densities in normal adult brain: their occurrence, distribution, structure and association with subsurface cisterns.

Samples of cerebral cortex (parietal and occipital) and thalamic nuclei (ventrobasal, posterolateral, dorsal lateral geniculate) from normal, adult, aldehyde perfusion fixed mice and rats were examined by electron microscopy for the presence of free postsynaptic-like densities (FPSDs). FPSDs are plaques of intracellular paramembranous electron-dense material, ultrastructurally indistinguishable from postsynaptic densities, but not aligned with a presynaptic specialization. In a systematic survey of the neuropil around 6000 neuronal perikarya, 250 FPSDs were encountered. Almost all of these were within dendritic spines and shafts and about 90% of them were apposed by a neuronal perikaryon, the remainder by a dendritic shaft. In every case a subsurface cistern (SSC) was present in the cell body or dendrite apposed to the FPSD, and was flattened along the extent of the FPSD. In none of the material were the FPSDs associated, even remotely, with degenerating elements, suggesting that they are not formed by degeneration of presynaptic boutons. The incidence of FPSD-SSC complexes was higher in thalamus than in cerebral cortex which, together with previous observations indicating their absence from normal cerebellar cortex, suggests significant regional variations in distribution. It is suggested that FPSDs might represent synaptic precursors perhaps induced to form as a response to loss (possibly age-dependent loss) of synaptic contacts on a neuron and that the SSCs are somehow involved in maintaining the FPSDs and/or preparing them for innervation by adjacent axon terminals to form new synaptic contacts.

Regional cerebral blood flow in patients with aneurysms: estimation by Xenon 133 inhalation.

Seventy six regional cerebral blood flow (rCBF) studies were conducted on 32 patients who had a total of 39 aneurysms. Twenty three of these patients were studied pre- and post-operatively. Normal values were obtained from a control group of 33 subjects, each of whom underwent one rCBF study. Flow was reduced following subarachnoid hemorrhage (SAH); it increased significantly post-operatively. Lower flows were associated with poorer clinical grades. There was a greater variation in regional distribution of flow immediately following SAH than in normals or in patients who had recovered from the acute phase. rCBF studies correlated with CT scans demonstrated that a progressive increase in ventricular size was accompanied by a progressive reduction in flow. In addition, intraventricular hemorrhage (IVH) was associated with a significant reduction in cerebral blood flow (CBF). No significant correlation between CBF and spasm was demonstrable.

Glutamate decarboxylase activity in preoptic and hypothalamic nuclei of the rat.

Freeze-dried samples were used for the determination of glutamate decarboxylase activity in discrete preoptic and hypothalamic nuclei. The activity showed marked regional variation in distribution.