bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetics of Cerebrovascular Accidents
Authors: Alter Milton , Kluznik John 
Published: June 2011

The influence of heredity factors in Cerebrovascular accidents was investigated by studying the families of 80 patients with a clinical diagnosis of CVA. The frequency of CVA in parents and siblings of these patients was compared with the frequency in the family of the patient's spouse. The frequency of recognized predisposing illnesses to CVA including hypertension, diabetes and heart disease was also studied. The patients and the spouses were excluded from the study population.
Analysis of the data obtained on 160 parents and 384 sibs of the proband and on 140 parents and 336 sibs of the spouse revealed a frequency of CVA of 10.7% and 8.6% respectively. This difference was not statistically significant. However, when the sibs and parents were analyzed separately the difference between the sibs was significant (p < 0.025), suggesting the possibility that a small added risk of CVA existed for certain close relatives of a CVA victim.
Besides an inherited tendency to CVA, other factors were considered to account for the difference in frequency of CVA. Age, family size and differential reporting of illness failed to account for the difference. However, both hypertension and heart disease occurred with greater frequency in the sibs of the patient. When patients with these predisposing illnesses were excluded and those with CVA alone were compared, it was found that relatives of the patient and the spouse had essentially the same frequency (3.1% and 3.2% respectively). Moreover, hypertension and heart disease were significantly more common in the relatives of the proband. The excess of CVA in the sibs of the proband could, therefore, have been due to an excess of predisposing illnesses such as hypertension and heart disease, and no independent inheritance of CVA was demonstrated. In the absence of certain predisposing illness, close relatives of CVA patients appeared to have no greater risk of CVA than genetically unrelated individuals.
Can Plasma Skimming or Inconstancy of Regional Hematocrit Introduce Serious Errors in Regional Cerebral Blood Flow Measurements or Their Interpretation?
Authors: Rosenblum William I. 
Published: June 2011

Recent reports indicate that in cases of elevated plasma or blood viscosity, red cell velocity through the cerebral microcirculation is unimpaired while plasma transit is retarded. One explanation may be that plasma skimming is increased, with increased shunting of plasma into longer, less direct flow paths, while an increasing proportion of red cells take shorter paths. Such inhomogeneities of flow on a microvascular level can be directly demonstrated in cases of endothelial damage or anoxia, and may produce an altered regional hematocrit.
Measurements of regional cerebral blood flow are dependent upon regional hematocrit because this affects the tissue:blood partition coefficient (λ) of diffusible indicators. Hence changes in regional HCT may produce errors in the calculation of regional blood flow unless the value of λ. is corrected to reflect altered HCT. Moreover, no matter what kind of indicator is used, our functional interpretation of regional blood flow measurements is dependent upon our assumption that the ‘blood’ in the region maintains a constant capacity to carry nutrients like oxygen. Thus the lack of a constant relationship between plasma flow and red cell flow may produce errors either in the measurement or interpretation of regional flow measurements. These errors will increase in importance as blood flow is measured in smaller and smaller volumes of brain.
Control of Cerebral Vasospasm by Parenteral Phenoxybenzamine
Authors: FLAMM EUGENE S. , YASARGIL M. GAZI , RANSOHOFF JOSEPH 
Published: June 2011

Cerebral vasospasm has been studied in the basilar artery of the cat. The ability of alpha adrenergic blocking agents to prevent and alleviate spasm produced by the application of blood to the basilar artery has been investigated.
Parenteral phenoxybenzamine is effective in preventing spasm under these experimental conditions when given in doses of 12 mg/kg provided at least two hours elapse between the administration of the drug and the application of the blood. The drug has been found effective up to 24 hours after parenteral administration.
The systemic response to alpha adrenergic blockade and the effects on spasm of the basilar artery produced by different doses at intervals from 1 to 44 hours after the administration of the drug are presented.
Although parenteral phenoxybenzamine is effctive in preventing spasm from subarachnoid blood, it does not prevent spasm from mechanical manipulation of the vessels. This would indicate that mechanisms other than adrenergic stimulation itself may be operative in cerebral vasospasm. The alteration of spasm from blood and mechanical manipulation by other alpha adrenergic blocking agents has been studied and the possible modes of action of these drugs are discussed.
Clinical Grade, Regional Cerebral Blood Flow and Angiographical Spasm in the Monkey After Subarachnoid and Subdural Hemorrhage
Authors: PETRUK KENNETH C. , WEIR BRYCE K. A. , MARRIOTT MICHAEL R. , OVERTON THOMAS R. 
Published: June 2011

Subarachnoid and subdural hemorrhage has been induced in the anesthetized monkey by injection of fresh autogenous blood via a needle inserted through a subfrontal twist drill hole. Serial angiographical studies and regional cerebral blood flow (rCBF) determinations were carried out concurrently for three hours following hemorrhage. The changes observed were subsequently correlated with the clinical state of the animals upon reversal of anesthesia.
In general, angiographical vasospasm and a reduction in CBF occurred simultaneously. Occasionally, however, cerebral perfusion remained unaltered after SAH even though marked vasoconstriction of the intradural vessels was present. An excellent correlation between the severity of reduced perfusion and the degree of neurological deficit was found.
Stroke in Jerusalem District 1960 Through 1967: An Epidemiological Study
Authors: MELAMED ELDAD , CAHANE ESTHER , CARMON AMIRAM , LAVY SYLVAN 
Published: June 2011

An epidemiological study was performed in Jerusalem district on the incidence of new stroke patients during the years 1960 through 1967.
On the assumption that the vast majority of patients with a new cerebrovascular event were either hospitalized in one of the three local hospitals or later referred to the Neurological Outpatient Clinic at the Hadassah University Hospital, a retrospective study was performed in order to obtain a close estimation of the incidence of stroke in the district of Jerusalem. In the period of 1960 through 1967, 1,522 new stroke cases were identified and included in this study. On the basis of the history, clinical picture and auxiliary tests, the patients were divided into three groups: (1) ischemic stroke, (2) stroke due to hemorrhage, and (3) stroke of undetermined type. The criteria for differentiation of cerebral ischemia from hemorrhage were rigid, demanding at least a lumbar puncture, angiography, operation, or autopsy for a diagnosis of either one to be made. These rigid criteria account for the high percentage of undetermined cases. Ischemic stroke was diagnosed in 509 (33%), stroke due to hemorrhage in 181 (12%), and stroke of undetermined type in 832 (55%).
The average annual incidence of stroke in the district of Jerusalem was 90/100,000 population.
The age-specific annual incidence rates showed an almost constant increase for both sexes and the various types of stroke, with increasing age. The age-specific and sexspecific annual incidence rates disclosed a male preponderance for all the age groups above 45 in the "ischemic" and "undetermined" types, and for the total series. This preponderance was marked in the 65 to 74 age group. In the "stroke due to hemorrhage" type there was a slight male preponderance in the 65 to 74 age group and a slight female preponderance in the 75+ age group, the ratio being equal for the total hemorrhagic series. Our findings were compared with those reported in other studies and discussed.
The Hydrogen Clearance Method in Assessment of Blood Flow in Cortex, White Matter and Deep Nuclei of Baboons
Authors: PASZTOR EMIL , SYMON LINDSAY , DORSCH N. W. C. , BRANSTON NEIL M. 
Published: June 2011

The technique of hydrogen clearance by an inhalation method is discussed.
The electronic instrumentation necessary to secure stability and reproducibility from the recordings is described.
Clearance rates in gray matter of about 80 ml/100 gm per minute in the cortex and putamen have been obtained, and of about 20 ml/100 gm per minute in white matter.Clearance curves have invariably been monoexponential in character in white matter, and in over half the cases in the putamen. In the remainder of the putamen curves and in 60% of the cortical clearance curves, the curves could be resolved into only two exponentials. Using bicompartmental analysis, the fast-clearing components of biexponential curves in both cortex and deep nuclei gave the same figures as clearance curves of an entirely monoexponential character from these two tissues.
The importance of recirculation time, concentration of hydrogen inhalation, and verification of the tissue placement by subsequent dissection are discussed. The capacity of the method to detect sudden changes in flow during clearance is described.
Epidemiology of In-Hospital Deaths Among Black Stroke Patients
Authors: SHAFER STEPHEN Q. , BRUUN BERTEL , RICHTER RALPH W. 
Published: June 2011

Fatality rates in 527 consecutive stroke patients were compared by nine different criteria: age, sex, each of four risk factors or the absence of all, type of lesion, and initial level of consciousness. In the 527, the only significant increases (P < 0.01) in fatality rate were in older patients compared to younger patients (48% versus 34%), hemorrhages compared to infarctions (85% versus 33%), and patients with depressed sensoriums compared to alert ones (65% versus 19%). When the series was split by age (≤ 65 years, ≥ 66 years), younger hypertensives had more fatalities than normotensives (39% versus 24%, P < 0.02), while older hypertensives fared better than normotensives (45% fatalities versus 50%, not significant). For infarction alone, younger hypertensives had 21% fatalities, normotensives 16%; of older hypertensives, 39% died compared to 44% of the normotensives. These differences are not significant (P<0.25).
In this series, it appears that (1) age, initial sensorium, and type of lesion are good discriminant factors in the prognosis for life after stroke, (2) age-specific analysis may highlight other factors operating only in a certain age group, and (3) hypertension may have relatively benign associations among more elderly patients.
Stroke Surveillance: The Concept of Stroke Team in Diagnosis, Treatment and Prevention
Authors: BORHANI NEMAT O. 
Published: June 2011

The Stroke Project in the Sacramento Medical Center has had two primary objectives. These were: (1) to create an atmosphere of stroke awareness by continuous feedback of relevant and reliable information to physicians who care for stroke patients, and (2) to introduce the concept of the stroke team in daily care of the stroke patient in the hospital and beyond.
During a period of two years 171 stroke patients were admitted to the Project. The system devised provided a useful tool in planning objectively the appropriate course of action in patient education and training programs.
Regional Cerebral Blood Flow in Patients With Hypertensive Intracerebral Hemorrhage
Authors: KAWAKAMI HIROSHI , KUTSUZAWA TAKASHI , UEMURA KAZUO , SAKURAI YOSHIHARU , NAKAMURA TAKASHI 
Published: June 2011

Regional cerebral blood flow was measured by
183
Xe clearance method in 44 patients with hypertensive intracerebral hemorrhage (HIH) within three weeks from attack. Mean CBF in cases with the more disturbed consciousness was the lower value. There was no definite relationship between mean CBF and the duration from last stroke to measurement. In 44 cases, 35 showed hematoma of so-called "lateral type" and nine showed a "mesial type." There was no difference of mean CBF between these two groups. In the group with lateral-type hematoma, 14 cases were thought to show large space-occupying signs, and their mean CBF was significantly lower than that of the other 21 cases.

In 16 cases, relative hyperemic regions were observed in both the focal and nonfocal areas. In seven cases, relative ischemic regions were frequently in nonfocus rather than focus.

Response of hyperemic region to carbon dioxide was good in seven and poor in three regions in focal area, and was good in eight and poor in one region in nonfocal area. Reactivity of ischemic region to 5% CO
2
inhalation was good in three and poor in zero regions in focus, and was good in three and poor in two regions in nonfocus.

Early venous filling (EVF) was observed in 13 cases and all of them were with lateral-type hematomas.
Only four out of 13 cases showed good correlation between angiographical findings and cerebral circulation.
Cooperative Study of Intracranial Aneurysms and Subarachnoid Hemorrhage. Report on a Randomized Treatment Study
Authors: NIBBELINK DONALD W. , KNOWLER LLOYD A. 
Published: June 2011

Four selected treatments, namely, regulated bed rest, drug-induced hypotension, carotid ligation, and intracranial surgery, were randomly allocated with respect to location of the aneurysm and interval following last bleed. The objective of the Study was to answer the question. "What mode of treatment offers a patient with a single ruptured intracranial aneurysm during the previous three months the highest probability of optimal results with respect to survival. residual neurological deficit, capacity for self-care, and gainful employment? " Various treatments were suspended at specific intervals when a particular mode of therapy became inferior to the others.
A group of 33 patients was disqualified after treatment was randomly allocated. The numbers of protocols remaining for analysis within each treatment category were 202 for regulated bed rest, 309 for drug-induced hypotension, 187 for carotid ligation, and 274 for intracranial surgery.
Positive Scans in Angiographically Proved Cases of Recanalized Cerebral Infarction
Authors: IRINO TADAYOSHI , TANEDA MAMORU , MINAMI TAKAO 
Published: June 2011

In 20 patients with acute major cerebral arterial occlusion, follow-up angiograms were obtained to inspect the occluded artery. These angiograms were compared with brain scans in the fourth week after the stroke. The angiograms revealed that frequent recanalization of the occluded arteries occurred within a week after the onset. On the other hand, brain scans showed the increased uptake of radioisotopes even in the patients with angiographically demonstrated arterial recanalization.
The present study clarified that positive scans could be obtained in the patients with and without recanalization, and emphasized the diagnostic value of brain scans in the subacute or chronic stage of cerebral infarction, especially in patients with no arterial occlusion appearing on the angiograms.
Comparison of Blood Flow and Patency in Arterial and Vein Grafts to Basilar Artery
Authors: WHANG C. J. , MOZINGO J. ROBERT , RHOTON A. L. 
Published: June 2011

Blood flow and patency rates obtained by lingual to basilar artery anastomosis were compared with those obtained by saphenous vein bypass graft from the carotid to the basilar artery in two groups of ten dogs. Flow was measured by an electromagnetic technique while blood pressure and blood gases were monitored. Graft patency also was determined by angiography and histological examination. The arterial and venous grafts carried more than enough blood to maintain a normal flow (9.5 ml per minute) through the basilar system of dogs.
Immediately after anastomosis, average flow through the vein grafts was 15.5 ml per minute (range 10 to 20 ml per minute) and through the arterial anastomosis 15.6 ml per minute (range 10 to 24 ml per minute). Six weeks later, average flow through the vein graft was 11.5 ml per minute and through the arterial graft 13 ml per minute. With induced hypertension, flow increased in the arterial grafts to an average of 26.2 ml per minute and in the vein grafts 24 ml per minute. Hypercarbia increased arterial graft flow to an average of 27.8 ml per minute and vein graft flow to 23.5 ml per minute.
By angiography, graft patency was shown in only 80% of the grafts at one week and in 60% at six weeks postoperatively, even though all grafts were patent by flow and histological determinations. This failure of angiography represents a limitation of the radiographical resolution in millimeter-sized vessels.
Chronically Impaired Autoregulation of Cerebral Blood Flow in Long-Term Diabetics
Authors: BENTSEN NIELS , LARSEN BO , LASSIN NIELS A. 
Published: June 2011

Using the arteriovenous oxygen difference method autoregulation of cerebral blood flow (CBF) was tested in 16 long-term diabetics and eight control patients. Blood pressure was raise by angiotensin infusion and lowered by trimethaphan camsylate infusion, in some cases combined with head-up tilting of the patient. Regression analysis was carried out on the results in order to quantify autoregulatory capacity.
In the control patients CBF did not vary with moderate blood pressure variations, indicating normal autoregulation. In four of the 16 diabetic patients CBF showed significant pressure dependency, indicating impaired autoregulation. The cause of impaired autoregulation in some long-term diabetics is believed to be diffuse or multifocal dysfunction of cerebral arterioles due to diabetic vascular disease. Other conditions with impaired autoregulation are discussed and compared with that seen in long-term diabetes.
Exposure to Uremic Serum Induces a Procalcific Phenotype in Human Mesenchymal Stem Cells
Authors: Kramann Rafael , Couson Simone K. , Neuss Sabine , Kunter Uta , Bovi Manfred , Bornemann Jörg , Knüchel Ruth , Jahnen-Dechent Willi , Floege Jürgen , Schneider Rebekka K. 
Published: June 2011

Objective—
Medial artery calcification in patients with chronic kidney disease proceeds through intramembranous ossification resulting from osteoblast-induced calcification of the collagen extracellular matrix. The current study is based on the hypothesis that mesenchymal stem cells (MSC) constitute critical cells for procalcific extracellular matrix remodeling in patients with chronic kidney disease.

Methods and Results—
Human MSC were cultured in media supplemented with pooled sera from either healthy or uremic patients (20%). Exposure to uremic serum enhanced the proliferation of MSC (cell counting, BrdU incorporation) whereas apoptosis and necrosis were not affected (annexin V and 7-amino-actinomycin staining). Uremic serum–exposed MSC recapitulated osteogenesis by matrix calcification and expression of bone-related genes (bone morphogenetic protein [BMP]-2 receptor, alkaline phosphatase, osteopontin, and Runx2) in 35 days. The uremic serum–induced osteogenesis was completely blocked by a BMP-2/4 neutralizing antibody or the natural antagonist NOGGIN. Calcification and matrix remodeling were further analyzed in a collagen-embedded osteogenesis model recapitulating the vascular collagen I/III environment. The uremic serum–induced calcification was shown to occur along collagen fibers as shown by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and von Kossa staining and was accompanied by extensive matrix remodeling.

Conclusion—
Uremic serum induced in a BMP-2/4-dependent manner an osteoblast-like phenotype in MSC accompanied by matrix remodeling and calcification.
An Automated, Objective, Multiple-Satellite-Platform Tropical Cyclone Surface Wind Analysis
Authors: Knaff John A. , DeMaria Mark , Molenar Debra A. , Sampson Charles R. , Seybold Matthew G. 
Published: June 2011

AbstractA method to estimate objectively the surface wind fields associated with tropical cyclones using only data from multiple satellite platforms and satellite-based wind retrieval techniques is described. The analyses are computed on a polar grid using a variational data-fitting method that allows for the application of variable data weights to input data. The combination of gross quality control and the weighted variational analysis also produces wind estimates that have generally smaller errors than do the raw input data. The resulting surface winds compare well to the NOAA Hurricane Research Division H*Wind aircraft reconnaissance–based surface wind analyses, and operationally important wind radii estimated from these wind fields are shown to be generally more accurate than those based on climatological data. Most important, the analysis system produces global tropical cyclone surface wind analyses and related products every 6 h—without aircraft reconnaissance data. Also, the analysis and products are available in time for consideration by forecasters at the Joint Typhoon Warning Center, the Central Pacific Hurricane Center, and the National Hurricane Center in preparing their forecasts and advisories. This Multiplatform Tropical Cyclone Surface Wind Analysis (MTCSWA) product is slated to become an operationally supported product at the National Environmental Satellite Data and Information Service (NESDIS). The input data, analysis method, products, and verification statistics associated with the MTCSWA are discussed within.
Simple Multicloud Models for the Diurnal Cycle of Tropical Precipitation. Part I: Formulation and the Case of the Tropical Oceans
Authors: Frenkel Yevgeniy , Khouider Boualem , Majda Andrew J. 
Published: June 2011

Abstract
The variation of tropical precipitation due to the diurnal cycle of solar heating is examined here in the context of two simple models for tropical convection. The models utilize three cloud types—congestus, deep, and stratiform—that are believed to characterize organized tropical convection and are based on the two first baroclinic modes of vertical structure plus a boundary layer mode. The two models differ mainly in the way they treat the boundary layer dynamics. The first one is purely thermodynamical and is reduced to a single equation for the equivalent potential temperature θe connecting the boundary layer to the upper troposphere through downdrafts and to the surface through evaporation while the second uses full bulk boundary layer (FBBL) dynamics with a careful separation between sensible and latent heat fluxes and parameterization of nonprecipitating shallow cumulus. It turns out that in the case of the precipitation over the ocean where the Bowen ratio is small, both models yield a qualitatively similar solution, characterized by an overnight initiation and early morning peak in precipitation consistent with observations. The modeled diurnal cycle of precipitation over the ocean is divided into four cyclic phases: 1) a CAPE (re)generation phase characterized by the enhancement of the boundary layer θe and moisture fluxes during midday and early afternoon that is followed by 2) a (re)moistening phase dominated by congestus heating during the late afternoon and moistening from downdrafts (due to detrainment of shallow cumulus, specifically in the FBBL model) and radiative cooling that lasts until midnight. 3) Deep convection is initiated around midnight when the midtroposphere is sufficiently moist and cool and (re)establishes the precipitation level near its radiative convective equilibrium (1 K day−1) and then 4) peaks with sunrise at 0600 LST to yield a precipitation maximum of roughly 2 K day−1 at around 0900 LST that dries the troposphere and consumes CAPE and closes the cycle.