Challenges with pediatric surgical financing and universal health coverage in Guatemala: A qualitative analysis

The financing of surgical care for children in low- and middle-income countries (LMICs) remains challenging and may restrict adherence to universal health coverage (UHC) frameworks. Our aims were to describe Guatemala's national pediatric surgical financing structure, to identify financing challenges, and to develop recommendations to improve the financing of surgical care for children. We conducted a qualitative study of the financing of surgical care for children in Guatemala's public health system with key informant interviews (n = 20) with experts in the medical, financial, and political health sectors. We used this data to generate recommendations to improve surgical care financing for children. We identified several systemic challenges to the financing of surgical care for children, including passive purchasing structures, complex political contexts, health system fragmentation, widespread use of informal fees for surgical services, and lack of earmarked funding for surgical care. Patient and provider challenges include lack of provider input in non-personnel funding decisions, and patients functioning as both financing agents and beneficiaries in the same financing stream. Key recommendations include reducing health finance system fragmentation through resource pooling, increasing earmarked funding for surgical care with quantifiable outcome measures, engagement with clinical providers in non-personnel budgetary decision-making, and use of innovative financing instruments such as resource pooling. Surgical financing for children in Guatemala requires substantial remodeling to increase access to timely, affordable, and safe surgical care and improve alignment with Guatemala's UHC scheme.

Implementation challenges to patient safety in Guatemala: a mixed methods evaluation

BACKGROUND

Little is known about factors affecting implementation of patient safety programmes in low and middle-income countries. The goal of our study was to evaluate the implementation of a patient safety programme for paediatric care in Guatemala.

METHODS

We used a mixed methods design to examine the implementation of a patient safety programme across 11 paediatric units at the Roosevelt Hospital in Guatemala. The safety programme included: (1) tools to measure and foster safety culture, (2) education of patient safety, (3) local leadership engagement, (4) safety event reporting systems, and (5) quality improvement interventions. Key informant staff (n=82) participated in qualitative interviews and quantitative surveys to identify implementation challenges early during programme deployment from May to July 2018, with follow-up focus group discussions in two units 1 year later to identify opportunities for programme modification. Data were analysed using thematic analysis, and integrated using triangulation, complementarity and expansion to identify emerging themes using the Consolidated Framework for Implementation Research. Salience levels were reported according to coding frequency, with valence levels measured to characterise the degree to which each construct impacted implementation.

RESULTS

We found several facilitators to safety programme implementation, including high staff receptivity, orientation towards patient-centredness and a desire for protocols. Key barriers included competing clinical demands, lack of knowledge about patient safety, limited governance, human factors and poor organisational incentives. Modifications included use of tools for staff recognition, integration of education into error reporting mechanisms and designation of trained champions to lead unit-based safety interventions.

CONCLUSION

Implementation of safety programmes in low-resource settings requires recognition of facilitators such as staff receptivity and patient-centredness as well as barriers such as lack of training in patient safety and poor organisational incentives. Embedding an implementation analysis during programme deployment allows for programme modification to enhance successful implementation.

Worldwide prevalence of suicidal ideation and suicide plan among people with schizophrenia: a meta-analysis and systematic review of epidemiological surveys

Schizophrenia is a severe psychiatric disorder with high premature mortality rates. This is a meta-analysis and systematic review of the prevalence of suicidal ideation (SI) and suicide plan (SP) among people with schizophrenia. PubMed, Web of Science, Embase, and PsycINFO were systematically searched from their respective inception to October 10, 2020. Data on prevalence of SI and/or SP were synthesized using the random effects model. Twenty-six studies covering 5079 people with schizophrenia were included for meta-analysis. The lifetime and point prevalence of SI were 34.5% (95% CI: 28.2-40.9%), and 29.9% (95% CI: 24.2-35.6%), respectively. The lifetime prevalence of SP was 44.3% and the point prevalence of SP ranged between 6.4 and 13%. Subgroup and meta-regression analyses revealed that source of patients, survey countries, and sample size were significantly associated with the point prevalence of SI, while male proportion and quality assessment scores were significantly associated with the lifetime and point prevalence of SI. Survey time and mean age were significantly associated with lifetime prevalence of SI. Both SI and SP are common in people living with schizophrenia, especially in males and inpatients. Routine screening and effective interventions for SI and SP should be implemented in this population.

Knowledge and awareness of COVID-19 among Indonesian migrant workers in the Greater China Region

OBJECTIVES

Migrant workers are one of the most vulnerable population groups during the coronavirus disease 2019 (COVID-19) pandemic. This study investigated knowledge and awareness of COVID-19 among Indonesian migrant workers (IMWs) in Macao (SAR), Hong Kong (SAR), and Taiwan.

STUDY DESIGN

This was a cross-sectional study.

METHODS

Data were collected through an online survey in February and March 2020 to gain information on (1) participants' sociodemographic characteristics, (2) experience and awareness regarding COVID-19 information, and (3) knowledge and understanding of COVID-19. A series of Chi-squared, t-test, and logistic regression analyses were conducted.

RESULTS

The survey was completed by 491 participants (92.1% female). Knowledge of COVID-19 was obtained from multiple sources, including a large proportion from online social media. However, participants who obtained information from their employer, local social networks, and migrant organisations answered a greater number of questions correctly. One-third of participants reported receiving hoax, fake news, and incorrect information and obtained information from unverified sources. Participants were most interested in information about how to cure COVID-19, and 57.8% knew that no specific drug or vaccine was currently available. Almost all participants correctly identified fever and wearing a facemask as the main COVID-19 symptom and prevention strategy, respectively. Participants with senior high school or higher education and who worked as domestic or care workers had a greater knowledge of COVID-19 than their counterparts.

CONCLUSIONS

Public health communication strategies using multiple channels, including employers and community organisations, would help to minimise COVID-19 knowledge gaps. In addition, it is recommended that digital literacy content is added to public health campaigns.

Long‐term hematologic and clinical outcomes of splenectomy in children with hereditary spherocytosis and sickle cell disease

Background

Total splenectomy (TS) and partial splenectomy (PS) are used for children with congenital hemolytic anemia (CHA), although the long-term outcomes of these procedures are poorly defined. This report describes long-term outcomes of children with CHA requiring TS or PS.

Procedure

We collected data from children ages 2-17 with hereditary spherocytosis (HS) or sickle cell disease (SCD) requiring TS or PS from 1996 to 2016 from 14 sites in the Splenectomy in Congenital Hemolytic Anemia (SICHA) consortium using a prospective, observational patient registry. We summarized hematologic outcomes, clinical outcomes, and adverse events to 5 years after surgery. Hematologic outcomes were compared using mixed effects modeling.

Results

Over the study period, 110 children with HS and 97 children with SCD underwent TS or PS. From preoperatively compared to postoperatively, children with HS increased their mean hemoglobin level by 3.4 g/dL, decreased their mean reticulocyte percentage by 6.7%, and decreased their mean bilirubin by 2.4mg/dL. Hematologic improvements and improved clinical outcomes were sustained over 5 years of follow-up. For children with SCD, there was no change in hemoglobin after PS or TS following surgery, although all clinical outcomes were improved. Over 5 years, there was one child with HS and 5 children with SCD who developed post-splenectomy sepsis.

Conclusions

For children with HS, there are excellent long-term hematologic and clinical outcomes following either PS or TS. Although hemoglobin levels do not change after TS or PS in SCD, the long-term clinical outcomes for children with SCD are favorable.

Developing a national patient safety plan in Guatemala

Objective.

Patient safety is challenging for health systems around the world, particularly in low-and middleincome countries such as Guatemala. The goal of this report is to summarize a strategic planning process for a national patient safety plan in Guatemala.

Methods.

This strategic planning process involved multiple stakeholders, including representatives of the Guatemala Ministry of Health and Social Assistance, medical leadership from across the public health system, and academic experts from Guatemala and the United States of America. We used mixed methods (quantitative and qualitative surveys) and a nominal group technique at a national symposium to prioritize patient safety challenges across Guatemala, and subsequent meetings to develop a national patient safety plan.

Results.

This national patient safety plan outlines four domains to advance patient safety across the public hospital system over a five-year period in Guatemala: leadership and governance, training and awareness, safety culture, and outcome metrics. For each domain, we developed a set of goals, activities, outputs, and benchmarks to be overseen by the Ministry of Health.

Conclusions.

With this national patient safety plan, Guatemala has made a long-term commitment to improving patient safety across the public hospital system of Guatemala. Future efforts will require its extension to all levels of the Guatemalan health system.

Osteoarthritis pain and weather

OBJECTIVE

To evaluate the association between weather (barometric pressure, precipitation and temperature) and pain among individuals with osteoarthritis (OA) (n=154) at the following sites: neck, hand, shoulder, knee and foot.

METHODS

This prospective study evaluated men and women, aged 49-90 yr, participating in a community-based, osteoarthritis exercise study (June 1998-January 2002). Weekly self-reported pain scores were collected using a visual analogue scale. Statistical tests, including regression and correlation analyses, were conducted. P values < 0.001 were considered significant.

RESULTS

The total number of pain recordings varied by site, ranging from 2269 (feet) to 6061 (hands). The mean temperature was 23 degrees C with a low of 0 degrees C and a high of 36 degrees C. Precipitation levels ranged from 0.00-21.08 cm, with a mean of 0.36 cm. Most associations explored produced non-significant findings. However, among women with hand OA, higher pain was significantly associated with days of rising barometric pressure (P < 0.001).

CONCLUSION

Among a population of exercisers aged 49 yr and older, overall these findings did not support the hypothesis that weather is associated with pain. While some associations were suggestive of a relationship, largely these findings indicate that weather is quite modestly, if at all, associated with pain from OA.

Smoking and osteoarthritis: is there an association? The Clearwater Osteoarthritis Study

OBJECTIVE

To evaluate the association between cigarette smoking and the subsequent development of osteoarthritis (OA) at four separate sites: knee, hand, foot and cervical spine.

METHODS

This cohort study examined 2505 men and women aged 40 years and older participating in the longitudinal Clearwater Osteoarthritis Study (1988-current). Biennial physical exams, including serial radiographs, as well as historical information, were collected. The Lawrence and Kellgren ordinal scale was used to determine radiological evidence of the study outcome, OA. Self-reported history of smoking behavior was used to determine the study exposure. Smoking was classified using four approaches: (1) ever/never, (2) former/never, (3) current/never, and (4) dose.

RESULTS

Among the individuals at study entry, radiologically confirmed incident OA was detected during the follow-up period at four sites: knee (32%), hand (49%), foot (28%), and cervical spine (52%). Approximately 11% were self-reported current smokers. Unadjusted analyses indicated that individuals classified as current smokers demonstrated significant levels of protection from OA at all four sites investigated. However, adjusted point estimates ranging from 0.60-1.48 were suggestive of no association between smoking and the development of OA at any of the four sites investigated.

CONCLUSION

Based upon the findings of this prospective study, smoking does not appear to convey a clinically significant level of protection against the development of radiologically-confirmed OA. While these findings corroborate previous studies indicating no association between smoking and OA, anecdotal evidence warrants investigation into the role that cigarette smoking may play in the symptomatology of OA.

History of acute knee injury and osteoarthritis of the knee: a prospective epidemiological assessment. The Clearwater Osteoarthritis Study

OBJECTIVE

To evaluate the association between acute joint injury to the knee and knee osteoarthritis (OA).

DESIGN

Prospective cohort. Sample size = 1,436. Men and women aged 40 years and older participating in the population-based Clearwater Osteoarthritis Study (1988-current) with biennial physical exams including serial radiographs. Radiologically confirmed knee OA = 27%; self-reported knee injury = 11%. Lawrence and Kellgren ordinal scale was used to determine radiological evidence of the study outcome, knee OA. Self-reported history of knee injury was used to determine the study exposure.

RESULTS

Individuals with a history of knee injury were 7.4 (95% C.I. 5.9-9.4) times as likely to develop knee OA than were those individuals who did not have a history of knee injury.

CONCLUSION

Acute knee joint injury appears to be a risk factor for the development of knee OA. Prevention strategies for OA should be targeted to those individuals with a history of acute knee injury.

Adverse events, including death, associated with the use of 1,4-butanediol

BACKGROUND

1,4-Butanediol is an industrial solvent that, when ingested, is converted to gamma-hydroxybutyrate, a drug of abuse with depressant effects, primarily on the central nervous system. After reports of toxic effects of gamma-hydroxybutyrate and its resultant regulation by the federal government, 1,4-butanediol and gamma-butyrolactone, another precursor of gamma-hydroxybutyrate and an industrial solvent, began to be marketed as dietary supplements. We investigated reports of toxic effects due to the ingestion of 1,4-butanediol and reviewed the related health risks.

METHODS

From June 1999 through December 1999, we identified cases of toxic effects of 1,4-butanediol involving patients who presented to our emergency departments with a clinical syndrome suggesting toxic effects of gamma-hydroxybutyrate and a history of ingesting 1,4-butanediol and patients discovered through public health officials and family members. We used gas chromatography-mass spectrometry to measure 1,4-butanediol or its metabolite, gamma-hydroxybutyrate, in urine, serum, or blood.

RESULTS

We identified nine episodes of toxic effects in eight patients who had ingested 1,4-butanediol recreationally, to enhance bodybuilding, or to treat depression or insomnia. One patient presented twice with toxic effects and had withdrawal symptoms after her second presentation. Clinical findings and adverse events included vomiting, urinary and fecal incontinence, agitation, combativeness, a labile level of consciousness, respiratory depression, and death. No additional intoxicants were identified in six patients, including the two who died. The doses of 1,4-butanediol ingested ranged from 5.4 to 20 g in the patients who died and ranged from 1 to 14 g in the nonfatal cases.

CONCLUSIONS

The health risks of 1,4-butanediol are similar to those of its counterparts, gamma-hydroxybutyrate and gamma-butyrolactone. These include acute toxic effects, which may be fatal, and addiction and withdrawal.

Mucus production by endometrium of reproductively healthy mares and mares with delayed uterine clearance

The aims of this study were to compare various staining and fixation techniques for endometrial biopsy samples and, thus, to investigate the mucociliary apparatus in endometrium from reproductively healthy mares and mares with delayed uterine clearance. Endometrial samples were collected from the left and right uterine horns of reproductively healthy mares (n=5) and mares with delayed uterine clearance (n=4) during anoestrus, transition, oestrus and dioestrus. Each sample of endometrium was fixed in either Bouin's fixative or formalin, and stained with alcian blue (pH 1.0 or 2.5), periodic acid Schiff (alone and in combination with alcian blue) or mucicarmine. An extracellular mucus blanket was observed more frequently in tissue fixed in Bouin's fixative than in formalin-fixed tissue. Luminal epithelial cells and the extracellular mucus blanket were stained preferentially using alcian blue (pH 2.5). Ciliated cells were observed most readily in biopsy samples fixed with formalin and stained with either alcian blue (pH 2.5) or mucicarmine. Mucus production was increased in fibrotic nests and inflamed endometrial samples. According to image analysis, the amount of intracellular mucus increases during oestrus, but secretions become denser during dioestrus (P < 0.05). In the present study, mucus production in mares with delayed uterine clearance was greater than that of reproductively healthy mares (P < 0.05).

Aqueous phase hexylchloroformate derivatization and solid phase microextraction: determination of benzoylecgonine in urine by gas chromatography-quadrupole ion trap mass spectrometry

A derivatization/solid phase microextraction (SPME) method for the determination of benzoylecgonine in urine was developed. The derivatization is conducted directly in 1 mL of urine while sonicating for 3 min with 12 microL of hexyl chloroformate and 70 microL of a mixture containing acetonitrile:water:hexanol:2-dimethylaminopyridine (5:2:2:1 v/v), yielding benzoylecgonine hexyl ester (BHE) as the product. After the 3 min period, an aliquot of 250 microL is transferred to a vial for SPME. After the desired extraction time the 100 microns polydimethylsiloxane SPME fiber was transferred to the GC-MS for separation and analysis with a quadrupole ion trap mass spectrometer. The hexyl chloroformate derivatization and SPME procedures were optimized for compatibility and sensitivity. The method was found linear for 0.10 to 20.0 micrograms/mL (r2 = 0.999) of benzoylecgonine in urine using benzoylecgonine-d3 as an internal standard (1.5 micrograms/mL). Intra-day precisions were 8.8 and 6.8% RSD for 0.30 microgram/mL and 17 micrograms/mL benzoylecgonine standards in urine (n = 6), respectively. Inter-day precision (n = 3) were < or = 3.3% RSD, indicating good reproducibility. A detection limit of 0.03 microgram/mL (S/N = 3) was achieved, thus making the SPME method a simplified alternative to SPE for GC-MS confirmation after EMIT tests for benzoylecgonine which have a cutoff of 0.30 microgram/mL. Quantitative results by SPME and SPE of two clinical urine specimens known positive for cocaine by EMIT were in excellent agreement. Benzoylecgonine was detected by the derivatization/SPME method in 22 out of 22 other urine specimens known positive for cocaine.

Determination of cannabinoids in water and human saliva by solid-phase microextraction and quadrupole ion trap gas chromatography/mass spectrometry

Solid-phase microextraction (SPME) is applied to the determination of cannabidiol, delta 8-tetrahydrocannabinol (delta 8-THC), delta 9-tetrahydrocannabinol (delta 9-THC), and cannabinol in pure water and human saliva. The inherent extraction behavior of the cannabinoids in pure water is evaluated along with optimization of the method in human saliva. The commercially available poly(dimethylsiloxane) (PDMS) SPME fibers were found to be the best class for the cannabinoid analysis. Partition coefficients were found to be extremely large for all of the cannabinoids (log K > 4.0). Equilibrium times for the 7- and 30-micron PDMS fibers were 50 and 240 min, respectively. A shorter extraction time of 10 min with the 30-micron PDMS fiber may be used for multiple extractions from the same vial, thus conserving the sample necessary for analysis and speeding up the total analysis time. Recoveries for the cannabinoids in saliva, relative to pure water, were dramatically improved by a method developed in our laboratory involving addition of glacial acetic acid to the sample vial prior to performing SPME. Using this method, recoveries relative to SPME in pure water ranged from 21 to 47% depending on the cannabinoid. The linear range for spiked saliva samples was established at 5-500 ng/mL (r2 > 0.994) with precisions between 11 and 20% RSD. The ultimate level of detection by SPME for the cannabinoids in saliva was 1.0 ng/mL, with signal-to-noise values of > or = 12. A saliva sample collected 30 min after marijuana smoking was subject to SPME and traditional liquid-liquid extraction analysis. Internal standard quantitation results for delta 9-THC by both methods yielded comparable results, indicating that the SPME method of analysis is highly accurate and precise. The level of delta 9-THC by SPME was found to be 9.54 ng/mL for the saliva sample.

Pulmonary lesions in experimental ophidian paramyxovirus pneumonia of Aruba Island rattlesnakes, Crotalus unicolor

Histologic and ultrastructural changes were observed in the respiratory portions of lung in five 29-40-month-old Aruba Island rattlesnakes, Crotalus unicolor, that were inoculated with an Aruba Island Rattlesnake virus (AIV) strain of ophidian paramyxovirus (OPMV) isolated from an Aruba Island rattlesnake. Lungs from one non-infected and three mock-infected Aruba Island rattlesnakes were examined also. From 4 to 22 days following intratracheal inoculation, progressive microscopic changes were seen in the lung. Initially, increased numbers of heterophils were observed in the interstitium followed by proliferation and vacuolation of epithelial cells lining faveoli. The changes appeared to progress from cranial to caudal portions of the respiratory lung following inoculation. Beginning at 4 days postinoculation, viral antigen was demonstrated in epithelial cells lining faveoli with an immunofluorescent technique using a rabbit anti-AIV polyclonal antibody. Electron microscopy revealed loss of type I cells, hyperplasia of type II cells, and interstitial infiltrates of heterophils and mononuclear cells. Viral nucleocapsid material was seen within the cytoplasm and mature virus was seen budding from cytoplasmic membranes of infected type I and type II cells from 8 to 19 days after infection. A virus consistent with AIV was isolated from lung tissues of infected rattlesnakes, thus fulfilling Koch's postulates.

Determination of barbiturates by solid-phase microextraction (SPME) and ion trap gas chromatography-mass spectrometry

Solid-phase microextraction (SPME) in conjunction with quadrupole ion trap GC-MS was applied to the determination of a series of barbiturates. A 65 microns Carbowax-divinylbenzene (DVB) SPME fiber was used to successfully extract a series of eight barbiturates from aqueous solution. Absorption kinetics and distribution coefficients for the 65 microns Carbowax-DVB SPME fiber were determined for the compounds. In addition the method was evaluated with respect to linearity, limit of detection, precision, desorption time, and the effect of salt. Limits of detection reached 1 ng/ml for the barbiturates. Linearity was established for the barbiturates over a concentration range of 10-1000 ng/ml, with coefficients of correlation 0.99. Overall, the precision of the method fell between 2.2%-6.5%, depending on the barbiturate. SPME was applied to the identification and quantitation of the barbiturates in a urine matrix. The method was validated by analyzing a reference standard pentobarbital-spiked urine sample. Both standard addition and internal standard with [2H5]-pentobarbital techniques were evaluated, with recoveries found to be 93% and 104%, respectively SPME was then used to rapidly screen a urine specimen tested positive for barbiturates, and butalbital was detected and quantified.

Staining and morphologic features of bone marrow hematopoietic cells in desert tortoises (Gopherus agassizii)

OBJECTIVES

To determine optimal site for collection of bone marrow from desert tortoises, and to characterize cytologic staining and morphologic features of bone marrow hematopoietic cells.

ANIMALS

16 desert tortoises.

PROCEDURE

Bone marrow was obtained at necropsy from the pelvis, proximal portion of the humerus, femur, and thickened portions of the cranial to craniolateral and caudal to caudolateral margins of the carapace and plastron for histologic and cytologic examinations. Cytocentrifuged preparations of marrow cells were evaluated for reactivity to cytochemical stains.

RESULTS

Histologic sections were adequate for evaluating acidophils, acidophil precursors, and erythrocyte precursors. It was difficult to differentiate among monocytes, lymphocytes, thrombocytes, and blast cells, and eosinophils could not be differentiated from heterophils. Basophils were in rare, small clusters of 3 to 12 cells. A few lymphoid follicles were found in the pelvis and long bones. Use of cytochemical staining accomplished differentiation between agranular heterophil precursors and granulated heterophils, and between granulated eosinophils and basophils. Monocytes, azurophils, and monoblasts had similar staining features. Staining of erythrocyte precursors with Sudan black B differentiated them from lymphocytes. Only a few small cells with periodic acid-Schiff-positive cytoplasm were identified as thrombocytes. Lymphocytes did not stain with any of the cytochemical stains.

CONCLUSIONS

For histologic and cytologic evaluation of bone marrow hematopoietic cells, pelvis, proximal portion of the humerus, femur, and thickened portions of the peripheral cranial and caudal regions of the carapace and plastron are suitable sites to collect specimens. There are distinct cytochemical markers for heterophil, monocyte, and erythrocyte precursors, as well as later stage heterophils, eosinophils, basophils, monocytes, and azurophils.

An in vitro preparation of frog nose and brain for the study of odour-evoked oscillatory activity

An in vitro preparation is described that consists of frog brain rostral to the brainstem connected to the nasal epithelium by the olfactory nerves. Field potential and intracellular recordings from various brain structures can be obtained while stimulating the nasal epithelium with air-borne odours for at least 12 h after removal of the brain. Power spectra, amplitude and duration of odour-evoked and spontaneous field potentials in vitro are similar to those obtained from paralyzed, spinal cord pithed frogs. A brief puff of odorant applied to the olfactory epithelium produces a 1-2 s bout of 7-13 Hz oscillations in the field potential recorded from the ipsilateral bulb and various ventral, lateral and medial telencephalic structures. Odour evoked bulbar oscillations are maintained after removal of the telencephalon. Electrical stimulation of the olfactory nerves will not elicit oscillations like those evoked by odour stimulation. High-pressure puffs of non-odorised, moist air, elicit olfactory bulb oscillations similar to those evoked by lower pressure puffs of odorised air. Intracellular recordings from most mitral cells reveal oscillations in membrane potential that are phase-locked to the field potential. The extent to which these phase-locked oscillations produce action potentials varies, apparently as a function of the strength and duration of a long-lasting inhibitory potential that is superimposed upon the 7-13 Hz oscillations. This preparation is well-suited for the study of the cellular basis of oscillatory activity in vertebrate brain, and the function of sensory-evoked oscillatory responses in processing of sensory information.

Characterization of paramyxoviruses isolated from three snakes

Multiple epizootics of pneumonia in captive snakes have been attributed to viruses which have been tentatively placed in the family Paramyxoviridae. Viruses isolated from an ill Neotropical rattlesnake (Crotalus durissus terrificus), from an Aruba Island rattlesnake (Crotalus unicolor), and from a bush viper (Atheris sp.) were propagated in Vero cells and characterized. Viral particles produced in Vero cells were pleomorphic, enveloped, and contained helical nucleocapsids. The viruses were sensitive to ether and to acidic and basic pH. Moreover, they had neuraminidase activity and were able to agglutinate erythrocytes from chicken and a variety of species of mammals. Hemagglutination was inhibited with rabbit antiserum raised against each virus. The buoyant densities of the three isolates ranged from 1.13/cm3 to 1.18/cm3, values consistent with that for an enveloped virus. The nucleic acid in the virion was determined to be RNA by [3H]uridine incorporation. Viral proteins characteristic of paramyxoviruses were immunoprecipitated from cells infected with each of the three isolates using rabbit anti-Neotropical virus serum. The morphologic appearance, physico- and biochemical properties, and cytopathologic effects of these snake viruses were consistent with those of certain members of the family Paramyxoviridae.

Ion-molecule reactions of oxygenated chemical ionization reagents with vincamine

The ion-molecule reactions of ions from acetone, dimethyl ether, 2-methoxyethanol, and vinyl methyl ether with vincamine were investigated. Reactions with dimethyl ether result in [M+13](+) and [M+45](+) products, reactions with 2-methoxyethanol produce [M+13](+) and [M+89](+) ions, and reactions with acetone or vinyl methyl ether ions generate predominantly [M+43](+) ions. Collision-activated dissociation and deuterium labeling experiments allowed speculation about the product structures and mechanisms of dissociation. The methylene substitution process was shown to occur at the hydroxyl oxygen and the phenyl ring of vincamine for dimethyl ether reactions, but the methylene substitution process was not favored at the hydroxyl oxygen for the 2-methoxyethanol reactions, instead favored at the 12 phenyl position. The reaction site is likely different for the 2-methoxyethanol ion due to its capability for secondary hydrogen-bonding interactions. For the [M+45](+) and [M+89](+) ions, evidence suggests that charge-remote fragmentation processes occur from these products. In general, the use of dimethyl ether ions or 2-methoxyethanol ions for ionmolecule reactions prove highly diagnostic for the characterization of vincamine; both molecular weight and structural information are obtained. Limits of detection for vincamine with dimethyl ether chemical ionization via this technique on a benchtop ion trap gas chromatography-tandem mass spectrometer are in the upper parts per trillion range.

The effect on diagnostic quality of using dual isotope imaging for 81Krm ventilation and 99Tcm-MAA perfusion lung scanning

It is the practice in some centres to use dual isotope imaging to reduce imaging times in lung ventilation and perfusion studies with 81Krm gas and 99Tcm-macroaggregated albumin (99Tcm-MAA) by simultaneous acquisition of the two images. The resulting loss of image caused by cross-talk between the two energy windows was investigated using two phantoms, one with cold 99Tcm lesions of varying size and contrast, and the other a uniform field of 81Krm. It was found that, under scatter conditions typical of a patient study, the use of dual isotope acquisition and a krypton generator of 470 MBq or greater resulted in a perceptible loss of image quality with lesions up to 4 cm in diameter being missed. On an older camera system, without modern energy and linearity correction facilities, a lower generator activity of only 120 MBq was sufficient to cause image degradation even under very low scatter conditions. Seventy-five patient studies were performed using both single and dual isotope imaging with generator activities ranging from 80 to 282 MBq. At these low generator activities, the studies did not demonstrate any differences between the images that would result in a different diagnosis. We conclude that the use of dual isotope V/Q scanning reduces the diagnostic value of the perfusion image if the activity of the 81Krm generator is too high, although at generator activities of 300 MBq or less no loss of image quality will occur on modern camera systems.

Physical activity as a risk factor for osteoarthritis of the knee

A case-control study was conducted to evaluate the association between knee osteoarthritis (OA) and physical activity (PA) among a community group aged 40 years and older. Case patients (85 males, 154 females) had radiologically confirmed knee OA with grade 2+ changes, according to Kellgren and Lawrence criteria. Control subjects (85 males, 154 females) had no radiologic evidence of knee OA. A statistically significant positive association between high PA level and knee OA was observed for women, with an age-adjusted odds ratio (OR) of 1.66 and 95% confidence interval (CI) of 1.01 to 2.72. In men no association was observed (OR = 0.95; 95% CI, 0.49 to 1.83). These associations persisted when controlling simultaneously for potential confounders including age, obesity, history of knee injury, and socioeconomic status, indicating that the OA-PA association is limited to women. One possible explanation is that risk factors for knee OA are influenced by hormones.

Characteristics of canine melanomas and comparison of histology and DNA ploidy to their biologic behavior

The biologic behavior of 179 formalin-fixed, paraffin-embedded canine melanomas was correlated with their histologic appearance. In addition, flow cytometric analysis of DNA content was performed on 54 of these tumors. Histologic examination accurately predicted clinical course in 89% of the melanomas with known behavior. Flow cytometry accurately predicted behavior in 93% of tumors with diagnostic histograms and demonstrated malignant features in 100% of metastases from malignant oral tumors; histograms were non-diagnostic for 15% of tumors tested. Histologic examination, flow cytometry, and biologic behavior were in agreement for 93% of the tumors with diagnostic histograms. Interpretive problems were encountered in analyzing heavily pigmented melanomas using this flow cytometry technique.

Production of 2,3-butylene glycol from whey by Klebsiella pneumoniae and Enterobacter aerogenes

Production of 2,3-butylene glycol from whey with Klebsiella pneumoniae and Enterobacter aerogenes was studied. Sterilization of the whey was unnecessary. Acid whey required neutralization, but sweet whey did not. Butylene glycol production was most efficient at 33 degrees C for Klebsiella pneumoniae and at 37 degrees C for Enterobacter aerogenes. Aeration significantly improved yields. Klebsiella pneumoniae produced more butylene glycol than did Enterobacter aerogenes in unsupplemented whey. The addition of 50 mM sodium acetate to whey increased the production of butylene glycol and acetoin by Enterobacter aerogenes; it also increased the production of glycol by Klebsiella pneumoniae, but the increase in this case was offset by a decrease of production of acetoin. Maximal yields of the glycol plus acetoin in whey were obtained in 48 to 64 h, but Enterobacter aerogenes required about 160 h for complete utilization of the lactose. Highest yields were about .3 M butylene glycol plus acetoin, which corresponds to the production of about 10 kg of glycol from 380 liters of whey.

An immunoperoxidase study of senile cerebral amyloidosis with pathogenetic considerations

Samples of human cerebral cortex were obtained from twelve autopsied patients with Alzheimer's disease or "normal" aging. Rabbit or goat anti-human antisera to the following plasma proteins: IgG, F(ab')2, Fc, kappa and lambda light chains, IgM, IgA, fibrinogen, albumin, C3, lysozyme, haptoglobin, macroglobulin, and microglobulin; antibodies to the following intracellular proteins: glial fibrillary acidic (GFA) protein, filamin, actin, non-muscle myosin, tubulin, cholinergic vesicle proteins, and neurofilament (NF) proteins were utilized in the immunoglobulin peroxidase bridge. Amyloid cores of classical or perivascular plaques and dyshoric angiopathy exhibited a strong reaction for intact IgG and for both of its light chains, moderate reactions for lysozyme, fibrinogen, albumin and IgA, and weak reactions for IgM, C3, Fc, F(ab')2, haptoglobin, macroglobulin and microglobulin. Antibodies to all three NF proteins, individually and pooled, stained dyshoric and plaque amyloid, while antibodies to other intracellular proteins did not. The coronae of classical plaques and many primitive plaques stained for GFA, but inconsistently for IgG, both light chains, lysozyme, actin, tubulin, and NF proteins. Affected vessels of three patients with Congophilic angiopathy were reactive for all plasma proteins (especially IgG, fibrinogen, and albumin) and for NF proteins. NF staining in Congophilic blood vessels, although variable, revealed a peripheral or adventitial distribution, whereas plasma proteins tended to be localized in the media of the vessel wall. The distributions of Congo red and NF positivity were often identical. Both NF and Congo red staining was sensitive to oxidation. Isolated NF proteins were Congophilic and capable of displaying apple-green birefringence. A hypothesis concerning the role of NF proteins in senile cerebral amyloid is presented.

Immunocytochemical localization of lysozymes in respiratory and other tissues

Immunostaining paraffin sections of appropriately fixed tissues with an antiserum to human urinary lysozyme as the primary step in an immunoglobulin-peroxidase bridge method has localized lysozyme in previously recognized sites such as Paneth cells, renal tubules, and lymph node macrophages in several species. In addition, lysozyme was demonstrated in the ciliary layer of the trachea, and type II pneumocytes, as well as cells of presumed mucoid nature in laryngotracheal glands. Large stellate cells in follicle centers in the lymph nodes and spleen and in the medulla of the thymus evidenced strong lysozyme reactivity. Granular pneumocytes disclosed immunoreactivity for lysozyme also at the ultrastructural level. Lysoplate assay demonstrated lysozyme in abundance in both the cellular pellet and acellular supernatant of rat alveolar wash fluid and in rat lung after repeated washing of alveoli. Hamster lung differed from the others in failing to immunostain for lysozyme and affording no evidence for content of lysozyme as determined by lysoplate assay. Sites stained with antiserum to human urinary lysozyme failed to stain with antiserum to egg white lysozyme. However, the pyloric glands, Golgi elements in intestinal epithelium, the surface of the colon, and the proximal straight renal tubule of the mouse stained exclusively with the antiserum to hen egg white lysozyme. Many sites staining with antiserum to urinary lysozyme in respiratory, renal, and lymphoid tissue lacked reactivity in control sections exposed to this antiserum after it was absorbed with purified urinary lysozyme. However, mucous acini in submandibular glands, although failing to stain with other control procedures, retained towared the absorbed antiserum, possibly through reacting with an antibody other than that for human urinary lysozyme. A number of cell types containing proteinaceous cytoplasmic granules stained in control sections exposed to normal serum in place of antilysozyme serum in the immunoglobulin-peroxidase bridge procedure and, thus, possessed selective, but nonimmunospecific affinity for immunoglobulin. Cell types that stained with antiserum to hen egg white lysozyme lost affinity for the antiserum after its absorption with egg white lysozyme but retained the affinity after absorption with urinary lysozyme.

Cytochemical differentiation of nucleic acids with a Schiff-methylene blue sequence

A method is described whereby a Feulgen type of hydrolysis of deoxyribonucleic acid is carried out on paraffin sections of routinely fixed tissues by controlled exposure of the sections to Bouin's fluid. Subsequent staining with Schiff reagent followed by methylene blue distinguishes red-to purple-stained deoxyribonucleic acid from blue-stained ribonucleic acid. This Schiff-methylene blue sequence visualizes ribonucleic acid in nucleoli and the chromidial substance of various normal and neoplastic cells and provides an assessment of their protein synthetic activity. The method has proved valuable in demonstrating normal immunocytes and immunoglobulin-forming tumor cells in pathologic specimens.

Ultrastructural staining of thin sections with iron hematoxylin

Verhoeff's iron hematoxylin (VIH) applied to epoxy thin sections provides ultrastructural staining of selected sites including elastic fibers, ribosomes, heterochromatin in nuclei of somatic cells, chromatin clumps in germ cells and the nucleolonema and ovoid body of the nucleolus of primary spermatocytes. Granules in rat parotid acinar cells show several staining patterns not otherwise easily recognized. Mucous droplets or granules of goblet or Paneth cells of the ileum stain. Staining of defined polymers in epoxy thin sections indicates that VIH reacts with polycations and polyanions. Ethanolic hematoxylin alone at pH 1.3 imparts electron opacity to heterochromatin, ribosomes, parotid granules and elastica but yields no staining for light microscopy. A hematoxylin-FeCl3, solution stains mucus of goblet and Paneth cells. The latter staining, which requires FeCl3 in the solution, can be eliminated by saturating the solution with NaCl and, accordingly, depends on ionic binding. Staining of elastic fibers and parotid acinar granules depends on hydrogen bonding, since saturation of the VIH or hematoxylin solution with urea blocks the ultrastructural staining. Urea does not, however, alter the staining of nuclear structures or ribosomes.