Antibodies to Aedes aegypti D7L salivary proteins as a new serological tool to estimate human exposure to Aedes mosquitoes

Introduction

Aedes spp. are the most prolific mosquito vectors in the world. Found on every continent, they can effectively transmit various arboviruses, including the dengue virus which continues to cause outbreaks worldwide and is spreading into previously non-endemic areas. The lack of widely available dengue vaccines accentuates the importance of targeted vector control strategies to reduce the dengue burden. High-throughput sensitive tools to estimate human-mosquito contact and evaluate vector control interventions are lacking. We propose a novel serological tool that allows rapid screening of large human cohorts for exposure to potentially infectious mosquitoes and effective targeting of vector control.

Methods

We tested 563 serum samples from a longitudinal pediatric cohort study previously conducted in Cambodia. Children enrolled in the study were dengue-naïve at baseline and were followed biannually for dengue incidence for two years. We used Western blotting and enzyme-linked immunosorbent assays to identify the most immunogenic Aedes aegypti salivary proteins and measure total anti- Ae. Aegypti IgG.

Results

We found a strong correlation (r s =0.86) between the combined IgG responses against AeD7L1 and AeD7L2 recombinant proteins and those to whole salivary gland homogenate. We observed seasonal fluctuations of AeD7L1+2 IgG responses, corresponding to Aedes spp. abundance in the region, and no cross-reactivity with Culex quinquefasciatus and Anopheles dirus mosquitoes. The baseline median AeD7L1+2 IgG responses for young children were higher in those who developed asymptomatic dengue versus those who developed symptomatic dengue.

Conclusion

The IgG response against AeD7L1+2 recombinant proteins is a highly sensitive and Aedes specific marker of human exposure to Aedes bites that can facilitate standardization of future serosurveys and epidemiological studies by its ability to provide a robust estimation of human-mosquito contact in a high-throughput fashion.

1176. Metagenomic Next-Generation Sequencing of Nasopharyngeal Swabs in Acute Febrile Illness in Cambodia

Background

There is growing recognition of metagenomic next-generation sequencing (mNGS) as a valuable diagnostic tool capable of providing unbiased pathogen detection, but data on performance in low-resource settings remains scant. Here, we use mNGS of nasopharyngeal (NP) swabs taken from subjects in Cambodia to identify potential pathogens causing acute febrile illness.

Methods

Febrile subjects aged 2 months to 65 years were enrolled in a cross-sectional study conducted across 4 tertiary hospitals in Cambodia. NP swabs were collected at hospital presentation. Depending on reported symptom constellations, sera was also taken in a subset of subjects for comparison of mNGS results. RNA was isolated from biosamples, converted to cDNA libraries, and sequenced on a NextSeq2000 (Illumina). Raw sequence reads were stripped for host reads and aligned to NCBI nucleotide and protein databases using a cloud-based bioinformatics platform (CZID).

Results

NP swabs were collected from 97 subjects between April 2020 and June 2021. Subjects were predominantly male (53.6%) and young (median age 3 years [IQR 1-25]). Pathogens were identified in 42 (43.2%) NP swabs; of these, 26 (61.9%) were respiratory viruses including 9 rhinovirus, 7 coronavirus (1 SARS-CoV-2), and 5 respirovirus cases. Co-infection was identified in 3 subjects with coronavirus and respirovirus (N=2) and coronavirus and rhinovirus (N=1). Of subjects with paired sera and NP samples (N=61), 18 (29.5%) had positive NP swabs but negative sera, 7 (11.5%) had negative NP swabs but positive sera, 12 (19.7%) had positive NP swabs and sera, and 24 (39.3%) had negative NP swabs and sera. Pathogen hits correlated in NP swabs and sera in 10 of 12 subjects, including six subjects with chikungunya.

Conclusion

mNGS can be successfully implemented in low-resource settings to identify emerging pathogens and common respiratory pathogens, including co-infecting pathogens, from NP swabs of febrile patients. mNGS may also be able to detect chikungunya from NP swab alone, raising the possibility of non-invasive diagnostics for infections associated with high viremic states.

Disclosures

All Authors: No reported disclosures.

Evaluation of cutaneous immune response in a controlled human in vivo model of mosquito bites

Mosquito-borne viruses are a growing global threat. Initial viral inoculation occurs in the skin via the mosquito 'bite', eliciting immune responses that shape the establishment of infection and pathogenesis. Here we assess the cutaneous innate and adaptive immune responses to controlled Aedes aegypti feedings in humans living in Aedes-endemic areas. In this single-arm, cross-sectional interventional study (trial registration #NCT04350905), we enroll 30 healthy adult participants aged 18 to 45 years of age from Cambodia between October 2020 and January 2021. We perform 3-mm skin biopsies at baseline as well as 30 min, 4 h, and 48 h after a controlled feeding by uninfected Aedes aegypti mosquitos. The primary endpoints are measurement of changes in early and late innate responses in bitten vs unbitten skin by gene expression profiling, immunophenotyping, and cytokine profiling. The results reveal induction of neutrophil degranulation and recruitment of skin-resident dendritic cells and M2 macrophages. As the immune reaction progresses T cell priming and regulatory pathways are upregulated along with a shift to T_h2-driven responses and CD8⁺ T cell activation. Stimulation of participants' bitten skin cells with Aedes aegypti salivary gland extract results in reduced pro-inflammatory cytokine production. These results identify key immune genes, cell types, and pathways in the human response to mosquito bites and can be leveraged to inform and develop novel therapeutics and vector-targeted vaccine candidates to interfere with vector-mediated disease.

CITY-PSO: Prescribing behaviour of French private-practice dermatologists in psoriasis management: An observational, multicentre, cross-sectional study

BACKGROUND

Information regarding the prescribing behaviour of French private-practice dermatologists (PPDs) is scarce.

OBJECTIVES

First, to describe the population of PPDs involved in psoriasis management. Second, to describe the population of adult patients treated for psoriasis and their management.

METHODS

We published a call for participation targeting PPDs; we first asked respondents to complete a form regarding their prescribing behaviour, and then to include consecutive patients consulting for psoriasis during a one-month study period and to collect patient data.

RESULTS

The 94 participating PPDs included 1022 patients of mean age 52.9±17.9 years. The average body mass index was 28, and 25% had vascular comorbidities. Two thirds of patients had chronic psoriasis, for which 45% had consulted at least 5 times. Psoriasis was mostly with plaques (70.8%) and 11.4% of patients had psoriatic arthritis. The average body surface area (BSA) affected was 10.1%. Among the 679 patients without initial systemic treatment, 159 were started on systemic treatment. The main agents initiated were phototherapy (n=63), methotrexate (n=40), acitretin (n=30) and apremilast (n=20). In multivariate analysis, a higher BSA [Odds Ratio (OR) 1.10, 95% Confidence Interval (CI): 1.07-1.13; P<10^-4] and Dermatology Life Quality Index (DLQI) [OR 1.09, 95% CI: 1.03-1.15; P=0.04] were associated with prescription of systemic therapy at the end of the consultation.

CONCLUSION

The main limitation of our study was that participating PPDs were strongly involved in psoriasis management, which accounts for the high proportion of moderate-to-severe psoriasis and prescription of systemic treatments. Such committed PPDs and the development of psoriasis networks are key factors for improving the quality of care provided to psoriasis patients.

Evaluation of the CareStart™ glucose-6-phosphate dehydrogenase (G6PD) rapid diagnostic test in the field settings and assessment of perceived risk from primaquine at the community level in Cambodia

Background

Primaquine is an approved radical cure treatment for Plasmodium vivax malaria but treatment can result in life-threatening hemolysis if given to a glucose-6-phosphate dehydrogenase deficient (G6PDd) patient. There is a need for reliable point-of-care G6PD diagnostic tests.

Objectives

To evaluate the performance of the CareStart™ rapid diagnostic test (RDT) in the hands of healthcare workers (HCWs) and village malaria workers (VMWs) in field settings, and to better understand user perceptions about the risks and benefits of PQ treatment guided by RDT results.

Methods

This study enrolled 105 HCWs and VMWs, herein referred to as trainees, who tested 1,543 healthy adult male volunteers from 84 villages in Cambodia. The trainees were instructed on G6PD screening, primaquine case management, and completed pre and post-training questionnaires. Each trainee tested up to 16 volunteers in the field under observation by the study staff.

Results

Out of 1,542 evaluable G6PD volunteers, 251 (16.28%) had quantitative enzymatic activity less than 30% of an adjusted male median (8.30 U/g Hb). There was no significant difference in test sensitivity in detecting G6PDd between trainees (97.21%), expert study staff in the field (98.01%), and in a laboratory setting (95.62%) (p = 0.229); however, test specificity was different for trainees (96.62%), expert study staff in the field (98.14%), and experts in the laboratory (98.99%) (p < 0.001). Negative predictive values were not statistically different for trainees, expert staff, and laboratory testing: 99.44%, 99.61%, and 99.15%, respectively. Knowledge scores increased significantly post-training, with 98.7% willing to prescribe primaquine for P.vivax malaria, an improvement from 40.6% pre-training (p < 0.001).

Conclusion

This study demonstrated ability of medical staff with different background to accurately use CareStart™ RDT to identify G6PDd in male patients, which may enable safer prescribing of primaquine; however, pharmacovigilance is required to address possible G6PDd misclassifications.

Pituitary apoplexy and rivaroxaban

Pituitary apoplexy (PA), defined by the occurrence of a massive hemorrhagic necrotic rearrangement within a pituitary adenoma, is rare. Its occurrence can be associated with certain risk factors, including anticoagulation. We report the first case of PA with rivaroxaban which is one of the new oral anticoagulants: a 73 year-old patient presenting with severe headache and visual field deterioration. Surgery was performed. Radiotherapy treatment was decided three months after surgery because of tumor residue.

Role of defects in laser-induced modifications of silica coatings and fused silica using picosecond pulses at 1053 nm: II. Scaling laws and the density of precursors

We investigate the role of defects in laser-induced damage of fused silica and of silica coatings produced by e-beam and PIAD processes which are used in damage resistant, multi-layer dielectric, reflective optics. We perform experiments using 1053 nm, 1-60 ps laser pulses with varying beam size, number of shots, and pulse widths in order to understand the characteristics of defects leading to laser-induced damage. This pulse width range spans a transition in mechanisms from intrinsic material ablation for short pulses to defect-dominated damage for longer pulses. We show that for pulse widths as short as 10 ps, laser-induced damage properties of fused silica and silica films are dominated by isolated absorbers. The density of these precursors and their fluence dependence of damage initiation suggest a single photon process for initial energy absorption in these precursors. Higher density precursors that initiate close to the ablation threshold at shorter pulse widths are also observed in fused silica, whose fluence and pulse width scaling suggest a multiphoton initiation process. We also show that these initiated damage sites grow with subsequent laser pulses. We show that scaling laws obtained in more conventional ways depend on the beam size and on the definition of damage for ps pulses. For this reason, coupling scaling laws with the density of precursors are critical to understanding the damage limitations of optics in the ps regime.

The role of defects in laser-induced modifications of silica coatings and fused silica using picosecond pulses at 1053 nm: I. Damage morphology

Laser-induced damage with ps pulse widths straddles the transition from intrinsic, multi-photon ionization and avalanche ionization-based ablation with fs pulses to defect-dominated, thermal-based damage with ns pulses. We investigated the morphology of damage for fused silica and silica coatings between 1 ps and 60 ps at 1053 nm. Using calibrated laser-induced damage experiments, in situ imaging, and high-resolution optical microscopy, atomic force microscopy, and scanning electron microscopy, we show that defects play an important role in laser-induced damage down to 1 ps. Three types of damage are observed: ablation craters, ultra-high density pits, and smooth, circular depressions with central pits. For 10 ps and longer, the smooth, circular depressions limit the damage performance of fused silica and silica coatings. The observed high-density pits and material removal down to 3 ps indicate that variations in surface properties limit the laser-induced damage onset to a greater extent than expected below 60 ps. Below 3 ps, damage craters are smoother although there is still evidence as seen by AFM of inhomogeneous laser-induced damage response very near the damage onset. These results show that modeling the damage onset only as a function of pulse width does not capture the convoluted processes leading to laser induced damage with ps pulses. It is necessary to account for the effects of defects on the processes leading to laser-induced damage. The effects of isolated defects or inhomogeneities are most pronounced above 3 ps but are still discernible and possibly important down to the shortest pulse width investigated here.

[Primary localized cutaneous nodular amyloidosis: A diagnostic and therapeutic challenge]

BACKGROUND

Nodular primary localized cutaneous amyloidosis (PLCA) is a rare subtype of localized cutaneous amyloidosis in which amyloid protein is derived from immunoglobulin light chains. Follow-up for progression to systemic amyloidosis or autoimmune disease is mandatory. No consensus exists regarding treatment.

PATIENTS AND METHODS

We report a case of nodular PLCA in a 49-year-old man, presenting as an asymptomatic nodule of the nose. Skin biopsy revealed diffuse deposition of amyloid associated with plasmocyte proliferation. Monotypic kappa light-chain restriction was observed. Extensive systemic evaluation, including bone marrow biopsy and PET scan, was negative. Protein electrophoresis and immunofixation in serum and urine were normal. The nodule was treated with radiotherapy but there was no response. Mohs micrographic surgery (MMS) was performed with no recurrence at 6 months of follow-up. No systemic progression was observed one year after the initial diagnosis.

DISCUSSION

Since nodular PLCA may have a cutaneous presentation similar to that of primary systemic amyloidosis, evaluation for systemic amyloidosis is necessary. Treatment of amyloidosis is difficult. Radiotherapy appears ineffective in treating this type of primary cutaneous amyloidosis, and surgical treatment, where possible, is a good option, especially with MMS, which allows both controlled excision and minimal margins.

Two clustered cases of confirmed influenza A(H5N1) virus infection, Cambodia, 2011

In February 2011, a mother and her child from Banteay Meanchey Province, Cambodia, were diagnosed, postmortem, with avian influenza A(H5N1) virus infection. A field investigation was conducted by teams from the Cambodian Ministry of Health, the World Health Organization and the Institut Pasteur in Cambodia. Nasopharyngeal, throat and serum specimens collected from 11 household or three neighbour contacts including two suspect cases tested negative by reverse transcriptase-polymerase chain reaction (RT-PCR) for A(H5N1). Follow-up sera from the 11 household contacts also tested negative for A(H5N1) antibodies. Twenty-six HCW who were exposed to the cases without taking adequate personal protective measures self-monitored and none developed symptoms within the two following weeks. An unknown number of passengers travelling with the cases on a minibus while they were symptomatic could not be traced but no clusters of severe respiratory illnesses were detected through the Cambodian surveillance systems in the two weeks after that. The likely cause of the fatal infection in the mother and the child was common-source exposure in Preah Sdach District, Prey Veng Province. Human-to-human transmission of A(H5N1) virus was unlikely but genetic susceptibility is suspected. Clusters of A(H5N1) virus infection should be systematically investigated to rule out any human-to-human transmission.

Cartilage stress-relaxation proceeds slower at higher compressive strains

Articular cartilage is the connective tissue which covers bone surfaces and deforms during in vivo activity. Previous research has investigated flow-dependent cartilage viscoelasticity, but relatively few studies have investigated flow-independent mechanisms. This study investigated polymer dynamics as an explanation for the molecular basis of flow-independent cartilage viscoelasticity. Polymer dynamics predicts that stress-relaxation will proceed more slowly at higher volumetric concentrations of polymer. Stress-relaxation tests were performed on cartilage samples after precompression to different strain levels. Precompression increases the volumetric concentration of cartilage biopolymers, and polymer dynamics predicts an increase in relaxation time constant. Stress-relaxation was slower for greater precompression. There was a significant correlation between the stress-relaxation time constant and cartilage volumetric concentration. Estimates of the flow-dependent timescale suggest that flow-dependent relaxation occurs on a longer timescale than presently observed. These results are consistent with polymer dynamics as a mechanism of cartilage viscoelasticity.

[Strip papular mucinosis associated with systemic sclerosis]

INTRODUCTION

Other than discreet infra-clinical mucinous deposits observed during many inflammatory dermatoses, clinically visible dermal mucinosis can sometimes be associated with collagenosis. It is usually lupus and very rarely scleroderma. In this case, no confusion with papular mucinosis must be made.

CASE REPORT

A 51 year-old woman presented with infiltrated erythematous lesions in strips on the inner sides of the thighs and legs, associated with myalgia, arthralgia and puffy fingers. Mixed connective tissue disease was the initial diagnosis. The clinical picture was rapidly completed by sclerodactylia, telangiectasia, a Raynaud's syndrome and esophageal involvement leading to the diagnosis of CREST-type systemic scleroderma. The biopsy of the erythematous strip lesions revealed a dermal mucinosis. Treatment with hydroxychloroquine led to the regression of the mucinous lesions and the stabilization of the scleroderma, which, four years later, had not developed further.

DISCUSSION

Dermal mucinosis can accompany lupus erythematosus, in rare cases dermatomyositis and, in exceptional cases, scleroderma. The clinical presentation varies with large infiltrated plaques, reticulated or papulo-nodular lesions. Conversely, strip lesions such as those observed in our patient have never been reported till now. The association of a localized dermal mucinosis and a scleroderma must not lead to the erroneous diagnosis of papular mucinosis of clearly differing prognosis. The occurrence of a mucinosis during collagenosis might be related to enhanced synthesis of mucin by the fibroblasts mediated by the inflammatory cytokines, increased in this context.

Malaria dipsticks beneficial for IMCI in Cambodia

OBJECTIVES

The Integrated Management of Childhood Illness (IMCI) approach and new clinical treatment guidelines to control malaria among children less than 5 years old were introduced recently in Cambodia. This study was conducted to finalize the malaria part of the national IMCI fever chart.

METHODS

A total of 323 sick children 2-59 months old were studied at rural health centres in northern Cambodia from February to April 2000. Cases with fever (by axillary temperature or history) or anaemia (by palmar pallor) were tested with dipsticks for Plasmodium falciparum and Plasmodium vivax in high and low malaria risk areas and, if positive, treated with anti-malarials.

RESULTS

The draft IMCI chart identified children with malaria safely and effectively (sensitivity 14 of 15, approximately 93% and specificity 292 of 308, approximately 95%). The study confirmed the potential of malaria dipsticks as a part of IMCI case management.

CONCLUSION

The Cambodian Ministry of Health will use the studied malaria chart during the Early Implementation Phase of IMCI. Dipsticks able to detect P. falciparum and P. vivax with high sensitivity and acceptable cost will be needed for this purpose. To promote the rational use of dipsticks, the National Centre for Malaria Control, Parasitology and Entomology (Centre National de Malaridogie, Parasitologie et Entomologie, CNM) should list all known malaria risk areas in the country and prepare detailed local maps guiding case management especially in transitional zones.

Risk of cancer among women with AIDS in New York City

To evaluate the risk of cancer among women with AIDS in New York City (NYC), we compared the cancer experience of AIDS-infected women in NYC with that of the general population of women in NYC by matching the population-based New York State Cancer Registry with the New York City AIDS Registry. A probabilistic algorithm was used to match names, birth dates, and, where available, Social Security numbers between 15,146 women with AIDS and 232,902 women with cancer. Standardized incidence ratios (SIR) were calculated as the ratio of observed to expected cancer cases in the population of NYC women matched for age, race, and calendar period of cancer diagnosis. Period-specific relative risks (RR) of cancer prevalence prior to AIDS, and incidence at or after AIDS were calculated to determine which cancers increased in proximity to an AIDS diagnosis, a surrogate marker of increasing immunodeficiency. Analysis was limited to women between the ages of 15 to 69 who were diagnosed with AIDS between 1981 and 1994. Among 15,146 women diagnosed with AIDS, we found 1,194 matches with the Cancer Registry. For cancers included in the 1993 AIDS case definition, the SIR was 178.49 for Kaposi's sarcoma, 48.97 for non-Hodgkin's lymphoma, and 9.20 for invasive cervical cancer. The overall SIR for all non-AIDS-defining cancers was 2.20. Among non-AIDS-defining cancers, elevated SIRs were found for cancers of the lung (7.95), esophagus (7.69), multiple myeloma (7.37), oral cavity and pharynx (6.55), Hodgkin's disease (5.65), leukemias (4.52), and rectal/anal cancers (3.23). Statistically significant increases in period-specific risks were found for all non-AIDS-defining cancers combined, but not for individual cancers. Dual screening by two registries and unknown behavioral factors complicate the ascertainment of cancer risk. Our results show significantly elevated risks for several non-AIDS-defining cancers; these results are consistent with other studies of cancers among persons with AIDS. Extension of the time period of analysis is required to test for the effects of new anti-viral treatments and their association with cancer development among HIV-infected women.

Primary cutaneous Nocardia asteroides infection after heart transplantation

Skin diseases due to Nocardia are rare in Europe and usually occur as the secondary localization of a pulmonary lesion in immunocompromised patients. We describe a cutaneous pyoderma and cold abscess due to Nocardia asteroides infection in a cardiac transplant recipient. An insect bite represents the wound of this soil saprophyte belonging to the actinomycetes. Treatment by sulfone and ampicillin-clavulanic acid allowed the regression of lesions without extracutaneous dissemination.

Surgical treatment of an endovascular metastatic melanoma of the superior vena cava

A 42-year-old woman, who had undergone excision of a melanoma of her right forearm 3 years before (Breslow's index 4.4 mm), was admitted to hospital for the evaluation of an superior vena cava syndrome. The thoracic CT scan and the phlebography showed obstruction of the superior vena cava by an endovascular tumor. Abdominal, pelvis and cranial CT scans did not reveal any other metastatic localization. Surgery with extracorporeal circulation was performed. The mass was resected and histopathologic examination confirmed the endovascular metastatic melanoma. There was no heart metastasis. The patient was then given a polychemotherapy. She was still alive after 18 months of follow-up after the initial metastasis. To our knowledge, no similar case has previously been reported and surgical treatment, as for isolated heart metastatic melanoma, may be considered for vascular metastasis, as in our case.

[Sweet syndrome associated with Crohn disease]

The association of Sweet's syndrome and Crohn's disease is rare. We report a new case of such association. A 45 year-old woman developed a diarrhea, fever, and skin lesions consistent with a presumptive diagnosis of Sweet's syndrome. Crohn's disease was also diagnosed. Oral prednisone, associated with mesalazine, effected improvement of both cutaneous lesions and bowel disease. The ten cases of the literature and ours show that Sweet's syndrome may occur during an acute phase of Crohn's disease. Most of the time, Crohn's disease has already been diagnosed. However, this was not so with our patient, wherein lies the originality of our case. A general corticotherapy is the preferred course of treatment.

Modeling road-cycling performance

This paper presents a complete set of equations for a "first principles" mathematical model of road-cycling performance, including corrections for the effect of winds, tire pressure and wheel radius, altitude, relative humidity, rotational kinetic energy, drafting, and changed drag. The relevant physiological, biophysical, and environmental variables were measured in 41 experienced cyclists completing a 26-km road time trial. The correlation between actual and predicted times was 0.89 (P < or = 0.0001), with a mean difference of 0.74 min (1.73% of mean performance time) and a mean absolute difference of 1.65 min (3.87%). Multiple simulations were performed where model inputs were randomly varied using a normal distribution about the measured values with a SD equivalent to the estimated day-to-day variability or technical error of measurement in each of the inputs. This analysis yielded 95% confidence limits for the predicted times. The model suggests that the main physiological factors contributing to road-cycling performance are maximal O2 consumption, fractional utilization of maximal O2 consumption, mechanical efficiency, and projected frontal area. The model is then applied to some practical problems in road cycling: the effect of drafting, the advantage of using smaller front wheels, the effects of added mass, the importance of rotational kinetic energy, the effect of changes in drag due to changes in bicycle configuration, the normalization of performances under different conditions, and the limits of human performance.

Inactivation of hepatic acetyl-CoA carboxylase by catecholamine and its agonists through the alpha-adrenergic receptors

The effects of adrenergic agonists on acetyl-CoA carboxylase and fatty acid synthesis were studied in isolated rat hepatocytes from mature rats (300 to 350 g). Norepinephrine and phenylephrine inactivate acetyl-CoA carboxylase activity and inhibit fatty acid synthesis. The effects of both norepinephrine and phenylephrine were blocked by the alpha-adrenergic receptor blockers, phentolamine and phenoxybenzamine, and unaffected by the beta-receptor blocker propranolol. This inactivation was not mimicked by the beta-agonist isoproterenol. The measurable increase in cyclic AMP levels caused by norepinephrine and phenylephrine was abolished by the alpha-antagonist phentolamine and diminished by the beta-antagonist propranolol. Calcium depletion potentiated the increase in cyclic AMP levels by phenylephrine but abolished the phenylephrine inactivation of the carboxylase. The inactivation of acetyl-CoA carboxylase by phenylephrine was correlated with an increase in the incorporation of [32P]phosphate into the enzyme. Thus, catecholamines and their agonists promote phosphorylation and inactivation of acetyl-CoA carboxylase through the alpha-adrenergic receptor, and the inactivation requires calcium.