Assessing attentional task-related electroencephalogram signal variations by using mobile electroencephalogram technology: An experimental study

BACKGROUND

A better understanding of the network responses of cortical activities during rest and cognitive tasks is necessary. Therefore, in this study, we aimed to evaluate cerebral activities during attentional tasks by using mobile electroencephalography, identifying the types of attentional components and brain waves.

METHODS

In this experimental study, we enrolled 12 healthy young adults. The attentional tasks comprised parts A and B of the Trail-Making Test (TMT). Nineteen electroencephalography electrodes were placed over various brain regions. The Wilcoxon signed-rank test was used to examine the differences in power levels between the rest and TMT conditions.

RESULTS

During TMT part A, the electroencephalography power level of the delta waves was significantly higher in the right frontal, left central, left occipital, left inferior frontal, right mid-temporal, right posterior temporal, and middle parietal areas (P < .05) than those during the resting state; that of the alpha waves was significantly lower in the left posterior temporal area (P = .006); and that of the high gamma waves was significantly lower in the left parietal (P = .05) and left occipital (P = .002) areas. During TMT part B, the electroencephalography power level of the beta waves was significantly higher in the right frontal area (P = .041) than that during the resting state, and that of the low gamma waves was significantly higher in the left frontal pole, right frontal, and right inferior frontal areas (P < .05). During the focused attentional task, the power level of the delta waves increased and that of the alpha waves decreased, and during the alternating attentional task, those of both the beta and gamma waves increased. The delta waves were related to the whole brain, the alpha and high gamma waves to the left posterior lobe, and the beta and low gamma waves to both frontal lobes.

CONCLUSION

These findings contribute to the basic knowledge necessary to develop new attentional assessment methods for clinical situations.

An effective salivation-facilitating method for COVID-19 testing: An experimental study

BACKGROUND

Simple tools, such as antigen test kits, are readily available for determining coronavirus disease 2019 infection at hospitals and homes. However, it is challenging for elderly people who are prone to dry mouth and other diseases. The main objective of this study was to investigate whether the presence or consumption of a plum pickle can facilitate salivation during coronavirus disease 2019 testing.

METHOD

Twenty healthy adult women participated in the study. The participants were allocated to 2 groups: presentation and non-presentation (n = 10; with and without presentation of a plum pickle, respectively), and eating and non-eating (n = 10; with and without consumption of plum pickle, respectively). We recorded the number of saliva swallows in 1 minute under each condition, using a swallowing test device, which attached film sensors to the hyoid bone and thyroid cartilage.

RESULTS

There was a significant difference in the number of swallows between the non-presentation and presentation groups (P < .01, r = 0.89, Z = -2.82) as well as between the non-eating and eating groups (P < .01, r = 0.85, Z = -2.68).

CONCLUSIONS

The strength of 3 factors, namely: direct stimulation with citric acid, saliva buffer capacity, and motor learning, may have affected the results. Our study suggests that saliva collection using the plum pickle is an effective complementary method for facilitating salivation. This technique may be useful in avoiding the risk associated with citric acid intake and for efficient specimen collection during coronavirus disease 2019 testing. In the future, we need to verify this method in elderly participants in a clinical setting.

Diagnostic model for preschool workers' unwillingness to continue working: Developed using machine-learning techniques

The turnover of kindergarten teachers has drastically increased in the past 10 years. Reducing the turnover rates among preschool workers has become an important issue worldwide. Parents have avoided enrolling children in preschools due to insufficient care, which affects their ability to work. Therefore, this study developed a diagnostic model to understand preschool workers' unwillingness to continue working. A total of 1002 full-time preschool workers were divided into 2 groups. Predictors were drawn from general questionnaires, including those for mental health. We compared 3 algorithms: the least absolute shrinkage and selection operator, eXtreme Gradient Boosting, and logistic regression. Additionally, the SHapley Additive exPlanation was used to visualize the relationship between years of work experience and intention to continue working. The logistic regression model was adopted as the diagnostic model, and the predictors were "not living with children," "human relation problems with boss," "high risk of mental distress," and "work experience." The developed risk score and the optimal cutoff value were 14 points. By using the diagnostic model to determine workers' unwillingness to continue working, supervisors can intervene with workers who are experiencing difficulties at work and can help resolve their problems.

The Association between Party Horn Use and Respiratory Function in Patients with Dementia: An Experimental Study

Background and Objectives: Respiratory diseases account for 55.5% and 33.1% of all mortality rates in patients with Alzheimer’s disease and vascular dementia, respectively. However, the widespread use of spirometers is often difficult due to challenges in performing the procedure. Therefore, the use of spirometers is usually unfeasible in patients with dementia and hinders the provision of preventive measures for aspiration pneumonia. The party horn is a common toy in many countries and can potentially be used as a novel tool. This study was conducted to analyze the usefulness of the party horn as an assessment tool for respiratory function, and to detect eating-related behavioral problems in patients with dementia. Materials and Methods: A total of 62 inpatient participants with dementia (34 males, 28 females; age, mean ± SD, 80.4 ± 7.59 years) were included in the study. The respiratory functions of patients were assessed using a party horn and a spirometer. Assessment items pertaining to cognitive function, mental and behavioral disorders, eating-related behavioral problems, and the required dietary modifications were evaluated to compare between patient groups stratified by respiratory function. Results: Significant differences between groups were noted in length of hospital stay, cognitive functions, mental and behavioral disorders, eating-related behavioral problems, and dietary modifications. Forced expiratory volume in 1 s, peak expiratory flow, and eating-related behavioral problems were significantly associated with the party-horn-integrated value (p < 0.05). Conclusions: Party-horn-based evaluation can facilitate the screening and evaluation of older dementia patients for eating-related behavioral problems and aspiration risk.

Why Do They Leave? The Counterplans to Continue Working among Preschool Workers in Japan: A Cross-Sectional Survey

Three institutions predominantly care for preschool children in Japan: kindergartens, authorized childcare institutions, and nursery centers. Recently, the turnover rates of preschool workers in these institutions have been high, and Japan has been facing a shortage of kindergarten teachers. The study aimed to provide concrete counterplans to reduce preschool workers' turnover rate. To determine the causes of turnover, we conducted a cross-sectional survey. We recruited preschool workers from several kindergartens, authorized childcare institutions, and nursery centers in Japan to fill out a survey regarding counterplans for employment. Of the 1002 surveys, 551 (541 women; 10 men) complete surveys were received (response rate: 55%). A total of 295 participants answered that they were unwilling to continue working for longer than five years and completed the questionnaires. The Jiro Kawakita method was used to categorize and analyze the four sections of the counterplan questionnaires. The results showed that the main reasons for high turnover were overtime work, low salary, and difficult human relations. To solve these issues, the counterplan ideas such as workshop ideas and conditions conducive to continuing working longer were related to human relations, work conditions, and mental health.

Measuring attentiveness toward oral care needs: a comparative study of Indonesian care workers in Japan and Indonesia

BACKGROUND

Japan has opened its labor market to care workers from Indonesia under the Japan-Indonesia Economic Partnership Agreement (EPA). However, few studies have examined the types of care skills transferred between countries. We therefore analyzed Indonesian care workers employed in Japan and Indonesia to identify discrepancies in their attentiveness toward oral care in older adults.

METHODS

A checklist comprising 42 items of universal oral care assessment was developed prior to the study and distributed via the Internet to 418 Indonesian EPA care workers in Japan and via a paper survey to 213 Indonesian care workers in Indonesia. The Mann-Whitney U test was used to compare the distribution of scores for each checklist item for each group.

RESULTS

The respondents were 110 Japan-based EPA care workers (response rate: 26.3%) and 213 Indonesia-based care workers (response rate: 99.1%). Japan-based care workers were significantly more likely to perform environmental observations of their older adult patients (p < 0.001) and to check items on the oral care checklist during feeding (p < 0.001) and post-meal (p = 0.001), while Indonesia-based care workers were more likely to check the overall condition of patients before meals (p = 0.021).

CONCLUSIONS

Discrepancies in checking oral care between the two groups were attributed to the differences in laws and regulations governing the care environments. Indonesian care workers employed in Japan have the advantage of learning to employ a more systematic approach in caring for older adults, in accordance with Japan's Long-Term Care Act. This approach could contribute toward lowering the risk of aspiration pneumonia in Indonesia. A training program designed for returning migrant workers to transfer newly developed oral care skills will thus be essential for Indonesia to diminish the negative impacts of its aging population.

Using party horns to test respiratory function in patients with dementia

This study assessed the utility of party horns for quick, simple respiratory function testing in 66 inpatients with dementia to maintain safe eating activity. Relationships of forced vital capacity (FVC) to Mini-Mental State Examination (MMSE) score and complete extension when blowing 40- and 80-cm party horns were examined. The FVC differed significantly by both MMSE score (P = .000) and party horn score (P = .000). Significant differences in FVC were found between groups categorized by MMSE score and in groups categorized by the ability to extend both party horns. Multiple regression analyses performed on possible FVC indicators identified a significant correlation for the party horn examination (regression coefficient: .562). Breathing is always coordinated with swallowing. Party horns seem highly effective as a simple tool for testing respiratory function in patients with early-stage dementia, and the ability to offer breathing rehabilitation for patients in need is likely to result in safer eating activity.

Association of sarcopenia with swallowing problems, related to nutrition and activities of daily living of elderly individuals

[Purpose] The purpose of the current study was to clarify problems associated with swallowing, related to nutrition and activities of daily living (ADL), in elderly individuals with sarcopenia. [Subjects and Methods] Seventy-seven subjects were assigned to a sarcopenia or a non-sarcopenia group according to a definition used by the European Working Group on Sarcopenia in Older People. Analyses were conducted including and excluding subjects with a central nervous system disorders in order to focus on the influence of sarcopenia. The swallowing ability, ADL, and nutrition levels were compared between the 2 groups. [Results] Swallowing function as well as ADL and nutrition levels were significantly lower in the sarcopenia group than in the non-sarcopenia group. [Conclusion] It is important to include dimensions of swallowing, nutrition, and ADL in the assessment and treatment of swallowing problems in elderly individuals with sarcopenia.

Clinical Study of Respiratory Function and Difference in Pneumonia History between Alzheimer's Disease and Vascular Dementia Groups

[Purpose] This study compared respiratory function and differences in pneumonia history between Alzheimer’s disease and vascular dementia groups. [Subjects] Fifty-eight inpatients in the dementia treatment ward in a psychiatric facility were enrolled. [Methods] Patients underwent respiratory function testing twice using an 80-cm party horn. The Mini-Mental State Examination was also performed and motor functions were evaluated. Patient characteristics were obtained from medical records. [Results] Significant differences were noted between Alzheimer’s disease and vascular dementia groups in the ability to blow the party horn to full length, pneumonia history, and presence of impaired mobility. [Conclusion] Party horn evaluation may be useful for determining the risk of pneumonia in patients with dementia.

Relationship between Swallowing Dysfunction and Decreased Respiratory Function in Dementia Patients

[Purpose] This study aimed to clarify whether respiratory function differed between dementia patients using and not using thickening fluids and texture-modifying foods for swallowing dysfunction management. [Subjects] Sixty-five inpatients in the dementia treatment ward in a psychiatric facility were enrolled. [Methods] The patients underwent respiratory function testing twice with an 80-cm party horn. Moreover, information about the patients' characteristics and use of thickening fluids and texture-modifying foods was obtained from their medical records. [Results] There was a significant difference in being able to blow the party horn to its full length between patients using and not using thickening liquids. [Conclusion] This result suggests that decreased respiratory function may reflect swallowing dysfunction in dementia patients.

Influence of Age and Bolus Size on Swallowing Function: Basic Data and Assessment Method for Care and Preventive Rehabilitation

Objective numerical data on swallowing function are needed to aid in eating and swallowing intervention and preventive rehabilitation. Using noninvasive methods, the influences of age and differences in size of water bolus on laryngeal activity and respiratory activity were examined in healthy young and older women. Swallowing function was influenced by age and bolus size. Influence of bolus size was recognized only in duration of laryngeal movement in younger women, with no apparent influence in older women. Results for older women were thought to be related to declines in swallowing function with the physiological aging of respiratory and swallowing muscles. In the future, noninvasive methods need to be developed for evaluating function and therapeutic effects against swallowing function impairment and to provide objective numerical data for health insurers.

[A case of percutaneous and transpapillary placements of expandable metallic stents in a patient with cholangiocarcinoma at the hilum of the liver]

A 76-year-old woman was admitted with obstructive jaundice. US and MR cholangiopancreatography (MRCP) revealed an inoperative cholangiocarcinoma, 3 cm in diameter at the hilum of the liver, the obstruction of the hepatic duct bifurcation and the separation of bilateral hepatic bile ducts. Percutaneous transhepatic biliary drainage (PTBD) was performed from bilateral hepatic bile ducts. The right PTBD tube was spontaneously extubated. We could not succeed in performing internal biliary drainage across the hilar malignant stricture from a left hepatic bile duct, because of bad angulation. Transpapillary insertion into the common bile duct (CBD) was extremely difficult due to the collapse of the CBD. Endoscopic sphincterotomy (EST) after precutting method was performed. Although we performed the ballooned dilatation of malignant stricture and the insertion of a self-expandable metallic stent (EMS) into a right hepatic bile duct transpapillary. After dilatation of the hilar malignant stricture by the initial EMS, we inserted a guidewire into the CBD through the wire mesh of a stent from the left PTBD tube. We could insert the second EMS from a left hepatic bile duct to the CBD transhepatically, using a dilator and a dilating balloon. Finally, we performed the ballooned dilatation from bilateral hepatic bile ducts to the CBD transpapillary. She was discharged after bilateral internal biliary drainages, successfully.

[An extremely elderly patient with choledocholithiasis and many complications]

It was very difficult to treat a 90-year-old woman for choledocholithiasis with acute obstructive suppurative cholangitis, gallbladder perforation, and a pool of bile in the right perirenal spase. Extracorporeal shockwave lithotripsy (ESWL) was performed after emergency percutaneous transhepatic biliary drainage (PTBD), but we could not perform lithotripsy successfully because of large and hard stones. Although Endoscopic sphincterotomy (EST) was performed using an ultratome by rendezvous method. Lithotripsy was finally successful, after three times endoscopic mechanical lithotripsy (EML) and procedure using an endotriptor for basket impaction. It is very important in advanced aged patients that endoscopic treatment should be performed step by step.

Successful treatment of cytomegalovirus colitis with ganciclovir in a patient with adult T cell leukemia lymphoma: case report

An 84-year-old patient with adult T cell leukemia lymphoma (ATLL) developed diarrhea on day 5 of chemotherapy and was diagnosed with cytomegalovirus (CMV) colitis. Sigmoidoscopy revealed multiple superficial erosions surrounded by a flare. Computed tomography (CT) and ultrasonogram of the abdomen revealed marked thickening of the colonic mucosa. There were 186 CMV antigen-positive leukocytes per 31,000 white blood cells (WBC). A colonic biopsy specimen showed typical CMV nuclear inclusions. Immunohistological study of the specimen was positive for CMV antigen. Administration of ganciclovir (DHPG) 500 mg/day for 14 days improved the diarrhea and other symptoms. On day 30 of the chemotherapy, the patient developed diarrhea again but was diagnosed with pseudomembranous colitis instead of CMV colitis. At that time, CMV antigenemia and a histologic study for CMV were negative. The stool was positive for Clostridium difficile toxin antigen. ATLL patients are believed to be immunocompromised hosts and often develop opportunistic infections such as CMV infection. Most suffer from CMV pneumonia at the end of their course of therapy. Few gastrointestinal (GI) CMV infections are seen in ATLL patients and details of CMV colitis have never been reported. When an ATLL patient develops diarrhea that barely responds to conventional therapy, CMV colitis and pseudomembranous colitis should be listed in the differential diagnosis.

[An elderly case of post-bulbar Dieulafoy's ulcer]

The case is a 79-year-old man who came to our hospital with melena as chief complaint. Emergency endoscopy showed spurting bleeding from a small ulcer. We diagnosed as Post-Bulbar Dieulafoy's ulcer and performed hemostatic procedure with hemostatic clips. The forth endoscopy (7 days after admission) showed fresh clot and oozing bleeding after the third hemostatic clipping. Although we performed hemostatic procedure with the injection therapy of hypertonic saline epinephrine solution (HSE). The effective hemostatic procedure is discussed with reference to some related literature.

[Surgical treatment of secondary chronic colonic pseudo-obstruction]

A 74-year-old woman was admitted to the hospital because of constipation and marked abdominal distension. She had become to be bedridden after cerebral infarction 10 years previously, and was tabescent due to vomiting. A left hemicolectomy and colostomy were performed because conservative therapy seemed to be ineffective. The postoperative course was good and her nutritional status improved.

[A case of endocrine cell carcinoma in the duodenal bulb]

A 73-year-old man was admitted to our hospital due to weight loss and melena. Roentgenograms and endoscopy showed a Borrmann type 2 tumor occupying the entire duodenal bulb. Histological findings of the lesion (H-E stain) showed poorly differentiated adenocarcinoma. Almost the entire specimen showed positive staining granules for Grimelius stain. Ultrastructurally, remarkable endocrine granules covered a layer of the limited membrane (membrane-bound granule) in the tumor cell. We diagnosed endocrine cell carcinoma. Since it was difficult to operate due to age and invasion to the fundus of the gall-bladder and the pancreatic head, we treated this case by chemotherapy.

[A case of Lemmel's syndrome caused by a large diverticular enterolith at the peripapillary portion of the duodenum]

A 93-year-old woman admitted because of epigastralgia. Cholelithiasis, obstructive jaundice, acute suppurative cholangitis and acute pancreatitis were diagnosed on blood chemistry and ultrasonography on admission. We performed emergency PTCD. A calculus 4 cm in diameter was detected at the papilla of Vater and marked dilatation of the common bile duct and pancreatic duct. ESWL was performed because of her age and because endoscopical operation seemed to be difficult. After lithotripsy, PTC and endoscopy demonstrated a diverticulum at the peripapillary portion of the duodenum. Based on analysis of PTC result before and after ESWL, we diagnosed this case as Lemmel's syndrome (obstructive jaundice, acute suppurative cholangitis and acute pancreatitis) caused by a large diverticular enterolith at the peripapillary portion of the duodenum. ESWL treatment of aged patient with an enterolith is safe.

[A case of pancreatic pseudocyst with intracystic hemorrhage and repeated gastrointestinal bleeding]

The case is a 83-year-old woman who came to our hospital with melena and epigastralgia as chief complaints, presenting pre-shock state with high serum amylase value. ERP revealed diffuse dilatation of pancreatic duct and cyst of the accessory pancreatic duct. Endoscopy showed hemorrhage of the accessory papilla. A diagnosis of chronic pancreatitis and hemosuccus pancreaticus was made. Because of the patient's advanced age, conservative treatment (total parenchymal nutrition, transfusion, hemostatics, etc.) were prescribed. The patient succumbed due to heart failure 15 months later. This case of gastrointestinal bleeding from a pancreatic pseudocyst due to neighboring arterial rupture is discussed with reference to some related literature.

[A case of early duodenal cancer resected by endoscopic polypectomy in the elderly]

Early duodenal cancer has been detected with increasing frequency of endoscopy and the advent of an aging society. Aged patients, however, are often inoperable because of complications due to various underlying diseases. The authors report a case of early duodenal cancer curatively operated by endoscopic polypectomy and refer to related cases in the literature.

[Three cases of acquired megacolon in the elderly]

As the number of the elderly in society increase, cases of abnormal bowel habit in the aged have also increased. This report describes 3 cases of acquired megacolon in the elderly. Case 1, a 71-year-old female, complained of constipation and developed megacolon after an attack of cerebral infarction. Case 2, a 82-year-old male, developed megacolon while receiving psychoactive medication. Case 3, a 69-year-old male who complained of constipation for a long time and rapidly developed megacolon was diagnosed as idiopathic megacolon.

[Upper gastrointestinal bleeding in the elderly]

Due to increasing number of the elderly, cases of hematemesis and melena in the aged have been increasing. The authors evaluated 69 such cases over 60 years old in whom emergency endoscopy of the upper digestive tract was carried out because of hematemesis and melena. Twenty cases are diagnosed as gastric ulcer (29%), 12 cases as esophageal ulcer and esophageal erosion (17.4%), 9 as duodenal ulcer (13.0%), 7 as gastric cancer (10.1%), 6 as Mallory-Weiss syndrome (8.7%), 6 as esophageal and gastric varices (8.7%), 4 as acute hemorrhagic gastritis (5.8%), 3 as Dieulafoy's ulcer (4.3%), and one case each of chronic pancreatitis (hemosuccus pancreaticus) and hemorrhage due to gastric angiodysplasia (1.4%). Of these cases, blood transfusion was performed in 46 cases (66.7%), and shock occurred in 27 cases (39.1%). The endoscopical hemostatic procedure was effective for detection of underlying diseases in the aged. Surgery was often impossible because of the rapid deterioration of the systemic condition due to the hemorrhage of the digestive tract.

[Efficacy and safety of percutaneous endoscopic gastrostomy in the elderly]

Percutaneous endoscopic gastrostomy (PEG) was performed in 32 patients with nasogastric feeding (NGF) or total parenteral nutrition (TPN), who were unable to swallow. Our cases of PEG included 10 with dementia, 8 with cerebral infarction, 8 with cerebral bleeding, 3 with gastric cancer, and others. TPN was performed after PEG for a short time. Because of the combination of TPN and PEG, there was no mortality or major complication related to the procedure. Minor complications included subcutaneous abscess and TPN catheter fever. PEG can be safely and rapidly performed. Furthermore, painless life, better cosmetic features and physical condition can be obtained with this procedure. The majority of the patients are able to return home after PEG. PEG can improve the quality of life of the patients who cannot swallow but have an intact gut.

Studies on lipoprotein and adrenal steroidogenesis: II. Utilization of low density lipoprotein- and high density lipoprotein-cholesterol for steroid production in functioning human adrenocortical adenoma cells in culture

We examined the utilization of human low density lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol for steroid production in primary monolayer culture cells from adenomas of primary aldosteronism and Cushing's syndrome and an adrenal of nodular hyperplasia of Cushing's syndrome. We compared the data obtained with findings in the case of cultured normal human adrenocortical cells. In the presence of 10(-7) M adrenocorticotropin (ACTH), the addition of either LDL or HDL to the culture medium at a cholesterol concentration of 100 micrograms/ml led to a significant increase in the daily secretion rates of cortisol, dehydroepiandrosterone sulfate (DHEA-S) and aldosterone in the adenoma and nodular hyperplasia cells, as in the normal cells. Although LDL greatly increased the secretion of steroid hormones, no significant difference in steroid secretion following the treatments with LDL and HDL were observed in these cultured cells. The contribution of endogenous cholesterol to steroid production was also high, thereby indicating that the neoplastic transformation did not have untoward effects. Cells from adenomas of primary aldosteronism secreted not only aldosterone, but also cortisol and DHEA-S. The daily secretion rates of these steroids were markedly increased when ACTH was added to the medium. With prolonged exposure to ACTH, however, the rate of aldosterone secretion showed a gradual decrease with the incubation time. This decrease might be due to the impaired conversion of corticosterone to 18-hydroxycorticosterone. In case of adenomas in patients with Cushing's syndrome, the secretion of steroid hormones varied in quantity and quality, depending on the type of plasma cortisol response to the rapid ACTH test in vivo, thereby suggesting that the adrenocortical adenoma of Cushing's syndrome might be divided into two subtypes. These results indicate that human functioning adrenocortical adenoma cells utilize plasma lipoproteins as a source of cholesterol for steroidogenesis during the prolonged stimulation of steroid secretion.

Studies on lipoprotein and adrenal steroidogenesis: I. Roles of low density lipoprotein- and high density lipoprotein-cholesterol in steroid production in cultured human adrenocortical cells

The roles of human low density lipoprotein (LDL)- cholesterol and high density lipoprotein (HDL)- cholesterol on adrenal steroidogenesis were investigated using cultured human adult and fetal adrenocortical cells and the findings were then compared to those obtained with bovine adrenocortical cells. The secretion of cortisol in both human and bovine adrenocortical cells was dose-dependently increased by the administration of LDL- or HDL-cholesterol in the presence of adrenocorticotropin (ACTH). LDL-cholesterol was utilized to a greater extent than HDL-cholesterol in both human and bovine adrenal steroidogenesis in the presence of ACTH. Exogenous lipoprotein-derived cholesterol was less utilized in human adrenal steroidogenesis than in bovine adrenal steroidogenesis, compared to the endogenous cholesterol. An increase in the secretion of cortisol and dehydroepi androsterone sulfate (DHEA-S) continued for the 5-day culture period, in the presence of lipoprotein cholesterol and ACTH in both human adult and fetal adrenocortical cells. The secretion of aldosterone increased on the first day of the culture period, then gradually decreased for the 5-day culture period in human adult adrenocortical cells, but not in human fetal adrenocortical cells in the presence of lipoprotein cholesterol and ACTH. These findings demonstrate that exogenous cholesterol utilized in the biosynthesis of steroids is mainly from LDL-cholesterol in both human adult and fetal adrenals and bovine adrenal and the proportion of cholesterol synthesized de novo is significantly larger in the human adult adrenal than in the bovine adrenal.