Evaluating adherence to future COVID-19 vaccination among elderly population in Israel

Background

On March 2020, COVID-19 was declared a global pandemic. It was perceived as an elderly issue in face of the high morbidity and mortality rates among people over 60 years old. Instructions regarding protective and preventative conduct were issued by the Israeli ministry of health, with emphasis concerning the elderly population. This study aimed at examining the adherence for future Covid-19 vaccine and its predicting factors among the elderly population in Israel.

Methods

A cross-sectional online survey was conducted in April 2020 among 1,797 Israeli respondents, aged 60 and above, via social media. The questionnaire assessed intentions to being vaccinated against the COVID-19 virus, attitudes and subjective norms regarding the disease and instructions issued by the ministry of health, adhering to these instructions, perception of threat, trust in the healthcare system, negative emotions and social support.

Results

Levels of willingness to future vaccination were extremely high (92%). Multiple logistic regression analysis found gender, level of religiosity, socio-economic status, perception of threat, social support, trust in the healthcare system, negative emotions and subjective norms regarding social distancing, as predictors of probability for future adherence to the vaccine.

Conclusions

The study findings point to future intention, in a time when an atmosphere of uncertainty regarding COVID-19 and its consequences is prevalent around the world. The adherence predictors are in concurrence with elements of the Health Belief Model and the Theory of Reasoned Action. Identifying the factors that predict future willingness to be vaccinated, may assist in developing ways to promote vaccination adherence against COVID-19, as well as against other illnesses.

Key messages

The results emphasize the importance of creating a supportive environment and shaping health-promoting attitudes among the elderly, as well as balanced and reliable threat communication of epidemics.

Actual vaccination would depend on factors such as the pandemic severity at that time.

Family caregiving in an aging society: Key policy questions

An aging population, attended by an increase in chronic diseases and disability, together with decrements in health among the elderly, require considerable health care resources being expended on long-term care needs in the home environment at the community level. Increase in life expectancy, and more substantially, the disproportionate increment within the very oldest age groups and in the number of elderly whose activities are limited by some sort of physical or cognitive disability have significantly increased family care needs. Such demographic shift and socioeconomic changes throughout the developed world are making elderly care an increasingly important public policy issue. Particularly, one of the principal foci of policy makers should be supporting and nurturing family care. This paper focuses on the case of Israel. Like many industrialized countries, Israel faces the challenge of caring for a growing number of vulnerable older people while advancing adequate policies to support both elderly and their informal caregivers. Currently, the demands for family caregivers has increased drastically, and, studies predict that the personal, social, and economic costs of caregiving, which have risen dramatically over the last three decades, will only continue to increase. This paper focuses on the extent to which current legislation supports primary informal caregivers in Israel. A review of the legislation and benefits has indicated that the aid supplied is limited mainly because their application is relevant only in extreme cases where the elderly need constant supervision or care in institutions. Their contribution to most elderly and their families is only partial. The rights afforded to the informal caregivers are relatively few, are limited and are all concentrated in the domain of occupational support, and this also in a restricted manner.

Key message

Family caregiving in an aging society: Key policy questions.

Anatomic variations of the paranasal sinuses in the general pediatric population

BACKGROUND

The prevalence of sinuses' anatomic variations in the healthy pediatric population has not been studied. The study describes the prevalence of known anatomic variations with regard to gender and age in this population.

METHODS

A single academic institute observational cohort study. A total of 200 head CT scans were reviewed, subdivided into five equal age subgroups (0-4.99; 5-7.99; 8-10.99; 11-13.99; 14-17 years), with an equal male to female ratio. Different subgroups were randomly assigned to two senior residents (100 CTs each). A senior rhinologist and radiologist were randomly selected to review 100 CTs each. Consensus was reached after a joint review. Each CT was evaluated for the presence of sinuses and the following variations: deviated septum, frontoethmoidal, infraorbital, posterior-ethmoid cells (Kuhn, Haller, and Onodi cells, respectively) and concha bullosa. Definitions were made according to the European Position on Rhinosinusitis 2012.

RESULTS

Gender did not affect sinus development or anatomical variations. The frontal and sphenoid sinuses were significantly less developed in the 0-4.99 years group. The point prevalence of concha bullosa and deviated septum significantly increased with age. The point prevalence of Haller cells demonstrated borderline significance among age groups, with children 0-4.99 demonstrating the lowest point prevalence. A significant association was found between the existence of Haller cells to Kuhn and Onodi cells.

CONCLUSIONS

Anatomical variations should be expected in the pediatric population. Familiarity with their point prevalence and associations may assist pediatric endoscopic sinus surgery planning.

Novel SBF1 splice-site null mutation broadens the clinical spectrum of Charcot-Marie-Tooth type 4B3 disease

Four siblings of consanguineous Bedouin kindred presented at infancy with an autosomal recessive syndrome of congenital microcephaly, facial dysmorphism, strabismus, developmental delay and ataxia with positive pyramidal signs. Toward the end of their first decade, they developed areflexia, multiple cranial neuropathies and severe polyneuropathy with progressive muscle weakness, affecting proximal and distal extremities. Physical assessment exhibited kyphoscoliosis, bilateral syndactyly and distal muscle wasting with drop-foot and pes cavus. Magnetic resonance imaging (MRI) showed profound cerebellar atrophy with highly unique findings at the pontine and mesencephalic levels, previously described as "fork and bracket" signs. Genome-wide linkage analysis identified a single ~1.5 Mbp disease-associated locus on chromosome 22q13.33. Whole exome sequencing identified a single novel homozygous deleterious splice-site mutation within this locus in SET binding factor 1 (SBF1). SBF1 missense mutations were shown to underlie Charcot-Marie-Tooth (CMT) type 4B3 disease, a rare autosomal recessive subtype of CMT4. The novel SBF1 null mutation highlights distinct severe phenotypic manifestations, broadening the clinical spectrum of SBF1-related neuropathies: cerebellar and pyramidal signs evident in the first months of life with peripheral polyneuropathy emerging only toward the end of the first decade, together with unique MRI findings.

Intravenous opioid drug abuse as an independent risk factor for supraglottic squamous cell carcinoma-A case-control study

OBJECTIVES

Intravenous opioid drug abuse (IVDA) was previously correlated with laryngeal cancer. However, discrimination of this correlation by anatomical subsites has not yet been described. In this study, we aim to further establish the association between IVDA and laryngeal squamous cell carcinoma (SCC) and to indicate the laryngeal subsites that are predisposed for this correlation.

DESIGN

A retrospective matched case-control study.

SETTING AND PARTICIPANTS

Patients diagnosed with supraglottic SCC (SG-SCC) between 1996 and 2016 treated in a tertiary academic referral centre were enrolled to the case group. The control group comprised of matched patients diagnosed with glottis SCC (G-SCC). Matching was based on gender, age and socio-economic rank.

MAIN OUTCOME MEASURES

Variables studies as risk factors included the following: smoking, alcohol consumption, history of IVDA and infectious diseases. The variables were tested for association with the 2 groups and with each other.

RESULTS

Forty-eight patients with SG-SCC were matched with 48 patients with G-SCC. IVDA rates significantly increased among patients with SG-SCC. Of the SG-SCC group, 18.8% had a positive history for IVDA compared with 2.1% of the G-SCC (P = .008). A history of IVDA was found to be a risk factor for SG-SCC, independent of smoking, excessive alcohol and socio-economic status. The odds ratio for patients with an IVDA history to have SG-SCC relatively to G-SCC was 10.846 (95% CI: 1.3-89.4).

CONCLUSIONS

Intravenous opioid drug abuse represents an independent risk factor for SG-SCC. The pathogenesis should be investigated not just as a risk factor, as opioids are commonly used for pain management in oncologic patients.

Surgeon-performed thyroid ultrasound-proving utility and credibility in selecting patients for fine needle aspiration according to the American thyroid association guidelines. A retrospective study of 500 patients

DESIGN

Case series with chart review.

SETTING

Single academic centre.

PARTICIPANTS

The data of all patients who underwent surgeon-performed ultrasound (SUS) between 7/2009 and 9/2012 were retrospectively reviewed.

MAIN OUTCOME MEASURES

A correlation between sonographic features and a non-benign cytology\malignant pathology.

RESULTS

Four hundred ninety-eight nodules were included. Solid texture, irregular margins, hypo-echogenicity and intranodular vascularity were significantly associated with malignancy when benign to non-benign cytology was compared, and when compared to malignant pathology. Lack of suspicious features was significantly associated with benign lesions, with a negative predictive value of 94%. Except for taller than wider shape, malignancy odds ratio was significantly higher for known suspicious features, reaching 4.81 for irregular borders (CI 2.42-9.55, P < .001).

CONCLUSIONS

SUS has proven to be a reliable and consistent tool to assess the thyroid nodule risk stratification. Surgeons should recognise the potential of this tool and its implementation.

The effect of Ramadan fast on the incidence of renal colic emergency department visits

BACKGROUND

Renal colic (RC) is one of the most common reasons for emergency department (ED) visits. Although RC is associated with high ambient temperature and with physiological changes that occur during fast, the literature on between Ramadan and RC incidence is scarce.

AIM

To investigate the association of ED visits with RC during Ramadan fast.

METHODS

We obtained health data of patients visited the ED of a large tertiary centre during the years 2004-15, with a primary diagnosis of RC. To estimate the association of RC and Ramadan, we utilized bi-weekly RC incidence Poisson models adjusted for ambient temperature and seasonality in two ethnic groups residing in the region: Muslims and Jews.

RESULTS

We identified 10 435 unique patients with 18 163 ED visits with primary diagnosis of RC. Although Muslims represent 18.5% of the population in the region, approximately 25% of the ED visits with RC attributed to this group. There was a positive and significant association of temperature and ED visits within all subgroups after adjusting for seasons. Positive association with Ramadan was observed during the first 2 weeks of fast within Muslims (R.R 1.27, 95% C.I 1.03-1.50) but not within Jewish community (R.R 1.061, 95% C.I 0.855-1.238).

CONCLUSION

Our study demonstrates a significant and positive association between RC and Ramadan, while controlling to ambient temperature. In view of these findings, different prevention strategies should be investigated.

X-ray fluorescence-based differentiation of neck tissues in a bovine model: implications for potential intraoperative use

This study explores the possibility of using X-ray fluorescence (XRF)-based trace-element analysis for differentiation of various bovine neck tissues. It is motivated by the requirement for an intra-operative in-vivo method for identifying parathyroid glands, particularly beneficial in surgery in the central neck-compartment. Using a dedicated X-ray spectral analysis, we examined ex-vivo XRF spectra from various histologically verified fresh neck tissues from cow, which was chosen as the animal model; these tissues included fat, muscle, thyroid, parathyroid, lymph nodes, thymus and salivary gland. The data for six trace elements K, Fe, Zn, Br, Rb and I, provided the basis for tissue identification by using multi-parameter analysis of the recorded XRF spectra. It is shown that the combination of XRF signals from these elements is sufficient for a reliable tissue differentiation. The average total abundance of these trace elements was evaluated in each tissue type, including parathyroid and salivary gland for the first time. It is shown that some tissues can unequivocally be identified on the basis of the abundance of a single element, for example, iodine and zinc for the identification of thyroid gland and muscle, respectively.

Increased number of offspring in first degree relatives of psychotic individuals: a partial explanation for the persistence of psychotic illnesses

OBJECTIVE

As patients with psychotic illness have fewer offspring than controls, the persistence of psychotic illness is puzzling. We hypothesized that unaffected first-degree relatives of patients have more offspring than controls.

METHOD

Probands were 4904, individuals with non-affective psychotic disorders identified from a hospitalization registry. Unaffected first degree relatives and matched controls were identified from the Israeli Population Registry. The number of offspring of unaffected parents, biological siblings and controls was ascertained.

RESULTS

Unaffected parents of psychotic patients had more offspring/person than controls; 4.5 +/- 2.7 vs. 3.4 +/- 2.2, P = 0.000. Unaffected parents from familial psychosis families (more than one affected family member) had 1.83 more offspring than controls; unaffected parents from non-familial psychosis families had 0.97 more offspring than controls (both P < 0.001).

CONCLUSION

These findings might imply that genes which increase susceptibility for schizophrenia may be associated with increased number of offspring, perhaps supplying a partial explanation for the persistence of psychosis.

Self-report of family functioning and risk for psychotic disorders in male adolescents with behavioural disturbances

OBJECTIVE

Previous studies indicate that a poor family environment might affect vulnerability for the later manifestation of psychotic illness. The current study aims to examine family functioning prior to the onset of psychosis.

METHOD

Subjects were 42,948, 17-year old males with behavioural disturbances who were asked about the functioning of their family by the Israeli Draft Board. Data on later psychiatric hospitalizations were obtained from a National Psychiatric Hospitalization Registry.

RESULTS

Poorer self-reported family functioning was associated with greater risk for later hospitalization for psychosis [adjusted hazard ratio (HR) = 1.16, 95% CI = 1.05-1.27], with a trend in the same direction for schizophrenia (adjusted HR = 1.1, 95% CI = 0.98-1.24).

CONCLUSION

In male adolescents with behavioural disturbances, perceived poorer family functioning is associated with increased risk for non-affective psychotic disorders and schizophrenia. These data do not enable us to determine if perceived familial dysfunction increases vulnerability for psychosis, if premorbid behavioural abnormalities disrupt family life, or neither.

Moxifloxacin enhances antiproliferative and apoptotic effects of etoposide but inhibits its proinflammatory effects in THP-1 and Jurkat cells

Etoposide (VP-16) is a topoisomerase II (topo II) inhibitor chemotherapeutic agent. Studies indicate that VP-16 enhances proinflammatory cytokines secretion from tumour cells, including IL-8, a chemokine associated with proangiogenic effects. Fluoroquinolones inhibit topo II activity in eukaryotic cells by a mechanism different from that of VP-16. The fluoroquinolone moxifloxacin (MXF) has pronounced anti-inflammatory effects in vitro and in vivo. We studied the effects of MXF and VP-16 on purified human topo II activity and further analysed their combined activity on proliferation, apoptosis and caspase-3 activity in THP-1 and Jurkat cells. Moxifloxacin alone slightly inhibited the activity of human topo II; however, in combination with VP-16 it led to a 73% reduction in enzyme activity. VP-16 inhibited cell proliferation in a time and dose-dependent manner. The addition of moxifloxacin for 72 h to low-dose VP-16 doubled its cytotoxic effect in THP-1 and Jurkat cells (1.8- and 2.6-fold decrease in cell proliferation, respectively) (P<0.004). Moxifloxacin given alone did not induce apoptosis but enhanced VP-16-induced apoptosis in THP-1 and Jurkat cells (1.8- and two-fold increase in annexin V positive cells and caspase-3 activity, respectively) (P<0.04). VP-16 induced the release of IL-8 in a time and dose-dependent manner from THP-1 cells. Moxifloxacin completely blocked the enhanced release of IL-8 induced by 0.5 and 1 μg ml⁻¹ VP-16, and decreased IL-8 release from cells incubated for 72 h with 3 μg ml⁻¹ VP-16 (P<0.001). VP-16 enhanced the release of IL-1β and TNF-α from THP-1 cells, whereas the addition of MXF prevented the enhanced cytokine secretion (P<0.001). We conclude that MXF significantly enhances VP-16 cytotoxicity in tumour-derived cells while preventing VP-16-induced proinflammatory cytokine release. This unique combination may have clinical benefits and cytotoxic drug ‘sparing effect’ and should be further studied in vivo.

Immunomodulatory effects of moxifloxacin in comparison to ciprofloxacin and G-CSF in a murine model of cyclophosphamide-induced leukopenia

We analyzed the effect of the two quinolones moxifloxacin and ciprofloxacin on the repopulation of hematopoietic organs and on the production of cytokines by various organs of cyclophosphamide (CP)-induced leukopenic mice. The effect was compared to that of G-CSF. Cyclophosphamide injection induced a severe leukopenia, with nadir at day 4 post-injection. All the quinolone and G-CSF-treated animals showed WBC>500/microL at the nadir, compared to 50% of saline-treated mice. Cyclophosphamide induced a marked decrease in the number of myeloid progenitors (CFU-C) in bone marrow (BM) and spleen. Quinolone or G-CSF treatment resulted in a 1.4-4.3-fold increase in CFU-C numbers in the BM; no enhancement was observed in the spleen. Treatment with CP resulted in enhanced colony-stimulating activity (CSA) in bone shaft and spleen and decreased activity in bladder and lung. Treatment of CP-injected mice with quinolones significantly enhanced CSA in the bone shaft, spleen, lung and bladder on different days. In normal mice the highest levels of GM-CSF and IL-6 were observed in lung-conditioned medium (compared to bone shaft, spleen and bladder). Injection of CP resulted in a 22.5- and 93-fold decrease in GM-CSF and IL-6 levels, respectively, in lung-conditioned medium, while treatment with quinolones resulted in 2-4-fold increase in GM-CSF with no effect on IL-6 production. G-CSF treatment had no enhancing effect on GM-CSF nor on IL-6 production. We conclude that moxifloxacin and ciprofloxacin administered to CP-injected mice revert some of the immune suppressive effects of cyclophosphamide.

Screening markers for chronic atrophic gastritis in Chiapas, Mexico

Intestinal-type gastric adenocarcinomas usually are preceded by chronic atrophic gastritis. Studies of gastric cancer prevention often rely on identification of this condition. In a clinical trial, we sought to determine the best serological screening method for chronic atrophic gastritis and compared our findings to the published literature. Test characteristics of potential screening tests (antibodies to Helicobacter pyloni or CagA, elevated gastrin, low pepsinogen, increased age) alone or in combination were examined among consecutive subjects enrolled in a study of H. pylori and preneoplastic gastric lesions in Chiapas, Mexico; 70% had chronic atrophic gastritis. English-language articles concerning screening for chronic atrophic gastritis were also reviewed. Sensitivity for chronic atrophic gastritis was highest for antibodies to H. pylori (92%) or CagA, or gastrin levels >25 ng/l (both 83%). Specificity, however, was low for these tests (18, 41, and 22%, respectively). Pepsinogen levels were highly specific but insensitive markers of chronic atrophic gastritis (for pepsinogen I <25 microg/l, sensitivity was 6% and specificity was 100%; for pepsinogen I:pepsinogen II ratio <2.5, sensitivity was 14% and specificity was 96%). Combinations of markers did not improve test characteristics. Screening test characteristics from the literature varied widely and did not consistently identify a good screening strategy. In this study, CagA antibodies alone had the best combination of test characteristics for chronic atrophic gastritis screening. However, no screening test was both highly sensitive and highly specific for chronic atrophic gastritis.

Gastric atrophy and extent of intestinal metaplasia in a cohort of Helicobacter pylori-infected patients

Atrophy and intestinal metaplasia (IM) are preneoplastic gastric lesions associated with Helicobacter pylori infection. Atrophy and IM are usually found together; however, the association between increasing degrees of severity of both atrophy and IM has not been evaluated completely. Two pathologists graded atrophy and IM using the visual analog scale of the Sydney classification in gastric biopsies from 368 H pylori-infected patients. Extent of IM also included determining the number of specimens affected. We then correlated the degree of atrophy with the degree and number of specimens affected with IM by calculating relative risks (RR) and 95% confidence intervals (95% CI). The mean number of biopsies examined from each patient was 6.5. Atrophy and IM were found more frequently in the antrum (85% and 75% of biopsies, respectively). One hundred thirty-eight patients had a combination of atrophy and IM, 48 had IM only, and 89 had atrophy only. Fifty-three subjects had mild atrophy and IM (RR = 1.57; 95% CI 1.2-2.1), 69 had moderate atrophy and IM (RR = 1.86; 95% CI 1.9-2.4), and 16 had marked atrophy and IM (RR = 2.47; 95% CI 1.8-3.3). The median number of biopsy specimens with IM increased from 0 in subjects with no atrophy to 3 in subjects with severe atrophy. The degree of IM correlated with the degree of atrophy; the median degree was 0.6 in subjects with no atrophy and increased to 2.32 in those with severe atrophy. Our data suggest that higher degrees of IM in an individual specimen and increasing number of specimens with IM are associated with moderate or severe degrees of atrophy.

Improved survival in severe acquired aplastic anemia of childhood

Multi-agent immunosuppressive therapy has produced improved survival for severe acquired aplastic anemia in children. Recently, some investigators have suggested that immunosuppressive therapy may replace bone marrow transplantation as first-line therapy for this disorder. To assess its validity, we compared the outcomes of bone marrow transplantation vs immunosuppressive therapy in one institution from 1987 to 1997. We studied 46 consecutive patients less than 18 years of age who presented between January 1987 and April 1997. Inherited marrow failure syndromes and myelodysplastic syndromes were excluded. Patients received immunosuppressive therapy vs bone marrow transplantation based on availability of HLA-matched donors. The main outcome measures were survival, complete marrow and hematological remission, or partial remission but achieving independence from transfusional support. Twenty patients received multi-agent immunosuppressive therapy (cyclosporine, antithymocyte globulin and methylprednisolone); 11 attained complete remission and three partial remission for a transfusion-independent survival of 70%. Six patients died of infectious and hemorrhagic complications. Twenty-six patients were transplanted and 24 (93%) achieved complete remission; one achieved a PR, 25 remain transfusion independent with a median follow-up of 5.9 years or 70 months. One patient developed AML 34 months after successful transplant and one patient died due to graft failure and complications of transplant. There has been a striking improvement in survival for pediatric patients treated with multi-agent immunosuppression in the last decade. However, transplantation results have also improved and this remains the definitive first-line therapy for severe acquired aplastic anemia in this age group.

Management of congenital laryngeal malformations

Congenital malformations of the larynx are relatively rare but may be life-threatening. The most common causes include laryngomalacia, vocal cord paralysis, and subglottic stenosis. The last 20 years has seen major advances in the field of surgical correction of such anomalies also serving to reduce the number of tracheotomies in children and the inherent dangers they pose. Success rates for the most popular surgical procedures have been favorable. These include supraglottoplasty for cases of severe laryngomalacia, in which relief of respiratory symptoms has been shown to occur in excess of 80% of cases. Complication rate is low, although postoperative death has been reported. Failure usually occurs in patients with concomitant airway abnormalities including pharyngomalacia. Vocal cord lateralization for vocal cord paralysis with airway compromise is achieved by means of arytenoidopexy or arytenoidectomy, using the lateral approach. Arytenoidectomy also can be performed using laryngofissure or endoscopic laser excision. Subglottic stenosis is the 3rd most common congenital anomaly. Anterior or multiple cricoid splitting with cartilage graft interpositioning is usually performed. The success rates for these procedures has been shown to be approximately 90%.

Interobserver variability in application of the revised Sydney classification for gastritis

The Sydney classification for gastritis provides guidelines for histological grading of gastric biopsies. In an ongoing study of gastric preneoplastic lesions in Chiapas, Mexico, 7 biopsies from 150 patients (4 from the antrum and 3 from the body) were obtained during endoscopy and studied histologically. The first 74 endoscopy specimens were read independently by 2 general surgical pathologists. We assessed diagnostic concordance using kappa statistics. The 2 pathologists then jointly reviewed biopsies about which they had disagreed to reach a final diagnosis. A second group of 76 endoscopies was subsequently evaluated independently by the 2 pathologists, and concordance was again assessed. In the first group of biopsies, we found low concordance rates (Heliobacter pylori 0.59, acute inflammation 0.22, intestinal metaplasia 0.60, and atrophy 0.04). In the second group, of independently reviewed cases, there was better concordance (H pylori 0.77, acute inflammation 0.50, intestinal metaplasia 0.70, and atrophy 0.64). We presumed that use of the Sydney classification would result in minimal interpretational differences achieving ideal kappas greater than 0.80. Because pathology results are based on subjective interpretation of this classification, complete diagnostic agreement is practically impossible. Concordance by general surgical pathologists after joint review of cases was similar to that obtained by gastrointestinal pathologists.

Ascorbic acid inhibits apoptosis induced by X irradiation in HL60 myeloid leukemia cells

Exposure of cells to ionizing radiation can cause apoptosis. Since antioxidants have been shown to protect against radiation-induced apoptosis, in this study we have evaluated the putative protective effect of ascorbate against radiation-induced apoptosis as well as the production of peroxides in the cells. HL60 cells transport the oxidized form of ascorbic acid, dehydroascorbic acid (DHA), and accumulate reduced ascorbate. Exposure of the cells to 5-40 Gy X radiation resulted in induction of apoptosis. Preincubation of the cells with DHA reduced the level of apoptosis after exposure to 5-20 Gy. Exposure of the cells to 5 or 20 Gy X radiation did not affect the intracellular concentration of peroxides, while phorbol myristate acetate (PMA), which is known to induce production of H(2)O(2) in cells (and served as a control), resulted in an increase in peroxides and a decrease in intracellular ascorbate. Irradiation of the cells with 1-3 Gy resulted in up-regulation of expression of BCL2 without affecting the level of apoptosis. At higher doses of radiation, enhanced BCL2 expression did not prevent radiation-induced apoptosis. Loading of the cells with ascorbate prior to their exposure to 1-3 Gy X radiation did not affect the enhanced BCL2 expression observed in the irradiated cells. At higher doses of radiation, ascorbate decreased apoptosis and restored the level of BCL2 in the cells. Exposure of the cells to 3-20 Gy X radiation enhanced the cell surface expression of TNFRSF6 (formerly known as Fas/APO-1) antigen and enhanced anti-TNFRSF6 antibody-induced apoptosis of the cells. Ascorbate loading did not affect expression of TNFRSF6 and did not overcome the anti-TNFRSF6 antibody-induced apoptosis. In conclusion, our data demonstrate that exposure of HL60 cells to radiation enhanced BCL2 and TNFRSF6 expression. Ascorbate did not affect BCL2 or TNFRSF6 expression. We therefore conclude that it protects HL60 cells against radiation-induced apoptosis, although the mechanisms of protection must still be elucidated.

Alteration of actin organization by jaspamide inhibits ruffling, but not phagocytosis or oxidative burst, in HL-60 cells and human monocytes

Jaspamide, a naturally occurring cyclic peptide isolated from the marine sponge Hemiastrella minor, has fungicidal and growth-inhibiting activities. Exposure of promyelocytic HL-60 cells and human monocytes to jaspamide induces a dramatic reorganization of actin from a typical fibrous network to focal aggregates. HL-60 cells exposed to 5 x 10(-8) mol/L or 10(-7) mol/L jaspamide exhibited a reduced proliferation rate. In addition, 10(-7) mol/L jaspamide induced maturation of HL-60 cells as indicated by the appearance of a lobulated nucleus in 55% +/- 5% of the cells and immunophenotypic maturation of the leukemia cells (upregulation of CD16 and CD14 B antigens). Further characterization has shown that F-actin is aggregated both in HL-60 cells and in human monocytes exposed to 10(-7) mol/L jaspamide. Well-spread cultured human monocytes contracted and adopted round shapes after treatment with jaspamide. Moreover, a dose-dependent increase in both total actin and de novo synthesized portions of the soluble actin was observed in jaspamide-treated HL-60 cells. Jaspamide treatment inhibits ruffling and intracellular movement in HL-60 cells and monocytes, but does not affect phagocytic activity or respiratory burst activity. The consequential effects of jaspamide-induced actin reorganization on ruffling, versus its negligible effect on phagocytosis and oxidative burst, may shed light on molecular mechanisms of actin involvement in these processes. Jaspamide disrupts the actin cytoskeleton of normal and malignant mammalian cells with no significant effect on phagocytic activity and may, therefore, be considered as a novel therapeutic agent.

Dermoid cyst of the eustachian tube

We report a case of dermoid cyst of the Eustachian tube in a 2 1/2 -year-old-girl with CT and MRI imaging. This is the 12th described case of such a pathology. Most of the reviewed previous 11 cases affected females on the left side. The surgical approach and the contribution of CT and MRI are discussed.

Prediction of the survival of patients with advanced ovarian cancer according to a risk model based on a scoring system

PURPOSE OF INVESTIGATION

The aim of the study was to devise a scoring system based on significantly prognostic parameters which might predict the survival time for each individual patient.

METHODS

The study group included 40 patients with stage III or IV invasive ovarian cancer, operated on between 1987 and 1994. Different preoperative and intraoperative parameters were examined and their impact on survival was assessed using the Kaplan-Meier method. Survival rates were compared by the log rank test. The parameters, which have been found to be significant prognostic factors, were incorporated into the final risk model, based on a scoring system. The scores were given according to the cut-off point of each prognostic parameter. A correlation coefficient was calculated from the survival curve, representing the combined scores of individual patients versus their survival.

RESULTS

From all studied parameters, only gravidity, the stage of ovarian cancer and the preoperative levels of LDH and CA-125 were demonstrated to have a significant impact on survival. On the basis of these four parameters a scoring system was devised. The scores were given considering the cut-off level of each parameter: gravidity < or = 2 versus > 2; stage of the cancer - IIIA, IIIB and stage IIIC versus stage IV; LDH level < or = 240 versus > 240 U/L; CA-125 < or = 100 versus > 100 U/ml. The average of the combined scores representing the four parameters was the final risk factor, which was plotted against the survival of each individual patient. A correlation coefficient of -0.99 was found.

CONCLUSIONS

Our data suggest that the survival of each individual patient with advanced ovarian cancer could be predicted quite accurately considering our risk model based on a scoring system which incorporates four preoperative and intraoperative parameters. This scoring system needs to be validated by larger prospective trials.

Rat osteoclast precursors in vivo express a vitronectin receptor and a chloride-bicarbonate exchanger

In vivo osteoclast precursors, which are mononuclear, were previously found to express TRAP (tartrate-resistant acid phosphatase) and CTR (calcitonin receptor), like multinucleated osteoclasts. In vitro, they were found to express, in addition, VNR (vitronectin receptor) and CBE (chloride-bicarbonate exchanger). In order to ascertain that osteoclast precursors in vivo express VNR and CBE like their in vitro counterparts, we used immunohistochemistry to localize these molecules in developing long bones of neonatal rats. Frozen sections of metatarsals and phalanges of 1-2 day-old rats were stained for TRAP and mineralization using histochemistry or were reacted with polyclonal antibodies specific for either the beta3 chain of the VNR or synthetic sequences of the CBE. Both mature, multinucleated osteoclasts within the forming marrow cavity of metatarsals (as shown previously) and mononuclear osteoclast precursors located outside the bony collar of the phalangeal calcified rudiment (as shown here for the first time) expressed both TRAP, VNR and CBE. These findings suggest that mononuclear osteoclast precursors express many of the phenotypical markers of multinucleated osteoclasts prior to their fusion and multinucleation which may allow them to resorb bone, as suggested by in vitro observations of pit formation by preosteoclasts cultured on resorbable substances.

Clinical update on type II first branchial cleft cysts

OBJECTIVE

To describe clinical and radiological signs of type II first branchial cleft cyst in order to facilitate diagnosis.

METHOD

Report of three cases of first branchial cleft cyst type II (one of them in association with ipsilateral agenesis of the parotid gland) and review of the literature.

RESULTS

Two clinical signs are described: the location of the sinus opening in the neck, which is situated in a triangle limited by the external auditory canal above, the mental region anteriorly, and the hyoid bone inferiorly, and the presence in some cases of a myringeal web that runs from the floor of the external auditory canal to the umbo. In addition, imaging with computed tomography and magnetic resonance of the parotid area may be helpful in confirming the diagnosis.

Ethanol injection to parathyroid tissue: indications and limitations

Hyperparathyroidism is a potentially life-threatening disease, caused primarily by parathyroid adenoma. Surgical excision of the tumor, with consequent return of calcium levels to the normal range, is considered the treatment of choice. Within the last few years, several reports have described the destruction of parathyroid tissue using ultrasonically guided injection of 96% ethanol into pathologic parathyroid glands, resulting in successful regulation of both primary and secondary hyperparathyroidism. The procedure was reported as an alternative to operative treatment for patients as high surgical risk, such as the elderly and the critically ill. We report the occurrence of transient Horner's syndrome and vocal fold paralysis after successful injections of ethanol into a parathyroid adenoma, and discuss the implications and restrictions of the procedure in view of the medical literature.

Acute mastoiditis: a 10-year review

PURPOSE

To study how antibiotic treatment and an early decision to aspirate subperiosteal abscesses can reduce hospitalization periods and costs in patients with acute mastoiditis.

PATIENTS AND METHODS

During a 10-year period, 134 patients were diagnosed with acute mastoiditis at the Department of Ear, Nose, and Throat and Head and Neck Surgery (Kaplan Medical Center, Rehovot, Israel). The diagnoses was based on physical findings of retroauricular swelling and erythema and tenderness, with protrusion of the auricle forward and downward. The majority of patients (77) reached medical treatment during the first 3 days of their disease. Wide myringotomy and intravenous antibiotic treatment, aspiration, and complete cortical mastoidectomy were the treatment options.

RESULTS

With the administration of wide myringotomy and intravenous antibiotic treatment, 115 patients recovered; nine received aspiration and did not need surgery; and only 15 patients who received the antibiotic treatment needed a complete cortical mastoidectomy.

CONCLUSION

With the wise use of antibiotics and early decision to aspirate subperiosteal abscesses, the hospitalization period, the cost, and the need for surgery can be reduced.

HIV, STDs, anal sex and AIDS prevention policy in a northeastern Brazilian city

Data on HIV/AIDS, other STDs, and related sexual practices and AIDS prevention measures in São Luís, capital of Maranhão state, were collected in May-July 1995 using participant-observation fieldwork, including a number of face-to-face interviews in addition to archival research, and were updated by correspondence in 1996-1997 and a brief visit in February 1998. In contrast to the continuing severe AIDS epidemic in southern Brazil, public health statistics and public HIV testing recently instituted in São Luís suggest that HIV infection has remained largely concentrated among men who have sex with men, as well as a few, though growing number of cases of women evidently infected by such men. However, other STDs are endemic to the region, and could provide an increasing portal of entry for HIV infection. AIDS prevention education programmes have commenced in public schools and elsewhere in São Luís, but greater emphasis needs to also be placed on the prevention and treatment of other STDs. As in other regions of Brazil and Latin America, the reportedly common practice of anal sex among heterosexuals also represents a significant yet typically underemphasized risk factor for HIV.

The effect of short-term, temporary deferral on future blood donation

BACKGROUND

Most blood donor deferrals are temporary and short-term. The effect of short-term, temporary deferral (STTD) on blood donor return rates and subsequent blood donations is an important issue.

STUDY DESIGN AND METHODS

Donors given STTDs during the first 3 months of 1993 were computer-matched with nondeferred donors on the basis of age, sex, and donation date. Computer records were evaluated during the next 4.25 years (4/93-6/97) to determine donor return rates and subsequent blood donations.

RESULTS

The most common reasons STTD were low hemoglobin (46%), colds and/or sore throats (19%), and elevated temperature (10%). Nondeferred donors were 29 percent more likely than donors with STTD to return over the next 4.25 years (80% vs. 62%), and nondeferred donors donated 81 percent more whole blood units (13,798 vs. 7,615) over the same period.

CONCLUSION

The study showed that STTD have a very negative impact on blood donor return rates and subsequent blood donations. Actions to alleviate these negative effects are indicated.

Pulmonary tuberculosis in the border region of Chiapas, Mexico

OBJECTIVES

To estimate the prevalence of pulmonary tuberculosis (PTB) in chronic cough patients seeking care at a second level hospital for any complaint, and to identify groups more likely to test TB smear-positive, within the Border Region of Chiapas, Mexico.

METHODS

Active case finding of patients with chronic cough (cough of 15 days or more) was carried out among all patients aged over 14 years seeking care for whatever reason in the only hospital in the region for patients not covered by insurance. The coughers identified (n=221) were interviewed and three sputum samples requested for acid-fast smears. In order to identify groups at greater risk a logistic regression model was constructed.

RESULTS

A rate of 21 positive PTB smears per hundred patients was found (95% Confidence Interval [CI]=15.5-26.6). The main factors associated with positive PTB were age, occupation and weight loss. The subgroup of chronic cough patients of those aged 35-44 years, agricultural workers and those who had lost weight, had the greatest likelihood of positive PTB smears (68.7%).

CONCLUSION

In hospitals that treat rural patients, special efforts should be made to make health personnel more aware of the need to investigate respiratory symptoms in all of their patients, particularly in the subgroups identified with the greatest likelihood of being positive for TB.

Evaluation of chromosome 12 copy number in ovarian granulosa cell tumors using interphase cytogenetics

Trisomy 12 is frequently observed in karyotypes of ovarian sex cord-stromal tumors, including adult and juvenile granulosa cell tumors (AGCTs and JGCTs). We assessed the ability to detect this abnormality in deparaffinized tissue sections of 19 ovarian GCTs (17 AGCTs, two JGCTs) and in one fibrothecoma by simultaneous in situ hybridization with fluorescent-labeled centromeric probes to chromosomes 12 (fluorescein isothiocyanate conjugated) and 17 (rhodamine conjugated). In order to quantitate the artifact introduced by nuclear slicing, such analyses were performed both on intact tissue sections and on cytospins of nuclei prepared by enzymatic dissociation from the corresponding tissue block. The series was also evaluated for numerical abnormalities of chromosome X, a less common cytogenetic finding in GCT. Twelve of 19 cases (63%) displayed evidence of trisomy 12 (defined as signal gain in > or = 10% of nuclei) in the intact section, the cytospin, or both. Trisomy for chromosome 17 was present in one case, and trisomy X was present in two cases. In tissue sections the incidence of signal gain for the chromosome 12 probe varied from 0-45% of nuclei (mean 19%). In cytospin preparations, the percentage signal gain for chromosome 12 ranged from 0 to 84% (mean 33%). This study supports the presence of trisomy 12 as a common, but not defining, cytogenetic anomaly in ovarian GCTs. Its presence, however, within only a minority of tumor cells may be partly explained by slicing artifact associated with intact tissue sections, although partial involvement of intact nuclei suggests that trisomy 12 may also be encountered as a heterogeneous abnormality within neoplastic populations of GCTs.

[Delayed post-anoxic encephalopathy]

A case of the rare condition, delayed postanoxic encephalopathy is presented. This condition occurs after an acute hypoxic insult followed by an interval of apparent full recovery, but relapses to various degrees of renewed neurological impairment, coma or even death. Anesthetists should be aware of this entity and establish proper follow-up in patients at risk.

Bronichiloitis obliterms-current concepts

We review current concepts abut the clinical manifestations,diagnosis and treatment of patients with bronchiolitis obliterans (BO) with emphasis on clinical/pathological correlations and recent developments. BO is a relatively rare disease, but its incidence is probably higher than generally believed and is continuously rising, partly because of better recognition, but also because of increased exposure to industrial fumes, and its occurrence in lung transplantation. BO is characterized histologically by varying degrees of obliteration of the lumen of the respiratory bronchioles by organizing connective tissue often extending into the alveoli (‘proliferative’ BO with organizing pneumoni+BOOP) or by more extensive fibrosis and scarring of the more proximal, conductive bronchioles (‘constrictive’ BO). Diverse clinical conditions have been associated with the development of BO, notably viral and mycoplasma infection, toxic fume exposure and immune reactions in the setting of a collagen vascular disease, drug reaction or organ transplantation. The clinical course and features of BO may vary considerably according to the aetiology, histological pattern and stage of the disease. The most common presentation is that of a progressive dry cough and dyspnea, associated with diffuse patchy interstitial lung infiltrates on chest X-ray. In the more advanced cases, lung function tests show either restrictive or obstructive defects, depending on the extent of alveolar involvement, and hypoxemia without CO₂ retention. The diagnosis is often possible on clinical grounds, however, in a seriously ill patient uncertainty should be resolved by tissue diagnosis, preferably by open lung biopsy. Treatment is based on symptomatic therapy. The use of corticosteroids is controversial, but common. Patients with BOOP are exceptional, in that there may be no underlying condition (‘idiopathic’ BOOP or cryptogenic organizing pneumonia—COP), a restrictive ventilatory defect is usual and the response to corticosteroids often remarkable.

Expression of alpha v and beta 3 integrin subunits in rat osteoclasts in situ

Recent findings suggest that the vitronectin receptor, a member of the integrin family, plays an important role in the attachment of osteoclasts to bone matrix. We report here the localization by in situ hybridization of the mRNA for the alpha and beta subunits of the vitronectin receptor in rat bone sections. To generate the rat-specific RNA probes used in this study, we cloned cDNA fragments of integrin chains alpha v, beta 3, and beta 5 by the polymerase chain reaction from rat cDNA. These fragments share 86-91% homology with the respective human sequences. In situ hybridization localized the alpha v and beta 3 mRNAs to regions undergoing extensive bone resorption. The histologic appearance and prestaining of bone sections for tartrate-resistant acid phosphatase (TRAP) indicated the presence of these mRNAs in osteoclasts. These observations support immunohistochemical findings that osteoclasts express high levels of the vitronectin receptor, confirm the identity of this receptor as integrin alpha v/beta 3, and suggest that osteoclasts may actively synthesize these molecules.

Obstructing adenoids in adolescents: changing trends?

The number of adolescents undergoing surgery for obstructing adenoids has increased significantly in our practice in recent years. Over an 11-year period during which 539 adenoidectomies were performed, the mean age of patients increased progressively from 4.6 years in 1980 to 7.88 years in 1990. The median age gradually increased over the same period from 4 to 7 years, and the standard deviation from 4.95 to 19.38. Enlarged adenoids should be considered in the differential diagnosis of adolescents suffering from nasal obstruction, snoring or obstructive sleep apnea.

Differential expression of insulin-like growth factor-I (IGF-I) and IGF-II messenger ribonucleic acid in growing rat bone

Insulin-like growth factors (IGF-I and IGF-II) are among the most abundant growth factors found in bone. Although their local production has been implicated in growth and development, localization of the cells that express these proteins is not well documented. We have studied, by in situ hybridization, the temporal and spatial expression of IGF-I and IGF-II mRNA in rat long bones at different stages of postnatal bone development. In 2-day-old rats, IGF-II was highly expressed in cartilage and in the mesodermal structures that surround the bone. At later stages of bone development, the IGF-II signal decreased in intensity, but could still be detected in the growth plate of tibial bones at 3 and 5 weeks. At this stage, the IGF-II signal in the epiphyseal growth plate was unevenly distributed and was stronger in the periphery than in the center, where it was mainly concentrated in the germinal layer and in some, but not all, cartilage columns. IGF-I, on the other hand, was only faintly detected in the periosteum at the early cartilaginous stage of bone development. At later stages, IGF-I was strongly associated with regions of ossification in the trabecular bone of the metaphysis and epiphysis and along the endosteal and periosteal surfaces. Surprisingly, we did not detect at any time IGF-I mRNA in chondrocytes of the epiphyseal growth plate. These results suggest that in the rat, IGF-II plays a role in early development of bone and in the longitudinal growth of the epiphyseal plate. IGF-I is more closely associated with the osteogenic regions and does not replace the declining levels of IGF-II in the growth plate.

Paraquat poisoning in southern Mexico: a report of 25 cases

Paraquat is a bipyridyl herbicide used world-wide. Although accidental and deliberate ingestions of lethal doses have been reported from many countries, no case has ever been described in Mexico. The authors report on 25 cases of Paraquat poisoning in the state of Chiapas, Mexico, that occurred between 1988 and 1990. Eighty percent of the cases were men, and 64% of the cases died. Alcohol intoxication or suicidal intent were factors at the time of Paraquat ingestion in 75% of the cases. The majority of cases had learned to use Paraquat from a friend; none had been instructed by a professional. Eighty percent of cases did not know the dilution for the proper use of the herbicide, and none kept the herbicide in its original container. Attention to the law, redesign of the Paraquat packaging, and educational efforts directed at populations at risk might reduce the occurrence of poisoning in this region.

The association of Helicobacter pylori with gastric cancer and preneoplastic gastric lesions in Chiapas, Mexico

BACKGROUND

Helicobacter pylori recently was identified as a risk factor for gastric cancer. Its association with preneoplastic conditions of the stomach, however, is undocumented.

METHODS

Gastric biopsy specimens from 245 symptomatic patients were examined for neoplastic and preneoplastic lesions and for gastric H. pylori infection. The sera of 183 subjects were tested by enzyme-linked immunosorbent assay (ELISA) for anti-H. pylori immunoglobulin G.

RESULTS

Histologic H. pylori infection, usually accompanied by acute and chronic gastritis, was found in 85.7% of patients. There was a strong association between H. pylori in the tissue and atrophy (relative risk, 15.0; 95% confidence interval, 4.2-56.6), intestinal metaplasia (relative risk, 5.7; 95% confidence interval, 1.9-16.8), and dysplasia or cancer (relative risk, 4.0; 95% confidence interval, 1.1-14.8). The ELISA was 93.2% sensitive and 57.1% specific for histologic infection with a positive predictive value of 96.1%. The overall seroprevalence rate was 86.1%, with no significant difference in rates between patients with cancer precursors and those with normal stomachs.

CONCLUSIONS

In this high-risk population, precursor lesions for adenocarcinoma were associated universally with H. pylori infection.

The association of Helicobacter pylori with gastric cancer and preneoplastic gastric lesions in Chiapas, Mexico

BACKGROUND

Helicobacter pylori recently was identified as a risk factor for gastric cancer. Its association with preneoplastic conditions of the stomach, however, is undocumented.

METHODS

Gastric biopsy specimens from 245 symptomatic patients were examined for neoplastic and preneoplastic lesions and for gastric H. pylori infection. The sera of 183 subjects were tested by enzyme-linked immunosorbent assay (ELISA) for anti-H. pylori immunoglobulin G.

RESULTS

Histologic H. pylori infection, usually accompanied by acute and chronic gastritis, was found in 85.7% of patients. There was a strong association between H. pylori in the tissue and atrophy (relative risk, 15.0; 95% confidence interval, 4.2-56.6), intestinal metaplasia (relative risk, 5.7; 95% confidence interval, 1.9-16.8), and dysplasia or cancer (relative risk, 4.0; 95% confidence interval, 1.1-14.8). The ELISA was 93.2% sensitive and 57.1% specific for histologic infection with a positive predictive value of 96.1%. The overall seroprevalence rate was 86.1%, with no significant difference in rates between patients with cancer precursors and those with normal stomachs.

CONCLUSIONS

In this high-risk population, precursor lesions for adenocarcinoma were associated universally with H. pylori infection.

Long-term follow-up of the effectiveness and safety of inferior turbinectomy

The long-term effectiveness and safety of inferior turbinectomy were assessed in 186 patients who were interviewed and examined 10 to 15 years after surgery (mean 12.3 years). Relief of nasal obstruction was reported by 82 percent of the patients; rhinoscopy showed wide, clean nasal airways in 88 percent. Rhinorrhea was still a problem for 34 percent of patients, and 19 percent were receiving medical treatment for this symptom. Smell acuity had improved in 52 percent of the patients. Before turbinectomy, 32 patients had suffered from bronchial asthma; postoperatively, there was an improvement in 16, and no change in 13; 3 patients reported exacerbation of asthmatic attacks. Atrophic changes of the nasal mucosa and chronic purulent infection were not observed in any of the patients.

[Pulmonary edema complicating upper airway obstruction]

A 40-year-old man who developed acute pulmonary edema following relief of upper airway obstruction is presented. The mechanism of pulmonary edema associated with upper airway obstruction is complex and not fully understood. It is therefore difficult to predict which patients will develop pulmonary edema during or after the relief of obstruction.

Immunosuppression by an immunogenic immunomodulating mycobacterial fraction is correlated to changes in phenotype distribution of murine lymphoid cells

Previously reported studies revealed that extensive immunization with the Methanol Extraction Residue (MER) of BCG tubercle bacillus in Incomplete Freund's Adjuvant (IFA) induced marked suppression of T and B cell functions in vivo and in vitro. The purpose of the present work was to determine whether immunosuppression induced by hyperimmunization with MER is correlated with changes in morphological characteristics and in phenotype pattern of spleen and peritoneal lymphoid cells. Hyperimmunization with MER resulted in a marked increase in the number of spleen cells and in enlargement and granulation of spleen and peritoneal cells. Similar changes in size and granulation were also observed in isolated fractions of splenic T and B cells. Extensive immunization with MER also induced marked decrease in the total number of T cells (Thy 1,2 positive). The decrease in T cells was observed in all three T-cell subsets investigated: Lyt-1, Lyt-2 and L3T4 positive. Although the number of splenic B cells was decreased in samples (10,000 cells), taken from MER hyperimmunized mice, this decrease was compensated by overall increase in the number of spleen cells. The marked decrease in the percentage of splenic T cells was counterbalanced by marked increase in the splenic macrophage population: increase in MAC-1, MAC-2 and MAC-3 positive cells. It is concluded that extensive immunization with MER induces morphological changes in spleen and peritoneal cells, marked decrease in the number of splenic T cells and marked increase of the splenic macrophagic population. It is postulated that these changes are correlated with induction of immunosuppression by a similar procedure of extensive immunization with the agent.

Immunological reactivity to a mycobacterial fraction is associated with nonspecific suppression of immunological responsiveness in vivo

Previously reported studies revealed that spleen cells from BALB/c mice immunized against a methanol extraction residue (MER) fraction of tubercle bacilli are defective in the in vitro generation of antibodies to SRBC and in allogeneic responsiveness against C57BL spleen cells. We now show that mice repeatedly immunized with MER also exhibit a depressed capacity to respond to antigenic stimulation in vivo. Thus mice repeatedly injected with MER were impaired in their ability to react to antigenic stimulation by SRBC and by C57BL spleen cells. Impairment in the response to SRBC immunization was expressed at the level of delayed-type hypersensitivity (DTH) as well as of antibody production. The response of MER hyperimmunized mice to contact sensitization with dinitrofluorobenzene (DNFB) was not impaired, but the lymph node cells of DNFB-sensitized animals had a depressed ability to respond to in vitro stimulation by the monovalent hapten dinitrobenzene sulfonate (DNBS). The present findings indicate that extensive exposure to an immunogenic immunomodulating mycobacterial fraction can lead to a depressed responsiveness to unrelated antigenic stimulation.