Spatial mapping of human hematopoiesis at single-cell resolution reveals aging-associated topographic remodeling

ABSTRACT

The spatial anatomy of hematopoiesis in the bone marrow (BM) has been extensively studied in mice and other preclinical models, but technical challenges have precluded a commensurate exploration in humans. Institutional pathology archives contain thousands of paraffinized BM core biopsy tissue specimens, providing a rich resource for studying the intact human BM topography in a variety of physiologic states. Thus, we developed an end-to-end pipeline involving multiparameter whole tissue staining, in situ imaging at single-cell resolution, and artificial intelligence-based digital whole slide image analysis and then applied it to a cohort of disease-free samples to survey alterations in the hematopoietic topography associated with aging. Our data indicate heterogeneity in marrow adipose tissue (MAT) content within each age group and an inverse correlation between MAT content and proportions of early myeloid and erythroid precursors, irrespective of age. We identify consistent endosteal and perivascular positioning of hematopoietic stem and progenitor cells (HSPCs) with medullary localization of more differentiated elements and, importantly, uncover new evidence of aging-associated changes in cellular and vascular morphologies, microarchitectural alterations suggestive of foci with increased lymphocytes, and diminution of a potentially active megakaryocytic niche. Overall, our findings suggest that there is topographic remodeling of human hematopoiesis associated with aging. More generally, we demonstrate the potential to deeply unravel the spatial biology of normal and pathologic human BM states using intact archival tissue specimens.

Molecular and Cytogenetic Education in Hematopathology Fellowship

OBJECTIVES

Given the increased complexity of molecular and cytogenetic testing (MOL-CG), the Society for Hematopathology Education Committee (SH-EC) was interested in determining what the current expectations are for MOL-CG education in hematopathology (HP) fellowship training.

METHODS

The SH-EC sent a questionnaire to HP fellowship program directors (HP-PDs) covering MOL-CG training curricula, test menus, faculty background, teaching, and sign-out roles. These findings were explored via a panel-based discussion at the 2018 SH-EC meeting for HP-PDs.

RESULTS

HP fellows are expected to understand basic principles, nomenclature, and indications for and limitations of testing. Interpretation of common assays is within that scope, but not necessarily proficiency in technical troubleshooting of testing or analysis of complex raw data.

CONCLUSIONS

The consensus was that HP fellows should understand the components of MOL-CG testing necessary to incorporate those results into an accurate, clinically relevant, and integrated HP report.

Abstract P4-10-06: Influence of older age on triple negative breast cancer (TNBC) clinical-pathological characteristics and outcomes

Background: The impact of age at diagnosis on clinical presentation and treatment delivery for triple negative breast cancer (TNBC) is unclear. Utilizing data from a prospective registry, the aim of this study was to further elucidate the age-dependent correlation between TNBC clinical-pathological features, and the implications of age-bias on treatment delivery and prognosis.

Methods: 480 subjects with stage I-III TNBC were enrolled in an IRB approved multisite prospective registry between 2011 and 2016. Clinical, demographic, treatment information was collected and patients were followed for recurrence and survival. Patients were categorized as older (>60 years) or younger groups (<60 years). Recurrence free survival (RFS) and overall survival (OS) were estimated according to the Kaplan-Meier method and compared among groups by log-rank test.

Results: 145 (30%) of 480 TNBC patients were older (> 60 years) at time of diagnosis. Compared to younger patients, older patients were more likely to present with screen detected vs symptomatic cancer (47% vs 25% p=<0.001), more likely to have node negative cancer (71% vs 61% p=0.030), stage I disease (42% vs 28% p=0.003), and low level (1-10%) ER or PR positivity (19% vs 12% p=0.046). Compared to the younger patients, older patients were less likely to have a BRCA1/2 mutation (6% vs 23% p=0.0002) but more likely to have a prior history of hormone positive breast cancer (7% vs 1% p=0.0002). Compared to younger counterparts, older patients were less likely to receive neo/adjuvant chemotherapy (93% vs 99% p=0.0006), and less likely to receive > 4 cycles of neo/adjuvant chemotherapy (61% vs 78%, p=0.0003). Three year RFS for the entire cohort was 80% and was identical for older and younger patients at 80%. Three year OS for the entire cohort was 87% and was similar for older and younger patients. On multivariable analysis only tumor size and nodal status significantly impacted RFS.

Conclusions: A significant fraction (30%) of TNBC patients are older (> 60 years) at time of diagnosis. Despite presenting a with more favorable disease stage, older TNBC patients did not demonstrate better outcomes compared to the higher risk younger patients. The underlying reasons for this observation may be tumor biology differences between older and younger TNBC patients or perhaps could be related to underutilization of appropriate systemic chemotherapy (39% of older patients received < 4 cycles of chemotherapy). Further studies are warranted on this subject.

Citation Format: Mina A, Lehn C, Wang YY, Klemp JR, O'Dea AP, Elia M, Hoffmann M, Crane G, Sheehan M, Madhusudhana S, Jensen RA, Godwin AK, Khan QJ, Kimler BF, Sharma P. Influence of older age on triple negative breast cancer (TNBC) clinical-pathological characteristics and outcomes [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-10-06.

Abstract P5-16-02: Pathological complete response is associated with excellent outcomes in BRCA mutation associated triple negative breast cancer

Introduction: Pathological complete response (pCR) in unselected triple negative breast cancer (TNBC) is associated with excellent long-term survival. However, controversy remains as to whether pCR in BRCA mutation associated (BRCA[+]) TNBC is predictive of improved long-term outcome. A recent study suggests that pCR was not a surrogate for outcomes in BRCA1 associated TNBC. All of the patients in this study harbored an Ashkenazi Jewish founder BRCA1 mutation and the majority of mutation carriers underwent lumpectomy. Impact of pCR as it relates to BRCA status in a larger, heterogeneous TNBC cohort treated in a contemporary time frame is not known.

Aim: Evaluate and compare the prognostic impact of pCR as it relates to the BRCA mutation status in patients enrolled in a prospective multisite TNBC registry.

Methods: 453 patients with stage I-III TNBC were enrolled within a multisite registry between 2011- 2015, out of which 173 received neoadjuvant chemotherapy (NAC) and also underwent germline BRCA testing. pCR in the breast and axilla was evaluated and patients were followed for reoccurrence and survival. Recurrence free survival (RFS) was estimated according to the Kaplan-Meier method and compared among groups with log-rank statistic.

Results: For the 173 eligible patients the median age was 49 years; African-American:14%; median tumor size:3 cm; 42%:Lymph node positive; and 18% (32/173) demonstrated BRCA mutation (BRCA1=28, BRCA2=4). All patients received anthracycline and/or taxane based NAC. pCR rates for BRCA[+] and wild type (BRCA[-]) patients was 72% and 46% respectively (p=0.01). 97% of BRCA[+] and 42% of BRCA[-] patients underwent bilateral mastectomy (p=0.001). The three year RFS was 92% and 81% in BRCA[+] and BRCA[-] patients, respectively (p=0.18). Attainment of pCR was associated with excellent 3 year RFS of 95% and 97% in BRCA[+] and BRCA[-] patients, respectively (p=0.85). Among BRCA[-] patients lack of pCR was associated with significantly worse 3 year RFS (70% RFS in patients without pCR, compared to 97% in patients with pCR; p=0.001). Among BRCA[+] patients lack of pCR was associated with numerically lower but not statistically significant worse 3 year RFS (83% RFS in patients without pCR, compared to 95% in patients with pCR; p=0.41). On multivariable Cox regression analysis, only stage III disease was associated with higher risk of relapse (p<0.001).

Conclusions: Our observation of higher pCR in BRCA-carriers compared to wild-type TNBC patients is consistent with previously published literature. In this contemporary cohort of TNBC patients for whom the majority of BRCA[+] patients underwent bilateral mastectomy, attainment of pCR carried an excellent prognosis in both BRCA[+] and BRCA[-] patients. On the other hand, BRCA[+] patients who do not attain pCR may have better outcomes compared to BRCA[-] patients without pCR. Further research to explore the underlying biological mechanisms involved in tumor response and relapse in BRCA[+] and BRCA[-] TNBC patients is needed. Furthermore, given these observations, germline BRCA mutation status should be used as a stratification variable in studies evaluating pCR and long term outcomes with investigational therapies in TNBC.

Citation Format: Prochaska LH, Godwin AK, Kimler BF, Lehn C, Klemp JR, O'Dea A, Elia M, Hoffmann MS, Crane G, McKittrick R, Sheehan M, Graff SL, Madhusudhana S, Khan QJ, Jensen RA, Sharma P. Pathological complete response is associated with excellent outcomes in BRCA mutation associated triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-16-02.

A massive pelvic mucocele presenting as a cystic sacral mass

We present a man, with a complex medical and surgical history, who had a large pelvic non-appendiceal cystadenoma, presenting as a cystic sacral mass causing obstructive urinary symptoms and renal failure. Mucocele should be included in the differential diagnosis of patients who present with large sacral masses, and who have a significant history of pelvic and abdominal surgery and inflammatory bowel disease.

Symptoms of hand-arm vibration syndrome in gas distribution operatives

OBJECTIVES

To survey the prevalence and severity of hand-arm vibration syndrome symptoms (HAVS), and to estimate past and current exposure to hand held vibrating tools in a sample of gas distribution operatives breaking and re-instating road surfaces.

METHODS

153 gas distribution operatives (participation rate 81%) from three company districts were assessed by an administered questionnaire, a clinical examination, and a simple cold challenge test to the hands. Exposure histories were taken aided by a picture album of past and current tools. Information was obtained from several sources on the likely vibratory characteristics of those tools. Estimates were thus obtained of the frequency of blanching and neurological complaints in operatives, and of their lifetime hours of exposure and lifetime dose of vibration.

RESULTS

On average, the sample had spent 16 years in employment involving use of vibratory tools. 24% had symptoms or signs of blanching after use of tools in the industry; 46% had troublesome persistent complaints of paraesthesiae or numbness, and these symptoms extended into the hands or arms in 18% of workers. In 5.9% the distribution of symptoms was suggestive of carpal tunnel syndrome; and of ulnar nerve entrapment in a further 3.9%. The risks of blanching and neurological complaints rose significantly with lifetime hours of use of vibrating tools and lifetime dose of vibration. Symptoms were generally mild and apparent only after a prolonged interval, but there were exceptions, and cases had occurred after lower recent exposures.

CONCLUSIONS

It has been suggested that aspects of the gas distribution operative's work mitigate against the risk normally anticipated from use of pneumatic road breaking tools. By contrast our data suggest that symptoms of HAVS do occur, given sufficient exposure, a finding relevant not only to gas supply workers, but also to workers from other industries who break and repair road surfaces.

Bone mineral density and broadband ultrasound attenuation with estrogen treatment of postmenopausal women

The purpose of the current study was to determine the changes in lumbar spine, hip, and calcaneus bone mineral density (BMD), and in calcaneus broadband ultrasound attenuation (BUA) in early menopausal women and to assess the effects of estrogen replacement therapy (ERT) on bone mass at these sites over a 2-yr period. Fifty-three Caucasian women who were at least 6 mo postmenopausal were divided into two groups based on estrogen use. Twenty-one women, average age 53.0 +/- 0.6 yr and 2.9 +/- 0.3 yr since menopause, had been receiving estrogen in combination with progesterone for at least 6 mo prior to enrollment in the study. Thirty-two women, average age 52.7 +/- 0.8 yr and 2.8 +/- 0.3 yr since menopause, had never received ERT. During the 2-yr study, women not receiving ERT had significant decreases in BMD of the spine -2.3 +/- 0.6%, femoral neck -2.2 +/- 0.8%, and calcaneus -4.7 +/- 0.9%, and in BUA of the calcaneus -14.3 +/- 1.8%. ERT prevented the decreases in BMD at the spine +0.4 +/- 0.6% and calcaneus -2.3 +/- 1.1%, but did not prevent a significant decrease in bone mass at the femoral neck -1.9 +/- 0.8% and BUA at the calcaneus -17.8 +/- 3.2%. Neither group had significant decreases in total hip BMD. This study demonstrates again that ERT prevents the menopause-associated decreases in spine BMD. However, in this group of women, ERT did not prevent loss in femoral neck BMD or BUA. The results suggest that women being treated with estrogen for maintenance of BMD in early menopause need to be monitored to ensure efficacy of therapy, especially in the maintenance of femoral neck BMD.

Respiratory disease in workers exposed to colophony solder flux fumes: continuing health concerns

The objectives of this study were to establish the prevalence of respiratory, eye, nose and throat symptoms of likely work-relation in workers exposed to colophony solder flux fumes and to assess their lung function. A cross-sectional study was conducted in four medium-sized electronics firms in which control measures to capture solder flux fume were absent or visibly ineffective. All female solders and women working adjacent to soldering stations completed an administered questionnaire concerning symptoms, work history and current soldering frequency. Measurements were made of their forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) during the course of a working shift, using a Vitallograph-Compact portable spirometer. Using weekly hours of soldering as a crude index of current exposure, workers were classified into high (> or = 37 h/wk) and low (< or = 20 h/wk) exposure groups, and their health responses were compared in the analysis. Individuals with symptoms suggestive of work-related asthma were also asked to provide serial peak flow measurements over a further 2-week period, and adequate returns were charted and read by two physicians experienced in the diagnosis of occupational asthma. Data were collected on 152 female workers (overall participation rate = 97%). Symptoms of recurrent, persistent wheeze and/or chest tightness were reported by 75 (49%) of interviewees; 36 (24%) gave a history typical of occupational asthma and six more (4%) a history of pre-existing asthma worsened at work. Twenty-one (14%) of the workforce complained of recurrent breathlessness on moderate exertion; 41 workers (27%) had work-related symptoms of the nose or throat and 25 (16%) had work-related eye symptoms. The odds ratios for 'all wheeze', shortness of breath, and work-related eye, nose and chest symptoms were all significantly greater (raised about 4-5 fold) in women who soldered > or = 37 h/wk when compared with those soldering < or = 20 h/wk. After adjustment by logistic regression for atopy, age and smoking status even higher risk estimates were generally obtained. The odds ratios (OR) and 95% confidence intervals (CI) for high vs. low were: for 'all wheeze', OR = 7.2, CI = 2.5-20.7; for work-related eye symptoms, OR = 5.2, CI = 1.4-19.8; for work-related nasal symptoms, OR = 4.0, CI = 1.4-11.1 and for occupational asthma symptoms, OR = 5.2, CI = 1.4-14.2. Mean FEV1 and FVC percentage difference from expected were slightly lower in full-time solderers than in part-time solderers, but the differences were not significant. Thirty-seven of the 51 workers (73%) who were asked to carry out serial peak flow measurements completed an adequate return: 27 of these records confirmed the presence of asthma, and in all of the cases the history suggested onset post-dating employment in soldering. Eleven peak flow records were indicative of occupational asthma. The health problems associated with colophony solder flux were documented over 18 years ago, but are still clearly apparent in situations where adequate control has not been achieved.

Health and safety behaviour and compliance in electroplating workshops

Skin problems are reputedly common in electroplaters. To examine the steps taken by employers and employees to prevent or control skin problems, we visited six randomly selected electroplating establishments in Dorset and interviewed the employers and 50 of the employees using structured questionnaires. Several of the companies had not complied with the statutory requirements of the Control of Substances Hazardous to Health (COSHH) Regulations 1988, and deficiencies were evident in assessment, control and health surveillance. A third of the employees had current or recent work-related skin problems, typically dermatitis. Workers were generally ignorant about the hazards of materials handled. They knew about personal protective equipment, but did not always use it, or used gloveware that was deficient or contaminated. Only one in five employees adopted a rudimentary skin care programme; many were unaware of the provision for skin care. There is an urgent need for better training and more attention to skin care in electroplating workshops.

Bacteriology of urinary tract stones

It has been reported that up to half of renal stones and associated urine specimens have been positive on culture, and that up to 50% of such stones contain magnesium ammonium phosphate. In a prospective study using infrared and wet chemical analysis, we found positive cultures in only 7 of 132 renal, 5 of 105 ureteral and 6 of 21 bladder stones obtained surgically and handled with sterility. Of the culture positive calculi only 43% from the kidney, none from the ureter and 50% from the bladder contained detectable magnesium ammonium phosphate. However, magnesium ammonium phosphate was detectable in 20% of renal, 2% of ureteral and 27% of bladder stones with negative cultures. Of the culture positive renal and ureteral calculi 42% were predominantly calcium phosphate and 17% were predominantly calcium oxalate. For culture negative stones 25% and 51% from the kidney, and 15% and 82% from the ureter were composed of predominantly calcium phosphate and calcium oxalate, respectively. Among the culture positive stones, related positive urine cultures were noted in 100% of the renal, 20% of the ureteral and 50% of the bladder cases, compared to 26%, 10% and 27%, respectively, of culture negative calculi. The same organism was found in the stone and urine in only 38% of the cases. The lower frequency of positive urine cultures, of stones with magnesium ammonium phosphate, and especially of culture positive renal and ureteral stones (5%) than in previous reports suggests that stone culture may be of less value than indicated previously, except for bladder calculi and large renal stones, such as the branched type.

Difficulties of interpreting PPD reactions of women living in Madang, Papua New Guinea

Malaria surveys in Madang, Papua New Guinea, previously distinguished 2 populations of women with significantly different spleen rates and immune responses to malaria. Differences between the high (HS) and low (LS) spleen rate groups suggested a defect in cellular immunity in the HS group. This paper reports a survey of purified protein derivative (PPD) responses in a sample of HS and LS women. Eighty-eight of 162 women were PPD positive (reaction size > 5 mm). There was a marked difference in the range and size of PPD reaction between the HS and LS groups. Mean size in the LS group was 20.7 mm and in the HS group it was 12.1 mm (P = 0.02). Failure to show differences in other indicators of specific malaria immunity indicated that the difference in PPD response was not the result of malaria-specific cell-mediated immune suppression. Many women were PPD non-responders in spite of evidence of multiple bacillus Calmette-Guérin (BCG) vaccination scars. There was no difference between HS and LS groups in the level of non-response to PPD. The results confirm an early tuberculosis survey indicating that New Guineans rapidly lose PPD reactivity to BCG vaccination. Ability to maintain a PPD response, and the quality of response, may vary according to sex and genetic background.

Single X-ray absorptiometry of the forearm: precision, correlation, and reference data

The performance of a single X-ray absorptiometry (SXA) device incorporating an X-ray tube as a photon source was evaluated with respect to precision in vivo and in vitro, scan time, image quality, and correlation with an existing dual energy X-ray absorptiometry (DXA) device. SXA precision in vivo, expressed as a coefficient of variation (CV), was 0.66% for bone mineral content (BMC) and 1.05% for bone mineral density (BMD). Precision in vitro, based on 78 BMC measurements of a forearm phantom over 195 days, was 0.53%. Correlation with DXA at the 8 mm distal forearm site was high (r = 0.97 for BMC and r = 0.96 for BMD). A preliminary SXA reference database composed of 151 healthy Caucasian American women was developed to facilitate the interpretation of patient measurements. SXA scan time was 4 minutes and delivered a radiation exposure of 1.68 mrem. SXA image quality and spatial resolution were superior to SPA and comparable to DXA.

Red cell enzyme and serum protein types in the Watut Anga of Papua New Guinea

Historically, the Angan populations of Papua New Guinea have maintained a strong isolation and absorbed limited genes from their neighbours. This lack of intermixing is reflected in their relatively homogeneous cultural, linguistic and genetic profiles. We have determined the electrophoretic variation at 26 red cell enzyme, serum protein and haemoglobin loci in the Watut Anga, a splinter group occupying the Upper Watut Valley of Morobe Province. Their genetic profile reveals the lack of a number-of variants, such as PGM2*10 and MDH*3, known to exhibit high frequencies in other highland populations. The average heterozygosity in the Watut is also much lower when compared with other Papua New Guinean populations. Their present numerical strength notwithstanding, it appears that the Angan populations have experienced population bottlenecks in their evolutionary history which may have accentuated their genetic divergence from other Papua New Guinean populations.

Role of the capsulo-ligamentous structures in rotation and combined flexion-rotation of the lumbar spine

We carried out experiments on whole cadaveric lumbar spines in order to determine the role that each of the capsulo-ligamentous structures play in axial rotation in the neutral position and in the flexed position. Eight specimens were first tested intact, then after division of all the apophyseal joint capsules between L1 and the sacrum. Another five specimens were also first tested intact, then after division of the supra- and interspinous ligaments and yellow ligament, and finally after cutting the posterior longitudinal ligament and posterior annulus at each level as well. The results show that there is considerable variation in the axial rotation of the lumbar vertebrae within the same spine and across different spines. The apophyseal joint capsules limit rotation both in neutral and flexed positions. In flexion, the amplitude of rotation in the lumbar spine is reduced. Of the capsulo-ligamentous structures, it is the posterior annulus and the posterior longitudinal ligament that seem to play the more important role in limiting axial rotation while the spine is flexed.

Analysis of HLA class II allogenotyping in Australian Aborigines and Papua New Guinea populations

Human leukocyte antigen (HLA) class II allogenotyping has been applied to investigate the polymorphism of the DRB, DQB1, DQB2, DQA1, and DQA2 genes in Aborigines from the East Coast of Australia and in Melanesians from the Papua New Guinea North-East Coast and Highlands. Three new DR/DQ arrangements were observed, DRw14/DQB1-2b/DQA1-1a and DRw5Nauru/DQB1-3a/DQA1-2 (n Australian Aborigines), and DRw5Nauru/DQB1-1a/DQA1-1b (in Madang). DQA2 and DQB2 allogenotyping with TaqI and PstI digested genomic DNA revealed little polymorphism among the Papua New Guineans, with DQA2-Xa1 and DQB2-Xb1 the most common alleles in all the groups. However, the presence of DQA2-Xa2 in Papuans and Australian Aborigines reflects the degree of admixture with Caucasoids while the DQA2-Xa4 allele in Madang is probably a marker of Mongoloid origin.

AIDS and infection control in dermatologic surgery

In summary, the AIDS epidemic has created many new questions for the dermatologist, with no clear answers. As dermatologic surgery is increasing in most dermatology practices, the dermatologic surgeon must take a careful look at his office techniques and educate his personnel on the proper handling of blood and body fluids. The medical and ethical issues raised by the AIDS epidemic are complex, with new issues being raised as more is learned about the disease. The adage "do no harm" should be kept in mind in the counseling, diagnosis, and treatment of HIV-infected individuals.

The genetic basis of hyperreactive malarious splenomegaly

Hyperreactive malarious splenomegaly (HMS) represents an abnormal immune response to recurrent malaria, characterized by excessive production of both IgM and IgG antibodies. It has both a racial and a familial distribution in various parts of the world. Immune responses to many foreign antigens, including those of malaria, are under genetic control of the major histocompatibility locus (MHC), through the influence of HLA antigens on regulatory T-lymphocyte activity. It is therefore likely that this region also contains the genetic determinants for HMS, which would be reflected in associations between HMS and particular HLA antigens or haplotypes. Genetic studies of the Watut people of Papua New Guinea have not shown any association between HMS and a wide range of red cell and serum polymorphisms. However, HMS in this group is associated with the class II HLA antigen DR2, and with high levels of HLA heterozygosity. Formal genetic analysis of family data also points to a sex-linked gene as a further determinant of overresponsiveness to malaria in the Anga. These findings suggest that more than one genetic system may be involved in the development of HMS, and that the combined effects of several genetic determinants may be responsible for the extraordinarily high frequency of HMS found in the Upper Watut Valley.

Two populations of women with high and low spleen rates living in the same area of Madang, Papua New Guinea, demonstrate different immune responses to malaria

Specific malaria and total IgM antibody responses were measured in 2 linguistically distinct coastal Papua New Guinean populations living in the same endemic malarious area, but exhibiting different adult female spleen rates (51% and 30%), in order to establish whether the higher spleen rates in the former group were due to hyper-reactive malarious splenomegaly (HMS). Malaria parasite rates were comparable, and geometric mean titres of IgG malaria antibody were the same, in both groups, indicating comparable exposure to malaria. A higher mean total IgM was observed in the high spleen (HS) rate group (6.07 g/litre, compared with 4.62 g/litre), a higher proportion was seropositive for IgM antibody to Plasmodium falciparum (63% compared with 54%), and HMS was found rather more frequently (4.7% compared with 2.6%). In both groups total IgM concentrations increased significantly with rising parity, and the mean level of 5.27 g/litre in young nulliparous women from the HS group suggested that IgM levels in this group at least were elevated from childhood. In both groups a rise in total IgM was associated with higher P. falciparum IgM geometric mean titres of antibody activity, a fall in parasite rates (HS group: 30% to 15%, P = 0.02; LS group: 24% to 0%, P = 0.034), and higher spleen rates (HS group: 38% to 65%, P = 0.001; LS group: 20% to 67%, P = 0.00012). It is concluded that the difference in spleen rates between the 2 groups was the result of differing degrees of acquired immunity to malaria, probably due to genetic differences in immune responses.(ABSTRACT TRUNCATED AT 250 WORDS)

Inhibition of intra-erythrocytic growth of Plasmodium falciparum by human sera from Papua New Guinea

Plasmodium falciparum was cultured through a single intra-erythrocytic cycle of growth in the presence of sera from various areas of Papua New Guinea. Of 194 sera tested from healthy individuals or subjects with hyperreactive malarious splenomegaly (HMS), 107 (55%) significantly inhibited parasite development. Inhibition did not correlate with malaria experience or HMS, though it was to some extent a seasonal phenomenon. Sera with inhibitory activity lost this after dialysis. A possible explanation for these findings is the occurrence of a dietary toxin with antimalarial properties detectable in vitro.

HLA and tropical splenomegaly syndrome in the Upper Watut Valley of Papua New Guinea

Tropical splenomegaly syndrome (TSS) develops as a result of an atypical immune response to recurrent malarial infection. In general a low prevalence disorder, in the Upper Watut Valley of New Guinea TSS affects more than 80% of the inhabitants. We have studied the association of antigens and haplotypes of HLA-A,B,C, DR, and DQ loci with the severity of TSS as judged by the degree of splenomegaly in 77 unrelated Watut. The study confirmed the previously observed lack of association of TSS with HLA-A and B locus antigens. By contrast, HLA-DR2 was found to be more frequent in patients with gross splenomegaly than in those with moderate splenic enlargement. No two-locus haplotypes were, however, found to be significantly associated with TSS.

HLA studies of Highland and Coastal New Guineans

The HLA profile of three New Guinean populations, two Highland (Asaro, Watut), and one Coastal is presented. The Highland populations are characterized by a low average number of alleles segregating at the HLA loci and also by a low mean value of heterozygosity at these loci. The genetic affinities of the two Highland groups with other Melanesian populations in the Pacific are remote. The Coastal group, on the other hand, shows strong similarities in its antigenic diversity and haplotypic combinations with other Melanesian populations. Nonetheless, the two Highland groups show significant divergence from each other in terms of allelic and haplotypic frequencies. Two different waves of migration settled in the Highlands of New Guinea between 10,000 and 15,000 years ago, and it is possible that the Watut, an Angan speaking group, represents the remnants of the first migration into the interior, whereas the Asaro, members of the Eastern Central family of the Trans-New Guinea phylum, arrived at a later date.

Malaria and tropical splenomegaly syndrome in the Anga of Morobe Province

The Hamtai speaking Anga of the Upper Watut valley have long been considered to be unique in their response to recurrent malaria. Given sufficient exposure, the vast majority develop tropical splenomegaly syndrome concomitantly with their acquisition of effective immunity, whereas elsewhere this disease occurs sporadically. The present study indicates that the Menya of the Tauri valley, a related Angan group, respond similarly, in terms of frequency and degree of gross splenomegaly. On the other hand, the Kapau valley, the traditional homeland of the Hamtai, lying between the Watut and Tauri valleys, remains for the most part free of malaria. It is suggested that all Anga will respond to recurrent malarial infection in the same atypical manner; and that this response results from lack of appropriate genetically-determined mechanisms for mounting efficient immune responses to this infection, significant exposure to which is a relatively recent event for these people.

Scrap Tire Disposal Procedures

Many procedures and processes for the disposal of scrap tires are available. Because of the complexity of the whole disposal problem—e.g., collection logistics, availability and location of markets for products generated from scrap tires, as well as economics—no one procedure or process is believed to be sufficiently outstanding that all scrap tires would be so processed. Several procedures or processes must be used to solve this industry problem. The procedure or process selected for disposing of scrap tires will be dictated primarily by economics and geographic location. Certainly, all procedures must be proven environmentally acceptable.

Blood levels and management of lithium treatment

The limited value of plasma measurements in the management of treatment with lithium is discussed in the light of the mechanisms of its therapeutic actions and toxic effects.The plasma level of lithium usually rises twofold or threefold in the three to five hours after ingestion of each dose of delayed-release tablets and then gradually falls. The precise shape and height of the lithium curve depend on gastric emptying, which can be slowed with propantheline or speeded with metoclopramide. Depressed or demented patients may be irregular in taking their tablets and variable in food intake. Both the time of the blood test and this behaviour must be considered before changing the prescribed dose of lithium salt because of a laboratory result. A lithium tolerance curve may be a safer guide to treatment than single measures.Mild intermittent thirst is a common early side effect, and severe persistent thirst with polyuria is an uncommon later effect of daily intakes of at least 1,500 mg lithium carbonate. This diabetes insipidus is reversible, non-progressive, unrelated to plasma level, and distinct in attack from lithium-induced hypothyroidism, which may occur at low dosage but is also usually of late onset and reversible or treatable with thyroxine while lithium is continued. Obesity is another occasional effect of large doses. These side effects and the antimanic and prophylactic effects may have different mechanisms.

Scrap Tire Disposal

Our overall objective in presenting this review is to call attention to the very complicated nature of the entire disposal problem. The whole field of scrap-tire disposal is full of alternatives, compromises, legislation, and conflicting reports on technological success. We will present a brief historical section explaining why the disposal of scrap-tires is now a problem (challenge) and the events that lead to it. Statistics on the annual volume of scrap-rubber generated and the volume disposed of by major processes will be reviewed. Existing and proposed legislation will be presented, and the probable impact on the rubber industry discussed. We will state what we believe to be the characteristics of an ideal solution. The technical aspects of scrap-tire disposal will not be neglected. The physical, thermal, and chemical values of a scrap-tire will be presented as a basis of defining potential uses for scrap-tires. The existing and proposed uses of scrap-tires as well as processes for disposal are extremely varied. We have decided to discuss processes for scrap-tire disposal under three general categories: physical applications, recovery of fuel value, and chemical processes. Certainly there are processes which overlap these artificial categories. We have concentrated on literature published in the last five years as a means of updating the reader. Private communications are liberally referred to in our review simply because this is the only way some information is available. We have also concentrated on large-volume uses or processes which have the potential for large volume. These uses or processes may be an immediate solution. However, we have also endeavored to record or comment on all ideas for scrap-tire disposal. Finally, we have expressed our opinion as to future trends.