Abstract PO-094: Financial hardship associations with presenteeism and absenteeism among survivors and informal caregivers during cancer treatment

Purpose: People with low perceived work performance and those who are absent from work may be at increased risk for negative employment and financial outcomes during cancer treatment. Thus, we evaluated associations between reports of financial hardship and cancer survivors' and caregivers' perceived work performance and absenteeism. Methods: Participants were surveyed during a larger study on symptom management in survivor-caregiver dyads. We limited to respondents who were employed (N=165). Survey variables included employment status, work performance, sociodemographics, perceived work performance in the prior week, performance in the prior year, and absences from work in the prior week using items from the World Health Organization Health and Work Questionnaire, and financial hardship. Financial hardship included four questions asking whether participants' income met their financial needs, adequacy of financial resources to pay for needs, and for caregivers, whether caregiving had caused financial strain. We summarized sociodemographics and conducted regression analyses to evaluate associations between presenteeism and absenteeism and financial hardship, controlling for sociodemographic factors. Results: On average, caregivers were 50.0 years (Standard Deviation (SD): 13.4) and survivors were 53.9 years (SD: 10.4). The most common relationship between survivors and caregivers was caregivers being spouses (41.7%) and children (22.9%). Caregivers reported working at higher rates (53.9% vs 22.1%, p<0.001) and more hours than survivors (Mean=34.8 vs 33.6 hours, p=0.77). Survivors reported their job performance as 79.5% while caregivers reported theirs as 83.1% on a 0-100% scale. In the week prior, survivors reported absence from work for 0.95 hours while caregivers reported 0.84 hours. In the year prior to diagnosis, survivors and caregivers reported higher than current performance (84.4% and 85.2%, respectively). Caregivers whose finances were adequate to pay for the things they needed for caregiving reported 5.8% higher job performance in the prior year compared to those whose finances did not cover their caregiving expenses (95% Confidence Interval: 0.17-11.5, p=0.04), when controlling for sex, ethnicity, race, income, and education. Conclusions: Cancer patients and caregivers suffer work performance problems during cancer treatment, and this may influence their quality of life. Spouses and children of cancer survivors missed work and reported not working up to their prior performance level. Interventions to address symptom management and psychological distress may decrease absenteeism, promote higher perceived job performance, and allow more survivors and their caregivers to maintain or return to stable employment. Young adult cancer survivors and caregivers, who are still establishing themselves in careers and financially, may especially benefit from these interventions and flexible workplace policies.

Citation Format: Echo L. Warner, Jessica G. Rainbow, Alla Sikorski, Chris Segrin, Terry Badger. Financial hardship associations with presenteeism and absenteeism among survivors and informal caregivers during cancer treatment [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-094.

Comparison of different models of motion in a crowded environment: a Monte Carlo study

In this paper we investigate the motion of molecules in crowded environments for two dramatically different types of molecular transport. The first type is realized by the dynamic lattice liquid model, which is based on a cooperative movement concept and thus, the motion of molecules is highly correlated. The second one corresponds to a so-called motion of a single agent where the motion of molecules is considered as a random walk without any correlation with other moving elements. The crowded environments are modeled as a two-dimensional triangular lattice with fixed impenetrable obstacles. Our simulation results indicate that the type of transport has an impact on the dynamics of the system, the percolation threshold, critical exponents, and on molecules' trajectories.

Structure, physicochemical and biological properties of new complex salt of aqua-(nitrilotriacetato-N,O,O',O")-oxidovanadium(IV) anion with 1,10-phenanthrolinium cation

The crystal structure of new 1,10-phenathrolin-1-ium aqua-(nitrilotriacetato-N,O,O',O")-oxidovanadium(IV) semihydrate of molecular formula (phenH)[VO(NTA)(H2O)]∙1/2H2O was determined. This is the first example of structurally characterized compound that comprises a distinctly separated, monomeric [VO(NTA)(H2O)](-) coordination entity. The crystallographic measurements have subsequently been complemented by the IR spectroscopic characterization and thermal analysis. Furthermore, the electrochemical (cyclic voltammetry) as well as spectrophotometric (UV-vis) studies revealed that the compound is capable of scavenging the superoxide free radicals (O2(-)) as well as stable organic radicals i.e. 2,2'-azinobis(3-ethylbenzothiazoline-6 sulfonic acid) cation radical (ABTS(+)) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), but its reactivity towards radicals is lower than that of VOSO4. Finally, biological properties of the complex in the range of 1-100 μM were investigated in relation to its cytoprotective activity against the oxidative damage generated exogenously by using hydrogen peroxide in the hippocampal neuronal HT22 cell line (the MTT and LDH tests). It has been established that in contrast to VOSO4 the title compound protects the HT22 from the oxidative damage. The paper presents a new perspective for oxidovanadium(IV) complexes as candidates for novel, low-molecular mass cytoprotective agents.

An inherited NBN mutation is associated with poor prognosis prostate cancer

BACKGROUND

To establish the contribution of eight founder alleles in three DNA damage repair genes (BRCA1, CHEK2 and NBS1) to prostate cancer in Poland, and to measure the impact of these variants on survival among patients.

METHODS

Three thousand seven hundred fifty men with prostate cancer and 3956 cancer-free controls were genotyped for three founder alleles in BRCA1 (5382insC, 4153delA, C61G), four alleles in CHEK2 (1100delC, IVS2+1G>A, del5395, I157T), and one allele in NBS1 (657del5).

RESULTS

The NBS1 mutation was detected in 53 of 3750 unselected cases compared with 23 of 3956 (0.6%) controls (odds ratio (OR)=2.5; P=0.0003). A CHEK2 mutation was seen in 383 (10.2%) unselected cases and in 228 (5.8%) controls (OR=1.9; P<0.0001). Mutation of BRCA1 (three mutations combined) was not associated with the risk of prostate cancer (OR=0.9; P=0.8). In a subgroup analysis, the 4153delA mutation was associated with early-onset (age ≤ 60 years) prostate cancer (OR=20.3, P=0.004). The mean follow-up was 54 months. Mortality was significantly worse for carriers of a NBS1 mutation than for non-carriers (HR=1.85; P=0.008). The 5-year survival for men with an NBS1 mutation was 49%, compared with 72% for mutation-negative cases.

CONCLUSION

A mutation in NBS1 predisposes to aggressive prostate cancer. These data are relevant to the prospect of adapting personalised medicine to prostate cancer prevention and treatment.

A large germline deletion in the Chek2 kinase gene is associated with an increased risk of prostate cancer

BACKGROUND

Germline mutations in the Chek2 kinase gene (CHEK2) have been associated with a range of cancer types. Recently, a large deletion of exons 9 and 10 of CHEK2 was identified in several unrelated patients with breast cancer of Czech or Slovak origin. The geographical and ethnic extent of this founder allele has not yet been determined.

PARTICIPANTS AND METHODS

We assayed for the presence of this deletion, and of three other CHEK2 founder mutations, in 1864 patients with prostate cancer and 5496 controls from Poland.

RESULTS

The deletion was detected in 24 of 5496 (0.4%) controls from the general population, and is the most common CHEK2 truncating founder allele in Polish patients. The deletion was identified in 15 of 1864 (0.8%) men with unselected prostate cancer (OR 1.9; 95% CI 0.97 to 3.5; p = 0.09) and in 4 of 249 men with familial prostate cancer (OR 3.7; 95% CI 1.3 to 10.8; p = 0.03). These ORs were similar to those associated with the other truncating mutations (IVS2+1G-->A, 1100delC).

CONCLUSION

A large deletion of exons 9 and 10 of CHEK2 confers an increased risk of prostate cancer in Polish men. The del5395 founder deletion might be present in other Slavic populations, including Ukraine, Belarus, Russia, Baltic and Balkan countries. It will be of interest to see to what extent this deletion is responsible for the burden of prostate cancer in other populations.

NBS1 is a prostate cancer susceptibility gene

To evaluate whether an inactivating mutation in the gene for the Nijmegen breakage syndrome (NBS1) plays a role in the etiology of prostate cancer, we compared the prevalence of the 657del5 NBS1 founder allele in 56 patients with familial prostate cancer, 305 patients with nonfamilial prostate cancer, and 1500 control subjects from Poland. Loss of heterozygosity analysis also was performed on DNA samples isolated from 17 microdissected prostate cancers, including 8 from carriers of the 657del5 mutation. The NBS1 founder mutation was present in 5 of 56 (9%) patients with familial prostate cancer (odds ratio, 16; P < 0.0001), 7 of 305 (2.2%) patients with nonfamilial prostate cancer (odds ratio, 3.9; P = 0.01), and 9 of 1500 control subjects (0.6%). The wild-type NBS1 allele was lost in seven of eight prostate tumors from carriers of the 657del5 allele, but loss of heterozygosity was seen in only one of nine tumors from noncarriers (P = 0.003). These findings suggest that heterozygous carriers of the NBS1 founder mutation exhibit increased susceptibility to prostate cancer and that the cancers that develop in the prostates of carriers are functionally homozygous for the mutation.

Microangiographic imaging of the prostate

OBJECTIVE

To present the results of microangiography in visualizing prostatic microvascularization.

MATERIALS AND METHODS

A contrast medium was injected into the vessels of prostate specimens obtained during surgery, to fill small vessels; nine specimens were obtained after cystoprostatectomy and two after radical prostatectomy. Branches of prostatic or seminal vesicle arteries were used for the injection, the specimens then fixed in formalin, sectioned and X-rayed.

RESULTS

In five samples the quality of the images was sufficient to visualize small arteries; the remaining vessels were partially filled. The vascular map was compared with previous results from historadiographic studies.

CONCLUSIONS

Microangiographic imaging of prostate specimens provides a unique view of the angioarchitecture of the prostate and correlates closely with historadiographic studies. The correlation with other imaging methods, e.g. Doppler ultrasonography, needs further evaluation.

Usefulness of power Doppler ultrasonography in evaluating erectile dysfunction

OBJECTIVE

To evaluate deep penile arterial flow after an intracavernosal injection with papaverine in patients with erectile dysfunction (ED).

PATIENTS AND METHODS

Twenty patients with ED were evaluated using power Doppler ultrasonography with a linear probe (8 MHz). Diagnostic tests were undertaken after an intracavernosal injection with 40 mg papaverine. The peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistive index (RI) were analysed.

RESULTS

After injecting papaverine, seven patients had a normal erection and appropriate waveform patterns; their mean PSV was 30.7 cm/s, the EDV 4.42 cm/s and the RI 0.85. There was tumescence and elongation of the penis with no rigidity in eight patients; their mean PSV was 23.9 cm/s, the EDV 7.34 cm/s and the RI 0.72. There was no erection in five patients. The abnormal flow values showed insufficient arterial vessels in a quarter of the men, venous leakage in 15% and mixed ED in 20%.

CONCLUSION

The power Doppler technique allows the accurate location and evaluation of deep penile arteries. Vascular pathology may be differentiated after an intracavernosal injection with a vasomotor agent. Recognising the pathological pattern assists in choosing the best method of treatment.

Survival in patients with rare subtypes of renal cell carcinoma

OBJECTIVE

To evaluate the survival of patients with rare malignant histological subtypes of renal cancer.

PATIENTS AND METHODS

The Heidelberg classification of renal cell carcinoma (RCC) divides tumours into clear cell carcinoma (CCC), papillary cancer (PC), chromophobic cancer (ChC) and collecting duct carcinoma (CDC). Sarcomatoid tumours are in a different subgroup treated as a final stage of histological progression. Between 1990 and 1997, 319 nephrectomies were undertaken because of RCC in 317 patients. In 42 patients (13%) the pathological findings showed other than CCC; in 13 PC was confirmed histologically, in nine ChC, in 11 a mixed type of CCC and sarcomatoid type, in seven a sarcomatoid tumour and in four, CDC.

RESULTS

One patient of the 13 with PC and two of the nine with ChC died. The worst prognosis was in those with CDC, CCC-sarcomatoid and sarcomatoid tumours, as all these patients died.

CONCLUSION

The histopathological differentiation of RCC into subtypes gives additional useful prognostic information.

Monte carlo simulations of protein-like heteropolymers

Properties of a simple model of polypeptide chains were studied by the means of the Monte Carlo method. The chains were built on the (310) hybrid lattice. The residues interacted with long-range potential. There were two kinds of residues: hydrophobic and hydrophilic forming a typical helical pattern -HHPPHPP-. Short range potential was used to prefer helical conformations of the chain. It was found that at low temperatures the model chain formes dense and partially ordered structures (non-unique). The presence of the local potential led to an increase of helicity. The effect of the interplay between the two potentials was studied. After the collapse of the chain further annealing caused rearrangement of helical structures. Dynamic properties of the chain at low temperature depended strongly on the local chain ordering.

Monte carlo simulations of protein-like heteropolymers

Properties of a simple model of polypeptide chains were studied by the means of the Monte Carlo method. The chains were built on the (310) hybrid lattice. The residues interacted with long-range potential. There were two kinds of residues: hydrophobic and hydrophilic forming a typical helical pattern -HHPPHPP-. Short range potential was used to prefer helical conformations of the chain. It was found that at low temperatures the model chain formes dense and partially ordered structures (non-unique). The presence of the local potential led to an increase of helicity. The effect of the interplay between the two potentials was studied. After the collapse of the chain further annealing caused rearrangement of helical structures. Dynamic properties of the chain at low temperature depended strongly on the local chain ordering.

The effect of sequence patterns and local conformational preferences on the structure of collapsed polypeptide

We studied the structure of a polypeptide model by means of the Monte Carlo method. The model chain consisting of two kinds of residues (hydrophobic and hydrophilic) was confined on the (310) hybrid lattice. The residues interacted with the long-range contact potential. The short-range potential was also used by introducing the preferences of conformations corresponding to the helical structure. Simulations of the coil-to-globule collapse were done by an annealing process starting from high-temperature structures and then gradual cooling of the system. The parameters describing the behavior of the system were monitored. It has been found that in a case of a helical pattern -HHPPHPP- the collapsed chains consisted of helical fragments. The resulting structures were formed in such way that the polar residues were located in the outer shell of the molecule since the hydrophobic residues filled the inner part of molecule. The results showed that the proper balance between the magnitude of the potentials used in a model is important and its influence on final structures of molecules was discussed.

Giant neobladder calculus

An unusual case of a calculus in the ileal neobladder is presented. The size of the stone is exceptional in the urologic literature (940 g). Neocystolithotomy was performed, with full patient recovery.

Computer simulations of the properties of the alpha2, alpha2C, and alpha2D de novo designed helical proteins

Reduced lattice models of the three de novo designed helical proteins alpha2, alpha2C, and alpha2D were studied. Low temperature stable folds were obtained for all three proteins. In all cases, the lowest energy folds were four-helix bundles. The folding pathway is qualitatively the same for all proteins studied. The energies of various topologies are similar, especially for the alpha2 polypeptide. The simulated crossover from molten globule to native-like behavior is very similar to that seen in experimental studies. Simulations on a reduced protein model reproduce most of the experimental properties of the alpha2, alpha2C, and alpha2D proteins. Stable four-helix bundle structures were obtained, with increasing native-like behavior on-going from alpha2 to alpha2D that mimics experiment.

Computer simulations of de novo designed helical proteins

In the context of reduced protein models, Monte Carlo simulations of three de novo designed helical proteins (four-member helical bundle) were performed. At low temperatures, for all proteins under consideration, protein-like folds having different topologies were obtained from random starting conformations. These simulations are consistent with experimental evidence indicating that these de novo designed proteins have the features of a molten globule state. The results of Monte Carlo simulations suggest that these molecules adopt four-helix bundle topologies. They also give insight into the possible mechanism of folding and association, which occurs in these simulations by on-site assembly of the helices. The low-temperature conformations of all three sequences have the features of a molten globule state.

[Recording of nocturnal penile tumescence using the Rigiscan device]

Nocturnal spontaneous erections occur in healthy men being strictly correlated with paradoxal sleep phases with rapid eye movements (REM). There are simple methods of NPT recording like stamps test or erectiometers. Rigiscan-Plus device has 2 tensiometric loops and records all changes in tumescence and rigidity also as a response to visual or pharmacological stimulation. In this paper Rigiscan is presented and the role of rigidometry as an additional method in diagnostic of impotence is stressed.

[Unusual subclavian steal syndrome]

A case of unusual subclavian steal syndrome in a 50-years-old man without vertebro-basilar deficiency symptoms is reported. The lack of typical symptoms was caused by an uncommon collateral between the left vertebral and the left external carotid artery. The subclavian steal syndrome was revealed while diagnosing right hemiparesis which was the main cause of hospitalization.

Losses at 3p common deletion sites in subtypes of kidney tumours: histopathological correlations

Deletions of the short arm of chromosome 3 (3p) have been recognized as characteristic features of clear cell renal cell carcinomas (clear cell RCC). We analysed 55 clear-cell RCCs and 30 non-clear-cell kidney tumours (10 papillary and 7 chromophobic RCCs, 11 oncocytomas and 2 collecting duct carcinomas) in loss of heterozygosity (LOH) studies using microsatellite markers for previously observed regions of common deletions on 3p in kidney tumours (3p25, 3p21.3, 3p14.2 and 3p12-13). Alterations were found in all 55 cases of clear-cell RCCs at two to four of the 3p regions. Extensive losses were not found in non-clear-cell tumours except for collecting duct carcinomas; 1 of 10 papillary RCCs showed interstitial deletion limited to a single 3p21.3 locus. LOH analyses using microsatellite markers for regions of common deletions at 3p may be of value in differential diagnosis of kidney tumours.

Loss of heterozygosity at the familial RCC t(3;8) locus in most clear cell renal carcinomas

Previously, we had observed that more than 80% of clear cell renal carcinomas (RCCs) exhibited loss of heterozygosity (LOH) between the microsatellite markers D3S1285 (in 3p14.1) and D3S1295 (in 3p21.1), a region which includes the protein tyrosine phosphatase gamma locus (PTPRG locus, PTP gamma gene) and the 3p14.2 break of the familial RCC-associated translocation, t(3;8)(p14.2;q24), which has been hypothesized to affect expression of an RCC suppressor gene or oncogene. Using seven microsatellite markers and four markers derived from a PTPRG YAC contig, we have further delineated the 3p14.2 region of LOH in RCCs. Eighty-nine % of clear cell RCCs (31 of 35) showed a common region of loss between the D3S1481 and D3S1312 loci which flank the 3p14.2 t(3;8) translocation breakpoint and the PTP gamma gene. The PTP gamma gene occupies approximately 780 kilobase pairs between markers D3S1480 and D3S1312, with its currently defined 5' end greater than 200 kilobase pairs centromeric to the 3p14.2 translocation break. Although most of the RCCs with LOH between D3S1481 and D3S1312 loci have lost at least a portion of one PTP gamma allele, we have tested all known exons of the remaining PTP gamma gene in a number of the kidney tumors and have not observed mutations. Thus, there may be another gene in the vicinity of the 3p14.2 break that is important not only in the familial RCCs in the t(3;8) family but in the majority of clear cell RCCs.

Common regions of deletion in chromosome regions 3p12 and 3p14.2 in primary clear cell renal carcinomas

Nearly all clear cell renal cell carcinomas (RCCs) exhibit loss of alleles on the short arm of chromosome 3. Loss and mutation at the von Hippel-Lindau (VHL) gene at 3p25 probably occurs in most RCCs and, since the VHL gene was recently cloned, data on VHL involvement in RCCs is accumulating. However, the region 3p14-p12, a region that contains the familial RCC-associated t(3;8)(p14.2;q24) chromosome translocation and the small cell lung carcinoma-associated homozygous deletion at 3p13-12, has also been reported to exhibit allele loss in a large fraction of RCCs. In order to focus future studies on potential suppressor genes in the 3p14-p12 region, we have studied allele loss in 30 RCCs with 9 polymorphic simple sequence repeat markers spanning 3p21.1-p12. Partial losses in the 3p21-p12 region were observed, allowing determination of common regions of loss of heterozygosity overlap in 15 RCCs. Results suggested that most RCCs exhibit loss in a region which brackets the t(3;8) familial chromosome translocation at 3p14.2, and some show additional deletions within the U2020 small cell lung carcinoma deletion at 3p12.

[Symptomatic aneurysm of the abdominal aorta with coexistent horseshoe kidney]

A case of the 66 years old patient with an expanded, symptomatic abdominal aortic aneurysm has been reported. During an urgent operation a horseshoe kidney lying in the front of aneurysm was detected. The kidney was mobilised and good access to the aneurysm was achieved without division of the renal isthmus.

Dynamic Monte Carlo simulations of globular protein folding. Model studies of in vivo assembly of four helix bundles and four member beta-barrels

As part of an ongoing series of dynamic Monte Carlo simulations of globular protein folding, the nature of the folding pathway, of model four-member beta-barrels and four-helix bundles, under highly idealized conditions in vivo, has been examined. The ribosome is crudely modeled as an inert hard wall on to which the model protein chain is attached. Three cases are considered in detail. The first corresponds to post-translational assembly in which the fully synthesized chain is tethered to the wall and starts out under strongly denaturing conditions. The system is cooled down, and the chain is allowed to fold. Interestingly, the helical motif prefers to assemble parallel to the wall, whereas the beta-barrel, predominantly assembles with its principal axis perpendicular to the wall. In the former case, the dominant intermediate, the helical hairpin, is different from that in free solution, a three-helix bundle. The wall acts to reduce the expanse of configuration space that must be searched and aids in folding. Two situations that might lead to co-translational folding are also simulated. In the first case, to eliminate wall effects, the chain is slowly synthesized in free solution, and in the second case, it is slowly synthesized from the wall. In all cases, the chains are observed to fold post-translationally. While partially folded intermediates are observed during synthesis, they lack the stability to survive until chain synthesis is complete. The implications of these results for the folding in vivo of real protein chains is discussed, and a model of multiple domain protein folding is proposed.

Dynamic Monte Carlo simulations of globular protein folding/unfolding pathways. II. Alpha-helical motifs

Dynamic Monte Carlo simulations of the folding pathways of alpha-helical protein motifs have been undertaken in the context of a diamond lattice model of globular proteins. The first question addressed in the nature of the assembly process of an alpha-helical hairpin. While the hairpin could, in principle, be formed via the diffusion-collision-adhesion of isolated performed helices, this is not the dominant mechanism of assembly found in the simulations. Rather, the helices that form native hairpins are constructed on-site, with folding initiating at or near the turn in almost all cases. Next, the folding/unfolding pathways of four-helix bundles having tight bends and one and two long loops in the native state are explored. Once again, an on-site construction mechanism of folding obtains, with a hairpin forming first, followed by the formation of a three-helix bundle, and finally the fourth helix of the native bundle assembles. Unfolding is essentially the reverse of folding. A simplified analytic theory is developed that reproduces the equilibrium folding transitions obtained from the simulations remarkably well and, for the dominant folding pathway, correctly identifies the intermediates seen in the simulations. The analytic theory provides the free energy along the reaction co-ordinate and identifies the transition state for all three motifs as being quite close to the native state, with three of the four helices assembled, and approximately one turn of the fourth helix in place. The transition state is separated from the native conformation by a free-energy barrier of mainly energetic origin and from the denatured state by a barrier of mainly entropic origin. The general features of the folding pathway seen in all variants of the model four-helix bundles are similar to those observed in the folding of beta-barrel, Greek key proteins; this suggests that many of the qualitative aspects of folding are invariant to the particular native state topology and secondary structure.

Clonal diversity in human B cell lymphoma. I. Idiotypic and genetic analysis of lymphoma heterohybrids

Secretory heterohybrid clones from seven pristine human B cell lymphomas of diverse histologic types were established to investigate the question of tumor clonal diversity. We found that in six tumors, heterohybrid-derived Ig showed similar band patterns in IEF; families of anti-Id prepared from tumor Ig reacted uniformly with individual heterohybrids and original tumor; and the V gene loci displayed little variation on Southern analysis. In one patient who was followed with serial multiple site biopsies over a 14-mo period, clonal Id was preserved until the final stage of his disease, in spite of cytotoxic treatment. In a single follicular tumor (J.M.), each of the anti-Id reacted uniformly with the parent tumor and the individual heterohybrids, except that three of six clones failed to react with a single anti-Id family member. A Southern analysis of the VH gene locus revealed an identical gene rearrangement that was shared by the parent tumor and each heterohybrid. However, there was considerable heterogeneity of J.M. heterohybrid Ig in IEF gels, and we demonstrated the production of variant lambda L chains by the heterohybrid clones. One type of lambda L chain had a normal mobility in SDS-PAGE gels but larger lambda variants were produced by four of six heterohybrids. A Southern analysis of the VL gene displayed considerable variation in the type of lambda rearrangement present in the various heterohybrids, suggesting extensive diversity at the VL gene locus. In a second tumor (S.C.) that exhibited uniform anti-Id tumor reactivity we were also able to demonstrate the presence of a second minor tumor cell population (a biclonal tumor). Our data suggest that intraclonal VH variation may vary considerably with lymphoma subtype and mutagenic exposure and that an additional mechanism for generating spontaneous intraclonal heterogeneity is genetic variation at the VL locus.

Clonal diversity in human B cell lymphoma. I. Idiotypic and genetic analysis of lymphoma heterohybrids

Secretory heterohybrid clones from seven pristine human B cell lymphomas of diverse histologic types were established to investigate the question of tumor clonal diversity. We found that in six tumors, heterohybrid-derived Ig showed similar band patterns in IEF; families of anti-Id prepared from tumor Ig reacted uniformly with individual heterohybrids and original tumor; and the V gene loci displayed little variation on Southern analysis. In one patient who was followed with serial multiple site biopsies over a 14-mo period, clonal Id was preserved until the final stage of his disease, in spite of cytotoxic treatment. In a single follicular tumor (J.M.), each of the anti-Id reacted uniformly with the parent tumor and the individual heterohybrids, except that three of six clones failed to react with a single anti-Id family member. A Southern analysis of the VH gene locus revealed an identical gene rearrangement that was shared by the parent tumor and each heterohybrid. However, there was considerable heterogeneity of J.M. heterohybrid Ig in IEF gels, and we demonstrated the production of variant lambda L chains by the heterohybrid clones. One type of lambda L chain had a normal mobility in SDS-PAGE gels but larger lambda variants were produced by four of six heterohybrids. A Southern analysis of the VL gene displayed considerable variation in the type of lambda rearrangement present in the various heterohybrids, suggesting extensive diversity at the VL gene locus. In a second tumor (S.C.) that exhibited uniform anti-Id tumor reactivity we were also able to demonstrate the presence of a second minor tumor cell population (a biclonal tumor). Our data suggest that intraclonal VH variation may vary considerably with lymphoma subtype and mutagenic exposure and that an additional mechanism for generating spontaneous intraclonal heterogeneity is genetic variation at the VL locus.

Brain spectrin(240/235A): a novel astrocyte specific spectrin isoform

We have previously demonstrated the existence of two distinct isoforms of spectrin in mammalian brain (23). Brain spectrin(240/235) is found primarily in neuronal axons and presynaptic terminals, and brain spectrin(240/235E) is located in neuronal cell bodies, dendrites and postsynaptic terminals, and oligodendrocytes. These isoforms are thought to play important roles in controlling the early events of synaptic transmission, axonal transport of organelles and vesicles, and lateral mobility of integral membrane proteins. In this study, we have utilized a panel of monoclonal antibodies to identify a novel astrocyte specific isoform(240/235A) with subunits of 240 kDa and 235 kDa in a 1:1 ratio. Double label indirect immunofluorescence has indicated that brain spectrin (240/235A) is distinct from brain spectrin (240/235E). This novel isoform located in the soma and processes of astrocytes may play a role in actin-membrane attachment, cellular architecture, strengthening of the membrane fabric, and translocation of cytoplasmic organelles and vesicles.

Monte Carlo studies on equilibrium globular protein folding. III. The four helix bundle

The nature of the equilibrium conformational transition from the denatured state to a four-member alpha-helical bundle was studied employing a dynamic Monte Carlo algorithm in which the model protein chain was confined to a tetrahedral lattice. The model chain was allowed to hunt over all phase space, the target native state was not assumed a priori, and no site-specific interactions were introduced. The exterior vs the interior part of the protein is distinguished by the pattern of hydrophilic and hydrophobic interactions encoded into the primary sequence. The importance of a statistical preference for forming bends, as a function of bend location in the primary sequence, and helical wheel type cooperative interactions were examined, and the necessary conditions for collapse of the chain to the unique native structure were investigated. It was found that an amphipathic pattern of hydrophobic/hydrophilic interactions along with a statistical preference of the central residues for bend formation are sufficient to obtain the four-helix bundle. The transition to the native state has an all-or-none character.

Monte Carlo simulation of equilibrium globular protein folding: alpha-helical bundles with long loops

To help elucidate the general rules of globular protein folding, computer simulations of the conformational transition in model proteins having the left-handed, four-helix bundle motif in which the helices are joined by one or two long loops, as in apoferritin and somatotropin, respectively, have been undertaken. In the context of simple tetrahedral lattice protein models, these unique native helix bundle motifs can be obtained by a set of interactions similar to those found in previous simulations of the folding of four-member alpha-helical bundles with tight bends and beta-barrel proteins including the Greek key motif. The essential features sufficient to produce the four-helix bundle motif with long loops are as follows: (i) a general pattern of hydrophobic and hydrophilic type residues which differentiate the interior from the exterior of the molecule; (ii) the existence of hydrophilic regions in the amino acid sequence that, on the basis of short-range interactions, are indifferent to loop formation but that interact favorably with all the exterior residues of the helix bundle. Thus, these simulations indicate that, to reproduce all varieties of the left-handed four-helix bundle motif, site-specific interactions are not required.

Anatomical considerations of selective pudendal neurectomy

The pudendal nerve was examined in 100 cadavers of both sexes. Because of the variable number of trunks of the pudendal nerve, 5 types were distinguished: one-trunked; two-trunked, rectopudendal; two-trunked, pudendo-penile (or -clitoridal); three-trunked, recto-perineo-penile (or -clitoridal); four-trunked, recto-perineo-perineopenile (or -clitoridal). The authors' suggestions make it possible to perform selective pudendectomy, consisting in denervation of the sphincter urethrae muscle by neurectomy of the perineal branches of the pudendal nerve.

[Experiences with the Balser plate in dislocations of the acromioclavicular joint and lateral fractures of the clavicle]

Surgery of acromioclavicular luxations and lateral fractures of the clavicula with the Balser plate is described as a reliable low-complication method on the basis of the authors' own experiences in 13 patients. This treatment method offers significant advantages over the other conventional methods of surgery. Early mobilization of the patients is possible if exercise stability is present. Costly and complicated immobilization can be omitted, and so can reconstruction of the coracoclavicular ligaments or syndesmoplasty. The period of disability is shortened.

[Arterial vascularization of the human bulbo-uretral glands]

The study based on the dissection of 79 specimens of bulbo-urethral glands describes their arterial vascularisation. 1. The glands receive their main arterial vascularization from the artery of the bulb of the penis. The vessel reaches the surface of the gland from above and from both sides. 2. Supplementary sources of vascularization may take their origin from the int. pudendal artery, urethral art., perineal art., or an anastomosis between the cystic inferior art. and the pudendal int. artery. 3. The artery of the bulb of penis is variable. It may divide into two (often) or three (seldom) branches penetrating the bulb of the penis. One case with two arteries of the bulb (both from the pudendal int. artery), has been described. 4. The glandular arterioles ("short or intraglandular" ones) take their origine inside the gland (type I) or exist as supplementary arteries ("long or extracapsular" ones) branches from near arterial truncs (type II). If the gland is placed in the musculature of the uro-genital diaphragm and it is well separated from it by a connective-tissue capsule, the capsule receives its own ("capsular") branches, which are a supplementary source of vascularization for the gland (type III). 5. The existence of "long or extracapsular" branches is in connection with lobation of the gland. Every lobule receives its own branch from an "extracapsular" artery. 6. Only one slight right-left assymetry was observed.

[Effect of low-molecular dextran on leukergy and thrombergy in cases of cerebral infarct]

In cases of thrombotic cerebral infarction the leucergic and thrombergic tests were done on the 2nd and 3d days of the disease and after 48 hours from the first dextran loading. Fleck's test tube method was used in the leucergy test. The proportion of agglutinated platelets was calculated from a smear stained by Papanicolau method. The results were processed statistically. An inhibitory effect of dextran on aggregation of white blood cells and platelets was observed in the blood of patients with cerebral infarction. The inhibitory effects of dextran was greater in relation to aggregation of platelets than white blood cells. However, in our investigations the effect of this agent on both processes was transient.