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PubMed1977

Ovulation induction with human menopausal gonadotrophins: an evaluation of a variable daily dosage regimen.

Human menopausal gonadotrophins (HMG) were used together with human chorionic gonadotrophin (HCG) in 19 women and 39 treatment cycles in an attempt to induce ovulation. Daily 24 hours urinary total estrogen excretion rates were measured and HMG daily dosage was varied according to levels obtained. HCG injections were timed to coincide with an estimated urinary total estrogen excretion rate of 100-150 g per 24 hours. Thirty-one ovulatory cycles occurred (79%) and there were nine pregnancies (23%) of which five were multiple. Eleven cycles were complicated by hyperstimulation (25.6%) of which six were severe. The variable HMG dosage regimen was found to offer no advantages when compared with our standard daily dosage regimen. A rapid rise of estrogen excretion occurred in over 80% of hyperstimulation cycles, including all severe ones, and it was found that this rise could occur after the last dosage of HMG had been given. Because of this, it is proposed that HCG injections be delayed until 48 hours after the last injection of HMG. The finding of a value for the last available 24 hour urinary total estrogen excretion of less than 150 microgram can be taken as an indicator that hyperstimulation is unlikely to occur, and that HCG can safely be given. No indication was found that such a procedure would diminish ovulation or pregnancy rates.

Chorionic Gonadotropin↗
PubMed1979

[The primary structure of the Bence-Jones protein Kue. The amino acid sequence of the variable part of a human L-chain of the kappa-type (author's transl)].

The complete primary structure of the variable region of Bence-Jones protein Kue was elucitated with the aid of a few tryptic peptides, as well as one chymotryptic and one BNPS-scatol fragment. As a consequence of the evident homologies to other proteins this protein belongs to subgroup k/I. Protein Kue has some amino acid exchanges in certain positions in common with other proteins, probably giving rise to a new sub-subgroup. The constant region shows no amino acid exchanges in comparison with other human kappa L-chains. With valine covering position 191, protein Kue should be grouped per definition as an allotype Km (3).

Amino Acid Sequence↗
PubMed1976

Complete amino acid sequence of the variable domains of two human IgM anti-gamma globulins (Lay/Pom) with shared idiotypic specificities.

On the basis of extensive shared idiotypic specificities, two human IgM anti-gamma-globulins (Lay/Pom) were selected for complete amino acid sequence analysis of their variable domains. Previous studies on the variable regions of the heavy chains of these proteins had shown but eight amino acid differences, only one of which was within a complementarity-determining hypervariable region. The complete amino acid sequence of the variable regions of the light chains of these two proteins is the subject of this report. Protein Lay is a typical VchiI protein with only five 'framework' differences when compared with protein Roy. Protein Pom is best classified as a VchiII, but in the 'framework' there are 16 differences between it and protein Ti. Although there are extensive differences in the first hypervariable region, the second and third light-chain hypervariable regions have an identical sequence. The finding of two identical light-chain and two identical heavy-chain hypervariable regions in these two proteins, which were selected on the basis of their combining specificities and their idiotypic cross-reactions, strongly implicates hypervariable regions in the constitution of the idiotypic determinants and the antibody combining site. Additionally, the finding of identical hypervariable regions in light chains of different V-region subgroups fulfills a prediction of the gene-interaction concept of antibody variability.

Amino Acid Sequence↗
PubMed1978

Hv(1), a variable-region genetic marker of human immunoglobulin heavy chains.

A new antigenic determinant was discovered with a hemagglutination-inhibition assay system. Designated Hv(1), it is located in the variable region of human immunoglobulin heavy chains of the G, M, and A classes. Pedigree and population analyses suggest that it has an autosomal dominant mode of inheritance. This represents the first description of an allotypic determinant in the variable region of human immunoglobulins.

Binding Sites, Antibody↗
PubMed1975

Distribution and association of heavy and light chain variable region subgroups among human IgA immunoglobulins.

A series of randomly selected human IgA myeloma proteins were examined for the presence of the VHIII subgroup as defined by the possession of an unblocked amino terminal amino acid and characteristic linked residues along the heavy chain. Blocked heavy chains were classified as VHB proteins. The data showed that 20 of 30 such random alpha chains (67%) were classifiable as members of the VHIII subgroup. Similarly, 75% of heavy chains isolated from pools of normal serum IgA contained a VHIII variable region. The pattern stands in marked contrast to the situation in human IgG proteins where approximately 20% of heavy chains from both pools and myeloma proteins are VHIII. There was thus a clear divergence of the pattern of variable region: constant region association between these two classes of immunoglobulin. Some more limited data were obtainable for the light chains of the IgA myeloma proteins. Certain predilections for light chain subgroup:heavy chain subgroup (VHIII or VHB) associations were discernable, but more data are required for definite conclusions. Overall, this study suggests that although the pool of available variable region sequences is indeed shared among human IgA and IgG proteins, the partitioning is not exactly equivalent between the two immunoglobulin classes. The pattern is particularly apparent at present for the VHIII subgroup which comprises approximately 70% of human alpha chains and only about 20% of human gamma chains.

Amino Acid Sequence↗
PubMed1979

Variability of laminar patterns in the human lateral geniculate nucleus.

The structure of the human lateral geniculate nucleus has been studied on serial Nissl stained sections from 57 human brains. Most of the brains were from neurologically normal individuals and were obtained during routine autopsy procedures. The laminar arrangement within the human nucleus is surprisingly variable. It is always possible to recognize a small segment with two layers (the monocular segment), one with four layers and one with six layers. Often an 8-layered segment can also be seen. The posterior half of the nucleus, within which central vision is represented, is made up mainly of six layers, and is the least variable part of the nucleus. Here the layers lie roughly parallel to each other. In the anterior half of the nucleus the laminar arrangement is more variable, and the layers often form complex and irregular interdigitations with each other. The 8-layered segment varies greatly in size and may be absent. It generally lies at the edge of the 4-layered segment not, as might have been expected, within the borders of the 6-layered segment. In many parts of the nucleus nerve cells are organized in short rows that run perpendicular to the layers; also, individual nerve cells are elongated in this direction. This neuronal orientation follows the lines of projection that are defined by the borders of a zone of retrograde degeneration, and also corresponds to the orientation of a cellular discontinuity that probably is the geniculate representation of the blind spot. Thus, we conclude that the neuronal orientation indicates the lines of projection within the nucleus.

Adolescent↗
PubMed1979

Amino acid sequence of the heavy-chain variable region of the crystallizable human myeloma protein Dob.

The amino acid sequence of the heavy-chain variable region of the crystallizable human myeloma protein Dob has been determined. This protein has previously been shown to have a deletion in the hinge region [Lopes, A. D., & Steiner, L. A. (1973) Fed. Proc., Fed. Am. Soc. Exp. Biol. 32, 1003; Steiner, L. A., & Lopes, A. D. (1979) Biochemistry (preceding paper in this issue)]. The complete sequence was established by analysis, in the automated sequenator, of the intact Fd' piece and of three large overlapping fragments prepared from Fd' by digestion with cyanogen bromide, by tryptic digestion of the citraconylated Fd', and by cleavage with hydroxylamine. Portions of the sequence were confirmed by examination of the amino acid composition and the partial sequence of a variety of small peptides obtained by enzymatic degradation. The Dob heavy-chain variable region appears to belong to the VHIII subgroup, but there are several unusual substitutions. Residue 45 in the Dob sequence is proline, although all other known heavy-chain sequences in man, mouse, rabbit, and guinea pig have leucine at this position. Positions 10 (aspartic acid), 68 (alanine), and 82 (leucine) in the Dob sequence are also atypical. There is no deleted segment in the variable region of the Dob heavy chain nor any abnormality in the variable-constant joining region. The hinge-region deletion appears to be the only gross structural anomaly in the Dob heavy chain.

Amino Acid Sequence↗
PubMed1977

The human Y chromosome: its routine identification and variability.

Different criteria for identifying the human Y chromosome using only conventional staining techniques were evaluated and a procedure based on three of them was developed. It leads to correct identification in 93% of cells even without resorting to differences in size between the Y and the other G chromosomes. The variability in size of the human Y chromosome was assessed in a random group of White men. It was found to be significantly greater than that of all other chromosomes in the karyotype when the comparisons were made in such a way as to avoid the size-dependent component of variation.

Analysis of Variance↗
PubMedDate not supplied

[Intraspecies variability of the normal human karyotype].

On the basis of data from literature the number of different normal structural variants of each human chromosome is calculated. Assuming independent combination of chromosome variants, the number of possible combinations of variants of all 22 pairs of autosomes and the probability of an individual to be hormozygous for the most frequent variants of all the autosome pairs simultaneously are estimated. The results obtained show that nearly each individual possesses a unique karyotype--a unique set of properties of chromosome heterochromatic regions.

Chromosomes, Human↗
PubMed1976

Variable adherence to normal human urinary-tract epithelial cells of Escherichia coli strains associated with various forms of urinary-tract infection.

The ability to become attached to normal epithelial cells from the urinary tract was much greater in Escherichia coli bacteria isolated from the urine of patients with acute symptomatic pyelonephritis or cystitis than in those isolated from the urine of patients with asymptomatic bacteriuria. Attachment of the bacteria could be prevented by incubation in urine containing antibodies against the strain tested. The ability to attach to uroepithelial cells might be a virulence factor for E. coli strains which cause symptomatic urinary-tract infection.

Acute Disease↗
PubMedDate not supplied

[Antigenic determinants of human immunoglobulin light and heavy chain variable regions. Comparison with animal species].

An antigenic analysis of human heavy and light chain variable region subgroups has been done on different animal species, by means of heterologous specific antisera using a hemagglutination-inhibition procedure. Excepted in lemur sera, where Vkappa III and Vlambda III are the only variable antigenic determinants found, all VL antigenic determinants tested were shown to be present in primates. In other mammals (carnivores, some rodents, some artiodactyls) several VL antigenic subgroup determinant were detected while others were not. No VL antigenic determinant was found in other classes studied. The VH III subgroup antigenic determinant was found among all primates, some mammals and avains. The results suggest that there has been more preservation in the variable region of immunoglobulin chains, and particularly VH III chain, than in the constant region of immuoglobulin molecule.

Animals↗
PubMedDate not supplied

Heavy and light chain variable region subgroups: antigenic analysis among human monoclonal immunoglobulins.

An antigenic analysis of human heavy and light chain variable region subgroups has been possible by means of heterologous specific antisera using a hemagglutination-inhibition procedure. The specificity of antisera had been shown to be directed against antigenic determinants of VkappaI, VkappaII, VkappaIII, VlambdaI, VlambdaII, VlambdaIII and VHIII by means of chemically subgrouped proteins. A series of IgG, IgA, IgM and IgD were examined for the presence of a VHIII variable region subgroup antigenic determinant. The data showed that 50% IgG, 62% IgA, 55% IgM, 45% IgD were positive for VHIII antigenic determinant. NH2 terminus blocked monoclonal immunoglobulin belonging to the VHIII subgroup were found, increasing incidence of this subgroup among IgG. A preferential association of VHIII antigenic determinant with IgG1, IgG3 subclasses was observed among IgG myeloma proteins while the preferential association was only observed with IgG1 subclass when anti-Rh antibodies were considered. Among 53 IgG of kappa type 20 (37%) kappaI, 30 (56%) kappaII, 3 (5%) kappaIII subgroups were found and among 42 IgG of lambda type 13 (31%) lambdaI, 13 (31%) lambdaII and 16 (38%) lambdaIII were observed. Although numbers are limited in each group for conclusions a study of VHIII and non VHIII antigenic subgroup determinant with respect to the light chain subgroups is given. The non-allelic behaviour of this VHIII antigenic determinant was observed. Preliminary data on the presence of these human antigenic determinants among different animals species were given.

Animals↗
PubMed1979

Temperature and acid-base status of human blood at constant and variable total CO2 content.

The influence of temperature on the acid-base status of normal human blood was studied in closed systems (constant CCO2) and open systems (variable CCO2). pH-T coefficients of true plasma and erythrocytes in closed systems were similar to coefficients for water (dpH/dT = -0.017 U/degrees C at 25 degrees C). Between 26 degrees C and 42 degrees C there was no significant variation in the relative alkalinities [OH-]/[H+], the charge state of proteins in plasma and erythrocytes or the proton Donnan ration. The equations established enabled calculation of the pH of true plasma and erythrocytes and of blood PCO2 and temperature, using only one of these four parameters. Under open-system conditions, temperature was shown to cause a rise in the apparent buffer power of whole blood non-bicarbonate systems (28.8 and 34.8 mM.l-1.u-1 at 26 degrees C and 42 degrees C respectively). These results show (1) that erythrocytes in closed systems seem very well able to maintain proton distribution regardless of temperature fluctuations and (2) when blood temperature rises, it cannot be excluded that vital organs are better protected against respiratory disturbances.

Acid-Base Equilibrium↗
PubMed1978

Trace-metal concentrations in normal human liver: methods to cope with marked variability.

Concentrations of trace elements in human tissues characteristically vary widely, and the distributions of most concentrations are skewed to the right. Examination of some of the factors which contribute to the marked variability and skewness of the concentrations revealed that: (1) distributions of concentrations are satisfactorily normal (Gaussian) after logarithmic transformation, (2) ash weight is the best frame of reference in which to report results, (3) the distributions of metal concentrations are not further normalized by adjustments which assume that tissue lipid or collagen contains a fixed fraction of the metal found in the parenchyma, and (4) the choice of sample site within the liver is of minimal significance.

Adult↗
PubMed1976

Antigenic determinants of heavy chain variable regions: immumological typing of the human immunoglobulin VHIII subgroup.

An antigenic determinant of the VHIII variable region subgroup was defined by means of a heterologous specific antiserum using a hemagglutination inhibition procedure. The specificity of this antiserum was established in inhibition experiments with proteins either of known primary structure or belonging to a definite VH subgroup. A series of IgG, IgA, IgM and IgD monoclonal proteins was examined for the presence of this VHIII subgroup antigenic determinant. The data showed that 50% of the IgG, 62% of the IgA, 55% of the IgM and 41% of the IgD were VHIII-positive, and that certain "blocked" monoclonal immunoglobulins belonged to this subgroup. A preferential association of the VHIII antigenic determinant with the IgG1 and IgG3 subclasses was observed among IgG myeloma proteins while the preferential association was only observed with the IgG1 subclass when anti-Rh antibodies were studied. The VHIII subgroup exhibited nonallelic behavior.

Epitopes↗
PubMed1978

Prematurity and perinatal mortality in the Rhesus (Macaca mulatta): relationship to birth weight and gestational age.

While the relative influence of birth weight and gestational age in determining perinatal mortality has not been definitively established, it has been assumed that birth weight makes the predominant contribution to perinatal mortality. The joint effects of birth weight and gestational age were examined by analyzing approximately 2,500 births from timed pregnancies in two rhesus (Macaca mulatta) breeding colonies. Perinatal events in the rhesus are described and shown to be similar to the human. The results demonstrate that gestational age is as important as birth weight in determining perinatal mortality. Since the degree of accuracy in the estimation of rhesus gestational age was much greater than is usually attained in human studies, the estimation of gestational age from the last menses may be too crude to determine the importance of this variable in human perinatal mortality.

Animals↗