The MoAb-VκIIIb Cross-Reactive Idiotope on A27a (Humkv325) Encoded Kappa Chains Maps to Framework Region 3

The monoclonal antibody MoAb-VκIIIb binds a cross-reactive idiotopic (CRI) determinant on light (L) chains encoded by the VκIIIb subgroup A27a (Humkv325) gene segment. The aim of this study was to localize the MoAb-VκIIIb CRI. Mutational analyses involving region exchanges between a CRI-positive VκIIIb chain and a CRI-negative Vκ1 chain indicate that the MoAb-VκIIIb CRI is located in framework region (FR) 3 of A27a (Humkv325) encoded L chains. CRI-positive kappa chains unpaired with a heavy (H) chain are reactive with MoAb-VκIIIb, indicating that the CRI is located on the kappa chain alone without involvement of H chain residues. Combinatorial antibodies composed of non-parental L and H chain pairings are reactive with MoAb-VκIIIb only when the L chain is A27a (Humkv325) encoded. The CRI, therefore, is not readily perturbed by H chain interactions. When the FR3 from a CRI-positive kappa chain replaced the FR3 in a CRI-negative lambda chain, the determinant was no longer detectable with MoAb-VκIIIb. It is possible, therefore, to exchange regions between kappa chains from different families and retain the CRI structure, however the determinant is lost when placed in a more foreign background such as a lambda chain. These data more precisely define the interaction between MoAb-VκIIIb and its CRI, and indicate that there are limits within which antibody FRs can be shuffled and still retain their native structural features.     

Diazepam in the Treatment of Dyspnoea in the 'Pink Puffer' Syndrome

Diazepam, in moderate doses, has been used in a placebo controlled,single blind study to treat dyspnoea in four patients severelydisabled from chronic airflow obstruction. The subjects hadthe ‘pink puffer syndrome’, usually associated withemphysema and were not hypercapnoeic nor severely hypoxic atrest. With diazepam, they experienced a striking reduction indyspnoea, and an improvement in effort tolerance; in additionthe slope of the ventilation/CO₂, response curve was rduced.There were no changes in resting blood gases. Psychiatric examinationat the end of the study did not reveal prominent anxiety, althoughthree patients were depressed. The use of diazepam to treatdyspnoea in this syndrome is safe in the absence of any acuteinfection.     

POLYMERIC 2-MERCAPTOPYRIDINE AND 2-MERCAPTO-NITROBENZENE DERIVATIVES: New Reagents for Peptide Synthesis

Insoluble 2-mercaptopyridine and 2-mercapto-nitrobenzene derivatives were prepared by modification of commercially available polystyrene. Applicability of these polymers as reagents for the thiolytic removal of the 2-nitrophenyl-sulphenyl amino-protecting group and as supports for preparation of polymeric active esters was evaluated. Polymeric 2-mercaptopyridine (PMP) was found efficient for both purposes. It was used in the stepwise synthesis of Leu-enkephalin via the polymeric reagent approach, serving as an Nps-cleaver. Polymeric esters derived from PMP and Boc-amino acids proved to be excellent acylators. Their usefulness is exemplified in the preparation of two dipeptides, which were produced rapidly and in high yields and purity.     

Increased Serum FSH Levels Correlated with Low and High Sperm Counts in Male Infertile Patients

Serum FSH, LH and testosterone were measured in 57 (42) normal men and in 80 male infertile patients. In the former, mean (x) FSH was found to be 2.5 ng/ml with a range (x +/- 2 SD) from 0.25 ng/ml to 5.3 ng/ml, mean LH was 2.2 ng/ml with a range from 0.5 ng/ml to 5.6 ng/ml, and mean testosterone was 540 ng/100 ml with a range from 190 mg/ml to 890 ng/100 ml. Immunoassayable FSH was found to be elevated in 17 out of 42 presumably infertile males with sperm counts below 20 million/ml, and in 5 out of 12 men with sperm counts above 120 million/ml. There was no correlation between testosterone and sperm number, motility, and seminal fructose content. The concurrence of depressed spermatogenesis and elevated FSH levels seems to be a relatively good indicator for the presence of organic disorders of the testis.     

Dynamic Beat-to-Beat QT-RR Relationship During Physiotherapy Effort in Elderly Patients Without Primary Heart Disease

The ECGs from 18 patients hospitalized in a rehabilitation setting, following surgery for hip fracture, were examined to characterize the dynamic behavior of uncorrected QT interval in relation to changing RR interval during physiotherapy effort. ECG waveforms were analyzed to extract beat-to-beat QT and RR intervals using a computerized ECG Analyzer (CEA-1100). The method of defining the QT and RR intervals is based on performing multiple cross-correlations that enable rejection of artifacts from the analysis. The relationship between the RR and QT intervals was found using the following general formula QTi = cRRi-1b. Linear regression was performed on the logarithms of QT and RR measurements obtained to estimate the constant (a = log c) and the slope (b) values, reflecting the dynamic change of QT during physiotherapy effort. Having these two values, the dynamic QT extrapolated to a heart period of 1 second (QTcd) was calculated. The results were compared to the conventional corrected static QT according to the Bazzet formula (QTcs). The mean values of constants (a = log c) and slopes (b) over all patients were found to be 1.61 +/- 0.23 and 0.33 +/- 0.08, respectively, giving a QT (ms) heart-period (ms) dynamic relation of QTi = 41 x RR(i-1)0.33. The correlation between the dynamic QT and the static QT intervals was not significant. The mean values of the QTcd and QTcs intervals were significantly different (392 +/- 25 ms vs 434 +/- 28 ms; P < 0.0001). This dynamic measurement method of QT intervals may provide additional information on normal and abnormal cardiac repolarization in health and disease, helping in the diagnosis of cardiac disorders and arrhythmia risk.     

Adult onset Mongolian spot

We report a case of adult onset, unilateral, progressive, grey-blue pigmentation on the back of an Asian male. Histology showed the pigmentation to be due to deep dermal melanocytes. The spectrum of clinical presentations of dermal melanocytosis is reviewed and the unique features of this case outlined.