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Biomedical subjects

M Cohen

Publications and source records attributed to M Cohen.

At least 919 records · Page 51Linked to original sources
PubMed1980

Thymic hormonal activity on human peripheral blood lymphocytes, in vitro. I. Reciprocal effect on T and B rosette formation.

One hour incubation with the thymic extract TP-1 induced reciprocal effect on B and T rosette formation in lymphocytes of human peripheral blood. The percentage of mouse erythrocyte rosette-forming cells among lymphocytes of chronic lymphatic leukaemia was decreased by TP-1 from 54.5% to 27.1% (P < 0.001). No such effect was observed in healthy adult or cord blood lymphocytes. On the other hand, the percentage of sheep erythrocyte rosette forming cells increased significantly after TP-1 treatment, but only under conditions of active rosette formation and not in the total rosette assay. This increase was highly significant in three conditions with relative deficiency of cell-mediated immunity: newborns (17.1 to 28.3%), cancer patients (24.5 to 31.7%) and patients with lepromatous leprosy (19.8 to 31.8%). Only a small increase was noticed in healthy adults. A similarly prepared spleen extract was not active in either B or T rosette assays.

Adult↗
PubMed1980

Postfracture linear bone growth in rats: a diurnal rhythm.

The effect of fracture of the tibia on the subsequent overgrowth of the femur in the injured limb has been studied in ad lib, -fed rats. The thrust of these studies was to determine if the time in the body rhythm (diurnal) when injury was sustained could influence the rate of postfracture linear bone growth. Accordingly, different groups of young rats were subjected to tibial fracture at one of 4 times in a 24 hour day (6 hours apart), and a ratio of femur lengths (injured left side/intact right side) in each group was calculated 30 days thereafter. The data indicated that midday was the only time when tibial fracture elicited significant femoral overgrowth. At this time, the femur length differential in the fractured rats was small (0.52 mm), but it was significantly greater than that observed in intact control rats. The diurnal response was not present in fractured hypophysectomized rats, nor could it be detected in normal rats by measuring the thicknesses of the growth cartilages from the intact and fractured tibias. However, in 2 separate studies, the patterns of radiostrontium retention in the tibias and in the femurs confirmed that midday was the time in the rat body rhythm when processes of ossification in the epiphyses and in the remodeling fracture callus proceeded most actively. The 24-hour retention of 85Sr in the fractured tibias was greater than that in the intact tibias (5 days postfracture), but the 5-day retention of isotope in the femurs on the side of tibial fracture (30 day postfracture) was significantly less than that of the bone in the uninjured limb. The skeletal responses to fracture are not limited to the injured element; the magnitude of the responses both in injured and intact bones of a limb have a diurnal component.

Animals↗
PubMed1979

Pseudomonas sternotomy wound infection and sternal osteomyelitis. Complications after open heart surgery.

Pseudomonas aeruginosa sternotomy wound infections occurred in five patients who underwent open heart surgery. The initial isolate in each case was from a mediastinal chest tube routinely cultured on removal. Soft-tissue infection developed in two patients, and sternal osteomyelitis developed in three patients. Pseudomonas-typing studies showed a correlation between five isolates from chest-tube suction pumps used postoperatively and the wound isolates. Analysis of antibiograms of Pseudomonas wound isolates from the cardiac surgery ward from 1975 to 1977 showed eight of 15 with the same antibiogram as the sternotomy pathogens, compared with two of 13 isolates from other wards.

Cardiac Surgical Procedures↗
PubMed1979

Children's comprehension of relative clauses.

A review of the literature on children's use of relative clause constructions reveals many contradictory findings. The suggestion is that some studies fail to take into account the two factors of embeddedness (role of complex noun phrase within the sentence) and focus (role of head noun in the relative clause). The experiment reported here attempted to reconcile the disparate findings and extend the range of constructions examined. 114 children between the ages of 3 and 7 served as subjects in a test of comprehension using an act-out procedure of 9 different relative clause sentences that exhaust the possible combinations of 3 roles of the complex noun phrase in the sentence and 3 roles that the head noun plays within the relative clause (in each case, subject, direct object, and indirect object). All constructions were understood better with increasing age of the children; sex and sentence set were nonsignificant variables. The results reveal a difficulty in ordering of the 9 types of construction that is in keeping with a prediction based on surface structure processing strategies.

Age Factors↗
PubMed1979

Nitrofurantoin: another cause of drug-induced chronic active hepatitis? A report of a patient with HLA-B8 antigen.

Nitrofurantoin, an agent used extensively in chronic urinary tract infections, is rarely incriminated as a hepatotoxin. In this 27 year old women chronic active hepatitis first developed during exposures to nitrofurantoin, and she later suffered exacerbations. Earlier reported cases are reviewed which describe a spectrum of hepatotoxic reactions. This patient has HLA-B8, an antigen associated with autoimmune forms of chronic active hepatitis. It is postulated that the antigen may be associated with liver injury initiated by drugs such as nitrofurantoin.

Adult↗
PubMed1979

Antibody-dependent cellular cytotoxicity to human colon-tumour cells. I. Lack of tumour specificity in a population study.

The humoral and cellular components of the antibody-dependent cellular cytotoxicity (ADCC) against allogeneic human colonic tumour cell lines were evaluated. The 2 colon cell lines used in this study (HT-29 and ACC-20) were found by immunofluorescence to have carcinoembryonic antigen (CEA) on their surface, and to become sensitive to the lytic effect of unstimulated lymphocytes after coating with heterologous anti-CEA. This reaction was used to evaluate the ADCC activity of mononuclear cells from the peripheral blood of patients with gastrointestinal cancer (mostly local extensive colo-rectal). Remarkable variability was found in the lytic capability (2-50% specific lysis) of both cancer and non-cancer mononuclear cells, with no significant difference between them. Sera from 127 cancer patients and 91 non-cancer patients were tested, using the reaction with heterologous anti-CEA as positive control and as a reference point. In 46 cases (21%) the sera were reactive in this system, and 43 of them were of Blood Group O. However, there was no difference between the cancer patients and the normal controls. The antigenic determinant involved in this reaction is not the Blood Group A specificity but, most probably, a polypeptide common to CEA and A (as shown in the following publication). In addition, trials for the elimination of the non-tumour-specific reaction, by absorption or inhibition, failed to disclose a tumour-specific one. The value of the ADCC assay in monitoring human tumour immunity, and possible ways of eliminating reactivity to normal antigens in this system, are discussed in the light of these findings.

ABO Blood-Group System↗
PubMed1979

Antibody-dependent cellular cytotoxicity to human colon-tumour cells. II. Analysis of the antigens involved.

The relationship between carcinoembryonic antigen (CEA) and A antigenic determinants on the cell surface of colon-tumour cells was studied by the ADCC assay. Antiserum prepared in 2 rabbits to an undecapeptide analogous to the amino terminal of CEA(1-11) was found by us either to participate in (Rabbit 2) or specifically inhibit (Rabbit 1) ADCC. The binding spectra of these two antisera and of antiserum to the whole CEA molecule were similar. All of them react with A and non-A colon-tumour cells as well as red blood cells of Type A (RBC-A) and their activity was completely absorbed on RBC-A but not on B or O. O-type, ADCC-reactive human sera always react with A-type colon-tumour cells and RBC-A, and some of them with non-A colon-tumour cells also. The degree of inhibition of their reactivity by anti-CEA(1-11) R1 varied between sera, from none to almost a complete inhibition, and is not related to whether the serum is of cancer or non-cancer origin. Non-reactive O-type sera contain anti-A activity demonstrable by haemagglutination and immunofluorescence. However, they cannot participate in ADCC reaction nor inhibit it. The sera, which contain lymphocyte-dependent antibody to A-type colon-tumour cells, lysed RBC-A, without the addition of lymphocytes or complement, in an immunologically specific way. It is concluded that the reactivity seen in our ADCC system is related to a determinant common to A and CEA (and maybe to other normal cross-reacting antigens) which most probably resides in the amino terminal part of these molecules. This determinant elicits the production of lymphocyte-dependent antibodies in about 50% of people with blood group O. Thus, the amino terminal part of CEA is not a tumour-specific part of the CEA molecule. No specific anti-tumour activity was found in patients' serum by this method, and claims for its demonstration by other methods may well be related to the non-specific activity observed here.

ABO Blood-Group System↗
PubMed1979

A single-bedtime-dose self-medication system.

A medication system in use at the Florida Mental Health Institute is based on the unit-dose procedure and weekly reviews of patients' medications. The program is aimed at reducing the use of polypharmacy and of concentrates and stabilizing patients on a single daily bedtime dose of medication. Once patients are stabilized on a single dose, they are trained by the nurses and through a drug group to manage their medications independently after discharge. The system has produced savings of up to 90 per cent of medication costs per patient and is gaining acceptance in other mental health facilities in the state. The authors believe it has the potential for even greater therapeutic and financial benefits by reducing the recidivism that occurs when discharged patients discontinue their drugs.

Adult↗
PubMed1979

A retrospective study of hearing impairment in three groups of cleft palate patients.

Three groups of cleft palate patients were evaluated for hearing impairment and secretory otitis at age five to determine the effect of myringotomy and tube placement. Each group consisted of 23 patients (46 ears). Hearing levels and otoscopic evaluations were obtained retrospectively from medical records. Group I had had no myringotomies. Group II had myringotomies after the initial palate closure and only when deemed necessary. Group III had had myringotomies at the initial palate closure and subsequently as needed. Optimal timing for myringotomy in cleft palate patients to maximize hearing at school age could not be determined. The need for myringotomy must be determined by clinical judgement on an individual basis.

Child, Preschool↗
PubMed1979

The types of hearing loss and ear pathology noted in screening craniofacial patients.

Seventy patients who underwent craniofacial reconstruction were screened by otological and audiological examinations. Thirty-seven patients had visible ear pathology, thirty-six had conductive hearing impairments. No sensorineural losses were detected. The high incidence of otological pathology in craniofacial patients emphasizes the importance of multi-disciplinary care. Otological rehabilitation should be integrated into the treatment plan to provide maximum function throughout the period of craniofacial reconstruction. Suggestions are made to facilitate communication in the immediate post operative period.

Adolescent↗