The molecular genetics of head development in Drosophila melanogaster.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to R Finkelstein.
Explore the source record for details and available documents.
In the Drosophila embryo, cell fate along the anterior-posterior axis is determined by maternally expressed genes. The activity of the bicoid (bcd) gene is required for the development of larval head and thoracic structures, and that of maternal torso (tor) for the development of the unsegmented region of the head (acron). In contrast to the case of thoracic and abdominal segmentation, the hierarchy of zygotically expressed genes controlling head development has not been clearly defined. The bcd protein, which is expressed in a gradient, activates zygotic expression of the gap gene hunchback (hb), but hb alone is not sufficient to specify head development. Driever et al. proposed that at least one other bcd-activated gene controls the development of head regions anterior to the hb domain. We report here that the homeobox gene orthodenticle (otd), which is involved in head development, could be such a gene. We also show that otd expression responds to the activity of the maternal tor gene at the anterior pole of the embryo.
Explore the source record for details and available documents.
The orthodenticle (otd) locus of Drosophila is required for embryonic development, and null mutations of otd cause defects in head development and segmental patterning. We show here that otd is necessary for the formation of the embryonic central nervous system (CNS). otd mutations result in the formation of an abnormal neuropil and in the disappearance of identified neurons associated with the midline of the CNS. In addition, otd is allelic to ocelliless (oc), a mutation that causes the deletion of the ocelli of the adult fly. We have identified a transcription unit corresponding to the otd locus and find that it is expressed early in a stripe near the anterior pole of the cellular blastoderm and later in the region of the CNS from which these neurons normally arise. The predicted otd protein contains a well-conserved homeo domain and is therefore likely to be a transcriptional regulator involved in specifying cell fate both in the embryonic CNS and in the ocelli.
Pyomyositis of the pectoralis major was diagnosed in a 79-year-old man and Staphylococcus aureus was grown from pus drained from the infected muscle. Bacteremia and overwhelming sepsis accompanied the infection, and the patient died despite early diagnosis, combined chemotherapy and surgical drainage. The incidence of pyomyositis has been increasing lately in temperate climates. To our knowledge, this is the first report of nontropical pyomyositis in Israel.
Explore the source record for details and available documents.
Between July 1984 and August 1985, 200 cases of methicillin-resistant Staphylococcus aureus (MRSA) occurred in a large, tertiary care, medical school-affiliated hospital. During this period, a limited outbreak, causing serious infections, was identified in the Intensive Care Unit and was contained by appropriate infection control measures. Bacteriophage typing and surveillance cultures failed to identify a common or single source of dissemination of these strains. It appears that MRSA strains have emerged in Israel as endemic pathogens in hospitals, capable of causing serious nosocomial outbreaks.
The occurrence of nine cases of Pseudomonas septic arthritis and osteomyelitis within a 12-month period may be considered an uncommon experience even in a large, tertiary referral center. These cases are reported here and the various clinical patterns and therapeutic implications associated with Pseudomonas bone infections are discussed. Epidemiologic serotyping of the isolated strains indicated that they do not represent a single nosocomial outbreak.
A major outbreak of waterborne typhoid fever involving 77 verified cases occurred in 1985 in a large suburban area of Haifa, Israel. The authors summarize the clinical, microbiologic, and therapeutic aspects of these patients. Fever, usually higher than 39 degrees C, was the hallmark of the disease. Other manifestations of typhoid, although relatively frequent, are presented as part of a mild nonspecific symptom complex, often found only in the prodromal period. An elevated level of serum glutamic-oxaloacetic transaminase (mean, 81 IU/ml) was the most characteristic laboratory abnormality, occurring in 94% of the patients. Blood cultures were positive in 46 of the 50 patients (92%), and were not affected by prior outpatient antibiotic therapy. The first blood culture was diagnostic in 93% of the cases. Although fever tended to disappear more rapidly among patients receiving ampicillin than among those treated with chloramphenicol, results of therapy were similar in both groups. Nevertheless, the relapse rate of 36% among 25 chloramphenicol-treated patients was significantly higher than the 9% noted among 22 patients treated with ampicillin. Except for one case of hemolytic anemia, serious complications were conspicuously absent, and outcomes were uniformly favorable.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Sphenoid sinusitis is a frequently misdiagnosed infection. Delay in recognition and treatment carries a very poor prognosis. An unusual case of sphenoid sinusitis mimicking a syndrome of chronic meningitis is presented. This case emphasizes the diagnostic challenge of sphenoid sinusitis which may present only through its complications.
In order to quantify information provided by echocardiography for residents in internal medicine and for cardiologists, 150 selected patients were studied by echocardiography, and the ultrasonic diagnosis was compared with the clinical evaluation. Among 144 patients with adequate visualization of the heart, echocardiography provided findings that were totally unexpected to the residents in 13 (9%) and to the cardiologist in 9 (6%) patients. Echocardiography also provided information relevant to the management of the patient in another one-third of the cases. Both the residents and the cardiologist were able to correctly predict the cause of cardiomegaly and the mechanism of heart failure in most patients presenting with these findings. Despite the introduction of cross-sectional echocardiography, the amount of information contributed by echocardiography has not increased since 1978, when a similar study was performed at our institution. This may reflect increased clinical skill among residents, probably due to long-term exposure to echocardiography during their training.
Explore the source record for details and available documents.
Explore the source record for details and available documents.