The effects of streptozotocin-induced (STZ) diabetes on neuroendocrine and sexual function were evaluated in adult male rats. Adult male rats were injected with STZ (50 mg/kg) or vehicle and tested for copulatory behavior 7, 14, and 21 days later. The rats were killed 1 month after STZ or vehicle treatment for measurement of plasma hormone levels, hypothalamic catecholamine turnover, LHRH content, and in vitro pituitary function. The STZ rats showed significant deficits in mount, intromission, and ejaculatory behaviors. Plasma levels of testosterone, LH, FSH, and PRL were all significantly reduced in the STZ compared to the control rats, but in vitro LH secretion was enhanced after STZ treatment. In vitro PRL secretion and the inhibitory response to dopamine did not differ between the two groups. The levels of LHRH were reduced in the medial basal hypothalamus (MBH), but LHRH levels in the median eminence (ME) and anterior hypothalamus (AH) were unchanged after STZ treatment. Norepinephrine turnover was reduced in the ME, MBH, and AH of the STZ rats, while dopamine turnover was unchanged in the ME, increased in the MBH, and reduced in the AH of the STZ rats compared to those in the vehicle-treated controls. These results suggest that changes in pituitary and testicular function in rats made diabetic by STZ treatment are secondary to changes in hypothalamic catecholamine metabolism. Changes in copulatory behavior could be due to both reductions in plasma testosterone levels as well as changes in central neurotransmitter metabolism.

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BackgroundRespiratory illness is a leading cause of morbidity in adults and the number one cause of mortality in children, yet billions of people lack access to medical imaging to assist in its diagnosis. Although ultrasound is highly sensitive and specific for respiratory illness such as pneumonia, its deployment is limited by a lack of sonographers. As a solution, we tested a standardised lung ultrasound volume sweep imaging (VSI) protocol based solely on external body landmarks performed by individuals without prior ultrasound experience after brief training. Each step in the VSI protocol is saved as a video clip for later interpretation by a specialist.MethodsDyspneic hospitalised patients were scanned by ultrasound naive operators after 2 hours of training using the lung ultrasound VSI protocol. Separate blinded readers interpreted both lung ultrasound VSI examinations and standard of care chest radiographs to ascertain the diagnostic value of lung VSI considering chest X-ray as the reference standard. Comparison to clinical diagnosis as documented in the medical record and CT (when available) were also performed. Readers offered a final interpretation of normal, abnormal, or indeterminate/borderline for each VSI examination, chest X-ray, and CT.ResultsOperators scanned 102 subjects (0–89 years old) for analysis. Lung VSI showed a sensitivity of 93% and a specificity of 91% for an abnormal chest X-ray and a sensitivity of 100% and a specificity of 93% for a clinical diagnosis of pneumonia. When any cases with an indeterminate rating on chest X-ray or ultrasound were excluded (n=38), VSI lung ultrasound showed 92% agreement with chest X-ray (Cohen’s κ 0.83 (0.68 to 0.97, p<0.0001)). Among cases with CT (n=21), when any ultrasound with an indeterminate rating was excluded (n=3), there was 100% agreement with VSI.ConclusionLung VSI performed by previously inexperienced ultrasound operators after brief training showed excellent agreement with chest X-ray and high sensitivity and specificity for a clinical diagnosis of pneumonia. Blinded readers were able to identify other respiratory diseases including pulmonary oedema and pleural effusion. Deployment of lung VSI could benefit the health of the global community.

L ung US has dramatically increased in popularity over the last decade and is routinely performed at the patient's bedside, especially in the emergency department and the intensive care unit (ICU) (1-3). Formal training in the performance and interpretation of lung US, however, is not a traditional component of radiology residency education in the United States. As this modality becomes an imaging staple, the diagnostic radiologist should be fluent in lung US performance and interpretation to maintain relevance and assist the ordering clinician. In this imaging essay, the essentials of lung US are described and radiographic correlation for lung US imaging findings on chest radiographs and chest CT images is provided. A discussion of the role of lung US in health care delivery and the future directions of lung US is also included. Utility of Lung USLung US is radiation-free, low-cost, rapid, and portable, allowing real-time examination of pulmonary structures. Meta-analyses suggest that compared with chest radiography, lung US may have higher sensitivity and similar specificity for detection of pleural effusion, pneumonia, pneumothorax, and pulmonary edema (Table ) (4-7). It is increasingly used in the ICU to detect these diseases. Critical care providers have adopted the bedside lung US in emergency (BLUE) protocol as a standardized approach to lung US in the ICU. This protocol can be performed in less than 3 minutes at the bedside and has a diagnostic accuracy greater than 90% for asthma and/ or chronic obstructive pulmonary disease, pneumonia, pneumothorax, pulmonary edema, and pulmonary embolism (1,8). The accuracy for pulmonary embolism derives from the protocol directing the provider to examine the deep venous structures if there is no sign of pulmonary disease. Many practitioners have advocated for the regular use of lung US in the ICU to decrease the use of chest radiography, which is associated with This copy is for personal use only. To order printed copies, contact reprints@rsna.org Although US of the lungs is increasingly used clinically, diagnostic radiologists are not routinely trained in its use and interpretation. Lung US is a highly sensitive and specific modality that aids in the evaluation of the lungs for many different abnormalities, including pneumonia, pleural effusion, pulmonary edema, and pneumothorax. This review provides an overview of lung US to equip the diagnostic radiologist with knowledge needed to interpret this increasingly used modality.