Synthesis of 68Ga-radiopharmaceuticals using both generator-derived and cyclotron-produced 68Ga as exemplified by [68Ga]Ga-PSMA-11 for prostate cancer PET imaging.

[68Ga]Ga-PSMA-11, a urea-based peptidomimetic, is a diagnostic radiopharmaceutical for positron emission tomography (PET) imaging that targets the prostate-specific membrane antigen (PSMA). The recent Food and Drug Administration approval of [68Ga]Ga-PSMA-11 for PET imaging of patients with prostate cancer, expected follow-up approval of companion radiotherapeutics (e.g., [177Lu]Lu-PSMA-617, [225Ac]Ac-PSMA-617) and large prostate cancer patient volumes requiring access are poised to create an unprecedented demand for [68Ga]Ga-PSMA-11 in nuclear medicine clinics around the world. Meeting this global demand is going to require a variety of synthesis methods compatible with 68Ga eluted from a generator or produced on a cyclotron. To address this urgent need in the PET radiochemistry community, herein we report detailed protocols for the synthesis of [68Ga]Ga-PSMA-11, (also known as HBED-CC, Glu-urea-Lys(Ahx)-HBED-CC and PSMA-HBED-CC) using both generator-eluted and cyclotron-produced 68Ga and contrast the pros and cons of each method. The radiosyntheses are automated and have been validated for human use at two sites (University of Michigan (UM), United States; Royal Prince Alfred Hospital (RPA), Australia) and used to produce [68Ga]Ga-PSMA-11 for patient use in good activity yields (single generator, 0.52 GBq (14 mCi); dual generators, 1.04-1.57 GBq (28-42 mCi); cyclotron method (single target), 1.47-1.89 GBq (40-51 mCi); cyclotron method (dual target), 3.63 GBq (98 mCi)) and high radiochemical purity (99%) (UM, n = 645; RPA, n > 600). Both methods are appropriate for clinical production but, in the long term, the method employing cyclotron-produced 68Ga is the most promising for meeting high patient volumes. Quality control testing (visual inspection, pH, radiochemical purity and identity, radionuclidic purity and identity, sterile filter integrity, bacterial endotoxin content, sterility, stability) confirmed doses are suitable for clinical use, and there is no difference in clinical prostate cancer PET imaging using [68Ga]Ga-PSMA-11 prepared using the two production methods.

Cyclotron-based production of 68Ga, [68Ga]GaCl3, and [68Ga]Ga-PSMA-11 from a liquid target.

PURPOSE: To optimize the direct production of 68Ga on a cyclotron, via the 68Zn(p,n)68Ga reaction using a liquid cyclotron target. We Investigated the yield of cyclotron-produced 68Ga, extraction of [68Ga]GaCl3 and subsequent [68Ga]Ga-PSMA-11 labeling using an automated synthesis module. METHODS: Irradiations of a 1.0 M solution of [68Zn]Zn(NO3)2 in dilute (0.2-0.3 M) HNO3 were conducted using GE PETtrace cyclotrons and GE 68Ga liquid targets. The proton beam energy was degraded to a nominal 14.3 MeV to minimize the co-production of 67Ga through the 68Zn(p,2n)67Ga reaction without unduly compromising 68Ga yields. We also evaluated the effects of varying beam times (50-75 min) and beam currents (27-40 µA). Crude 68Ga production was measured. The extraction of [68Ga]GaCl3 was performed using a 2 column solid phase method on the GE FASTlab Developer platform. Extracted [68Ga]GaCl3 was used to label [68Ga]Ga-PSMA-11 that was intended for clinical use. RESULTS: The decay corrected yield of 68Ga at EOB was typically > 3.7 GBq (100 mCi) for a 60 min beam, with irradiations of [68Zn]Zn(NO3)2 at 0.3 M HNO3. Target/chemistry performance was more consistent when compared with 0.2 M HNO3. Radionuclidic purity of 68Ga was typically > 99.8% at EOB and met the requirements specified in the European Pharmacopoeia (< 2% combined 66/67Ga) for a practical clinical product shelf-life. The activity yield of [68Ga]GaCl3 was typically > 50% (~ 1.85 GBq, 50 mCi); yields improved as processes were optimized. Labeling yields for [68Ga]Ga-PSMA-11 were near quantitative (~ 1.67 GBq, 45 mCi) at EOS. Cyclotron produced [68Ga]Ga-PSMA-11 underwent full quality control, stability and sterility testing, and was implemented for human use at the University of Michigan as an Investigational New Drug through the US FDA and also at the Royal Prince Alfred Hospital (RPA). CONCLUSION: Direct cyclotron irradiation of a liquid target provides clinically relevant quantities of [68Ga]Ga-PSMA-11 and is a viable alternative to traditional 68Ge/68Ga generators.

Exploring the role of CT densitometry: a randomised study of augmentation therapy in alpha1-antitrypsin deficiency.

Assessment of emphysema-modifying therapy is difficult, but newer outcome measures offer advantages over traditional methods. The EXAcerbations and Computed Tomography scan as Lung End-points (EXACTLE) trial explored the use of computed tomography (CT) densitometry and exacerbations for the assessment of the therapeutic effect of augmentation therapy in subjects with alpha(1)-antitrypsin (alpha(1)-AT) deficiency. In total, 77 subjects (protease inhibitor type Z) were randomised to weekly infusions of 60 mg x kg(-1) human alpha(1)-AT (Prolastin) or placebo for 2-2.5 yrs. The primary end-point was change in CT lung density, and an exploratory approach was adopted to identify optimal methodology, including two methods of adjustment for lung volume variability and two statistical approaches. Other end-points were exacerbations, health status and physiological indices. CT was more sensitive than other measures of emphysema progression, and the changes in CT and forced expiratory volume in 1 s were correlated. All methods of densitometric analysis concordantly showed a trend suggestive of treatment benefit (p-values for Prolastin versus placebo ranged 0.049-0.084). Exacerbation frequency was unaltered by treatment, but a reduction in exacerbation severity was observed. In patients with alpha(1)-AT deficiency, CT is a more sensitive outcome measure of emphysema-modifying therapy than physiology and health status, and demonstrates a trend of treatment benefit from alpha(1)-AT augmentation.

Deletions in immunoglobulin polypeptide chains as evidence for breakage and repair in DNA.

The partial sequence of the light chain of the myeloma-like immunoglobulin Sac shows a large deletion in its variable region. The sequence provides evidence that the corresponding gene was formed by the repair of DNA broken at nonhomologous positions. Data from other immunoglobulin (heavy) chains containing large deletions are compatible with their genes also being the result of DNA breakage and nonhomologous repair. Single homologous reciprocal exchanges in DNA networks at immunoglobulin loci could be the cause of the nonhomologous breaks. The relevance of these events to the generation of normal antibody variability remains to be determined.

Outcomes for COPD pharmacological trials: from lung function to biomarkers.

The American Thoracic Society/European Respiratory Society jointly created a Task Force on "Outcomes for COPD pharmacological trials: from lung function to biomarkers" to inform the chronic obstructive pulmonary disease research community about the possible use and limitations of current outcomes and markers when evaluating the impact of a pharmacological therapy. Based on their review of the published literature, the following document has been prepared with individual sections that address specific outcomes and markers, and a final section that summarises their recommendations.

Lung density associates with survival in alpha 1 antitrypsin deficient patients.

INTRODUCTION: CT density correlates with quality of life (QOL) scores and impaired upper zone lung density associates with higher mortality in alpha one antitrypsin deficiency (A1ATD). We hypothesised that decline in CT densitometry would relate to survival or deterioration in QOL in A1ATD. METHODS: All augmentation naïve PiZZ patients in the UK A1ATD registry with ≥ two successive quantitative CT scans were selected. Patients were divided into groups based on CT density decline and the relationship to survival and change in QOL compared by univariate analyses and multivariate Cox regression. Analyses were performed for whole lung, upper zone and lower zone density separately. Exploratory analyses of FEV1 subgroups were conducted. RESULTS: 110 patients were identified; 77 had whole lung and lung zone density recorded on two CT scans, 33 patients had upper zone data only on four scans. Decline in lower zone density associated with survival, even after adjustment for baseline lung density (p = 0.048), however upper zone density and whole lung density decline did not. This difference appeared to be driven by those with FEV1 >30% predicted. CONCLUSION: Rate of change in lung densitometry could predict survival in A1ATD.

High-molecular-weight hydroxypropylmethylcellulose. A cholesterol-lowering agent.

BACKGROUND: We assessed the efficacy of a high-molecular-weight hydroxypropylmethylcellulose (K8515) as a cholesterol-lowering agent, the dose-response profile of its action, and the ability of adult subjects to tolerate its ingestion at effective doses. METHODS: These studies were conducted at the Clinical Research Center of The University of Michigan Hospitals, Ann Arbor. Efficacy was assessed in 10 normal and 12 mildly hyperlipidemic subjects in double-blind, randomized crossover trials of 1 and 2 weeks' duration, respectively. The dose-response profile was studied in 12 mildly hypercholesterolemic subjects in a nonrandomized control trial with doses given in escalating order. Tolerance was assessed by a questionnaire of adverse effects and bowel movement habits in all subjects. RESULTS: We found that 10 g of K8515 ingested in a prehydrated form three times a day with meals lowered total cholesterol levels by an average of 1.45 mmol/L (56 mg/dL) (32%) in normal subjects within 1 week. In two studies in subjects with mildly elevated cholesterol levels (with entry levels ranging from 5.35 mmol/L [207 mg/dL] to 6.70 mmol/L [260 mg/dL]), average reductions of 1.00 mmol/L (39 mg/dL) (18%) and 1.15 mmol/L (45 mg/dL) (20%) were observed within the same period. The effect was primarily due to a reduction in low-density lipoprotein cholesterol levels. Low-density lipoprotein levels in normal subjects were an average of 1.10 mmol/L (42 mg/dL) (38%) lower after a week of 10 g of K8515 three times a day with meals, and in the two studies in subjects with mild hyperlipidemia, the reductions in low-density lipoprotein levels after 1 week were 0.95 mmol/L (37 mg/dL) (23%) and 1.05 mmol/L (40 mg/dL) (25%). Although there was a tendency for high-density lipoprotein cholesterol levels to decrease, this was significant only in normal subjects. Decreases in cholesterol levels were not accompanied by any rise in triglyceride levels. Dose-response studies in those with mildly elevated cholesterol levels indicated that it is possible to achieve a 15% decrease in low-density lipoprotein cholesterol levels within 1 week at a dose of 6.7 g three times a day, with minimal adverse effects. CONCLUSION: These results suggest a role for high-molecular-weight hydroxypropylmethylcellulose in the clinical treatment of mild hypercholesterolemia.

Calcium-induced damage of rat heart mitochondria.

The damage which may be caused to heart mitochondria by the rapid uptake of calcium when oxygen is restored after a period of anoxia is monitored by the deterioration in phosphorylation performance. Methods of protecting mitochondria from this damage by preventing calcium uptake and by chelating cytoplasmic calcium are considered.

Multiple myeloma (light chain disease) with rheumatoid-like amyloid arthropathy and mu-heavy chain fragment in the serum.

A 52 year old man presented with multiple myeloma and widespread amyloidosis involving joints, bursae- carpal tunnels, lymph nodes and subcutaneous tissue. Osteolytic bone lesions and pathologic fracture of the neck of the left femur were found. Bone marrow was infiltrated with both plasmacytes and lymphocytes. The majority of plasma cells contained large cytoplasmic vacuoles. Free kappa II type light chains and mu-heavy chain fragment were detected in the serum, and kappa II type Bence Jones protein was found in the urine. The molecular weight of the mu-heavy chain fragment was found to be approximately 50,000 daltons. An immunofluorescence study, using the double labelling technic, showed that the majority of plasmacytes in bone marrow contained both mu and kappa antigenic determinants in the cytoplasm. A review of the 12 previously described patients with mu-heavy chain fragment in the serum showed a variable clinical picture, thus their natural history and therapeutic response are difficult to evaluate at the present time. It seems that mu-heavy chain fragment can be found in a variety of clinical conditions and that mu-heavy chain disease cannot yet be accepted as a separate clinical entity.

The morphological identification of pathogenic yeasts using carbohydrate media.

Eight isolates of C. albicans were used to determine the frequency with which germ tube formation occurred: on rice extract -Tween 80 agar, on its components, and on 1% bactopeptone agar after three hr at 37 degrees C; in 0.5% aqueous solution of various carbohydrates; in various concentrations of glucose; on 0.5 and 0.1% glucose agar and on various types of agar alone. Subsequently 250 isolates of yeast of the genera Candida, Torulopsis, Trichosporon, Cryptococcus, and Saccharomyces, which were obtained from a clinical laboratory, were spread on rice extract -Tween 80 agar and on 0.1% glucose agar and covered with coverslips. Direct microscopic examination after incubation for three hours at 37 degrees C demonstrated germ tube formation by all 140 isolates of C. albicans, but by none of the other yeasts. The characteristic features of the pseudomycelia of isolates of Candida and Trichosporon were evident on reexamination after a further 45 to 69 hours at room temperature (22 degrees C). These morphological observations suggested the identity of the isolates of Torulopsis, Cryptococcus, and Saccharomyces but identified virtually all (98.2%) of those of the genera which formed pseudomycelia. Of the latter group only four isolates required fermentation and assimilation tests to determine whether they were C. parapsilosis (1) or C. guilliermondii (3).

Growth and Sucrose Metabolism of Carrot Callus Strains with Normal and Low Acid Invertase Activity.

The properties of two strains of carrot (Daucus carota) callus are presented. One has a very low acid invertase activity which is accompanied by differences in morphology and metabolic rate, but not in growth rate. We conclude that one of the main functions of plant acid invertases is in controlling the levels of sugars which, by interaction with hormones, affect differentiation, both morphological and biochemical. The effect of tris on sucrose metabolizing enzymes, and the cause of the "sucrose effect" are considered.

Recurrent skin infection with Rhodococcus in an immunosuppressed patient.

A renal transplant patient taking prednisone and azathioprine has had repeated episodes of skin infection with the soil saphrophyte Rhodococcus. Human disease with this organism has not been proved before. Although the lesions have always responded to antibiotics, frequent recurrence makes the long-term outlook uncertain.

Psychophysiological stress responses, muscle tension, and neck and shoulder pain among supermarket cashiers.

This study examined psychological and physiological stress, as well as muscle tension and musculoskeletal symptoms, among 72 female supermarket cashiers. Stress levels were found to be significantly elevated at work, as reflected in the catecholamines, blood pressure, heart rate, electromyographic (EMG) activity, and self-reports. Fifty cashiers (70%) suffering from neck-shoulder pain (trapezius myalgia) were found to have higher EMG activity at work and reported more tension after work. Women who kept a diary for 1 week and reported more musculoskeletal pain (above the median) were older, had higher blood pressure, and reported more work stress and psychosomatic symptoms. The elevated stress levels at work are consistent with data from workers involved in other types of repetitive tasks and can be important for the high prevalence of neck and shoulder symptoms among the cashiers.

Ocular cryptococcosis in New Zealand.

A patient with unexplained lung abscess six years previously, developed chronic meningitis, and later, bilateral chorioretinitis. The organism found was Cryptococcus neoformans. The patient was successfully treated with amphotericin B and 5-fluorocytosine.

The spectrum of systemic candidiasis at Auckland Hospital.

Systemic candidiasis is uncommon. We reviewed our experience with this disease from the infectious disease unit, Auckland Hospital, between 1982 and 1988, because many of these patients are referred to us. We then selected 11 of them to highlight particular presentations, diagnostic or management issues. We included both compromised and noncompromised patients from medical and surgical services. Candida albicans was the most common cause, but we also saw patients infected with C glabrata, C parapsilosis, and C tropicalis and present them to exemplify their different clinical presentations. Demonstrable fungaemia is uncommon in patients with systemic candidiasis, serological techniques are both insensitive and nonspecific and patients are often too ill from underlying disease to allow for invasive diagnostic procedures. Thus diagnosis is often difficult. Parenteral amphotericin B with or without 5-fluorocytosine is still the main antifungal treatment. Triazole antifungals may change that in the future. Systemic candidiasis retains a high mortality: careful individualised management of patients may improve mortality and morbidity.

The Auckland skin clinic tinea pedis and erythrasma study.

Three hundred consecutive patients attending the Auckland Hospital dermatology clinic were examined clinically and microbiologically for evidence of interdigital or plantar mycological or bacterial infection. One hundred and nine patients were shown by laboratory investigation to have an infection. Of these, only 89 displayed clinical signs of infection. Erythrasma, a desquamative condition caused by Corynebacterium minutissimum, was the commonest infection in this study. The commonest dermatophyte isolated was Trichophyton mentagrophytes var interdigitale. There was a significant rise in the incidence of both types of infection with age.

Cryptococcal meningitis in Auckland 1969-89.

Twenty-six patients with cryptococcal meningitis were seen in Auckland between 1969 and 1989. The incidence of cryptococcal meningitis in Auckland residents was 0.12 cases/100,000/year. Ten (38%) of the patients were Maori or Pacific Island Polynesians. Nineteen (73%) had a predisposing cause, including immunosuppressive therapy in nine and the acquired immunodeficiency syndrome (AIDS) in seven. The most common presenting syndrome was a subacute or chronic meningitis. Other clinical syndromes included a slowly progressive ataxia, polyradiculopathy, and headache with vomiting. In two patients, the symptoms of meningitis were overshadowed by those of systemic cryptococcal infection. Delay in making the diagnosis was common. The most sensitive method for diagnosing cryptococcal meningitis was the cerebrospinal fluid cryptococcal antigen test. Antifungal therapy cured 17 of the 25 (68%) treated patients overall, 15 of the 19 (79%) without AIDS and six of the seven with no underlying disease.